First Report of Extended-Spectrum -Lactamases Among Clinical Isolates of Klebsiella pneumoniae in Gaza Strip, Palestine

Sixteen broad-spectrum cephalosporin-resistant Klebsiella pneumoniae isolates were recovered between April and June 2013 from Palestinian hospitals, Gaza Strip. Genes encoding extended-spectrum beta-lactamases (ESBLs) and other resistance genes were characterized by polymerase chain reaction and sequencing. The following -lactamase genes were detected: bla(CTX-M-15)+ bla(SHV1)+ bla(TEM-1) (six isolates), bla(CTX-M-15)+ bla(SHV5)+ bla(OXA-1) (two isolates), bla(CTX-M-14a) (two isolates), bla(CTX-M-15)+ bla(SHV33) (one isolate), bla(CTX-M-15)+ bla(TEM-1) (one isolate), bla(CTX-M-15)+ bla(SHV12)+ bla(OXA-1)(one isolate), bla(CTX-M-15)+ bla(SHV5) (one isolate), bla(CTX-M-15)+ bla(SHV1) (one isolate), and bla(CTX-M-3) (one isolate). The ISEcp1 (in four cases truncated by IS26), orf477, or IS903 sequences were found upstream or downstream of bla(CTX-M) genes. The aac(6)-Ib-cr gene was found in seven isolates. The qnrS1 and qnrB1 genes were detected in five isolates and two isolates, respectively. Seven isolates contained class 1 integrons with four gene cassette arrangements: dfrA5 (three isolates), dfrA12-orf-aadA2 (two isolates), dfrA17-aadA5 (one isolate), and aadA1 (one isolate). A high clonal diversity was also observed among studied isolates by pulsed-field gel electrophoresis (12 unrelated profiles). This study demonstrates for the first time the emergence and polyclonal spread of multidrug-resistant ESBL-producing K. pneumoniae isolates among patients in a hospital setting in Gaza Strip, Palestine.