warfarin and Urinary-Tract-Infections

Hip fracture patients in general are elderly and they often have comorbidities that may necessitate anticoagulation treatment, such as warfarin. It has been emphasized that these patients benefit from surgery without delay to avoid complications and reduce mortality. This creates a challenge for patients on warfarin and especially for those with trochanteric or subtrochanteric hip fractures treated with intramedullary nailing, as this is associated with increased bleeding compared to other types of hip fractures and surgical methods. The aim of the study was to evaluate if early surgery (within 24 h) of trochanteric or subtrochanteric hip fractures using intramedullary nailing is safe in patients on warfarin treatment after fast reversal of the warfarin effect.. A retrospective case-control study including 198 patients: 99 warfarin patients and 99 patients without anticoagulants as a 1:1 ratio control group matched for age, gender and surgical implant. All patients were operated within 24 h with a cephalomedullary nail due to a trochanteric or subtrochanteric hip fracture. All patients on warfarin were reversed if necessary to INR ≤ 1.5 before surgery using vitamin K and/or four-factor prothrombin complex concentrate (PCC). Per- and postoperative data, transfusion rates, adverse events and mortality was compared.. There were no significant differences in the calculated blood-loss, in-house adverse events or mortality (in-house, 30-day or 1-year) between the groups. There were no significant differences in the pre- or peroperative transfusions rates, but there was an increased rate of postoperative transfusions in the control group (p = 0.02).. We found that surgical treatment with intramedullary nailing within 24 h of patients with trochanteric or subtrochanteric hip fractures on warfarin medication after reversing its effect to INR ≤ 1.5 using vitamin K and/or PCC is safe.

Topics: Aged; Aged, 80 and over; Anticoagulants; Bone Nails; Case-Control Studies; Female; Hip Fractures; Humans; Male; Patient Safety; Retrospective Studies; Time Factors; Time-to-Treatment; Urinary Tract Infections; Warfarin

The cephalosporin class has been associated with an increased risk of bleeding among elderly patients receiving warfarin. Urinary tract infections (UTI) are the most prevalent infection in elderly patients.. To determine the extent of interaction between antibiotics used in the treatment of UTI, particularly specific cephalosporins and warfarin.. A retrospective chart review was conducted on chronic warfarin patients with a diagnosis of UTI treated with ceftriaxone, a first-generation cephalosporin, penicillin, or ciprofloxacin. The primary outcome was the comparison of the extent of international normalized ratio (INR) change from baseline between each antibiotic group.. The ceftriaxone group was found to have a statistically significant higher peak INR value compared to all other studied antibiotics (ceftriaxone: 3.56, first-generation cephalosporins: 2.66, penicillins: 2.98, ciprofloxacin: 2.3; P = .004), a statistically significant greater extent of change in INR value (+1.19, +0.66, +0.8, +0.275; P = .006), and a statistically significant greater percentage change in INR value when compared to ciprofloxacin (54.4% vs 12.7%; P = .037).. Ceftriaxone interacts with warfarin to increase a patient's INR value more than other commonly administered antibiotics for UTI treatment. Other antibiotics should be preferred for UTI treatment in patients on warfarin.

Topics: Aged; Anti-Bacterial Agents; Ceftriaxone; Cephalosporins; Ciprofloxacin; Drug Synergism; Drug Therapy, Combination; Humans; International Normalized Ratio; Penicillins; Retrospective Studies; Urinary Tract Infections; Warfarin

Topics: Fatal Outcome; Female; Heart Failure, Systolic; Humans; Male; Middle Aged; Myocardial Infarction; Pancreatic Neoplasms; Physician-Patient Relations; Urinary Tract Infections; Venous Thrombosis; Warfarin

Topics: Acute Kidney Injury; Adult; Anti-Bacterial Agents; Anticoagulants; Blood Coagulation Disorders; Cardiomyopathy, Dilated; Drug Interactions; Hematuria; Humans; International Normalized Ratio; Levofloxacin; Male; Ofloxacin; Shock; Urinary Tract Infections; Warfarin

