Urinary tract infection by Acinetobacter baumannii and Pseudomonas aeruginosa: evolution of antimicrobial resistance and therapeutic alternatives

<b>Purpose.</b> <i>Acinetobacter baumannii</i> and <i>Pseudomonas aeruginosa</i> are responsible for numerous nosocomial infections. The objective of this study was to determine the development of their susceptibility to ten antibiotics and the antibiotic consumption of patients with suspicion of urinary tract infection (UTI).<b>Methodology.</b> A retrospective study was conducted on the susceptibility profiles of <i>A. baumannii</i> and <i>P. aeruginosa</i> isolates from 749 urine samples gathered between January 2013 and December 2016, and on the consumption of imipenem, meropenem and piperacillin-tazobactam between 2014 and 2016.<b>Results.</b> Hospital patients were the source of 82 (91.1 %) of the 90 <i>A. baumannii</i> isolates detected and 555 (84.2 %) of the 659 <i>P. aeruginosa</i> isolates. Globally, the lowest percentage susceptibility values were found for fosfomycin, aztreonam and ciprofloxacin, while colistin continued to be the most active antibiotic <i>in vitro</i>. In 2016, the susceptibility of <i>A. baumannii</i> to carbapenem and piperacillin-tazobactam decreased to very low values, while the susceptibility of <i>P. aeruginosa</i> to carbapenem remained stable but its susceptibility to piperacillin-tazobactam decreased. There was a marked increase in the consumption of piperacillin-tazobactam.<b>Conclusion.</b> In our setting, it is no longer possible to use carbapenems and piperacillin-tazobactam for empirical treatment of UTI due to <i>A. baumannii</i> or to use piperacillin-tazobactam for empirical treatment of UTI due to <i>P. aeruginosa</i>. Colistin was found to be the most active antibiotic <i>in vitro</i>. There was a marked increase in the consumption of piperacillin-tazobactam.