struvite and Urinary-Tract-Infections

Struvite is one of the most common urinary/kidney stones, composed of magnesium ammonium phosphate (MgNHPO. This review summarizes various reports on the factors responsible for inducing struvite stones in the kidney and gives a detailed account of studies on inhibition of growth of struvite crystals.. The presence of urea-splitting bacteria such as Proteus mirabilis and alkaline pH plays a crucial role in struvite formation. In vitro inhibition of struvite stones by various chemical agents were examined mainly in artificial urine whereas inhibition by herbal extracts was studied in vitro by gel diffusion technique. Herbal extracts of curcumin, Boerhaavia diffusa Linn, Rotula aquatica and many other plants, as well as some chemicals like pyrophosphate, acetohydroxamic acid, disodium EDTA and trisodium citrate, were reported to successfully inhibit struvite formation.. The present review recapitulates various factors affecting the growth of struvite urinary stones and the inhibitory role of certain chemicals and herbal extracts. Most of the tested plants are edible hence can be easily consumed without any adverse effects whereas the side effects of chemicals are unknown due to lack of toxicity studies. Thus, the use of herbal extracts might serve as an alternate and safe therapy for prevention of struvite stones.

Topics: Animals; Crystallization; Humans; Kidney; Plant Preparations; Struvite; Urinary Calculi; Urinary Tract Infections; Urolithiasis

Infection stones-which account for 10-15% of all urinary calculi-are thought to form in the presence of urease-producing bacteria. These calculi can cause significant morbidity and mortality if left untreated or treated inadequately; optimal treatment involves complete stone eradication in conjunction with antibiotic therapy. The three key principles of treating struvite stones are: removal of all stone fragments, the use of antibiotics to treat the infection, and prevention of recurrence. Several methods to remove stone fragments have been described in the literature, including the use of urease inhibitors, acidification therapy, dissolution therapy, extracorporeal shockwave lithotripsy, ureteroscopy, percutaneous nephrolithotomy (PCNL), and anatrophic nephrolithotomy. PCNL is considered to be the gold-standard approach to treating struvite calculi, but adjuncts might be used when deemed necessary. When selecting antibiotics to treat infection, it is necessary to acquire a stone culture or, at the very least, urine culture from the renal pelvis at time of surgery, as midstream urine cultures do not always reflect the causative organism.

Topics: Algorithms; Anti-Bacterial Agents; Crystallization; Drug Therapy, Combination; Hemostatics; Humans; Kidney Calculi; Lithotripsy; Magnesium Compounds; Nephrostomy, Percutaneous; Phosphates; Struvite; Treatment Outcome; Urease; Ureteroscopy; Urinary Tract Infections

The classic "infection stone" struvite is formed as a result of metabolic activity of urease-positive bacteria from alkaline urine with pH-values above 7.5. Due to improved infection diagnostics and antibiotic therapy, the occurrence of infection-related urinary stones in the western industrialized world decreases, despite the generally increasing prevalence rates of urolithiasis in these societies. Struvite is often associated with other mineral phases. These accessory mineral phases could indicate other, non-infection-related causes of urinary stone formation. Thus, mineral analysis is always recommended. Struvite stones as well as struvite encrustations on urinary tract implants are characterized by rapid growth. The rapid growth-related embedding of urease-positive bacteria in the crystalline material makes the urinary stone a persistent source of recurrent urinary tract infections. According to the German Society of Urology guidelines on urolithiasis, a patient with the diagnosis "infection stone" should be assigned to the "high-risk" patient group. Complete stone and debris removal, as well as a special metaphylaxis strategy are required to initiate successful stone therapy.

Topics: Acid-Base Equilibrium; Bacterial Infections; Drug Resistance, Microbial; Humans; Magnesium Compounds; Phosphates; Recurrence; Risk Factors; Struvite; Urease; Urinary Calculi; Urinary Tract Infections

Topics: Calcium; Child; Child, Preschool; Cystine; Female; Hematuria; Humans; Kidney Calculi; Magnesium Compounds; Male; Metabolic Diseases; Oxalates; Phosphates; Struvite; Uric Acid; Urinalysis; Urinary Calculi; Urinary Tract Infections

Glycosaminoglycans (GAGs) are suspended in urine and are present on tissue surfaces in the urinary tract. Consequently, they have the potential to influence any pathological disorder in this environment, including urinary tract infections by Proteus mirabilis and struvite (NH4MgPO4.6H2(0)) urolithiasis. Although GAGs, suspended in urine, may inhibit the formation of other types of calculus minerals, no such effect has been reported in struvite calculi. Nevertheless, GAGs are a major component of the organic matrix of all types of urinary calculi. In contrast, there is evidence that the GAG layer on the bladder surface may act as a defence mechanism against infection by inhibiting bacterial adhesion. More studies are needed to elucidate fully the role of GAGs in urinary infections and struvite urolithiasis.

Topics: Glycosaminoglycans; Humans; Magnesium Compounds; Phosphates; Proteus Infections; Proteus mirabilis; Struvite; Urinary Calculi; Urinary Tract Infections

Topics: Enterobacteriaceae; Enterobacteriaceae Infections; Humans; Magnesium; Magnesium Compounds; Phosphates; Struvite; Urease; Urinary Calculi; Urinary Tract Infections

Urinary stone disease is a common affliction in our society and may affect 1 to 5 per cent of the population. The physician involved in caring for the stone-forming patient must have a thorough understanding of the metabolic as well as anatomic abnormalities that may lead to repeat stone formation. The authors review the common metabolic abnormalities frequently seen in the stone-forming patient and present the current medical management of these problems. Ongoing changes in the surgical approach to urinary stones are also discussed.

Topics: Calcium; Crystallization; Cystine; Cystinuria; Humans; Kidney Calculi; Magnesium; Magnesium Compounds; Phosphates; Physical Examination; Struvite; Tomography, X-Ray Computed; Ultrasonography; Uric Acid; Urinary Calculi; Urinary Tract Infections; Urine; Urography

Topics: Animals; Cat Diseases; Cats; Dog Diseases; Dogs; Humans; Magnesium; Magnesium Compounds; Phosphates; Radiography; Struvite; Ureaplasma; Urinary Calculi; Urinary Tract Infections

This case is typical of recurrent urolithiasis managed by repeated surgery. Retrospective assessment of the disorder indicates the need for quantitative analyses of uroliths removed by cystotomy. Compliance of the owners with recommendations to minimize recurrent urolithiasis might have been beneficial. Results of medical therapy designed to induce dissolution of uroliths in this case are representative of preliminary findings of medical dissolution of naturally occurring struvite uroliths in ten other cats. It is of interest that the uroliths dissolved even though no effort was made to induce diuresis. The underlying cause of UTI in this patient may have been damage to the lower urinary tract induced by previous diagnostic and therapeutic procedures and/or sterile struvite uroliths that compromised local host defense mechanisms. Lack of urease production by the uropathogens suggests that they did not play a causative role in formation of uroliths. The need for preventative therapy of recurrent formation of uroliths after their medical dissolution is worthy of further comment. In this patient, specific measures to prevent urolith recurrence were not initiated because it is a part of a prospective clinical study. In the event uroliths recur, medical therapy designed to induce dissolution of uroliths would be repeated. Need for long-term preventative therapy would be dependent on the time interval between recurrent episodes (weeks, months, or years), and the effectiveness of medical therapy for urolith dissolution. Long-term prophylactic therapy would include urine acidifiers and diets low in magnesium.

Topics: Ammonium Chloride; Animals; Anti-Infective Agents; Anti-Inflammatory Agents; Cat Diseases; Cats; Diverticulum; Female; Magnesium; Magnesium Compounds; Male; Methionine; Parasympatholytics; Phosphates; Struvite; Urachus; Urinary Calculi; Urinary Tract Infections

Urolithiasis is a common clinical problem in dogs. Struvite and calcium oxalate are the predominant mineral types in dog urolithiasis. The aim of the present study was to compare the effect of two commercial dry foods formulated for the management of struvite urolithiasis with different anion-cation balance on urinary pH. For the trial, twelve privately owned adult dogs showing struvite urolithiasis were studied. The dogs were randomly divided into two groups (A and B) and fed two dissolving diets for 3 months. The analyses of urine were repeated six times. In both diets, the anion-cation balance was negative ( - 203 and - 192 for diets A and B, respectively). At the first urine analysis, pH values of all the dogs were close to 8.0, and bacteria were present in about 70 % of the samples and thus an antimicrobial was administered for 1 week. Both groups showed a progressive decrease in pH values, and after 2 months, in both cases, the recommended pH values for stone dissolution were achieved. From the sampling at 30 d, group A showed pH values significantly (P < 0.05) lower than group B, probably due to the lower anion-cation balance of diet A. The combination of antimicrobial and dietary therapy allowed the dissolution of struvite uroliths in both groups, even if the utilisation of the diet characterised by the lower anion-cation balance seems to decrease the urinary pH more rapidly. In this case, it seems necessary to interrupt the dietary treatment in order to avoid the risk of other diseases.

Topics: Animal Feed; Animal Nutritional Physiological Phenomena; Animals; Anti-Bacterial Agents; Diet; Dog Diseases; Dogs; Fluoroquinolones; Hydrogen-Ion Concentration; Magnesium Compounds; Phosphates; Struvite; Urinary Tract Infections; Urolithiasis

Long-term administration of acetohydroxamic acid to dogs with experimentally induced urease-positive staphylococcal urinary tract infections and struvite urolithiasis resulted in dose-dependent inhibition of urolith growth or urolith dissolution. Inhibition of urolith growth was associated with drug dose-dependent reduction of urine urease activity, urine pH, crystalluria, pyuria, hematuria, and proteinuria. Lesions of the urinary tract of dogs treated with acetohydroxamic acid were less severe than those of control dogs. Dose-dependent adverse drug reactions included reversible hemolytic anemia, abnormal red cell morphology, and abnormalities of bilirubin metabolism.

