Incidence of Extended-Spectrum Be-ta-Lactamase-Producing Klebsiella pneumoniae among Patients and in the Environment of Hassan II Hospital, Settat, Morocco

摘要

Aim: The aim of the current study is to determine: (1) the prevalence of extended-spectrum β-lactamase-producing K. pneumoniae (ESBL-Kp) isolated from clinical samples and a hospital environment in Hassan II Hospital (Settat, Morocco); (2) the associated risk factors of ESBL-Kp infections; (3) the link between clinical and environmental isolates. Methods: During the study period (April 2010 to March 2011), all patients infected and hospital environment sites contaminated by K. pneumoniae were considered as the potential study population and environmental site. The clinical data were collected to identify risk factors for ESBL carriage of K. pneumoniae infection. Screening of ESBL-and carbapenemase-producing isolates was performed by using a double-disk synergy test and the modified Hodge test, respectively. ESBL-Kp isolates were tested for the presence of genes encoding β-lactamases and were investigated by PCR. The clonal relationship between ESBL-producing isolates was analysed by ERIC- and REP-PCR method. Results: The overall prevalence of ESBL-Kp among clinical and environmental K. pneumoniae isolates was 35.13% (13/37) and 4.04% (4/99), respectively. The main risk factors for carrying ESBL-Kp were renal disease (46.15%), recent surgery (53.84%), previous hospitalisation (76.92%), and the presence of many invasive devices (53.84%). All ESBL isolates were multidrug resistant. The blaCTX-M group1and blaSHV (70.58% for each) were the most prevalent followed by blaTEM (52.94%). Thirteen strains expressed at least two bla genes. One isolate was positive in the modified Hodge test and was a blaOXA-48 producer. ERIC and Rep-PCR methods revealed an epidemic clonal dissemination of these isolates. Conclusion: The emergence of OXA-48 carbapenemase, endemic clonal dissemination and multi-drug resistance of ESBL-Kp isolates in our institution is highly alarming.