Prevalence of Acinetobacter baumannii bacteremia in intensive care units of Ibn Rochd University Hospital, Casablanca

Acinetobacter baumannii bacteremia are grave because of the multi-resistance of the organism to antibiotics. This study aimed to determine the prevalence of A. baumannii isolated from blood cultures and to describe their antibiotic resistance patterns.
A retrospective longitudinal study was conducted on blood cultures between 2010 and 2014 from all Ibn Rochd University Hospital intensive care units; it was based on the exploitation of microbiology laboratory database (duplicates were excluded). Isolation and identification of A. baumannii were performed according to standard techniques of bacteriology and susceptibility testing as recommended by the CLSI. PCR was used to detect β-Lactamase genes,
blaOXA-51, blaOXA-23.
Among the 4232 samples received at the laboratory, 2402 (56.8%) were positive. Negative coagulase Staphylococcus was isolated in 21.6% of cases followed by A. baumannii (9.2%), and K. pneumoniae (9.1%). A. baumannii strains were resistant to most antibiotics tested: imipenem (75.7%), ceftazidim (85.4%), cefotaxim (98.6%), gentamicin (78.1%), amikacin (63.5%) and ciprofloxacin (88.2%). All A. baumannii strains, resistant to carbapenem, tested were positive for blaOXA-51 genes and 87.5% expressed the blaOXA-23 genes.
A. baumannii was the second germ frequently isolated from blood cultures in intensive care units. It was multi-resistant to antibiotics. The strengthening of hospital hygiene measures and surveillance of antibiotic resistance is needed to limit the spread of germs and to optimize the management of antibiotics.