Rectal carriage of extended-spectrum β-lactamase- and carbapenemase-producing Enterobacteriaceae among hospitalised neonates in a neonatal intensive care unit in Fez, Morocco.

OBJECTIVES

The aim of this study was to investigate the faecal carriage and molecular epidemiology of extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae (ESBLE) isolated from rectal samples of neonates hospitalised in a neonatal intensive care unit (NICU) of a university hospital in Fez, Morocco.

METHODS

From February-July 2013, all neonates hospitalised in the NICU were screened for ESBLE carriage at discharge. ESBLs were identified by double-disk synergy test, PCR and DNA sequencing analysis. ESBLE were analysed by pulsed-field gel electrophoresis (PFGE), and conjugation was performed by the broth mating method.

RESULTS

In this study, 169 Enterobacteriaceae were collected from 164 neonates. The prevalence of faecal carriage of ESBLE was 58.0% (98/169), predominantly Klebsiella pneumoniae (65/98; 66.3%). A high rate of multiresistance in ESBLE was noted. bla group (78.5%) was the most frequent ESBL gene detected, and all isolates harboured the CTX-M-15 variant. The prevalence of carbapenemase-producing Enterobacteriaceae was 1.8%, and bla was the only gene found in these isolates. Sequencing revealed subgroups corresponding to bla genes. Conjugation experiments showed the transferability of bla and bla, but not bla. These genes were carried by a high-molecular-weight conjugative plasmid (ca. 125kb). PFGE profiles demonstrated high clonal dissemination of ESBL-positive strains in the NICU.

CONCLUSIONS

These results demonstrate the existence of high clonal transmission of ESBLE in a Moroccan NICU. This finding provides useful information to implement a screening policy for resistant Enterobacteriaceae among neonates hospitalised in this ward.