sultamicillin and Gram-Positive-Bacterial-Infections

We report a case of empyema due to Gemella morbillorum. In this case, an analysis of the aspirate from the pleural effusion revealed empyema and evidence of a Gram-positive coccal bacteria. A biochemical identification system labelled the bacteria as 'unclassified', although we initially suspected the bacterium to belong to the Streptococcus species. 16S ribosomal RNA (16S rRNA) gene sequencing and a phylogenetic tree analysis of the isolated strain confirmed the presence of Gemella morbillorum. To ascertain the true incidence of Gemella species in empyema, 16S rRNA gene sequencing should be used when the standard conventional biochemical methods fail to identify the organism or it identifies it with a low degree of reliability.

Topics: Aged; Ampicillin; Anti-Bacterial Agents; Chest Tubes; Drainage; Dyspnea; Empyema; Fever; Gemella; Gram-Positive Bacterial Infections; Humans; Male; Microbial Sensitivity Tests; Phylogeny; Reproducibility of Results; RNA, Ribosomal, 16S; Sequence Analysis, RNA; Sulbactam; Treatment Outcome

Aspiration pneumonia (AP) and primary lung abscess (PLA), are diseases following aspiration of infectious material from the oropharynx or stomach. An antibiotic therapy, also covering anaerobic pathogens, is the treatment of choice. In this study we compared moxifloxacin (MXF) and ampicillin/sulbactam (AMP/SUL) concerning efficacy and safety in the treatment of AP and PLA.. Patients with pulmonary infections following aspiration were included in a prospective, open-label, randomized, multicenter trial. Sequential antibiotic therapy with MXF or AMP/SUL was administered until complete radiologic and clinical resolution.. A total of 139 patients with AP and PLA were included, 96 were evaluable for efficacy (EE, 48 patients in each treatment group). The overall clinical response rates in both groups were numerically identical (66.7%). MXF and AMP/SUL were both well tolerated, even after long-term administration [median duration of treatment (range) in days MXF versus AMP/SUL: AP 11 (4-45) vs 9 (3-25), PLA 30.5 (7-158) vs 35 (6-90)].. In the treatment of aspiration-associated pulmonary infections moxifloxacin appears to be clinically as effective and as safe as ampicillin/sulbactam; but, however, having the additional benefit of a more convenient (400 mg qd) treatment.

Topics: Adult; Ampicillin; Anti-Bacterial Agents; Aza Compounds; Female; Fluoroquinolones; Gram-Negative Bacterial Infections; Gram-Negative Facultatively Anaerobic Rods; Gram-Positive Bacterial Infections; Gram-Positive Cocci; Humans; Lung Abscess; Male; Moxifloxacin; Pneumonia, Aspiration; Quinolines; Radiography; Sulbactam

Cephalosporins are widely used and considered to be effective as prophylaxis in biliary surgery. Nevertheless, they lack activity against enterococci. We conducted a study to compare the efficacy of ampicillin-sulbactam vs cefuroxime in preventing surgical site infections following elective cholecystectomy.. A prospective randomized controlled trial.. A major tertiary care hospital.. Four hundred eighteen randomized patients (of 549 total), who from July 2002 to August 2004 underwent elective open or laparoscopic cholecystectomy with prospective assessment for development of surgical site infections for 1 month postoperatively.. A single intravenous dose of 1.5 g of cefuroxime (group A, n = 207) or 3 g of ampicillin-sulbactam (group B, n = 211) was administered during induction of anesthesia. Bile and gallbladder mucosal cultures were taken intraoperatively from all patients.. Number of postoperative surgical site infections.. A postoperative surgical site infection was noted in 19 (4.5%) of 418 patients, 18 from group A and 1 from group B (P<.001). In the group that received cefuroxime, 15 (83.3%) of 18 surgical site infections were due to Enterococcus species. Intraoperative bactibilia as well as intraoperative gallbladder rupture were associated with surgical site infections (P<.001).. A single dose of ampicillin-sulbactam favored better compared with cefuroxime for prevention of postoperative surgical site infections due to Enterococcus species after elective cholecystectomy. Ampicillin-sulbactam may be a better agent for antimicrobial prophylaxis in high-risk patients undergoing elective cholecystectomy, especially in a setting where the incidence of enterococcal infections is higher.