Topics: Animals; Dog Diseases; Dogs; Dose-Response Relationship, Drug; Drug Administration Schedule; Enzyme Inhibitors; Female; Hydroxamic Acids; Magnesium Compounds; Phosphates; Struvite; Urinary Bladder Calculi; Urinary Tract Infections

A 4-month-old, 7 kg, intact male, Bernese mountain dog was presented for obstructive struvite ureterolithiasis. Multiple urethroliths, ureteroliths, and urocystoliths were present. Based on an abdominal ultrasound, there was severe left hydronephrosis and hydroureter from distal ureterolith obstruction, just proximal to the vesicoureteral junction. The dog was not azotemic. Successful treatment was accomplished

Topics: Animals; Dog Diseases; Dogs; Female; Humans; Male; Methicillin-Resistant Staphylococcus aureus; Struvite; Ureterolithiasis; Urinary Tract Infections; Urolithiasis

This study aims to identify clinical factors that may predispose struvite stone patients to urosepsis following percutaneous nephrolithotomy (PCNL).. A retrospective review was conducted on patients who received PCNL for struvite stones. The Systemic Inflammatory Response Syndrome (SIRS) criteria and quick-Sepsis Related Organ Failure Assessment (q-SOFA) criteria were used to identify patients who were at an increased risk for urosepsis. Statistical analysis was performed using Fisher's exactness test, Wilcoxon rank test, and logistic regression.. Chart review identified 99 struvite stone patients treated with PCNL. Post-operatively, 40 patients were SIRS positive (≥2 criteria) and/or q-SOFA positive (score ≥2). Using SIRS as an approximation for urosepsis, longer operative times (p<0.001), higher pre-operative white blood cell counts (p=0.01), greater total stone surface area (p<0.0001), and pre-operative stenting (OR, 5.75; p=0.01) were identified as independent risk factors for urosepsis. Multivariate analysis demonstrated pre-operative stenting (OR, 1.46; p=0.01) to be a risk factor. With q-SOFA, univariable analysis found that antibiotic use within 3 months prior to a PCNL (OR, 4.44; p=0.04), medical comorbidities (OR, 4.80; p=0.02), longer operative times (p<0.001), lengthier post-operative hospitalization (p<0.01), and greater total stone surface area (p<0.0001) were risk factors for urosepsis. Multivariate analysis revealed that bladder outlet obstruction (OR, 2.74; p<0.003) and pre-operative stenting (OR, 1.27; p=0.01) significantly increased odds of being q-SOFA positive.. Several risk factors for urosepsis following PCNL for struvite stones have been identified. These risk factors should be taken into consideration in peri-operative care to mitigate the risks of urosepsis.

Topics: Adult; Aged; Female; Humans; Kidney Calculi; Male; Middle Aged; Nephrolithotomy, Percutaneous; Postoperative Complications; Retrospective Studies; Risk Factors; Sepsis; Struvite; Urinary Tract Infections

To determine if treatment of non-obstructing urolithiasis is effective in management of recurrent UTI.. A retrospective review was performed of patients undergoing elective management of non-struvite upper tract urinary calculi with recurrent UTI from 2009 to 2016. Recurrent UTI was defined at ≥ 3 UTI in 12 months, with symptoms and documented urine culture. Preoperative CT was performed in all patients to determine stone burden. All patients had postoperative imaging and ≥ 12 months of follow-up. Pre- and postoperative variables were between patients who had recurrent UTI after treatment versus those who did not.. 46 patients met inclusion criteria. 42 (91.3%) were female. Median age was 63.7 years (IQR 49.1, 73.4) and median total stone burden was 20 mm (IQR 14-35). Within the cohort, 20 (43.5%) underwent ureteroscopy only, 26 (56.5%) underwent PCNL ± URS, and none underwent ESWL. Median postoperative follow-up was 2.9 years (IQR 2.0, 4.3). Only five patients (10.9%) had recurrent UTI after treatment. 80% were with the preoperative pathogen. The presence of residual stone was an independent risk factor for recurrent UTI after treatment (p < 0.046). Diabetes, hypertension, immunosuppression and chronic kidney disease were not.. Stone removal for patients with recurrent UTIs was associated with a high rate of success (89.1%) in elimination of further recurrent UTIs. Residual fragments are independently associated with persistent recurrent UTIs and thus, complete stone removal is of paramount importance in treatment of this patient population.

Topics: Aged; Female; Humans; Incidence; Kidney Calculi; Male; Middle Aged; Nephrolithotomy, Percutaneous; Recurrence; Retrospective Studies; Struvite; Treatment Outcome; Ureteral Calculi; Ureteroscopy; Urinary Tract Infections

A 52-year-old man with flank pain on the right side presented to the emergency room. A computer tomography of the abdomen showed a right ureterolithiasis with 3.5 mm stone in the proximal ureter with consecutive grade 2 hydronephrosis. After standard treatment of the right ureterolithiasis, there was a relapse on the left side and throughout the entire upper and lower urinary tract with struvite stones due to a persistent infection with Proteus mirabilis.. Auf der Notfallstation präsentiert sich ein 52-jähriger Patient mit Flankenschmerzen rechtsseitig. Eine Computertomographie des Abdomens zeigte eine Ureterolithiasis rechts bei 3,5-mm-Konkrement im proximalen Ureter mit konsekutiver Hydronephrose Grad II. Nach standardmäßiger Behandlung der Ureterolithiasis rechts kam es zu einem Rezidiv auf der linken Seite und im Verlauf des ganzen oberen und unteren Harntrakts mit Struvitsteinen bei einem persistierenden Infekt mit Proteus mirabilis.

Topics: Humans; Male; Middle Aged; Proteus mirabilis; Struvite; Urinary Calculi; Urinary Tract Infections

Poorly crystalline and amorphous precipitate (PCaAP) is one of the components of the so-called infectious urinary stones, which are the result of the activity of urease-producing microorganisms, mainly from the Proteus species, in particular Proteus mirabilis. The main component of this kind of stones is crystalline struvite (MgNH

Topics: Apatites; Durapatite; Humans; Lipopolysaccharides; Proteus mirabilis; Struvite; Urinary Calculi; Urinary Tract Infections; Urine; Urolithiasis

Struvite urolithiasis with bacterial urinary tract infection (UTI) is commonly reported in dogs; few data exist to describe successful dissolution protocols in dogs with naturally occurring disease. We hypothesized that a dry therapeutic urinary diet combined with targeted antimicrobial therapy can effectively dissolve presumptive struvite cystolithiasis in dogs with naturally occurring urease-producing bacterial UTI.. Ten dogs with presumed infection-induced struvite cystolithiasis based on lower urinary tract signs (LUTS), radiodense cystoliths, and urease-producing bacterial UTI were enrolled. At enrollment, antimicrobials and dry therapeutic urinary diet were dispensed. In addition to lack of radiographic resolution of urolithiasis, dogs with persistent clinical signs were considered non-responders. There was no significant difference in pH between responders and non-responders; USG was significantly higher in the responder group. Recheck visits continued until radiographic dissolution or failure was documented. Five of the 10 dogs achieved radiographic dissolution of cystolithiasis within a median of 31 days (range 19-103). In the other 5 dogs, surgical urolith removal was necessary due to persistent LUTS (3 dogs within 2 weeks) or lack of continued dissolution noted radiographically (1 dog with numerous cystoliths failed at day 91; 1 dog failed by day 57 with questionable owner compliance).. Dissolution of urinary tract infection induced struvite cystoliths can be accomplished in some dogs fed this dry therapeutic urinary diet in conjunction with antimicrobial therapy. Case selection could increase the likelihood of successful dissolution; however, if calcium phosphate is present, this could also prevent stone dissolution. If clinical signs persist despite diet and antimicrobials, stone removal is advised.

Topics: Animals; Anti-Infective Agents; Dog Diseases; Dogs; Struvite; Treatment Outcome; Urinary Bladder Calculi; Urinary Tract Infections; Urolithiasis

To evaluate the association of clinical factors on outcomes in patients with spinal cord injury (SCI) undergoing ureteroscopy. Immobility, recurrent urinary tract infection, and lower urinary tract dysfunction contribute to renal stone formation in patients with SCI. Ureteroscopy is a commonly utilized treatment modality; however, surgical complication rates and outcomes have been poorly defined. Evidence guiding safe and effective treatment of stones in this cohort remains scarce.. Records were retrospectively reviewed for patients with SCI who underwent ureteroscopy for kidney stones from 1996 to 2014 at a single institution. Multivariate relationships were evaluated using a general estimating equation model.. Forty-six patients with SCI underwent a total of 95 ureteroscopic procedures. After treatment, stone-free rate was 17% and 20% with <2-mm fragments. The complication rate was 21%. On multivariate analysis, SCI in cervical (C) levels was associated with higher risk of complications (C3: odds ratio [OR] 3.83, 95% confidence interval [CI] 2.17-6.98; C6: OR 3.83, 95% CI 1.08-13.53). American Spinal Injury Association Scale A classification was associated with a lower probability of stone-free status (OR 0.16, 95% CI 0.03-0.82). Patients averaged 2.2 procedures yet more procedures were associated with lower stone-free status (OR 0.83, 95% CI 0.03-0.32). Chronic obstructive pulmonary disease and bladder management modality were not associated with stone-free status or complications.. In patients with SCI, higher injury level and complete SCI were associated with worse stone clearance and more complications. Stone-free rate was 17%. Overall, flexible ureteroscopy is a relatively safe procedure in this population. Alternative strategies should be considered after failed ureteroscopy.

Topics: Adult; Aged; Apatites; Cardiovascular Diseases; Comorbidity; Diabetes Mellitus; Female; Humans; Kidney Calculi; Lithotripsy, Laser; Male; Middle Aged; Multivariate Analysis; Operative Time; Postoperative Complications; Renal Insufficiency, Chronic; Respiratory Tract Diseases; Spinal Cord Injuries; Struvite; Treatment Outcome; Ureteroscopy; Urinary Bladder, Neurogenic; Urinary Tract Infections

Urolithiasis affects primarily the urinary tract and complications as debilitating as renal failure may develop. Determining the chemical composition of uroliths can aid management and prevention of recurrence in patients.. To determine the chemical composition and anatomical distribution of uroliths in Nigeria.. This descriptive cross-sectional study was conducted between March 2014 and February 2016, in a tertiary hospital in Nigeria. We reviewed the outcomes of uroliths of adult patients sent to our laboratory for chemical analyses. Samples were analyzed using simple qualitative tests.. 52 adult patients were included with a mean age (SD) of 46.6 (12.6) years. Males (76.9%) were more affected than females (23.1%). For both sexes, highest occurrence of stones was in bladder (85.7%). Calcium-containing stones had the highest occurrence (85.2%) and predominated in the renal, ureter and urethra, followed by struvite stones (59.5%). In the bladder, struvite stones were predominant (85.8%), with calcium-containing stones accounting for 71.4%.. This study showed that struvite and calcium phosphate-containing stones constitute majority of uroliths in our setting with low occurrence of calcium oxalate stones. This indicates that urinary tract infection most likely plays a substantial role in the formation of uroliths in Nigerians. Modern methods of stone analysis is advocated to further define management options.

