Cost of antimicrobial treatment of patients infected with multidrug-resistant organisms in the Intensive Care Unit.

This study aims to compare the costs of antimicrobial drugs used in the treatment of patients infected with multidrug-resistant organisms (MDRO) or those not infected with this type of organisms in an intensive care unit (ICU). It is a retrospective comparative case-control study, performed in a public hospital in the capital city of Brazil, comprising the years 2007, 2008 and 2009. Information on age, sex, length of hospitalization, clinical outcome, antimicrobial drugs, microorganisms and microbial sensitivity to antibiotics was collected. Spearman and Mann-Whitney tests were used for statistical analysis. The level of significance was set at p < 0.05. The sample consisted of 401 patients with a mean age of 51.36 years (± 19.68) being 226 (56.4%) male. As for the length of stay, 32.9% of the patients remained more than 20 days, with 195 discharged and 206 deaths. Global cost of antimicrobial treatment was US$ 1113 221.55 during the three year period. Treatment cost for patients with MDRO was higher than for those without (p = 0.010). At least one MDR strain was isolated in 54.6% of the patients. According to these results, nosocomial infections due to MDRO and the high costs involved may endanger the effectiveness of antimicrobial therapy in ICU and Health Centers.