Urinary Tract Infections after Extracorporeal Shock Wave Lithotripsy

Abstract

Extracorporeal shock wave lithotripsy (ESWL) has been using since a long time in the treatment of urolithiasis; until now it is not universally stated if such a procedure represents a risk factor for the development of complications (such as pyelonephritis) and if the same procedure needs an antimicrobial prophylaxis. We began a prospective study in order to evaluate the clinical and microbiological follow-up of all the patients undergoing ESWL at the Centre of urologic lithotripsy of the University of Pisa into a two months period. Methods Fifty-four consecutive patients were enrolled (38 males and 16 females). All the patients were studied, examining their urine samples before ESWL and after one week and evaluating their risk factors for urinary tract infections. Results 12 (22.2 %) out of 54 patients had a significant bacteriuria (≥ 104 CFU/mL) before undergoing ESWL; such bacteriuria persisted in eight of the twelve patients even though they received an appropriate antimicrobial therapy. 41 (75.9%) patients without a significant bacteriuria at the enrollment remained asymptomatic –with sterile urine- after ESWL and they did not receive therapy. One patient with multiple stones, who had a clinical history of previous urinary infections, developed an acute pyelonephritis after ESWL when she stopped the antibiotic terapy. Conclusions Such preliminary data seem to show that the risk of developing urinary infections after ESWL is represented primarily by a history of previous urinary infections and by the presence of an asymptomatic urinary tract infection before ESWL. The decision about the need of an antimicrobial prophylaxis should be taken in every single case basing on the peculiar clinic history of the patient.