MOLECULAR DETECTION OF bla NDM-1 GENE IN BACTERIA CAUSING URINARY TRACT INFECTIONS

Abstract

In healthcare system, antibiotic resistance has been an increasing problem. New Delhi Metallo-p lactamase 1 (NDM-l), a novel Metallo-p-lactamase reported for the first time in 2008 in K. pneumonia was isolated from a patient in India. This novel enzyme (NOM-I) enables the bacteria to resist wide range of beta-lac tam antibiotics by hydrolyzing them and inactivating their activity. In Pakistan, there is no adequate data available to estimate the updated prevalence of NDM-l positive pathogens causing Urinary Tract Infections (UTIs). This study was conducted to detect the prevalence of blaNDM-1 gene in bacterial isolates causing UTI. A total of 130 Gram negative isolates were collected from UTI samples submitted to two tertiary care hospitals; Pakistan Institute of Medical Sciences (PIMS), Islamabad and Mayo hospital Lahore. These isolates were further confirmed by conventional biochemical tests. Out of 130 isolates, the majority were collected form PIMS (n=75) among which dominant microorganisms were E coli (41.5%), K. pneumoniae (22.2%) P. aeruginosa (20.2%), Proteus spp. (12.1 %) and Enferobacler spp (4%) while 55 isolates were collected from Mayo Hospital, Lahore among which predominant were Ecoli (41%), P. aeruginosa (25%) K. pneumoniae (23%) and Proteus spp. (11 %). Most of the samples collected were from patients between the age range of> 4 1 years to <60 years. Metallo-beta-lactamase production in pathogens was screened by phenotypic combine disk method and Modified Hodge Test (MHT). Out of 130 isolates, 68 (52.3%) isolates were carbapenem resistant while 42 (32.3%) showed both carbapenamase and MBL production and 20 (15.4%) were Non-carbapenamase and MBL producers. Molecular detection of blaNDM-1 gene was carried out through peR amplification which demonstrated the presence of blaNDM-1 gene in 7 (16.6%) out of 42 MBLs producing pathogens. Among these, three microorganisms were identified as P. aeruginosa, two as E coli and two as K. pneumoniae (n=2). In conclusion, the study reveals a high rate of antimicrobial resistance and NDM- l positive microorganisms in UTI patients. Therefore a surveillance study should be implemented in different hospitals of Pakistan, and up-to-date information is required to know the exact prevalence of this MBL in pathogenic strains causing UTI.