Over the last decade, many studies have shown increasing rates of infection following ultrasound-guided transrectal prostate needle biopsies (TRUSPBs).
To evaluate the effectiveness of fosfomycin tromethamine prophylaxis in preventing post-TRUSPB infectious complications, we conducted a case-control study nested in a cohort of patients undergoing TRUSPB between 2002 and 2016 in a secondary and tertiary care hospital in Canada. It included patients who developed post-TRUSPB bacteremia and/or urinary sepsis. Controls were randomly selected from among TRUSPB patients without such complications. Four prophylaxis periods were defined across the study: i) ciprofloxacin, low-resistance period (CIPRO-LOW), 2002–2009; ii) ciprofloxacin, high-resistance period (CIPRO-HIGH), 2010–October 2013; iii) oral fosfomycin tromethamine, one dose (FOSFO1), December 2013–September 2015; and iv) oral fosfomycin tromethamine, two doses (FOSFO2), October 2015–June 2016. Incidence rates of infection were calculated from the cohort. Crude and adjusted odds ratios and their 95% confidence intervals were calculated using logistic regression, using the nested case-control study.
During the study, 9527 TRUSPBs were performed, resulting in 138 cases of urinary sepsis (58% with bacteremia). The incidence rates were 1.82% with CIPRO-HIGH, 3.54% with the FOSFO1 regimen (p=0.004, compared to CIPRO-HIGH), and 2.73% with the FOSFO2 regimen (p=0.19, compared to CIPRO-HIGH).Patients receiving FOSFO1 (risk ratio: 2.18; p=0.0001) and FOSFO2 (risk ratio: 1.84; p=0.05) had a higher risk of hospitalization for a post-TRUSPB infectious complication than patients receiving CIPRO-HIGH did. Although Escherichia coli remained the predominant pathogen with fosfomycin-based regimens, the proportion of infections with Klebsiella spp. was significantly higher (20/66; 30.3%) than that with ciprofloxacin-based regimens (2/77; 2.5%; p<0.0001). Independent risk factors for infection were the prophylactic regimen administered, the presence of urological comorbidity, and diabetes.
Fosfomycin tromethamine was not an effective alternative to ciprofloxacin for preventing post-TRUSPB urinary sepsis, highlighting the need for novel antibacterial prophylaxis approaches.
L. P. Montpetit,
R. Sabbagh, None
M. A. Smith, None
M. Raymond, None
C. Allard, None
A. Carignan, Paladin Labs: Speaker's Bureau , Speaker honorarium