Topics: Adult; Aged; Calcium Phosphates; Cross-Sectional Studies; Female; Humans; Magnesium Compounds; Male; Middle Aged; Nigeria; Struvite; Tertiary Care Centers; Urinary Calculi; Urinary Tract Infections; Urolithiasis

Topics: Aged; Anti-Bacterial Agents; Biofilms; Catheter-Related Infections; Corynebacterium; Corynebacterium Infections; Humans; Male; Opportunistic Infections; Recurrence; Struvite; Urinary Catheterization; Urinary Tract Infections; Urolithiasis

Urinary stasis is a risk factor for recurrent urinary tract infection (UTI). Homozygous mutant Megabladder (Mgb-/-) mice exhibit incomplete bladder emptying as a consequence of congenital detrusor aplasia. We hypothesize that this predisposes Mgb-/- mice to spontaneous and experimental UTI.. Mgb-/-, Mgb+/-, and wild-type female mice underwent serial ultrasound and urine cultures at 4, 6, and 8 weeks to detect spontaneous UTI. Urine bacterial isolates were analyzed by Gram stain and speciated. Bladder stones were analyzed by x-ray diffractometry. Bladders and kidneys were subject to histologic analysis. The pathogenicity of coagulase-negative Staphylococcus (CONS) isolated from Mgb-/- urine was tested by transurethral administration to culture-negative Mgb-/- or wild-type animals. The contribution of urinary stasis to CONS susceptibility was evaluated by cutaneous vesicostomy in Mgb-/- mice.. Mgb-/- mice develop spontaneous bacteriuria (42%) and struvite bladder stones (31%) by 8 weeks, findings absent in Mgb+/- and wild-type controls. CONS was cultured as a solitary isolate from Mgb-/- bladder stones. Bladders and kidneys from mice with struvite stones exhibit mucosal injury, inflammation, and fibrosis. These pathologic features of cystitis and pyelonephritis are replicated by transurethral inoculation of CONS in culture-negative Mgb-/- females, whereas wild-type animals are less susceptible to CONS colonization and organ injury. Cutaneous vesicostomy prior to CONS inoculation significantly reduces the quantity of CONS recovered from Mgb-/- urine, bladders, and kidneys.. CONS is an opportunistic uropathogen in the setting of urinary stasis, leading to enhanced UTI incidence and severity in Mgb-/- mice.

Topics: Animals; Bacteriuria; Cystitis; Disease Susceptibility; Female; Hydrogen-Ion Concentration; Magnesium Compounds; Mice; Mice, Mutant Strains; Phosphates; Pyelonephritis; Staphylococcus; Struvite; Urinary Bladder; Urinary Diversion; Urinary Tract; Urinary Tract Infections; Urolithiasis

Proteus mirabilis cause urinary tract infections which are recurrent and can lead to formation of urinary calculi. Both bacterial and the host factors are involved in the development of urolithiasis. To determine the impact of glycosaminoglycans (GAGs) in the formation of P. mirabilis-induced urinary stones, we investigated the in vitro crystallization, aggregation and adhesion of crystals in the presence of GAGs naturally appearing in urine. Crystallization experiments were performed in synthetic urine infected with P. mirabilis in the presence of: hyaluronic acid (HA), heparan sulfate (HS), chondroitin sulfate A, B and C (ChSA, ChSB, ChSC). The intensity of crystallization and aggregation were established by counting particles and phase-contrast microscopy. To analyze the adhesion of crystals, we used normal urothelium and (45)Ca isotope-labeled crystals. In the presence of ChSC, both the size of the crystals formed and their number were higher compared with the control. GAGs increased crystals adhesion to the cells, but only for ChSA this effect was significant. Chondroitin sulfates, which accelerate the first stages of infection-induced stones formation, may play an important role in the pathogenesis of infectious urolithiasis.

Topics: Adhesiveness; Apatites; Cell Line; Chondroitin Sulfates; Crystallization; Dermatan Sulfate; Glycosaminoglycans; Heparitin Sulfate; Host-Pathogen Interactions; Humans; Hyaluronic Acid; Magnesium Compounds; Microscopy, Phase-Contrast; Models, Biological; Phosphates; Proteus Infections; Proteus mirabilis; Struvite; Urinary Calculi; Urinary Tract Infections; Urothelium; Virulence

Topics: Crystallization; Diagnosis, Differential; Humans; Kidney Calculi; Magnesium Compounds; Male; Middle Aged; Phosphates; Struvite; Tomography, X-Ray Computed; Ureteroscopy; Urinary Tract Infections

To characterize patients who form nonstruvite stones associated with infection (secondarily infected calculi), and to define the bacteria associated with these.. Patients undergoing percutaneous nephrolithotomy were prospectively recruited. Medical records were reviewed, and stones were analyzed using micro computed tomography and infrared spectroscopy. A fragment of each stone was sent for bacterial culture. Patients were categorized by stone culture results (SC ±) and the presence of struvite (ST ±). The Fisher exact test was used for comparison of proportion. Sterility of intraoperative SC was established with independently collected controls.. In total, 125 patients were enrolled: 24 SC+/ST-, 19 SC+/ST+, and 82 SC-/ST-. Proportions of patients with prior urologic surgery, diabetes, and immunodeficiency were similar between groups. Patients with neurogenic bladder were more likely to have SC+/ST+ stones or SC+/ST- stones than SC-/ST- stones (26% vs 8% vs 0%, respectively; P <.01). Among patients with metabolic evaluations, hypocitraturia was found in 31.6% (6 of 19) SC+/ST- patients, 46.7% (7 of 15) SC+/ST+ patients, and 26.0% (19 of 73) of SC-/ST- patients (P = .28). Approximately 40% of cultured organisms in the secondarily infected calculi possessed urease and another 40% citrate lyase activities.. Secondarily infected stones were detected in approximately 20% of this surgical cohort and may be more common than previously appreciated. Neurogenic bladder appeared to predispose patients to either struvite or secondarily infected stones. The role of bacterial infection in stone formation is unclear but may include alteration of urinary components, acting as a nidus for crystallization, or inducing inflammation.

Topics: Adult; Aged; Calcium Oxalate; Calcium Phosphates; Cohort Studies; Female; Humans; Incidence; Magnesium Compounds; Male; Middle Aged; Nephrostomy, Percutaneous; Phosphates; Postoperative Care; Preoperative Care; Prognosis; Prospective Studies; Risk Assessment; Struvite; Uric Acid; Urinalysis; Urinary Tract Infections; Urolithiasis

This study was conducted to determine the composition of staghorn stones and to assess the proportion of infected stones as well as the correlation between infection in the stones and bacteria grown in urine. Samples of 45 consecutive stones removed through anatrophic nephrolithotomic procedures were taken from the operation site and samples of urine were obtained by simultaneous bladder catheterization. The frequency of infection in the stones and correlation between infection of stone and urine samples were determined with respect to the composition of the stones. Twenty-two males and 23 females, with respective mean ages of 48.3 ± 15.6 years and 51 ± 7.4 years, were studied. The stone and urine cultures yielded positive results in ten and 16 patients, respectively, of a total of 45 patients (22.2% and 35.5%, respectively). Calcium oxalate was the main constituent of staghorn stones, seen in 31 patients (68.8%), uric acid in 12 patients (26.6%) and struvite and/or calcium phosphate in 11 patients (24.4%). In seven of ten stones with bacterial growth, bacteria were isolated from urine cultures as well, which accounted for a concordance rate of 70%. The bacteria grown in the stone were the cause of urinary tract infection (UTI) in 43.5% of the cases. Stone infection was significantly associated with UTI (OR = 6.47; 95% CI 1.43-31.7, P = 0.021) and presence of phosphate in the stones (OR = 18, 95% CI 3.28-99.6, P = 0.0006). E. coli was the most common bacteria grown from the stones, and was isolated in 50% of the cases; Ureaplasma urealyticum was the most common organism causing UTI, grown in 62.5% of the urine samples. There was a high concordance rate between bacteria in the stones and urine. These findings indicate that the urine culture can provide information for selection of an appropriate anti-microbial agent for stone sterilization. In addition, preventing re-growth or recurrence of stones and treatment of post-surgical infections would be facilitated based on the results of the urine culture.

Topics: Adult; Aged; Anti-Bacterial Agents; Calcium Oxalate; Calcium Phosphates; Female; Humans; Iran; Kidney Calculi; Magnesium Compounds; Male; Middle Aged; Nephrostomy, Percutaneous; Odds Ratio; Phosphates; Prevalence; Risk Factors; Struvite; Treatment Outcome; Uric Acid; Urinary Catheterization; Urinary Tract Infections; Urine

The presence of infectious microorganisms in urinary stones is commonly inferred from stone composition, especially by the presence of struvite in a stone. The presence of highly carbonated apatite has also been proposed as a marker of the presence of bacteria within a stone. We retrospectively studied 368 patients who had undergone percutaneous nephrolithotomy (PCNL), and who also had culture results for both stone and urine. Urine culture showed no association with stone mineral content, but stone culture was more often positive in struvite-containing stones (73 % positive) and majority apatite stones (65 %) than in other stone types (54 %, lower than the others, P < 0.02). In 51 patients in whom the carbonate content of apatite could be measured, carbonate in the apatite was weakly predictive of positive stone culture with an optimal cutoff value of 13.5 % carbonate (sensitivity 0.61, specificity 0.80). In positive cultures of stones (all mineral types combined), organisms that characteristically produce urease were present in 71 % of the cases, with no difference in this proportion among different types of stone. In summary, the type of mineral in the stone was predictive of positive stone culture, but this correlation is imperfect, as over half of non-struvite, non-apatite stones were found to harbor culturable organisms. We conclude that mineral type is an inadequate predictor of whether a stone contains infectious organisms, and that stone culture is more likely to provide information useful to the management of patients undergoing PCNL.

Topics: Apatites; Humans; Kidney Calculi; Magnesium Compounds; Nephrostomy, Percutaneous; Phosphates; Retrospective Studies; Struvite; Urinary Tract Infections

Topics: Acid-Base Equilibrium; Adult; Calcium Oxalate; Calcium Phosphates; Cystinuria; Diagnosis, Differential; Feeding Behavior; Guideline Adherence; Humans; Hyperuricemia; Kidney Calculi; Magnesium Compounds; Male; Phosphates; Prescription Drugs; Recurrence; Risk Factors; Struvite; Urinary Tract Infections; Water-Electrolyte Balance

The composition of urinary stones in children depends on socioeconomic conditions, geography and dietary habits. Pediatric urolithiasis remains endemic in developing countries. The aim of this study was to analyze stone composition in an Egyptian patient population.. We analyzed prospectively urinary stones from 100 consecutive children (73 males, 27 females), aged 14 months to 12 years. The stones were located in the upper urinary tract in 78%, lower urinary tract in 19% and both in 3%. Male patients had more lower urinary tract stones. On presentation 67% had flank pain and 37% had hematuria. Stones were treated by open surgery in 69% of patients, shockwave lithotripsy in 20% and endoscopic extraction in 13%.. The components of the upper urinary tract calculi were calcium oxalate (47%), ammonium acid urate (26%) and calcium carbonate (21%), whereas the main components of the lower urinary tract calculi were ammonium acid urate (27.2%), struvite (27.2%) and calcium carbonate (22.7%). Urinary tract infection was involved in the development of one third of the stones. Endemic stones were present in 17% of patients, and stones of metabolic origin in 15%. The etiology of stone formation remained unknown in one third of patients.. The epidemiological profile of urinary stones in Egyptian children can now be considered intermediate between developing countries where dietary deficiencies are the main causes and developed countries where infectious and metabolic calculi are observed.