The case of a patient receiving long-term warfarin therapy who experienced elevated International Normalized Ratio (INR) values on two occasions after injections of ceftriaxone is reported.. An elderly woman (age, 67 years) with multiple comorbidities who had been receiving warfarin therapy for about 8 years was given an intramuscular injection of ceftriaxone 1 g for the treatment of a urinary tract infection. Four days later, her INR (which had recently ranged from 1.9 to 3.0 at a weekly warfarin dosage of 52.5-54.5 mg) was 10.74. One scheduled warfarin dose was withheld and 5 mg of phytonadione administered; one day later, the INR was 3.4 (goal, 2.5-3.5). INR values remained stable for several weeks until the patient again received a 1-g ceftriaxone injection for an infection (she was also prescribed oral cefuroxime and phenazopyridine); four days later, the INR was 16.99. Again, the scheduled warfarin dose was withheld and 5 mg of phytonadione administered. One day later, the INR had declined to 4.6 but remained above the target range; therefore, warfarin was withheld for a second day, after which the patient received 7.5 mg of warfarin sodium daily for two days, resulting in an INR decrease to 2.1. The patient continued to receive 7.5 mg of warfarin sodium daily, and at one-week follow-up the INR value (2.5) was within the therapeutic range.. A 67-year-old American Indian woman with previously stable INR values during long-term warfarin therapy after mitral valve replacement surgery had INR elevations on two occasions after receiving ceftriaxone for urinary tract infections.

Topics: Aged; Anti-Bacterial Agents; Anticoagulants; Antifibrinolytic Agents; Ceftriaxone; Drug Interactions; Female; Follow-Up Studies; Humans; Injections, Intramuscular; International Normalized Ratio; Urinary Tract Infections; Vitamin K 1; Warfarin

Some antibiotic agents, including cotrimoxazole, inhibit the metabolism of warfarin sodium and possibly increase the risk of hemorrhage. We examined the risk of upper gastrointestinal (UGI) tract hemorrhage in older patients receiving warfarin in combination with antibiotics commonly used to treat urinary tract infection, with a focus on cotrimoxazole.. This population-based, nested case-control study using health care databases in Ontario, Canada, between April 1, 1997, and March 31, 2007, identified residents 66 years or older who were continuously treated with warfarin. Cases were hospitalized with UGI tract hemorrhage. For each case, we selected up to 10 age- and sex-matched control subjects. We calculated adjusted odds ratios (aORs) for exposure to cotrimoxazole, amoxicillin trihydrate, ampicillin trihydrate, ciprofloxacin hydrochloride, nitrofurantoin, and norfloxacin within 14 days before the UGI tract hemorrhage.. We identified 134 637 patients receiving warfarin, of whom 2151 cases were hospitalized for UGI tract hemorrhage. Cases were almost 4 times more likely than controls to have recently received cotrimoxazole (aOR, 3.84; 95% confidence interval [CI], 2.33-6.33). Treatment with ciprofloxacin was also associated with increased risk (aOR, 1.94; 95% CI, 1.28-2.95), but no significant association was observed with amoxicillin or ampicillin (1.37; 0.92-2.05), nitrofurantoin (1.40; 0.71-2.75), or norfloxacin (0.38; 0.12-1.26). Compared with amoxicillin or ampicillin, cotrimoxazole prescription was associated with an almost 3-fold risk (ratio of ORs, 2.80; 95% CI, 1.48-5.32).. Among older patients receiving warfarin, cotrimoxazole is associated with a significantly higher risk of UGI tract hemorrhage than other commonly used antibiotics. Whenever possible, clinicians should prescribe alternative antibiotics in patients receiving warfarin.

Topics: Aged; Aged, 80 and over; Amoxicillin; Ampicillin; Anti-Infective Agents, Urinary; Anticoagulants; Case-Control Studies; Databases, Factual; Drug Interactions; Drug Therapy, Combination; Female; Gastrointestinal Hemorrhage; Humans; Male; Multivariate Analysis; Odds Ratio; Ontario; Trimethoprim, Sulfamethoxazole Drug Combination; Urinary Tract Infections; Warfarin

An 80-year old woman presented with macroscopic hematuria on June 4(th), 2008. She had been suffering from general malaise and appetite loss since about 10 days previously. She had received anticoagulant therapy with warfarin due to chronic atrial fibrillation and PT-INR was well controlled between 1.6-2.2. When she presented, PT-INR was 12.88, and urinary tract infection (UTI) and hypoalbuminemia (2.2 g/dl) were observed. Therefore, warfarin therapy was discontinued, and antibiotics and vitamin K were administered. Normalization of PT-INR resulted in the disappearance of hematuria and UTI improved as a result of antibiotics administration. As the appetite loss improved, for serum albumin level increased. The previous dose of warfarin achieved PT-INR around 1.8. Her drug compliance had been good, and she took no drug nor food which could interact with warfarin. We also found no liver dysfunction, acute renal failure, malignancy, nor hyper- or hypo-thyroidism. Hypoalbuminemia caused by appetite loss due to UTI seems very likely to increase concentration of circulating free warfarin resulting in extreme prolongation of PT-INR. Our findings in the present case may suggest that we should pay more attention on changes of drug pharmacokinetics in elderly patients because of their poor adaptation to their circumstances such as infection or dehydration.