Topics: Ampicillin; Anti-Bacterial Agents; Cefuroxime; Chemoprevention; Cholecystectomy; Elective Surgical Procedures; Enterococcus; Female; Gram-Positive Bacterial Infections; Humans; Male; Middle Aged; Prospective Studies; Sulbactam; Surgical Wound Infection

Finegoldia magna (formerly called Peptostreptococcus magnus) is a Gram-positive anaerobic coccus which is increasingly recognized as an opportunistic pathogen. We present a case of F. magna associated non-valvular cardiovascular device-related infection in an 83 year-old male who received a permanent pacemaker for sick sinus syndrome seven weeks prior to his presentation. Five weeks after the implantation, the pacemaker and leads were explanted because of clinical evidence of pacemaker pocket infection. He was initially treated with sulfamethoxazole-trimethoprim based on the Gram stain results from the removed pacemaker. However, two weeks later, he was readmitted with sepsis and was successfully treated with ampicillin-sulbactam. Culture results from the pacemaker and pocket as well as blood cultures grew F. magna. Clinicians should be aware of the possibility of F. magna infection when initial gram stain results show "gram positive cocci".

Topics: Aged, 80 and over; Ampicillin; Animals; Anti-Bacterial Agents; Firmicutes; Gram-Positive Bacterial Infections; Humans; Male; Pacemaker, Artificial; Prosthesis-Related Infections; Sulbactam; Treatment Outcome; Trimethoprim, Sulfamethoxazole Drug Combination

Topics: Abducens Nerve Diseases; Actinomycosis; Ampicillin; Anti-Bacterial Agents; Child, Preschool; Coinfection; Diagnosis, Differential; Fatigue; Fusobacterium Infections; Fusobacterium nucleatum; Gram-Positive Bacterial Infections; Humans; Male; Mastoiditis; Otitis Media; Peptostreptococcus; Pneumonia, Bacterial; Recurrence; Sulbactam; Syndrome; Trigeminal Neuralgia; Weight Loss

An 87-year-old man with poorly controlled diabetic mellitus presented with fever, bedsores, and elevated hepatobiliary enzyme levels. He was diagnosed with bacteremia with acute cholangitis due to Arthrobacter species, which are Gram-positive, aerobic, catalase-positive, coryneform bacteria belonging to the family Microbacteriaceae. Doripenem and subsequencial sulbactam/ampicillin treatment were used for the acute cholangitis, and the bacteremia was treated with a 2-week course of vancomycin. The bacteremia was misidentified by the phenotyping assay (API Coryne test), but was identified as Arthrobacter creatinolyticus by 16S rRNA and matrix-assisted laser-desorption/ionization time-of-flight mass spectrometry. To our knowledge, this is the first report of a human case of A. creatinolyticus bacteremia.

Topics: Aerobiosis; Aged, 80 and over; Ampicillin; Anti-Bacterial Agents; Arthrobacter; Bacteremia; beta-Lactamase Inhibitors; Carbapenems; Cholangitis; Diabetes Complications; DNA, Bacterial; DNA, Ribosomal; Doripenem; Gram-Positive Bacterial Infections; Humans; Male; RNA, Ribosomal, 16S; Sequence Analysis, DNA; Sulbactam

Parvimonas micra is a fastidious, anaerobic, gram positive coccus, which is found in normal human oral and gastrointestinal flora. It has also been known as Peptostreptococcus micros and Micromonas micros with its most recent re-classification in 2006. It has been described in association with hematogenous seeding of prosthetic joints [1,2]. Several cases of discitis and osteomyelitis have been described in association with dental procedures and periodontal disease often with a subacute presentation. However, cases of native joint septic arthritis are limited [3-5]. Per our literature review, there is one case of native knee septic arthritis described in 1999, with a prolonged time to diagnosis and treatment due to difficulty culturing P. micra. The previously reported patient experienced significant joint destruction and morbidity [6]. Advances in culture techniques and new methods of organism identification including MALDI-TOF and 16s rRNA sequencing have lead to increased identification of this organism, which may be a more frequent bone and joint pathogen than previously realized.

