LAUSR

Abstract Background Urinary tract infection (UTI) is one of the most common infectious diagnoses and in 2007 accounted for 10.5 million primary care visits in the US Advancing age and comorbidities, such as chronic kidney disease (CKD) and diabetes, affect antimicrobial prescribing habits. Sulfamethoxazole/trimethoprim (SMX-TMP), nitrofurantoin, and fosfomycin are first-line recommendations for uncomplicated cystitis. In an aging male population with potential allergies or contraindications to the above, fosfomycin is a potential option for treatment. Methods A retrospective chart review of fosfomycin prescribing habits at a large VA academic medical center. Patients were selected based on fosfomycin prescription in both inpatient and outpatient settings from January 1, 2004 to December 5, 2017. Data reviewed included indication, organism(s), susceptibility, duration of treatment, CKD, and clinical success. Treatment success was defined as no representation with UTI symptoms for 30 days. Results 117 cases of UTI in which fosfomycin was used were identified with a median patient age of 70 years old and 90% male. Twenty-five were uncomplicated cystitis, 49 complicated cystitis, and 34 catheter associated infections. Treatment success was obtained in 92% of the uncomplicated cystitis cases, 76% in complicated cystitis cases, and 67% in catheter associated UTIs. In half of all the cases an ESBL bacterium was isolated and 79% were successfully treated with fosfomycin. The most common pathogen identified was E. coli 58/118 (49%), followed by Klebsiella 25/118 (21%). Conclusion Fosfomycin is an antibiotic recommended for simple cystitis due to its safety profile, less collateral damage (gut flora disturbance), and low resistance as currently known. This review displays the largest ESBL cohort identified in the literature and uniquely used in a predominant male population. These findings suggest that ESBL producing bacteria can be treated successfully with fosfomycin in a male population as well as uncomplicated cystitis. However, caution should be used with catheterized patients as treatment was less effective regardless of isolated bacteria. Disclosures All authors: No reported disclosures.