Direct medical costs of urinary tract infections by gram-negative bacilli resistant to Beta-lactams in a tertiary care hospital, Medellín, Colombia

Abstract

Introduction: Urinary Tract Infections (UTIs) have a high frequency of occurrence in the hospital environment and, due to the emergence of antimicrobial resistance, have caused care processes to become more complex, putting additional pressure on available healthcare resources. Objective: To describe and compare the excess direct medical costs of UTIs due to K. pneumoniae, E. cloacae and P. aeruginosa resistant to beta-lactams. Materials and methods: A cohort study was conducted in a third level institution in Medellín, Colombia, from October 2014 to September 2015. It included patients with UTIs by beta-lactam-susceptible bacteria, 3rd and 4th generation cephalosporins-resistant, and carbapenem-resistant. Costs were analyzed from the perspective of the health system. Clinical-epidemiological information was obtained from medical records and the costs were calculated using standard tariff manuals. Excess costs were estimated with multivariate analyzes. Results: 141 patients were included, 39% of which were sensitive to beta-lactams, 38.3% resistant to cephalosporins and 22.7% resistant to carbapenems. The excess total adjusted costs of patients with UTIs due to resistant bacteria-cephalosporins and carbapenems were US$193 [95% confidence interval (CI) US$-347-734] and US$633 [95% CI US$-50-1316) respectively, compared to the group of patients with beta-lactam sensitive UTIs. The differences were mainly found in the use of broad-spectrum antibiotics such as meropenem, colistin and fosfomycin. Conclusion: The results of the srudy show a substantial increase in the direct medical costs of patients with UTIs caused by Beta-lactam-resistant gram-negative bacilli (cephalosporins and carbapenems). This situation is of particular concern in endemic countries such as Colombia, where the high frequencies of UTIs and resistance to Beta-lactam antibiotics can generate a greater economic impact on the health sector.