Topics: Aged; Ampicillin; Anaerobiosis; Anti-Bacterial Agents; Arthritis, Infectious; Bacterial Typing Techniques; Clindamycin; Gram-Positive Bacterial Infections; Humans; Knee Joint; Male; Peptostreptococcus; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; Sulbactam

In liver transplant (LT) recipients, surgical site infection (SSI) represents an important cause of morbidity and mortality.. This study measures the impact of a multimodal approach to the incidence of surgical site infection in LT recipients.. All of the LT recipients in our department were registered on the national database in solid organ transplant. A study was performed in two analytical-interventional phases. Phase 1 took place between July 14, 2009, and February 20, 2014. Phase 2 took place between February 21, 2014, and July 15, 2015. The multimodal change implemented during phase 1 was that 0.5% alcoholic chlorhexidine and ether were applied to the surgical field; surgical prophylaxis was primarily with ampicillin/sulbactam plus cefazolin. In phase 2, 2% alcoholic chlorhexidine alone was applied to the surgical field. The prior standard prophylaxis was changed to piperacillin tazobactam administered during surgery as a continuous infusion of 13.5 g over 8 hours with a pre-incision loading dose of 4.5 g. The loading dose of piperacillin tazobactam was combined with a single dose of gentamicin of 5 mg/kg.. One hundred eight patients have received transplants since the start of the program: 82 patients during phase one and 26 patients during phase two. During phase 1, 13 cases of SSI were recorded, representing a rate of 15.85 per 100 transplants. Sixteen micro-organisms were isolated during phase 1, of which 12 corresponded to gram-negative bacilli. With regard to resistance profiles, 13 showed multidrug resistant and extensively drug resistant profiles. During phase 2, no cases of SSI were recorded (relative risk = 0.158 [95% confidence interval 0.0873-0.255], P = .0352].. A multimodal approach allowed for the reduction of the incidence of SSI in LTs and offered a protective strategy.

Topics: Administration, Cutaneous; Adult; Ampicillin; Anti-Bacterial Agents; Anti-Infective Agents, Local; Antibiotic Prophylaxis; Cefazolin; Chlorhexidine; Drug Administration Schedule; Drug Therapy, Combination; Ether; Female; Gentamicins; Gram-Negative Bacterial Infections; Gram-Positive Bacterial Infections; Humans; Infusions, Intravenous; Liver Transplantation; Male; Middle Aged; Penicillanic Acid; Piperacillin; Piperacillin, Tazobactam Drug Combination; Sulbactam; Surgical Wound Infection; Transplant Recipients

We report on the first case of a periprosthetic joint infection with the anaerobic spore-forming Gram-positive rod Robinsoniella peoriensis as the causative agent. The bacterium was first isolated from a swine manure storage pit and has so far rarely been associated with human infections.

Topics: Aged; Ampicillin; Animals; Anti-Bacterial Agents; Arthroplasty, Replacement, Hip; Female; Firmicutes; Gram-Positive Bacteria; Gram-Positive Bacterial Infections; Humans; Joint Prosthesis; Manure; Prosthesis-Related Infections; Spores, Bacterial; Sulbactam; Swine