Topics: Calcium Carbonate; Calcium Oxalate; Calcium Phosphates; Child; Child, Preschool; Egypt; Female; Humans; Infant; Lithotripsy; Magnesium Compounds; Male; Phosphates; Prospective Studies; Sex Distribution; Struvite; Uric Acid; Urinary Calculi; Urinary Tract Infections; Urologic Surgical Procedures

The aim of this study is to assess the clinical and biological characteristics of renal stone disease among children living in the coastal region of Tunisia. This retrospective multi-center study included 100 children under the age of 16 years, who presented with urinary stones. The patients' charts were reviewed with regard to age at diagnosis, sex, history and physical examination as well as laboratory and radiologic findings. Stone analysis was performed by infrared spectrophotometry. The male/female sex ratio was 1.5 to 1. The clinical presentation of this pathology was dominated by dysuria. Stones were located in the upper urinary tract in 76 cases (76%). A total of 13% of the study subjects had positive urine cultures. Metabolic investigations were performed in all patients and were normal in 80 cases. Whewellite (calcium oxalate) was found in 77 stones (77.0%). Stone section was made of whewellite in 69.0% of cases and ammonium urate in 47.0%. Struvite stones were more frequently seen in the lower urinary tract. Our study suggests that the epidemiological profile of renal stones in Tunisia has changed towards a predominance of calcium oxalate stones and upper tract location. Also, the male predominance of pediatric urolithiasis is becoming less obvious in Tunisia.

Topics: Abdominal Pain; Adolescent; Calcium Oxalate; Child; Child, Preschool; Dysuria; Female; Flank Pain; Humans; Infant; Magnesium Compounds; Male; Phosphates; Physical Examination; Retrospective Studies; Sex Distribution; Spectrophotometry, Infrared; Struvite; Tunisia; Uric Acid; Urinary Calculi; Urinary Tract Infections; Urolithiasis

To derive hardness factors for crystal phases of urinary tract stones and describe the hardness pattern in a stone population.. In a retrospective study, recordings from patients treated with extracorporeal shock-wave lithotripsy (ESWL) (stone surface area < or = 100 mm2) were used to derive hardness factors. The number of re-treatments, the number of shock waves and the energy index (the voltage in kilovolts multiplied by the number of shock waves) required for a satisfactory stone disintegration were assumed to reflect the hardness. The stone composition in 2100 patients provided the basis for an average hardness pattern. A hardness index was calculated from the fraction of each crystal phase and its hardness factor.. The hardness factors were as follows: calcium oxalate monohydrate, 1.3; calcium oxalate dehydrate, 1.0; hydroxyapatite, 1.1; brushite, 2.2; uric acid/urate, 1.0; cystine, 2.4; carbonate apatite, 1.3; magnesium ammonium phosphate, 1.0; and mixed infection stones, 1.0. The hardness index for 114 stones (surface area 100-200 mm2) corresponded reasonably well to the ESWL treatment efforts. Calcium oxalate monohydrate, calcium oxalate dihydrate and hydroxyapatite were the most frequently encountered crystal phases in all 2100 stones. Only 21% of the stones were composed of only one crystal phase. There were two, three and more than three crystal phases in 26%, 38% and 15% of the stones, respectively. The hardness index calculated for 2100 stones ranged between 0.70 and 2.33, with a mean (SD) of 1.18 (0.15).. The hardness factors and hardness index derived in this study might be useful for describing the stone situation in individual patients and groups of patients and for comparison of various treatment strategies.

Topics: Apatites; Calcium Oxalate; Calcium Phosphates; Cystine; Durapatite; Hardness; Humans; Lithotripsy; Magnesium Compounds; Phosphates; Retrospective Studies; Struvite; Uric Acid; Urinary Calculi; Urinary Tract Infections

Any material placed in the urinary tract is susceptible to the formation of encrustations of crystalline bacterial biofilms. These biofilms cause severe complications in some cases. The strategies used so far for reduction of these complications by surface modifications of the implant material failed to show the expected results.. In this study, we investigated amorphous carbon coatings (a-C:H) for their ability to effectively reduce or to repress the progressive formation of infection-enhancing crystalline biofilms as new functional surface coatings. In nine patients suffering for several years from stenting, a-C:H-coated ureteral stents were tested in treatment attempts. The current replacement intervals amounted to a mean of 77 days; the principle cause for early replacement was massive stent encrustations associated with symptomatic urinary tract infections.. In total, 20 coated ureteral stents were tested spanning indwelling times between 3 and 4 months. No stent-related complications occurred. In all cases extraordinarily facile handling, less pain during replacement, and markedly increased tolerance were observed. Symptomatic urinary tract infections were reduced by more than 50%. The stents remained virtually free of encrustations.. a-C:H coatings are a novel strategy leading to an enhancement of long-term applicability of ureteral stents and catheters and to improved patient comfort.

Topics: Adult; Aged; Biofilms; Carbon; Coated Materials, Biocompatible; Crystallization; Female; Follow-Up Studies; Humans; Magnesium Compounds; Male; Middle Aged; Phosphates; Prosthesis Design; Prosthesis Failure; Risk Factors; Stents; Struvite; Ureteral Obstruction; Urinary Tract Infections

Individuals with struvite uroliths are susceptible to recurrent urinary tract infections (UTI), sepsis, and renal disease. Unfortunately, little is known about the host-specific factors that predispose to this disease. In order to develop a rodent model that can address this problem, we inoculated female Fischer 344 (F344), Lewis (LEW), Sprague-Dawley (SD), and Wistar (WIS) rats with a host-adapted strain of Ureaplasma parvum. Animals were necropsied at 2 weeks postinoculation; 100% of F344, 42% of SD, 10% of LEW, and 10% of WIS rats remained infected. Severe bladder lesions and struvite calculi were seen in 64% of F344 rats; in other rat strains, bladder lesions were mild or absent. F344 rats with struvite uroliths had the highest urinary levels of proinflammatory cytokines, such as GRO/KC, interleukin-1alpha (IL-1alpha), and IL-1beta. F344 rats without struvite stones at necropsy had milder bladder lesions and significantly lower urinary levels of proinflammatory cytokines but a more prominent inflammatory response than did other rat strains. Based on our results, struvite stone formation is linked to a robust inflammatory response that does not resolve UTI but instead promotes damage to surrounding tissues.

Topics: Animals; Antibody Formation; Cytokines; Disease Susceptibility; Female; Magnesium Compounds; Phosphates; Rats; Rats, Inbred Strains; Struvite; Ureaplasma; Ureaplasma Infections; Urinary Calculi; Urinary Tract Infections

On 27 January 2000, a struvite calculus was observed in the vagina during necropsy of a 138-cm-long female bottlenose dolphin (Tursiops truncatus) collected from the Stono River, South Carolina (USA). Vaginal calculi have been reported in other species of cetaceans but not in bottlenose dolphins. Urinary tract infection might have been an underlying cause of the calculus. While urinary tract inflammation was not detected by light microscopic evaluation of sections of the urinary tract, it is conceivable that sufficient time had lapsed following voiding of the calculus through the urethra for urinary tract infection to have resolved. To further define the prevalence and significance of urolithiasis, prosectors of dead stranded marine mammals are encouraged to closely observe their urinary and genital tracts for calculi and to submit them for quantitative analysis.

Topics: Animals; Dolphins; Female; Magnesium Compounds; Phosphates; Struvite; Urinary Calculi; Urinary Tract Infections; Vagina

To elucidate the factors contributing to staghorn stone formation in patients.. The records of 82 patients (44 men and 38 women) with complete staghorn calculi were reviewed retrospectively for clinical presentation, metabolic disturbances and anatomical abnormalities.. There were 79 unilateral and three bilateral cases. The patient performance of the activities of daily life was assessed with the modified Rankin scale (MRS) and it was found that 69 patients were functionally independent (84.1%, MRS 0-1) and 10 patients had a severe disability (12.2%, MRS 4-5). Seven patients had chronic indwelling catheters (8.5%). A positive urine culture was found in 24.4% of patients. Analysis of stone composition revealed magnesium ammonium phosphate and mixed calcium oxalate-phosphate were the most frequently identified types of stone (32.1% and 22.2%, respectively). Urinary pH was low in patients with uric acid stones (mean 5.4). Hyperuricemia, cystinuria and hypercalciuria were found in 14.6%, 2.4% and 37.8%, respectively. Hypercalciuria was found more frequently in calcium-stone cases. Eleven patients (13.4%) showed structural abnormalities of the kidney.. Our data show that the patients with severe disability, urinary tract infection and hypercalciuria could be recognized more frequently in staghorn calculi compared with common urolithiasis. However, in Western countries, the frequency of both urinary tract infection and struvite stones is much higher than in our data. Other Japanese authors have also reported the low frequency of struvite stones in staghorn calculi, suggesting that various factors other than urinary tract infection possibly contribute to the formation of staghorn calculi in Japan.

Topics: Activities of Daily Living; Adult; Aged; Calcium; Calcium Oxalate; Calcium Phosphates; Catheters, Indwelling; Cystinuria; Female; Humans; Hydrogen-Ion Concentration; Hyperuricemia; Kidney; Kidney Calculi; Magnesium Compounds; Male; Middle Aged; Phosphates; Retrospective Studies; Struvite; Uric Acid; Urinary Tract Infections; Urine

Massive urolithiasis of the penile urethra was observed in an adult pygmy sperm whale (Kogia breviceps) stranded on Topsail Island, North Carolina, USA. Calculi occupied the urethra from just distal to the sigmoid flexure to the tip of the penis for a length of 43 cm. A urethral diverticulum was present proximal to the calculi. The major portion of the multinodular urolith weighed 208 g and was 16 cm long x 3.7 cm diameter at the widest point. The urolith was composed of 100% struvite (magnesium ammonium phosphate) and on culture yielded Klebsiella oxytoca, a urease-positive bacterium occasionally associated with struvite urolith formation in domestic animals. Reaction to the calculi was characterized histologically by moderate multifocal to coalescing plasmacytic balanitis and penile urethritis. Role of the urethrolithiasis in the whale's stranding is speculative but could have involved pain or metabolic perturbations such as uremia or hyperammonemia.

Topics: Animals; Fatal Outcome; Klebsiella Infections; Klebsiella oxytoca; Magnesium Compounds; Male; Phosphates; Struvite; Urethra; Urinary Calculi; Urinary Tract Infections; Whales

An 8-year-old, female spayed miniature schnauzer was presented for pollakiuria and gross hematuria. Infection-induced struvite urolithiasis with concurrent bacterial urinary tract infection was diagnosed. The treatment is described, followed by a brief discussion of struvite stones and their medical management.

