INCIDENCE AND DETECTION OF METALLO-BETA-LACTAMASE PRODUCING KLEBSIELLA PNEUMONIAE IN A TERTIARY CARE HOSPITAL

Dr. Atul Khajuria* and Ashok K. Praharaj, MD

ABSTRACT

Objective: To examine the distribution, emergence and spread of genes encoding beta-lactamase resistance in Klebsiella pneumoniae recovered from hospitalized patients in a tertiary care hospital. Methods: A prospective study was conducted in an 1800 bedded tertiary care centre in Pune, India from October 2013 to October 2017. A total of 659 isolates were recovered from clinical specimens of hospitalized patients admitted to the Medical and Surgical intensive care units (one isolate per patient). Polymerase chain reaction (PCR) assays and sequencing was used to determine the presence of beta-lactamase encoding genes and conjugation experiments were performed to determine the transferability. Isolate relatedness were determined by REP PCR, ERIC PCR and RAPD. Results: A total of 659 K.pneumoniae isolates were recovered, largest proportion of specimens were from UTIs 30%, followed by 25% in SSTIs, 21.3% in BSIs, 16% in RTIs, and 8% in IAIs and Misc. respectively. Among 659 tested isolates, 32.8% isolates showed MIC >4μg/ml against imipenem and meropenem. Of the total number of samples, males contributed 68.1% while females contributed 31.9%. Of the total samples, highest 28.11% were from OBG, followed by 20.6% in surgery ward, 17.17% in ICU Surgery, 12.46% in Medicine ward and 10% in ICU Medical. Majority of Carbapenem resistant K.pneumoniae 28.83% were from UTIs, followed by 20% in SSTIs, 25.58% in BSIs, 19.4% in RTIs, and 6.51% in IAIs respectively. MHT was positive in 20.7%, DDST in 24.3%, CDST in 26.6%, and MBL (IP/IPI) E-test in 29.3% isolates. 100% K.pneumoniae isolates retained susceptible to colistin. Conjugation experiments indicated that blaNDM-1, blaVIM, blaOXA-48, blaSHV-5, blaSHV-11, blaSHV-12, blaSHV-28, blaCTX-M-15, blaCTX-M-14 were transferable via plasmid. Conclusion: This study highlights prevalence of blaVIM, blaOXA-48 and blaNDM-1, producing K.pneumoniae along with other β-lactamases genes carried on a single or multiple plasmids that serve as a driving force for the horizontal spread of carbapenem resistance. Running title- Metallo-beta-lactamase resistance in Klebsiella pneumonia.

Keywords: BlaNDM-1, blaVIM, blaSHV-5, blaSHV-11, blaSHV-12, blaSHV-28, blaCTX-M-15, blaCTX-M-14, REP PCR, ERIC PCR and RAPD.