Extended-spectrum β-lactamase- and carbapenemase-producing enterobacteriaceae isolated from Egyptian patients with suspected blood stream infection

Abstract

Objectives: The aim of the study was to investigate the prevalence of extended-spectrum β-lactamase and carbapenemase production among Enterobacteriaceae isolated from Egyptian patients with suspected blood stream infection. Methods: Ninety-four Enterobacteriaceae blood culture isolates from Egyptian patients with suspected blood stream infection were collected, one isolate per patient. Identification of bacterial isolates was performed with MALDI-TOF (MS-based Vitek MS system, bioMerieux). Screening for ESBLs and carbapenemases production was done with the Vitek 2 system (bioMérieux). ESBL production was confirmed using the combined disk diffusion method for cefotaxime, ceftazidime, and cefepime, all with and without clavulanic acid (Rosco). Realtime PCR and sequencing were used to characterize the resistance genes. The phylogenetic groups of E. coli were identified by a PCR-based method. Results: Of the 94 Enterobacteriaceae isolates 46 (48.93%) showed an ESBL phenotype. One Enterobacter spp isolate was ESBL-producer and meropenem-resistant. The genetic analysis showed that CTX-M was present in 89.13% (41/46) of the ESBL-producing Enterobacteriaceae, whereas TEM and SHV were detected in 56.52% (26/46) and 21.74% (10/46) respectively (47.83%) of the ESBL-producing isolates were multidrug resistant (MDR). Eleven out of 30 ESBL-producing E-coli isolates were assigned to phylogroup B2, followed by groups B1 (8 isolates), A (6 isolates) and D (5 isolates). Conclusions: The high ESBL-E rates (48.93%) found in this study together with the identification of one carbapenem-resistant Enterobacter spp isolate is worrisome. Our results indicate that systems for monitoring and detection of ESBL-producing bacteria in Egyptian hospitals have to be established. Also strict hospital infection control policies with the restriction of the consumption of extended-spectrum cephalosporins are necessary.