Topics: Animals; Anti-Bacterial Agents; Cephalexin; Diagnosis, Differential; Diet; Dogs; Female; Magnesium Compounds; Pedigree; Phosphates; Radiography; Struvite; Urinary Bladder Calculi; Urinary Tract Infections

Infection stones make up approximately 15% of urinary stone diseases and are thus an important group. These stones are composed of struvite and/or carbonate apatite. The basic precondition for the formation of infection stones is a urease-positive urinary tract infection. Urease is necessary to split urea into ammonia and CO(2). As a result, ammonia ions can form and at the same time alkaline urine develops, both being preconditions for the formation of struvite and carbonate apatite crystals. When these crystals are deposited infection stones form. Pathogenetically, various risk factors play a role: urinary obstruction, neurogenic bladder, dRTA, and MSK. If these infections are not treated and the stones are not removed, the kidney will be damaged. Modern methods are available for stone removal, e.g., ESWL and/or instrumental urinary stone removal. Here, especially less invasive methods are preferable. Any treatment must be adjusted to the patient individually. Patients should be examined frequently for recurrent urinary tract infections and stone recurrences, and new infections must be resolutely treated. Good therapy and prophylaxis are possible with present-day treatment modalities.

Topics: Apatites; Bacteria; Comorbidity; Humans; Hydrogen-Ion Concentration; Magnesium Compounds; Phosphates; Risk Factors; Struvite; Urease; Urinary Calculi; Urinary Tract Infections; Urography

This study was performed to look for an improvement of therapeutic strategies with regard to the treatment of infectious urinary stones using artificial stones made of struvite and apatite ('Bon(n) stones') which are comparable to their natural counterparts.. Using an experimental arrangement simulating the physiological conditions in the upper urinary tract, the efficacy of artificial urine (pH 5.7), Suby G solution (pH 3.6), mixtures of artificial urine with Suby G (pH 3.9 and pH 4.1) in dissolving artificial struvite and apatite stones (Bon(n) stones) was investigated. The dissolution of natural infectious urinary stones was also measured. Additionally, investigations on shock-wave lithotripsy (SWL) combined with initial chemolytic treatment of the stones were performed.. The efficacy of Suby G solution in dissolving artificial stones was demonstrated. Direct comparison of chemolysis of natural and artificial stones showed no statistical difference between infectious urinary stones and Bon(n) stones of the same material. The investigations on SWL showed a significant improvement on stone comminution, especially of artificial apatite stones after initial chemolytic treatment with Suby G.. New basics to improve dissolution of infectious urinary stones have been developed by performing standardized in vitro investigations. Local chemolysis with Suby G is an effective tool in the treatment of infectious stone disease. SWL can be improved by varying the physical properties of infectious stones through initial treatment with Suby G solution.

Topics: Apatites; Equipment Design; In Vitro Techniques; Lithotripsy; Magnesium Compounds; Models, Biological; Phosphates; Sensitivity and Specificity; Solvents; Statistics, Nonparametric; Struvite; Urinary Calculi; Urinary Tract Infections

In this paper, the clinical and metabolic patterns of nephrolithiasis in different ages of adulthood are studied.. Eight-hundred patients observed at the Mauriziano Hospital between 1990 and 1995, were classified into 3 groups, on the basis of age at the onset of disease: A: 20 through 39 years; B: 40 through 59; C: 60 years and over.. Calcium-oxalate stones had a lower recurrence in C (19.1%) and B (31.5%) than in A (41.7%). Pure uric acid stones recurred in 18.9% of C, 16.7% of B and 4.3% of A. The prevalence of hypercalciuria was higher in A (50.3%) than in B (35.9%) and C (36%); so did hypocitraturia. Hyperuricuria was lower in A (5%, p < 0.05) than in B (9.4%) and C (10%). Low urine pH (< 5.5) was 13% in A, 21.3% in B, 38% in C. Prevalence of hyperoxaluria was about 14% in all groups. The whole prevalence of secondary forms of stone disease was 13% in A, 12% in B and 30% in C. Differences among groups were mainly due to prevalence of urological abnormalities and urinary tract infection. In patients without metabolic disturbances. urological abnormalities or urinary tract infections altogether, were 4.6% in A; 5.2% in B; 33% in C. Urological approach removed 8% of stones in A, 5.6% in B and 10.2% in C.. Higher morbidity in younger patients could be due to a lower prevalence of easier-passing uric acid stones. The higher occurrence of urological disturbances and struvite stones in the elderly could explain the higher morbidity in this group.

Topics: Adult; Age of Onset; Aged; Calcium; Calcium Oxalate; Calcium Phosphates; Citric Acid; Comorbidity; Female; Humans; Hydrogen-Ion Concentration; Kidney Calculi; Kidney Function Tests; Magnesium Compounds; Male; Middle Aged; Oxalic Acid; Phosphates; Prevalence; Pyelonephritis; Recurrence; Retrospective Studies; Struvite; Uric Acid; Urinary Tract; Urinary Tract Infections

Struvite precipitation and urease activity were studied in 72 bacterial strains isolated from patients with an urinary infection. The results revealed struvite precipitation by urease-positive, urease-negative and weakly urealitic bacteria. However, in some strains of each of these groups, no precipitation was observed. Variations in pH within the cultures were also investigated as were the mineralogy and morphology of the crystals precipitated using X-ray diffraction and scanning electron microscopy, respectively. The role of urease activity and alkalinization of the medium in struvite precipitation is discussed, as is the possible involvement of bacteria in nucleation processes. We concluded that urease-negative bacteria or those with weak urease activity may also be involved in the formation of struvite renal calculi although urease-positive bacteria seem to make a greater contribution.

Topics: Chemical Precipitation; Crystallization; Humans; Hydrogen-Ion Concentration; Kidney Calculi; Magnesium Compounds; Microscopy, Electron, Scanning; Phosphates; Struvite; Urease; Urinary Tract Infections

Ureaplasma urealyticum is a fastidious organism which is not recovered by conventional bacterial cultures techniques, but special cultures are required for its isolation and identification. As it is a urease-producing organism, it is considered a risk factor for the formation of struvite calculi in the urinary tract. A total of 30 patients with urinary infection stones (19 of them with the 1st formation and 11 with recurrent stone formation) were included in the study. Both bladder urine specimen (cystoscopically obtained) and stones removed were subjected to conventional cultures and also to Ureaplasma specific cultures (A7 agar and U9 broth). The results of culture techniques revealed that 86.7% of patients had aerobic organisms (E. coli in 46.7%, Klebsiella in 30%, Proteus in 6.7% and Pseudomonas in 3.3%) and 26.7% showed U. urealyticum in mid stream urine. As regards stone cultures, they revealed aerobic organisms in 76.7%, and U. urealyticum in 20%. Sensitivity tests for U. urealyticum showed that minocycline was the most effective antimicrobial followed by tetracycline and ciprofloxacin. From these data, we conclude that U. urealyticum may be the causative organism for infection stone and should be searched for via its specific cultures, especially in patients with recurrent stones and with the so-called sterile pyuria.

Topics: Adult; Anti-Bacterial Agents; Apatites; Bacterial Typing Techniques; Calcium Oxalate; Causality; Cystoscopy; Drug Therapy, Combination; Egypt; Female; Humans; Hydroxamic Acids; Magnesium Compounds; Male; Microbial Sensitivity Tests; Phosphates; Recurrence; Struvite; Ureaplasma Infections; Ureaplasma urealyticum; Urinalysis; Urinary Calculi; Urinary Tract Infections

The stones removed from 273 patients (220 males, 53 females) with bladder stones and 27 patients with urethral stones (males) were analyzed by infrared spectroscopy. Of these stones 50.0% contained magnesium ammonium phosphate (MAP), 39.9% calcium (oxalate and/or phosphate), 9.4% uric acid (urate), and 0.7% cystine. The disorders associated with bladder stones were prostatic hyperplasia and cancer (47.8%), neurogenic bladder (11.8%), urethral stricture (3.6%) and so on in males, and neurogenic bladder (48.1%), after operation of uterus (29.0%), bladder cancer (5.7%) and so on in females. Urinary infections were complications in 59.3% of patients with MAP stones, 41.2% with urate stones and 20.0% with calcium stones. The most often isolated bacteria from the infected urine were of the Proteus species.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Bacteriuria; Calcium Oxalate; Calcium Phosphates; Chi-Square Distribution; Child; Child, Preschool; Cystine; Female; Humans; Magnesium Compounds; Male; Middle Aged; Phosphates; Prostatic Hyperplasia; Spectrophotometry, Infrared; Struvite; Urethral Diseases; Uric Acid; Urinary Bladder Calculi; Urinary Bladder, Neurogenic; Urinary Calculi; Urinary Tract Infections; Urologic Diseases

Topics: Chronic Disease; Humans; Kidney Calculi; Magnesium Compounds; Male; Middle Aged; Phosphates; Proteus Infections; Struvite; Urinary Tract Infections

Of 100 renal units which were made stone-free by percutaneous stone extraction in 1985, 86 (86.0%) were re-examined radiologically up to 5 years after operation. The re-examination was performed because of symptoms or as part of a regular check-up or after calling the patient. Intrarenal calcifications were diagnosed in 27 of 86 (31.4%) of the renal units, but only in 11 (12.8%) were there stones requiring treatment.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Calcium Oxalate; Calcium Phosphates; Cystinuria; Female; Follow-Up Studies; Humans; Kidney Calculi; Lithotripsy; Magnesium; Magnesium Compounds; Male; Middle Aged; Nephrostomy, Percutaneous; Phosphates; Radiography; Radioisotope Renography; Recurrence; Struvite; Urinary Tract Infections

Topics: Corynebacterium Infections; Humans; Kidney Calculi; Magnesium; Magnesium Compounds; Phosphates; Struvite; Urinary Tract Infections

A total of 28 patients with extensive struvite staghorn calculi underwent endourological sandwich therapy consisting of primary percutaneous debulking followed by extracorporeal shock wave lithotripsy (ESWL*) of residual stone fragments. Secondary percutaneous procedures, ESWL treatments and 10% hemiacidrin irrigations were used as necessary specifically to achieve a stone-free renal unit. With 12 to 55 months (mean 31 months) of followup, during which time regular surveillance was done and antibiotic prophylaxis was used routinely, renal function remained stable or improved in 93% of the patients, including 4 with a solitary kidney. Infection has recurred or persisted in 30% of the patients, while stones recurred in 22%. We conclude that an aggressive, combined endourological approach to the management of struvite staghorn calculi can achieve long-term results comparable to standard operative intervention.

Topics: Combined Modality Therapy; Creatinine; Follow-Up Studies; Humans; Kidney Calculi; Lithotripsy; Magnesium; Magnesium Compounds; Phosphates; Recurrence; Struvite; Time Factors; Urinary Tract Infections

Struvite stones are caused by urea-splitting, usually gram-negative, organisms. A case of aggressive struvite stone production caused by Corynebacterium group F1 is reported that responded to the appropriate antibiotic treatment. To our knowledge this organism has never been associated previously with struvite stone formation.