Negligible in vivo growth of enterococci and high-level dispersion of data have led to inaccurate estimations of antibiotic pharmacodynamics (PD). Here we improved an in vivo model apt for PD studies by optimizing the in vitro culture conditions for enterococci. The PD of vancomycin (VAN), ampicillin-sulbactam (SAM), and piperacillin-tazobactam (TZP) against enterococci were determined in vivo, comparing the following different conditions of inoculum preparation: aerobiosis, aerobiosis plus mucin, and anaerobiosis plus mucin. Drug exposure was expressed as the ratio of the area under the concentration-time curve for the free, unbound fraction of the drug to the MIC (fAUC/MIC) (VAN) or the time in a 24-h period that the drug concentration for the free, unbound fraction exceeded the MIC under steady-state pharmacokinetic conditions (fT(>MIC)) (SAM and TZP) and linked to the change in log10 CFU/thigh. Only anaerobiosis plus mucin enhanced the in vivo growth, yielding significant PD parameters with all antibiotics. In conclusion, robust in vivo growth of enterococci was crucial for better determining the PD of tested antibacterial agents, and this was achieved by optimizing the procedure for preparing the inoculum.

Topics: Ampicillin; Anaerobiosis; Animals; Anti-Bacterial Agents; Disease Models, Animal; Enterococcus faecalis; Female; Gram-Positive Bacterial Infections; Mice, Inbred ICR; Microbial Sensitivity Tests; Mucins; Penicillanic Acid; Piperacillin; Piperacillin, Tazobactam Drug Combination; Sulbactam; Vancomycin

A newly acquired rhesus macaque was suffering from rapid destruction of the left cheek caused by necrotizing stomatitis.. To restore reconstructive surgery and intensive care with antibiotics, wound protection, wound healing agents, and debridement were applied.. Staphylococcus aureus and Enterococcus faecalis were isolated from the culture of the lesion, and the antibiotic susceptibility test revealed methicillin-resistant Staphylococcus aureus infection. Vancomycin and ampicillin-sulbactam effectively treated the bacterial infections, and reconstructive surgery was performed once the infection was cleared. Topical application of recombinant human epidermal growth factor (rhEGF) was useful to treat exposed wound of the noma lesion.. Simian noma associated with methicillin-resistant Staphylococcus aureus (MRSA) had not previously been reported in non-human primates. Although noma associated with MRSA is hard to cure because of its rapid and destructive progress, the aggressive therapy used in this study led to the successful resolution of an acute necrotic stomatitis lesion in a rhesus macaque.

Topics: Ampicillin; Animals; Anti-Bacterial Agents; Enterococcus faecalis; Epidermal Growth Factor; Gram-Positive Bacterial Infections; Humans; Macaca mulatta; Male; Methicillin-Resistant Staphylococcus aureus; Monkey Diseases; Mouth; Necrosis; Noma; Oral Surgical Procedures; Plastic Surgery Procedures; Staphylococcal Infections; Stomatitis; Sulbactam; Vancomycin; Wound Healing

Although polymicrobial infections, such as peri-implantitis or periodontitis, were postulated in the literature to be caused by synergistic effects of bacteria, these effects remain unclear looking at antibiotic susceptibility. The aim of this study is to compare the antibiotic susceptibilities of pure cultures and definite cocultures.. Laboratory strains of Aggregatibacter actinomycetemcomitans (Aa) (previously Actinobacillus actinomycetemcomitans), Capnocytophaga ochracea (Co), and Parvimonas micra (Pm) (previously Peptostreptococcus micros) were cultivated under anaerobic conditions, and their susceptibilities to 10 antibiotics (benzylpenicillin G, ampicillin, amoxicillin, ampicillin/sulbactam, amoxicillin/clavulanic acid, minocycline, metronidazole, linezolid, azithromycin, and moxifloxacin) were tested using the Epsilometertest. Cocultures, each consisting of two or three bacteria, were treated analogously.. All four cocultures showed lower susceptibilities to azithromycin and minocycline than to pure cultures. The coculture Aa-Co showed a lower susceptibility to moxifloxacin as did the coculture Aa-Pm to benzylpenicillin G; the coculture Co-Pm showed a lower susceptibility to amoxicillin, amoxicillin/clavulanic acid, metronidazole, and benzylpenicillin G. However, the coculture Co-Pm showed a higher susceptibility to ampicillin, linezolid and moxifloxacin as did Aa-Pm and Aa-Co-Pm to linezolid.. In addition to established in vitro assays, it was demonstrated that antimicrobial cocultures caused antibiotic susceptibilities that differed from those of pure cultures. Bacterial cocultures frequently showed lowered susceptibilities to antibiotics.

