The Efficacy of Fosfomycin as Antibiotic Prophylaxis for Transrectal Prostate Biopsy and Impact on Lower Urinary Tract Symptom After Biopsy: A Prospective Study

Objective: Due to fluoroquinolone resistances worldwide, valid alternatives for antibiotic prophylaxis for transrectal ultrasound-guided prostate biopsy are needed, thus, we aimed to evaluate the efficacy, safety, and tolerability of prophylactic fosfomycin versus other oral prolonged antibiotic regimens, in preventing complications after transrectal ultrasound-guided prostate biopsy. Methods: In this prospective study, patients submitted to transrectal ultrasound-guided prostate biopsy were divided into 2 groups according to the prophylactic antibiotic scheme performed: "short" (2 fosfomycin doses) versus "long" (antibiotic >= 8 days). One week and 1 month after transrectal ultrasound-guided prostate biopsy, we assessed complications' occurrence (lower urinary tract symptoms, fever, sepsis, hemorrhage) and adverse drug reactions. Results: We included 244 patients (fosfomycin n=178, "long" antibiotic n=66). The only significant difference between groups was higher lower urinary tract symptom incidence 1 month after transrectal ultrasound-guided prostate biopsy in fosfomycin patients (16.85% vs. 6.06%, P=.031). However, after 1 week, lower urinary tract symptoms were tendentially frequenter on "long" antibiotic group (31.81% vs. 25.84%, P=.059). Infectious and hemorrhagic complications rate, adverse drug reactions, and recurrence to health services were similar between groups, and significantly decreased between the first week and first month. Conclusion: Antibiotic prophylaxis seems to impact lower urinary tract symptoms after transrectal ultrasound-guided prostate biopsy. Fosfomycin may provide slightly better outcome on the immediate period, while "long" antibiotic courses lead to significantly less lower urinary tract symptoms 1 month post-transrectal ultrasound-guided prostate biopsy, perhaps by preventing incipient prostatitis phenomena. Future directed studies should clarify these findings. Still, it seems feasible to ally fosfomycin advantages with noninferior safety, efficacy, and tolerability, allowing to reserve "long" regimens to other contexts. This is especially relevant in centers where transperineal biopsies are still not possible.