Topics: Adult; Corynebacterium Infections; Humans; Kidney Calculi; Magnesium; Magnesium Compounds; Male; Phosphates; Struvite; Urinary Tract Infections

After feeding various diets we studied the effects of dietary calcium, magnesium and phosphorus on the formation of struvite stones in rats with urinary tract infections, and also studied the effects of the administration of vitamin D3 and aluminium gel on stone formation. A low-magnesium diet decreased urinary magnesium and prevented stone formation, but a medium-calcium diet did not significantly decrease stone weight. A high-calcium diet decreased urinary phosphorus and inhibited stone formation. A high-calcium and high-phosphorus diet decreased urinary excretion of magnesium and inhibited stone formation. Although the administration of vitamin D3 did not inhibit stone formation, aluminium gel decreased the urinary level of phosphorus and prevented stone formation. A marked decrease in urinary magnesium and/or phosphorus may prevent struvite stone formation in rats with urinary tract infections.

Topics: Aluminum; Animals; Calcium, Dietary; Cholecalciferol; Magnesium; Magnesium Compounds; Male; Phosphates; Phosphorus, Dietary; Proteus Infections; Proteus mirabilis; Rats; Rats, Inbred Strains; Struvite; Urinary Calculi; Urinary Tract Infections

The authors report about 12 cases of long ureteral calculi, 16 to 39 mm in size, observed over 10 years. They were all made of a mixture of ammonium-magnesium phosphate and calcium phosphocarbonate. Infection was the revealing symptom, either in the form of simple bacteriuria or as acute pyelonephritis or sepsis. These calculi, found in a lumbar or pelvic location, were very long, radiopaque but with a moderate radiological density, homogeneous and have regular contours. They were straight, sometimes slightly bent, rarely (one case out of 12) arciform. In 11 of 12 cases, the affected patient was female. In most cases, the urine was infected by Proteus mirabilis. In spite of their size, the calculi caused total obstruction in 3 of 12 cases only. They were or were not associated to ipsilateral coral calculi of the same chemical type. Destruction was easily achieved with physical agents. The etiological, radiological and therapeutic characteristics of these calculi give them a specific place among ammonium-magnesium phosphate calculi.

Topics: Adult; Aged; Aged, 80 and over; Calcium Carbonate; Female; Hemostatics; Humans; Lithotripsy; Magnesium; Magnesium Compounds; Male; Middle Aged; Phosphates; Proteus Infections; Proteus mirabilis; Radiography; Struvite; Ureteral Calculi; Ureterostomy; Urinary Tract Infections

We reviewed 53 patients with infection stones treated by extracorporeal shock wave lithotripsy (ESWL*) monotherapy to determine the long-term rate free of stones and the stone recurrence rate as correlated with the pre-treatment stone burden and the radiological presence of sand or fragments after the procedure. Long-term followup (mean 26.6 months) was available on 33 patients representing 38 kidneys. Although only 3 kidneys were free of stones immediately after ESWL, 20 were without stones at 3 months and 18 (47%) were stone-free at followup. Of 9 kidneys with fragments of more than 5 mm. after the final treatment 7 (78%) had residual fragments at 3 months and experienced stone progression. Of 9 kidneys with sand remaining 6 (66%) and all 3 kidneys that appeared to be free of stones after ESWL were without stones at followup. The 3-month plain film of the kidneys, ureters and bladder was a reliable indicator of eventual outcome. Of 20 kidneys that were free of stones at 3 months 16 remained without stones. Of 18 kidneys with residual stone particles at 3 months 14 showed disease progression, 2 had stable disease and 2 passed residual sand. Only 1 of 17 patients who were free of stones or had stable stone disease had a positive urine culture at followup. Patients with infection stone fragments 3 months after ESWL monotherapy have a high rate of stone progression (78%) and should undergo further treatment. ESWL monotherapy of infection stones requires close patient followup to assure that all residual fragments have passed and urine remains sterile.

Topics: Adult; Aged; Apatites; Female; Follow-Up Studies; Humans; Kidney Calculi; Lithotripsy; Magnesium; Magnesium Compounds; Male; Middle Aged; Phosphates; Radiography; Retrospective Studies; Struvite; Urinary Tract Infections

Struvite urolithiasis forms as a consequence of a urinary tract infection by urease-producing species of bacteria such as Proteus mirabilis. Ammonia, produced by the enzymatic hydrolysis of urea, elevates urine pH causing a supersaturation and precipitation of Mg++ as struvite (NH4MgPO4). Calcium often precipitates as well, forming the mineral carbonate-apatite (Ca10(PO4)6CO3). We have developed a procedure based on direct observation by light microscopy whereby struvite crystal growth can be quickly monitored in response to chemical changes in urine. As struvite crystals assume a characteristic shape or crystal habit based on their growth rate, the effect of urine chemistry and the action of various crystallization or urease inhibitors on struvite formation can be quickly shown. In addition preliminary effects of alkaline pH, or the presence of toxic compounds on bacteria can also be shown through their loss of motility.

Topics: Crystallization; Humans; In Vitro Techniques; Magnesium; Magnesium Compounds; Microscopy, Phase-Contrast; Phosphates; Proteus Infections; Proteus mirabilis; Struvite; Urinary Calculi; Urinary Tract Infections

The efficacy of a diet designed to facilitate dissolution of feline magnesium ammonium phosphate (struvite) uroliths was evaluated in 30 cases of urolithiasis, sterile struvite uroliths dissolved in a mean of 36 days after initiation of dietary treatment. In 5 cases of urolithiasis, struvite urocystoliths associated with urease-negative bacterial urinary tract infection dissolved in a mean of 23 days after initiation of dietary and antimicrobial treatment. In 3 cases of urolithiasis, struvite urocystoliths associated with urease-positive staphylococcal urinary tract infection dissolved in a mean of 79 days after initiation of dietary and antimicrobial treatment. Dissolution of uroliths in cats fed the treatment diet was associated with concomitant remission of dysuria, hematuria, and pyuria, and reduction in urine pH and struvite crystalluria. In one case, a urocystolith composed of 100% ammonium urate, and in another case, a urolith composed of 60% calcium phosphate, 20% calcium oxalate, and 20% magnesium ammonium phosphate did not dissolve.

Topics: Amoxicillin; Amoxicillin-Potassium Clavulanate Combination; Animals; Cat Diseases; Cats; Clavulanic Acids; Drug Therapy, Combination; Female; Follow-Up Studies; Hydrogen-Ion Concentration; Magnesium; Magnesium Compounds; Male; Phosphates; Radiography; Recurrence; Specific Gravity; Struvite; Time Factors; Urinary Calculi; Urinary Tract Infections

The surfaces of 32 encrusted urinary catheters were examined by scanning electron microscopy to investigate the association of bacteria with the encrusting deposits. Deposits consisted of struvite crystals surrounded by aggregates of very small crystallites of hydroxyapatite. Underneath these minerals there was a layer of closely packed bacteria. Impressions of bacteria were also observed in hydroxyapatite. Crystals were often engulfed by the bacterial layer, which thus appeared to bind the crystals to each other and to the catheter surface. This thick layer of bacteria associated with crystals may protect both the bacteria from antibiotics and the crystals from acidic bladder washout solutions intended to dissolve them. Furthermore, the existence of this sessile population explains why urease-producing bacteria are not invariably detected in the urine of patients with encrusted catheters. The observation of this bacterial layer (or "biofilm") by scanning electron microscopy provided direct evidence for infection being implicated in catheter encrustation.

Topics: Bacterial Adhesion; Catheters, Indwelling; Crystallization; Durapatite; Humans; Hydroxyapatites; Magnesium; Magnesium Compounds; Microscopy, Electron, Scanning; Phosphates; Struvite; Urinary Catheterization; Urinary Tract Infections

We have studied retrospectively 68 children who presented with urolithiasis between 1965 and 1986. Male to female ratio was 1.83 to 1 and the mean age was 9.5 years. Fifty four children (79%) had calculi in the upper urinary tract, 9 (13%) had in the lower, and 4 (6%) had calculi both in the upper and lower urinary tract. The most common presenting symptoms were gross hematuria (53%) and abdominal or flank pain (38%). Predisposing factors could be found only in 21 children (31%). Twenty four of the 68 patients (35%) had open surgery and 16 patients (24%) passed their stones spontaneously. Twenty one stones were analyzed by infrared spectroscopy. Infectious stone was more frequent than in adult cases. Among children five years old and younger, infectious stone was the most frequent. Among children over five years old, the number of idiopathic calcium stone has been on the increase with the years.

Topics: Adolescent; Apatites; Calcium Oxalate; Child; Child, Preschool; Female; Humans; Infant; Magnesium; Magnesium Compounds; Male; Phosphates; Struvite; Urinary Calculi; Urinary Tract Infections

Mid-shaft specimens were cut from latex catheters coated with a modified hydrogel, latex catheters coated with silicone elastomer, and 100% silicone catheters. These specimens were subjected to controlled in vitro encrustation conditions. During a test period of 11 weeks, there was no significant difference in the quantities of encrusting deposits formed on the three materials.

Topics: Catheters, Indwelling; Crystallization; Humans; Hydrogel, Polyethylene Glycol Dimethacrylate; In Vitro Techniques; Magnesium; Magnesium Compounds; Phosphates; Polyethylene Glycols; Rubber; Silicone Elastomers; Silicones; Struvite; Urinary Catheterization; Urinary Tract Infections

29 patients suffering from recurrent struvite stones and/or persistent urinary tract infection were analyzed retrospectively with a follow-up time of 10 +/- 6 years. A sanitation of the urease-positive urinary tract infection was possible in 12 patients (41%). After 10 out of 53 operations (19%) rest stones were found. An unilateral nephrectomy was done in 3 cases. Despite rest calculi and persistent urinary tract infection no further calculus growth or deterioration of renal function was found in most patients.

Topics: Combined Modality Therapy; Female; Follow-Up Studies; Humans; Kidney Calculi; Kidney Failure, Chronic; Magnesium; Magnesium Compounds; Male; Middle Aged; Nephrectomy; Phosphates; Postoperative Complications; Recurrence; Retrospective Studies; Struvite; Urinary Tract Infections

During a seven-year period (1975-1981) a total of 1325 patients hospitalized for stone disease were studied as to the occurrence of positive urine cultures. Urinary stones from 535 surgically treated patients were analyzed with infrared spectrophotometry and the relationships between stone composition, level of surgery and bacteriological strains were studied. Positive urinary cultures were found in 34% of the surgically treated patients and in 21% of those not operated upon. Among the surgically treated patients with urinary tract infection (UTI) E. coli was the most frequent microorganism (35%), followed by Proteus (28%). Patients with Proteus infection had the highest frequency of UTI episodes, most of which occurred before hospitalization. There was a higher frequency of magnesium ammonium phosphate (MAP) calculi among patients with Proteus infection than among those with non-Proteus infection, in whom no difference in stone composition was found. Patients infected with E. coli had more phosphate-containing stones (CaP+MAP) than non-infected patients. The highest frequency of oxalate calculi (CaOx+CaOx/CaP) was found among patients without infection. No E. coli infections were seen in male patients with CaP and MAP calculi. MAP stones were most often found in the kidney and oxalate stones in the ureter.

