Genotypic detection of metallo-Beta-Lactamases among multidrug resistant Klebsiella pneumoniae isolated from urine samples of UTI patients

Metallo-beta-lactamases producing bacteria are of public health concern, owning to the fact that bacteria that harbour genes for their production are notably resistant to several antibiotics. This study was carried out to genotypically investigate the prevalence of MBL-production in multidrug resistant K. pneumoniae isolated from urine samples of UTI patients attending a tertiary teaching hospital in Awka, Anambra State, Nigeria. Two hundred (200) mid-stream urine samples were collected from UTI patients, and were analyzed using standard microbiological procedures. Antibiotic susceptibility testing (AST) of the isolates was carried out using Kirby-Bauer disc diffusion method and combination disc test was employed to phenotypically screen the isolates for MBL production. The genotypic screening was performed by Polymerase chain reaction (PCR), using specific primers. Fifty-one (51) K. pneumoniae isolates were recovered from the urine samples. AST revealed that the isolates exhibited high resistance to Amoxicllin-clavulanic acid (100%), Ampiclox (98.04%), Imipenem (98.04%), Cefotaxime (96.08%), Cefuroxime (96.08%), Nitrofurantoin (70.59%), and were relatively susceptible to Ofloxacin (54.91%), Gentamycin (50.98%) and Levofloxacin (47.06%). A 79.02% of the K. pneumoniae isolates showed resistance to more than two classes of antibiotics, thus termed multidrug resistance strains. Of the 38 (41.76%) isolates of K. pneumoniae that were resistant to imipenem, 19 (20.88%) were confirmed as MBL-producers phenotypically, while 19 (20.88%) were non-MBL producers. Genotypically, blaVIM (21.98%) was the most detected MBL gene, followed by blaOXA-48 (18.68%) and blaIMP (15.38%). This study revealed the prevalence of multidrug resistant and MBLs producing K. pneumoniae in urine samples of the selected UTI patients.