Topics: Aged, 80 and over; Anorexia; Atrial Fibrillation; Chronic Disease; Female; Humans; Prothrombin Time; Urinary Tract Infections; Warfarin

(1) Female urinary tract infections are common and often recurrent. Food supplements based on cranberries are said to prevent recurrent urinary tract infections. (2) Two randomised controlled trials involving a total of about 300 young women showed that daily use of cranberry juice or tablets reduced the relapse rate for acute cystitis: on average, treating 100 women for one year prevented at least 1 urinary tract infection in 15 to 33 women. The daily doses were 7.5 g of concentrate in 50 ml of water, 750 ml of juice, or two tablets of concentrate. (3) In elderly patients, 2 trials of cranberry-based products in hospitals or nursing homes showed a small reduction in the frequency of relapses. (4) Adverse effects appear to be negligible. However, several case reports of interactions with warfarin have been published, including one involving severe bleeding. Patients on vitamin K antagonists must be warned about this risk of interactions so that they avoid consuming cranberry-based products without medical supervision.

Topics: Bacteriuria; Double-Blind Method; Female; Food-Drug Interactions; Fruit; Humans; Phytotherapy; Plant Preparations; Randomized Controlled Trials as Topic; Self Care; Urinary Tract Infections; Vaccinium macrocarpon; Warfarin

Topics: Anticoagulants; Food-Drug Interactions; Humans; International Normalized Ratio; Phytotherapy; Urinary Tract Infections; Vaccinium macrocarpon; Warfarin

Topics: Aged; Anti-Infective Agents, Urinary; Anticoagulants; Brain Ischemia; Drug Interactions; Drug Synergism; Hospitalization; Humans; Male; Nursing Assessment; Trimethoprim, Sulfamethoxazole Drug Combination; Urinary Tract Infections; Warfarin

A 76-year-old woman receiving warfarin after aortic valve replacement experienced prosthetic valve thrombosis during dicloxacillin therapy. Successful thrombolysis was achieved with tissue plasminogen activator. The international normalized ratio (INR) on admission was reduced to 1.4 and an increased warfarin dosage was required for three weeks following discontinuation of dicloxacillin treatment in order to maintain therapeutic INRs. Careful monitoring of INRs and titration of the warfarin dosage is recommended when dicloxacillin is prescribed to patients receiving warfarin.

Topics: Aged; Anticoagulants; Aortic Valve; Cineradiography; Dicloxacillin; Drug Therapy, Combination; Echocardiography, Doppler; Female; Heart Valve Diseases; Heart Valve Prosthesis; Heparin; Humans; Penicillins; Plasminogen Activators; Thrombolytic Therapy; Thrombosis; Tissue Plasminogen Activator; Urinary Tract Infections; Warfarin

Topics: Aged; Atrial Fibrillation; Drug Interactions; Female; Hematoma; Humans; Pharyngeal Diseases; Pharynx; Radiography; Sulfamethoxazole; Trimethoprim; Urinary Tract Infections; Warfarin; Whole Blood Coagulation Time

The prothrombin time (PT) of a patient undergoing warfarin sodium anticoagulation became elevated when sulfisoxazole was given concurrently. The warfarin dose index is used to demonstrate that this PT prolongation was the result of a warfarin-sulfisoxazole interaction. The mechanism of this interaction may involve displacement of warfarin from serum albumin. Sulfisoxazole should be used cautiously, if at all, in patients taking warfarin.

Topics: Aged; Blood Coagulation; Drug Synergism; Female; Humans; Pulmonary Embolism; Sulfisoxazole; Urinary Tract Infections; Warfarin

Topics: Drug Interactions; Drug Synergism; Escherichia coli Infections; Female; Humans; Middle Aged; Nalidixic Acid; Prothrombin Time; Purpura; Thrombophlebitis; Urinary Tract Infections; Warfarin

Topics: Adult; Age Factors; Cholecystitis; Chromium Alloys; Follow-Up Studies; Gastrointestinal Hemorrhage; Hepatitis; Hip; Hip Dislocation; Hip Joint; Humans; Joint Prosthesis; Middle Aged; Molecular Weight; Peripheral Nervous System Diseases; Polyethylenes; Postoperative Complications; Prosthesis Design; Surgical Wound Infection; Thromboembolism; Urinary Tract Infections; Warfarin