Topics: Calcium Oxalate; Calcium Phosphates; Escherichia coli Infections; Female; Humans; Kidney Calculi; Magnesium; Magnesium Compounds; Male; Middle Aged; Phosphates; Proteus Infections; Spectrophotometry, Infrared; Struvite; Urinary Tract Infections

Topics: Animals; Disease Models, Animal; Female; Humans; Magnesium; Magnesium Compounds; Male; Phosphates; Rats; Struvite; Urinary Calculi; Urinary Tract Infections

Topics: Enterobacteriaceae Infections; Humans; Hydroxamic Acids; Hydroxyurea; Magnesium; Magnesium Compounds; Phosphates; Pseudomonas Infections; Struvite; Urease; Urinary Calculi; Urinary Tract Infections

Topics: Adult; Aged; Anti-Bacterial Agents; Drug Therapy, Combination; Female; Humans; Hydrogen-Ion Concentration; Hydroxamic Acids; Kidney Calculi; Magnesium; Magnesium Compounds; Male; Middle Aged; Phosphates; Struvite; Urease; Urinary Tract Infections

Topics: Adult; Anti-Infective Agents, Urinary; Calcium Oxalate; Female; Humans; Hydrogen-Ion Concentration; Kidney Calculi; Magnesium; Magnesium Compounds; Male; Mandelic Acids; Methenamine; Middle Aged; Phosphates; Proteus Infections; Struvite; Urinary Tract Infections

A case of soft vesical calculi is reported. A 72-year-old male, visited our clinic complaining of discharge of white muddy substance. KUB film revealed calcification in the vesical region. Urinalysis showed UTI, and culture of urine was positive for Proteus mirabilis. Thereafter, the patient suffered from discharges of similar calculi several times. Two of three infrared spectroscopic charts showed mixture of calcium phosphate and ammonium hydrogen urate and that of the remaining disclosed magnesium ammonium phosphate. An alcian blue-PAS double staining of this calculus revealed the presence of acid and neutral glycosaminoglycans, and bacterial colonies. These calculi were thought to be different from the so called 'matrix calculi'.

Topics: Aged; Calcium Phosphates; Glycosaminoglycans; Humans; Magnesium; Magnesium Compounds; Male; Phosphates; Proteus Infections; Proteus mirabilis; Radiography; Struvite; Uric Acid; Urinary Bladder Calculi; Urinary Tract Infections

The use of drugs inhibiting bacterial urease represents an interesting improvement in preventive treatment of renal infected stones. The low dose (120 mg/day) for one week followed by 60 mg/day of propionohydroxamic acid (PHA) has shown excellent anti-urease activity. The nearly normal absence of side effects also allows long-term administration.

Topics: Humans; Hydroxamic Acids; Kidney Calculi; Magnesium; Magnesium Compounds; Phosphates; Struvite; Urinary Tract Infections

With advanced techniques of scanning and transmission electron microscopy we studied the ultrastructural ecology of bacteria associated with struvite calculi on catheter surfaces, and in the bladder, ureter and renal pelvis. These detailed morphological data indicate that the interstices, core and external surface of such struvite aggregates contain large numbers of bacterial cells that grow as microcolonies and thick biofilms within extensive fibrous organic matrices. These bacterial cells and their secreted products (glycocalyx or biofilm matrix) appear to provide initial foci for crystal development and aggregation of crystals to form macroscopic struvite stones. The protective glycocalyx-enclosed microcolonial mode of bacterial growth also may explain the relative resistance to antibiotics observed in bacteria associated with infection stones.

Topics: Bacterial Infections; Crystallization; Glycoproteins; Humans; Magnesium; Magnesium Compounds; Microscopy, Electron; Microscopy, Electron, Scanning; Phosphates; Polysaccharides; Struvite; Urinary Calculi; Urinary Tract Infections

Renal stone disease is a common problem in patients with spinal cord injury. The factors responsible are thought to include hypercalciuria and chronic urinary infection. There have, however, been no comparative studies of urinary composition in patients with neuropathic bladder with and without renal stone disease. Blood, 24-h urine samples and circadian variation of urinary composition were studied in male paraplegic patients with renal stone disease accompanied by urinary infection and in similar patients without stone disease with and without urinary infection. Two categories of stone patients were recognised, according to whether or not urinary oversaturation with magnesium ammonium phosphate occurred. The urine of all stone patients was oversaturated with calcium phosphate for part of each day. Urinary calcium was elevated in 16% and plasma urate in 30% of the paraplegics studied.

Topics: Adolescent; Adult; Aged; Calcium; Circadian Rhythm; Humans; Hydrogen-Ion Concentration; Kidney Calculi; Magnesium; Magnesium Compounds; Male; Middle Aged; Paraplegia; Phosphates; Struvite; Urinary Tract Infections

To study the process of formation of staghorn calculi, 58 patients with staghorn calculi were evaluated clinically and the removed stones were studied architecturally. Of 35 patients with infection stones composed of struvite and/or apatite in the nuclei as well as peripheral layers, 18 had identified predisposing factors related to infection. Of 13 patients with infection stones containing calcium oxalate in the nuclei, 7 had predisposing factors of infection but only 2 had metabolic disorders. The patients with infection stones who had no predisposing factors may have transient or subclinical abnormalities. Initial stone formation of oxalate may also be one of the predisposing factors of infection. Most of the patients with staghorn calculi composed of uric acid, oxalate and cystine, had metabolic disorders related to these substances. Large numbers of bacteria and large amounts of organic matrix were found extensively within infection stones and were thought to be important components as well as crystals. Metabolic stones contained little matrix. In this case crystal aggregation is thought to play the most important role in stone formation.

Topics: Adolescent; Adult; Aged; Apatites; Calcium Oxalate; Child; Child, Preschool; Cystine; Female; Humans; Infant; Kidney Calculi; Magnesium; Magnesium Compounds; Male; Middle Aged; Phosphates; Struvite; Uric Acid; Urinary Bladder Diseases; Urinary Tract Infections; Vesico-Ureteral Reflux

A newly designed urolithiasis model for rats, inducing a mild urinary tract infection, exhibiting reduced renal damage without pyelonephritis and causing reliable stone formation, was established. This was accomplished by implanting a zinc disc in the bladder and then performing transvesical inoculation of Proteus mirabilis into the bladder. Five days after challenge with 10(7) colony forming units (CFU) of P. mirabilis in each rat, the number of organisms in the bladder urine reached a level of over 10(5) colony forming units per ml. The infection was mostly restricted to the urinary tract organs. Infectious bladder stones were formed 5 days after infection and developed day by day, weighing 88.3 +/- 18.8 mg. on the 21st day. Blood urea nitrogen values stayed in the normal range in all test animals during this experiment. The main composition of the stones formed was shown to be struvite (MgNH4PO4 X 6H2O).

Topics: Animals; Female; Foreign Bodies; Magnesium; Magnesium Compounds; Phosphates; Proteus Infections; Proteus mirabilis; Rats; Rats, Inbred Strains; Struvite; Time Factors; Urinary Bladder; Urinary Bladder Calculi; Urinary Tract Infections; Zinc

We determined the bacteriology of apparently infected renal calculi and accompanying urinary tract infections, and assessed the potential clinical value of the culture results. Twenty-two branched renal calculi from 16 patients were cultured. Fifteen calculi were infected with 1 or more urease-producing gram-negative enteric bacterium, 2 were infected with a urease-producing bacterium and a nonurease-producing organism, and 5 were sterile. Immersion of infected stones in antimicrobial solutions before culture reduced or eliminated surface bacteria but usually did not eradicate bacteria within the stone. The bacteriology of a stone or stones could be predicted on the basis of available urine culture results in only 2 of the 16 cases. These data suggest that branched renal calculi associated with bacteriuria usually are infected but that documentation of infection and identification of the infecting organism require culture of the stone.

Topics: Anti-Bacterial Agents; Apatites; Bacteriuria; Female; Humans; Kidney Calculi; Magnesium; Magnesium Compounds; Male; Methods; Phosphates; Proteus mirabilis; Pseudomonas aeruginosa; Struvite; Urease; Urinary Tract Infections

The stones associated with urinary tract infection were cultured using a method to distinguish between surface contamination and bacteria within the stone. Twenty three of 30 stones (77%) were infected mainly by Proteus mirabilis or Pseudomonas aeruginosa and most were composed of struvite and/or apatite. Most oxalate and uric acid stones were sterile; occasionally the stones with positive culture had a non-urea-splitting bacteria and these were thought to have been infected secondarily. Some infected stones were studied by light microscopy scanning election microscopy and transmission electron microscopy. We found many rods in the interstices of crystals of struvite and apatite extensively from the nucleus to peripheral layers. These findings are important in the prevention and treatment of infection stones.

Topics: Adolescent; Adult; Aged; Apatites; Child; Child, Preschool; Female; Humans; Infant; Magnesium; Magnesium Compounds; Male; Middle Aged; Phosphates; Proteus mirabilis; Pseudomonas aeruginosa; Struvite; Urinary Calculi; Urinary Tract Infections

Topics: Humans; Hydroxamic Acids; Kidney Calculi; Magnesium; Magnesium Compounds; Phosphates; Struvite; Urinary Tract Infections

The administration of 1 mg estradiol every other week for 12 weeks to female rats resulted in a high incidence (about 50%) of bladder stones. Most calculi were struvite, suggesting the predisposition to urinary tract infection. Enterobacteria, staphylococcus and streptococcus were identified as infecting organisms. Metaplasia of the transitional bladder epithelium by estrogen to a stratified or pseudostratified columnar epithelium may be involved in the underlying cause of urinary tract infection.

Topics: Animals; Calcium; Estradiol; Female; Magnesium; Magnesium Compounds; Male; Metaplasia; Phosphates; Rats; Rats, Inbred Strains; Struvite; Urinary Bladder; Urinary Bladder Calculi; Urinary Tract Infections

Effective treatment and prevention of urolithiasis depends on accurate determination of the chemical nature of the uroliths. A widely used qualitative chemical procedure was compared with quantitative crystallographic analysis of 272 canine uroliths. Agreement between the 2 methods was 78%. Qualitative analysis failed to detect 62% of calcium-containing uroliths and 83% of carbonate apatite uroliths. Qualitative analysis gave false-positive results for urates in 55% of cystine uroliths. Mixed uroliths comprising 6% of the total could not be classified without quantitative analysis. Silicate, cystine, and urate uroliths generally were of pure composition. Crystallographic analysis indicated the following distribution of major types: struvite, 69%; calcium oxalate, 10%; urate, 7%; silicate, 3.5%; cystine, 3.2%; calcium phosphate, 1%; and mixed, 6%. Among dogs with struvite uroliths, 66% had positive results of bacterial culturing from the urinary bladder. Six breeds (Miniature Schnauzer, Welsh Corgi, Lhasa Apso, Yorkshire Terrier, Pekingese, and Pug) had a significantly higher risk for urolithiasis, compared with other breeds. The German Shepherd Dog had a significantly lowered risk, compared with other breeds. Two breeds had significant relationship to a specific type of urolith: Miniature Schnauzer for oxalate, and Dalmatian for urate (P less than 0.001). It was concluded that quantitative analysis, using crystallography, was superior for the detection of calcium oxalate, carbonate apatite, cystine, urate, and mixed uroliths.

