Salazar JG, et al. - Researchers investigated how routine screening and treatment for asymptomatic bacteriuria, in patients undergoing orthopedic, cardiac, or vascular surgical procedures, are associated with postoperative outcomes. This national cohort study of 68,265 US veterans suggests no reduction in the risk for postoperative infections, including urinary tract infection (UTI) and surgical-site infection (SSI), in association with receipt of antimicrobial therapy with activity against asymptomatic bacteriuria (ASB) organisms identified in preoperative urine cultures. Findings thereby do not support the practice of screening and treatment for preoperative ASB.

Methods

• Researchers performed this retrospective cohort study involving patients, predominantly male veterans, who underwent surgical procedures in 109 US facilities within the US Department of Veterans Affairs health care system from October 1, 2008, to September 30, 2013.
• Patients (n = 68 265) who had cardiac, orthopedic, or vascular surgical procedures were included as participants.
• In each patients, a planned clinician review of complete medical records for antimicrobial prophylaxis as well as 30-day SSI and UTI outcomes was performed; each patient had a preoperative urine culture result available within the 30 days prior to the procedure.
• They analyzed data from December 2016 to August 2018.
• The association between preoperative ASB and postoperative SSI was the primary outcome assessed.
• Postoperative UTI and the association between antimicrobial therapy for ASB and postoperative infectious outcomes were included as the secondary outcome measures.

Results

• Researchers identified 68,265 patients (65,664 [96.2%] were men and 2601 [3.8%] were women, with a mean [SD] age of 64.6 [9.2] years); of these, 17,611 (25.8%) were eligible for inclusion in the primary analysis.
• Performing preoperative urine cultures in 17,749 (26.0%) patients, they identified 755 (4.3%) with positive results, of which 617 (81.7%) were classified as ASB.
• With adjustments for age, American Society of Anesthesiologists class, smoking status, race/ethnicity, sex, and diabetes status, similar odds of SSI were noted among patients with or without ASB (2.4% vs 1.6%; adjusted odds ratio [aOR], 1.58; 95% CI, 0.93-2.70; P=.08).
• No reduction in SSI was noted in association with receipt of antimicrobial therapy with activity against the ASB organism (aOR, 1.01; 95% CI, 0.28-3.65; P=.99).
• Fourteen (3.3%) of 423 patients with ASB and 196 (1.5%) of 12,913 patients without ASB suffered urinary tract infection (aOR, 1.42; 95% CI, 0.80-2.49; P=.22).
• Similarly no association of treatment or prophylaxis for the ASB organism was noted with reduced odds of postoperative UTI (aOR 0.68; 95% CI, 0.20-2.30; P=.54).
• In 2 cases, the ASB organisms matched a postoperative wound culture, both Staphylococcus aureus.