Topics: Acetamides; Actinobacillus Infections; Aggregatibacter actinomycetemcomitans; Amoxicillin; Amoxicillin-Potassium Clavulanate Combination; Ampicillin; Anti-Bacterial Agents; Anti-Infective Agents; Aza Compounds; Azithromycin; Capnocytophaga; Coculture Techniques; Coinfection; Drug Resistance, Bacterial; Fluoroquinolones; Gram-Negative Bacterial Infections; Gram-Positive Bacterial Infections; Humans; Linezolid; Metronidazole; Microbial Interactions; Minocycline; Moxifloxacin; Oxazolidinones; Penicillin G; Peptostreptococcus; Peri-Implantitis; Periodontitis; Quinolines; Sulbactam

Topics: Ampicillin; Anti-Bacterial Agents; Drug Resistance, Bacterial; Enterococcus faecalis; Gram-Positive Bacterial Infections; Hematopoietic Stem Cell Transplantation; Humans; Infant; Male; Sulbactam; Vancomycin

The fixed antibacterial combination of ampicillin and sulbactam is frequently used for various infections. The normal kidneys eliminate approximately 60% of ampicillin (371.39 Da) and sulbactam (255.22 Da). Concomitant with the decline in renal function, the terminal elimination half-life increases from 1 up to 24 h in patients with ESRD. Patients on three times weekly low flux haemodialysis exhibit a half-life of 2.3 h on and 17.4 h off dialysis. In contrast, in the present observation the elimination half-life in a single patient with acute kidney injury undergoing extended daily dialysis (EDD) with a polysulphone membrane was 1.5 h, indicating that the current dosing regimen for haemodialysis outpatients (ampicillin/sulbactam 2.0/1.0 g/day) would result in a significant underdosing for patients undergoing EDD.

Topics: Acute Kidney Injury; Aged; Ampicillin; Anti-Bacterial Agents; Enterococcus faecalis; Gram-Positive Bacterial Infections; Humans; Male; Renal Dialysis; Risk Factors; Sulbactam; Urinary Tract Infections

The genus Ruminococcus which are anaerobe Gram positive cocci, previously classified as Peptostreptococcus, may colonize the upper respiratory tract, gastrointestinal tract, vagina and skin of humans and animals. In this report a case of liver abscess and a case of infective endocarditis caused by Ruminoccocus productus, which is very rarely encountered in the clinical practice were presented. The first case was a 32 years old male who was admitted to the hospital in 2002, with the complaints of fever lasting for 20 days and pain while breathing. The abdominal ultrasonography revealed the presence of a liver abscess, and the drainage material from the abscess yielded Ruminococcus productus, identified in BACTEC 9200 (Becton Dickinson, Sparks, Md) anaerobe system. As the isolate was found to be sensitive to penicilin, the empirical gentamicin and ampicillin/sulbactam therapy was continued. The second case was a 25 years old male who was admitted to the hospital in 2005, with the signs of fever lasting for 3-4 months, chills, bone and joint pains. As multiple vegetations were detected in echocardiography, blood cultures were collected and empirical therapy with ceftriaxone and gentamicin was initiated with the preliminary diagnosis of infective endocarditis. Bacteria which were isolated from blood cultures by BACTEC 9200 system have been identified as R. productus. As this strain was also sensitive to penicillin, the empirical therapy was changed to penicilin and gentamicin. These two cases indicated that R. productus should be considered in complicated infections even if it is a rarely isolated species from the clinical samples.

