Assessment of Fosfomycin for Complicated or Multidrug-Resistant Urinary Tract Infections: Patient Characteristics and Outcomes

Abstract

Background: Bacterial resistance among uropathogens is on the rise and has led to a decreased effectiveness of oral therapies. Fosfomycin tromethamine (fosfomycin) is indicated for uncomplicated urinary tract infections (UTIs) and displays in vitro activity against multidrug-resistant (MDR) isolates; however, clinical data assessing fosfomycin for the treatment of complicated or MDR UTIs are limited. Methods: We conducted a retrospective evaluation of patients who received ≥1 dose of fosfomycin between January 2009 and September 2015 for treatment of a UTI. Patients were included if they had a positive urine culture and documented signs/symptoms of a UTI. Results: Fifty-seven patients were included; 44 (77.2%) had complicated UTIs, 36 (63.2%) had MDR UTIs, and a total of 23 (40.4%) patients had a UTI that was both complicated and MDR. The majority of patients were female (66.7%) and elderly (median age, 79 years). Overall, the most common pathogens isolated were Escherichia coli (n = 28), Enterococcus spp. (n = 22), and Pseudomonas aeruginosa (n = 8). Twenty-eight patients (49.1%) were clinically evaluable; the preponderance achieved clinical success (96.4%). Fifteen out of 20 (75%) patients with repeat urine cultures had a microbiological cure. Conclusions: This retrospective study adds to the limited literature exploring alternative therapies for complicated and MDR UTIs with results providing additional evidence that fosfomycin may be an effective oral option.

UroPathogenic Escherichia coli (UPEC) Infections: Virulence Factors, Bladder Responses, Antibiotic, and Non-antibiotic Antimicrobial Strategies

“…Antimicrobial prophylaxis for women with recurrent UTI include, for example, 50 mg or 100 mg of nitrofurantoin once a day; 100 mg of Trimethoprim (TMP) once a day; 40/200 mg TMP/sulfamethoxazole (co-trimoxazole) once a day or three times a week; 3 g of fosfomycin trometamol every 10 days and, during pregnancy, for example, 125–250 mg of cephalexin or cefaclor 250 mg once a day (Grabe et al, 2015 ; Giancola et al, 2017 ). Among other antibiotics, imipenem represents the best efficient antibiotic against all UPEC strains (100%), followed by ertapenem (99.98%), amikacin (99.94%), and nitrofurantoin (99.91%).…”

Oral and Intravenous Fosfomycin for the Treatment of Complicated Urinary Tract Infections

“…In 2017, Giancola et al published a retrospective evaluation that included 57 patients (19 males, 38 females; median age 79 years) with complicated and/or MDR UTI treated with ≥1 dose of oral fosfomycin [12]. All patients in the study had signs and symptoms of UTI and a positive urine culture.…”

“…To our knowledge, a total of ten studies have been published investigating the use of oral fosfomycin in the treatment of cLUTI [4][5][6][7][8][9][10][11][12][13]. It is important to note that these studies varied in their definitions of "complicated" LUTI.…”

Pharmacodynamic Evaluation of Fosfomycin against Escherichia coli and Klebsiella spp. from Urinary Tract Infections and the Influence of pH on Fosfomycin Activities

“…However, for more complicated UTI cases (for which fosfomycin is not approved), multiple doses have been used. In parts of the world, including Brazil, where intravenous fosfomycin is not available, interest in regimens with multiple doses of oral fosfomycin for treating complicated UTIs and related infections has been renewed (3,4).…”