Topics: Animals; Bacteriuria; Calcium Oxalate; Calcium Phosphates; Crystallography; Cystine; Dog Diseases; Dogs; Female; Magnesium; Magnesium Compounds; Male; Phosphates; Silicic Acid; Struvite; Uric Acid; Urinary Calculi; Urinary Tract Infections

The composition and structure of nuclei of infection stones were investigated. Twenty seven out of 40 renal stones were found to contain struvite and/or carbonate apatite in the nuclei as well as peripheral layers, and 13 contained calcium oxalate. Some bladder stones also contained different substances in the nuclei. In some infection stones whose architecture was studied in thin section and with scanning electron microscopy, we found large numbers of bacteria in the nuclei composed of struvite and/or apatite. Though we could find no bacteria within the nuclear parts composed of oxalate, we found them in apatite layers outside the nuclei. Urea-splitting bacteria are suggested to participate both in the initial formation of struvite stones and in the diversion of oxalate stones into phosphate stones. Such bacteria may play important roles in stone formation, not only as promotors of crystallization of struvite and apatite but also as a component such as of an organic matrix.

Topics: Calcium Oxalate; Calcium Phosphates; Humans; Magnesium; Magnesium Compounds; Microscopy, Electron; Microscopy, Electron, Scanning; Phosphates; Struvite; Urinary Calculi; Urinary Tract Infections

Urolithiasis involving the upper urinary tract is a multifactorial disease that remains a significant health problem. A variety of intrinsic and extrinsic factors influence the incidence of disease in individuals and in all populations. At the level of the kidney, natural physicochemical processes result in crystalluria and the formation and growth of stones. Urinary supersaturation of some degree must be present but its significance may be altered by changes in urinary volume, pH, epitaxial relationships, and the presence or absence of naturally occurring inhibitors. A variety of environmental parameters acting through effects on the local urinary conditions determine which patients among a group of people inherently at risk will form stones. The above factors are considered herein with regard to the four major types of stone disease encountered today.

Topics: Adult; Calcium Oxalate; Crystallization; Cystine; Female; Humans; Hydrogen-Ion Concentration; Kidney Calculi; Magnesium; Magnesium Compounds; Male; Phosphates; Risk; Sex Factors; Struvite; Uric Acid; Urinary Tract Infections

There are difficult problems in the management of urinary calculi associated with infections. Stones associated with infections are not only infection stones such as struvite stones, but also other kinds of stones such as calcium oxalate. Therefore, from practical view points, bacteriological studies should be carried out on urinary calculi associated with infections as a whole. We investigated 120 cases of urinary calculi associated with infections with special reference to bacteria on the stone surface, within the stone, compositions of the stone and permeation of an antibiotic into the stone. Proteus was isolated most frequently from the urine, followed by E. coli and Pseudomonas. These bacteria were isolated from the stone surface, although the incidence of Proteus mirabilis was higher than that in the urine. Bacteria were isolated in 25 of the 33 specimens of the inside parts and in 12 of the 12 stones of MAP and MAP plus other components. Proteus mirabilis was found in 7 of the 12 stones. Bacteria were isolated from the inside of 9 of the 16 stones of CaP and CaP plus other components and Proteus mirabilis was found in 6 of these 9 cases. Pseudomonas was isolated in 2 out of the 7 stones of CaP plus CaOX and its growth was seen in 5 specimens. The incorporation of an antibiotic, Cefmetazole, into the stone differed greatly with each stone. There were some cases in which the concentration of Cefmetazole in the inside was less than 5% of that in the outside. Stones may function as a sanctuary for organisms and may protect these organisms.

Topics: Adult; Aged; Anti-Bacterial Agents; Bacteria; Calcium Oxalate; Calcium Phosphates; Female; Humans; Magnesium; Magnesium Compounds; Male; Middle Aged; Phosphates; Struvite; Urinary Calculi; Urinary Tract Infections

The in vivo solubility of struvite stones experimentally induced in rats was investigated. The struvite stones implanted into bladders of normal rats were reduced in weight; and, they were dissolved by oral administration of ammonium chloride. Cefmetazone cured pyelonephritis and dissolved the bladder stones when it was administered to rats with urinary tract infection caused by Proteus mirabilis. Normalization of urine by antibiotics and acidifying agents may dissolve struvite stones, and help treat infection stones.

Topics: Ammonium Chloride; Animals; Cefmetazole; Cephamycins; Disease Models, Animal; In Vitro Techniques; Magnesium; Magnesium Compounds; Phosphates; Proteus Infections; Proteus mirabilis; Rats; Struvite; Urinary Bladder Calculi; Urinary Tract Infections

This report describes the results obtained with a combination of acetohydroxamic acid (AHA) and antibacterial agents in 13 patients with recurrent struvite stones complicated by refractory infections with urease-producing bacteria. Intravenous antibiotic pulses plus oral AHA achieved urine sterilisation in all. Then oral chemotherapy plus AHA was given for a mean period of 10.8 +/- 5.4 months. In four patients, the urine remained sterile, but in all the patients urinary pH remained below 6.4 and urinary NH4+ below 40 mg/dl. Despite the persistence of urea-splitting bacteria, the radiographic data showed an arrest of stone growth during the first year of treatment.

Topics: Anti-Bacterial Agents; Drug Therapy, Combination; Humans; Hydroxamic Acids; Magnesium; Magnesium Compounds; Phosphates; Struvite; Urease; Urinary Calculi; Urinary Tract Infections

Chronic urinary infection is thought to be a major factor in the causation of urinary calculi in paraplegic patients. Acetohydroxamic acid is reported to be effective in some patients for the management of this type of stone disease, but there have been no studies of urinary saturation levels during therapy with this drug. In this study 10 patients received oral acetohydroxamic acid for seven days. Marked lowering of urinary pH and ammonium levels were observed, but decreases in urinary saturation were small. The administration of acetohydroxamic acid resulted in increased urinary excretion of magnesium and phosphate, effects that have not previously been reported.

Topics: Adult; Calcium Phosphates; Humans; Hydrogen-Ion Concentration; Hydroxamic Acids; Magnesium; Magnesium Compounds; Male; Middle Aged; Paraplegia; Phosphates; Struvite; Urinary Calculi; Urinary Tract Infections

Brattleboro strain rats homozygous for hypothalamic diabetes insipidus (DI rat) excrete nearly their body weight per day in dilute urine and yet can form bladders stones composed of struvite and apatite. Studies were undertaken to investigate this apparent paradox. The results show that DI rat urine is indeed undersaturated with respect to struvite and apatite. However, chronic infection of DI rat urine with a urease-containing organism (Proteus mirabilis) results in the rapid formation of large struvite/apatite bladder stones. It is concluded that the Brattleboro strain DI rat, like man and unlike other rats, forms struvite/apatite calculi only in the presence at chronic urinary tract infection.

Topics: Animals; Apatites; Diabetes Insipidus; Hydrogen-Ion Concentration; Kidney Concentrating Ability; Magnesium; Magnesium Compounds; Osmolar Concentration; Phosphates; Proteus Infections; Rats; Rats, Brattleboro; Struvite; Urinary Bladder Calculi; Urinary Tract Infections

Topics: Animals; Disease Models, Animal; Disease Susceptibility; Dog Diseases; Dogs; Kidney Calculi; Magnesium; Magnesium Compounds; Phosphates; Proteus Infections; Proteus mirabilis; Quaternary Ammonium Compounds; Radiography; Staphylococcal Infections; Struvite; Urinary Bladder; Urinary Tract Infections

The composition of the stone was determined in 24 paraplegic patients from whom 26 stones were surgically removed. Twenty-five of the 26 stones consisted of 90 per cent magnesium ammonium phosphate and 10 per cent carbonate apatite. The remaining single stone was composed of 90 per cent calcium oxalate and 10 per cent magnesium ammonium phosphate. Renal function improved significantly with the removal of the stones.

Topics: Adult; Aged; Humans; Magnesium; Magnesium Compounds; Male; Middle Aged; Paraplegia; Phosphates; Spinal Cord Injuries; Struvite; Urinary Calculi; Urinary Tract Infections

We tested the inhibitory power and urinary excretion of several derivatives of hippurohydroxamic acid, including some newly synthesized compounds. m-Methoxyhippurohydroxamic acid (UCD II) strongly inhibited urease activity and high urinary excretion after oral administration to rats. UCD II inhibited the alkalinization of infected urine in vitro and in vivo and prevented bladder stone formation when it was orally administered to rats with urinary tract infection caused by Proteus mirabilis. The clinical application of UCD II to the prevention of pathologic sequelae of urinary infection with urease-producing bacteria awaits evaluation of the safety of the compound.

Topics: Animals; Hydroxamic Acids; Magnesium; Magnesium Compounds; Male; Phosphates; Proteus Infections; Proteus mirabilis; Quaternary Ammonium Compounds; Rats; Struvite; Urease; Urinary Bladder Calculi; Urinary Tract Infections

Magnesium ammonium phosphate calculi developed in the urinary bladders and urethras of four of five offspring of Miniature Schnauzer parents with recurrent struvite urolithiasis. Calculi were detected by radiograhy when the dogs were 12 to 15 months old. Males and females were affected. A significant number of urease-producing staphylococci were identified in the urine of three of four dogs before urolith formation, and in one dog after urolith formation. The dogs were evaluated until they were 26 months old. Serum concentrations of calcium, phosphorus, and magnesium were inside usual limits throughout the study. Abnormalities that might predispose to urinary tract infection were not identified by radiography or necropsy studies. In one dog, bladder calculi recurred after surgical removal of multiple cystoliths. In another, urethral obstruction and acute generalized pyelonephritis induced a lethal uremic crisis. Gross and microscopic lesions, detected after necropsy of all dogs with uroliths, were typical of bacterial infection.

Topics: Animals; Coagulase; Dog Diseases; Dogs; Female; Magnesium; Magnesium Compounds; Male; Phosphates; Quaternary Ammonium Compounds; Radiography; Staphylococcal Infections; Staphylococcus aureus; Struvite; Urease; Urinary Bladder Calculi; Urinary Calculi; Urinary Tract Infections

Urease positive staphylococcal urinary tract infection was experimentally induced in 13 dogs. Eight dogs developed cystic and/or urethral struvite calculi in 2 to 8 weeks. No abnormalities in systemic cell mediated immunity were detected in dogs before or after the establishment of the urinary tract infection. Miniature schnauzers whose ancestors had developed stones seemed to be no more susceptible to experimental urinary tract infection and stone formation than miniature schnauzers or beagles whose ancestors did not develop stones.

Topics: Animals; Dog Diseases; Dogs; Female; Kidney Calculi; Magnesium; Magnesium Compounds; Male; Phosphates; Quaternary Ammonium Compounds; Staphylococcal Infections; Struvite; Urethral Diseases; Urinary Bladder Calculi; Urinary Calculi; Urinary Tract Infections