Prebiopsy bacteriuria does not appear to increase the risk for infectious complications following prostate needle biopsy (PNB), a new study suggests.
“Routine office urine culture in the asymptomatic male prior to PNB is unnecessary,” Jay D. Raman, MD, of Pennsylvania State University and colleagues concluded in International Urology and Nephrology (2018;50:21-24).
Of 150 men who had urine cultures 14 days before PNB, just 6 (4%) had asymptomatic bacteriuria of more than 10,000 colony forming units (CFU) per mL. Two men were infected with Escherichia coli of more than 100,000 CFU/mL; 1 with Klebsiella of more than 100,000 CFU/mL; one with E. coli of 10,000 CFU/mL; and 2 with mixed flora of 10,000 CFU/mL. None of the infected patients received dedicated treatment, per the study protocol.
All patients then received usual antibiotic prophylaxis, including 500 mg ciprofloxacin the night before and the morning of the biopsy. Repeat urine cultures immediately before biopsy yielded an overall mean bacterial count of 55 CFU/mL. The 6 patients with prebiopsy infection each had less than 100 CFU/mL, indicating their infections had resolved.
Post-biopsy infection developed in 4 patients (2.7%), including 2 with sepsis and 2 with confirmed urinary tract infections. Quinolone-resistant E. coli was responsible for all cases. Post-biopsy infection did not develop in any of the 6 patients who had a positive office urine culture 2 weeks prior to biopsy.
The American Urological Association recommends fluoroquinolones for antibiotic prophylaxis prior to biopsy. “This class of antibiotic has great efficacy in urine and prostate tissue, with broad coverage of both gram-positive and gram-negative organisms,” the authors wrote. “It is possible that the single dose received by patients in this study was sufficient for eradication of urinary bacteria.” They added that skipping treatment of asymptomatic men might help prevent post-biopsy infection by drug-resistant organisms.
Qi DZ, Lehman K, Dewan K, Kirimanjeswara G, Raman JD. Preoperative urine culture is unnecessary in asymptomatic men prior to prostate needle biopsy. Intl Urol Nephrol. 2018;50:21–24. doi: 10.1007/s11255-017-1752-2