Molecular determinants of ß-lactamase producing Klebsiella pneumoniae in Mansoura University Neonatal Intensive Care Unit


  • Enas Hammad Faculty of Medicine, Mansoura University, Egypt
  • Hamdia Askar
  • Mohammed Saleh
  • Basma Shouman



K. pneumoniae, ESBL, Egyptian neonates.


Background: The emergence of ß-lactamase- producing Klebsiella pneumonia (K. pneumoniae), represents a significant diagnostic and therapeutic challenge to the management of infections caused by this organism. This prospective study aimed at studying the frequency of ß-lactamase production by K. pneumoniae in neonatal intensive care unit (NICU) of Mansoura University Children’s Hospital.

Methods: This prospective study was conducted over a period of thirty six months from September 2010 to August 2013, where 684 samples were collected from different body sites of neonates in the NICU. Microbial isolation, identification and antimicrobial susceptibility testing were carried out.  ß-lactamase production by K. pneumoniae isolates was tested by phenotypic methods and PCR amplification of related genes using a six-gene panel for the amplification of the blaCMY-2, blaDHA, blaACC, blaSHV, blaTEM and blaCTX-M genes. In vitro transformation and conjugation were carried out to test for plasmid mediated AmpC ß- lactamase resistance transmission to E. coli.

Results: K. pneumoniae was isolated at a percentage of 12.6% and ß-lactamase production was detected in 62.8% of the isolates.  The most commonly detected ß-lactamase gene was blaSHV (51.9%), followed by BlaCMY-2 (16.67), blaDHA (12.96%), blaTEM (9.2%), blaCTX- M(7.4%) and lastly blaACC (1.85%). Additionally, some strains carried combinations of two or three genes. The plasmid carrying blaCMY-2 was 100% successfully transformed into the competent E. coli LE392 while conjugation with the E. coli ATCC 25922 was (77.8%) successful.

Conclusion: K. pneumoniae is a common multidrug resistant isolate; the production of ß-lactamases is the mechanism of resistance in a significant number of cases and represents a real risk for failure of many therapeutic options. This problem is highly complicated by the horizontal spread of resistance plasmids among microbial population.

Author Biography

Enas Hammad, Faculty of Medicine, Mansoura University, Egypt

Medical Microbiology and Immunology Department

Faculty of Medicine

Mansoura University


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