First Report of Extended-Spectrum β-Lactamases Among Clinical Isolates of <i>Klebsiella pneumoniae</i> in Gaza Strip, Palestine

Abstract

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 β-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 IS Ecp1 (in four cases truncated by IS 26 ), orf477 , or IS 903 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.