Topics: Adult; Ampicillin; Anti-Bacterial Agents; Drug Therapy, Combination; Endocarditis, Bacterial; Gentamicins; Gram-Positive Bacterial Infections; Humans; Liver Abscess; Male; Penicillins; Ruminococcus; Sulbactam

Enterococcal meningitis is an uncommon disease usually caused by Enterococcus faecalis and Enterococcus faecium and is associated with a high mortality rate. Enterococcus casseliflavus has been implicated in a wide variety of infections in humans, but never in meningitis.. A 77-year-old Italian female presented for evaluation of fever, stupor, diarrhea and vomiting of 3 days duration. There was no history of head injury nor of previous surgical procedures. She had been suffering from rheumatoid arthritis for 30 years, for which she was being treated with steroids and methotrexate. On admission, she was febrile, alert but not oriented to time and place. Her neck was stiff, and she had a positive Kernig's sign. The patient's cerebrospinal fluid was opalescent with a glucose concentration of 14 mg/dl, a protein level of 472 mg/dl, and a white cell count of 200/muL with 95% polymorphonuclear leukocytes and 5% lymphocytes. Gram staining of CSF revealed no organisms, culture yielded E. casseliflavus. The patient was successfully treated with meropenem and ampicillin-sulbactam.. E. casseliflavus can be inserted among the etiologic agents of meningitis. Awareness of infection of central nervous system with Enterococcus species that possess an intrinsic vancomycin resistance should be increased.

Topics: Aged; Ampicillin; Anti-Bacterial Agents; Cerebrospinal Fluid; Enterococcus; Female; Gram-Positive Bacterial Infections; Humans; Meningitis, Bacterial; Meropenem; Microbial Sensitivity Tests; Sigmoid Diseases; Sulbactam; Thienamycins

The present study was designed to investigate the effects of prophylactic antibiotic therapy and the cost-effectiveness of Cefazolin (CEZ) and Sulbactam/Ampicillin (SBT/ABPC) in gastric cancer surgery employing clinical pathway. 157 patients (62 in the CEZ group and 95 in the SBT/ABPC group), who underwent surgery for gastric cancer at the First Department of Surgery of our hospital, were investigated. There was no significant difference between the groups with regard to sex, age, incidence of complication, stage of cancer, surgical method, operative time and blood loss, length of hospitalization, the appearance of systemic inflammatory response syndrome (SIRS), changes body temperature, white blood cell count (WBC), C-reactive protein (CRP), or clinical outcome of postoperative care by a nurse during post-operation for 7 days. The prophylactic effect of infection was also no different between the CEZ (69.4%) and SBT/ABPC (69.5%) groups. In contrast, decision analysis strongly indicated that the anticipate cost of antibiotics was higher in the latter group (yen 20402) than in the CEZ group (yen 15556), suggesting that the prophylactic effect of CEZ may be more cost-effective. Thus, evaluations of pharmacotherapy from the aspect of cost may be one of the important responsibility of hospital pharmacists in the future.

Topics: Aged; Ampicillin; Antibiotic Prophylaxis; Cefazolin; Cost-Benefit Analysis; Critical Pathways; Female; Gastrectomy; Gram-Positive Bacterial Infections; Humans; Male; Middle Aged; Postoperative Complications; Retrospective Studies; Stomach Neoplasms; Sulbactam

Topics: Adult; Ampicillin; Bacillus; Bacteremia; Blood; Drug Therapy, Combination; Female; Gentamicins; Gram-Positive Bacterial Infections; Humans; Pregnancy; Sulbactam

