Susceptibility trends and molecular characterization of Gram-negative bacilli associated with urinary tract and intra-abdominal infections in Jordan and Lebanon: SMART 2011–2013

•We report resistance trends in Gram-negative bacilli from Jordan and Lebanon.•Urinary tract and intra-abdominal infections occurring between 2011 and 2013 were followed.•The overall incidence rate of extended-spectrum beta-lactamases (ESBLs) among pooled Gram-negative bacilli was 44%.•CTX-M-15 was the most prevalent ESBL, with many isolates producing multiple enzymes.•The prevalence of carbapenem-non-susceptible Enterobacteriaceae was 1.6%.

SummaryObjectivesTo investigate phenotypic and genotypic patterns of antimicrobial resistance among Gram-negative bacilli associated with urinary tract infection (UTI) and intra-abdominal infection (IAI) in medical centres of Jordan and Lebanon.MethodsGram-negative bacilli from the SMART study, collected between the years 2011 and 2013, were first identified at local laboratories. These isolates were shipped to a central laboratory where re-identification, susceptibility testing, and molecular characterization were performed using standard methods.ResultsAmong the 523 UTI-associated isolates, Escherichia coli, Klebsiella pneumoniae, and Proteus mirabilis were the most frequent (70%, 14%, and 5%, respectively). E. coli, K. pneumoniae, and Pseudomonas aeruginosa were the most frequent species among the 527 IAI-associated isolates (46%, 14%, and 12%, respectively). Incidence rates of extended-spectrum beta-lactamase (ESBL) producers among UTI-associated E. coli, K. pneumoniae, and P. mirabilis were 43%, 54%, and 4%, respectively. Corresponding rates among IAI-associated isolates were 49%, 56%, and 12%, respectively. Acinetobacter baumannii and P. aeruginosa isolates showed very disturbing low susceptibility patterns. CTX-M-15 was the most prevalent ESBL produced. Seventeen isolates were non-susceptible to carbapenems (estimated prevalence of 1.6%).ConclusionsThe alarmingly high rates of ESBL production and emergence of carbapenemases emphasize the urgent need to develop antimicrobial stewardship initiatives and to maintain antimicrobial resistance surveillance systems.