Day of surgery urine cultures identify urogynecologic patients at increased risk for postoperative urinary tract infection

Purpose: Despite preoperative screening and treatment for urinary tract infections, a postoperative urinary tract infection develops in approximately 1 in 5 urogynecologic patients. In this study we assess the proportion of urogynecologic patients with a positive day of surgery urine culture, the clinical consequences of a positive day of surgery culture and differences in postoperative urinary tract infection risks based on day of surgery culture. Materials and Methods: After institutional review board approval, patients undergoing urogynecologic surgery at Loyola University Medical Center were recruited for the study. Catheterized urine samples were collected in the operating room before intravenous antibiotic administration. Clinical cultures were considered positive if 1,000 colonies per ml or more bacteria were found on routine culture. For analysis we matched each woman with a positive culture with 2 women with negative culture by age within 10 years and within surgical groups (ie prolapse and/or incontinence). Data were analyzed using SPSS® version 19. Results: Nearly a tenth (9.5%) of participants had positive day of surgery cultures. The clinical and demographic characteristics were similar in women with negative vs positive day of surgery cultures. However, women with positive day of surgery cultures were more likely to experience a postoperative urinary tract infection despite standard perioperative antibiotic administration (29.6% vs 5.6%, p = 0.005, odds ratio 7.2). Regardless of day of surgery culture status no participant experienced postoperative systemic urinary complications. Conclusions: Nearly a tenth of urogynecologic patients had positive day of surgery cultures. Patients with a positive day of surgery culture had an increased risk (29.6%) of postoperative urinary tract infection within 6 weeks of surgery. These findings highlight an opportunity to identify and treat patients with positive day of surgery cultures and reduce the incidence of postoperative urinary tract infections.