Antibiotic-resistant enterococci are being increasingly identified as causal agents of infection. Trovafloxacin is a new fluoronaphthyridone with enhanced activity against gram-positive cocci and variable activity reported against Enterococcus spp. Twenty-one strains of vancomycin-resistant Enterococcus faecium and two strains of Enterococcus faecalis (one vancomycin resistant) were studied at an initial inoculum of 10(6) CFU/ml in time-kill assays with trovafloxacin (3 mg/liter), ampicillin-sulbactam (100/50 mg/liter), and the combination. Six strains of E. faecium (five vancomycin resistant) also were studied in an in vitro two-compartment dynamic model that mimics human pharmacokinetics with trovafloxacin simulated at 300 mg every 12 h (q12h), ampicillin-sulbactam at 2/1 g q6h, and the combination. Peripheral compartments were sampled q2h for 30 h for bacterial counts. Trovafloxacin MICs ranged from 0.5 to 32 mg/liter, and the nine strains of vancomycin-resistant E. faecium for which MICs were < or =2 mg/liter were more likely to show a reduction of 2 log units or more in viable counts in time-kill assays than were strains for which MICs were higher. Synergism with ampicillin-sulbactam was found for only one strain (trovafloxacin MIC, 16 mg/liter). Similar results were obtained in the pharmacokinetic model, with 2- to 4-log-unit reductions in viable bacteria for trovafloxacin-susceptible strains. Although no convincing evidence of synergism was found, ampicillin-sulbactam in combination minimized late bacterial regrowth of two trovafloxacin-susceptible strains. These data suggest that this high dose of trovafloxacin (with or without ampicillin-sulbactam) might be useful against strains of vancomycin-resistant E. faecium for which MICs were < or =2 mg/liter.

Topics: Ampicillin; Anti-Infective Agents; Drug Resistance, Microbial; Drug Synergism; Drug Therapy, Combination; Enterococcus faecalis; Enterococcus faecium; Fluoroquinolones; Gram-Positive Bacterial Infections; Microbial Sensitivity Tests; Naphthyridines; Sulbactam

Increasing antibiotic resistance in the enterococci, including the capacity for beta-lactamase production and the development of high-level aminoglycoside resistance, has complicated the treatment of serious enterococcal infections, which often require synergistic antibiotic combinations for cure. We utilized the rabbit model of aortic valve endocarditis to investigate the effects of various antibiotics, alone and in combination, against a multiply antibiotic-resistant isolate of Enterococcus faecalis. Female New Zealand White rabbits were infected with either a beta-lactamase-producing, gentamicin-resistant isolate of E. faecalis or a non-beta-lactamase-producing, aminoglycoside-susceptible isolate, and the mean log10 CFU per gram of vegetation were determined. The most active agents were low-dose ampicillin-sulbactam (200 mg/kg of body weight per day), high-dose ampicillin-sulbactam (400 mg/kg of body weight per day), and vancomycin (150 mg/kg of body weight per day), which reduced the titers of bacteria by 2.27, 2.76, and 2.85 log10 (CFU/g, respectively, compared with controls. While ampicillin-sulbactam and vancomycin were equally efficacious in reducing titers of bacteria in vegetations, no animals were cured (defined as < 2 log10 CFU/g of vegetation) by either agent, whether treatment was continued for 3 or 7 days. The addition of gentamicin was not associated with increased killing in rabbits infected with the aminoglycoside-resistant isolate. Both high-dose ampicillin-sulbactam and vancomycin regimens demonstrated significant, continued reduction in bacterial titers with the longer periods of treatment (P < or = 0.05); 7-day treatment with high-dose ampicillin-sulbactam produced a greater reduction in bacterial titers in vegetation than 7-day treatment with vancomycin (P < or = 0.05). We conclude that ampicillin-sulbactam and vancomycin are equally effective in the treatment of experimental endocarditis due to beta-lactamase-producing, highly gentamicin-resistant E. faecalis. The optimum therapy for such infections in humans is not known.

Topics: Ampicillin; Animals; Aortic Valve; beta-Lactamases; Disease Models, Animal; Drug Resistance, Microbial; Drug Therapy, Combination; Endocarditis, Bacterial; Enterococcus faecalis; Female; Gentamicins; Gram-Positive Bacterial Infections; Rabbits; Sulbactam; Vancomycin

Topics: Ampicillin; Animals; beta-Lactamases; Drug Therapy, Combination; Endocarditis, Bacterial; Enterococcus faecalis; Gram-Positive Bacterial Infections; Humans; Rabbits; Species Specificity; Sulbactam