PREVELANCE OF CARBAPENEMASE PRODUCING ORGANISMS AND MOLECULAR RAPID DETECTION OF DIFFERENT GENES FROM VARIOUS CLINICAL ISOLATES IN PATIENTS ADMITTED AT TERTIARY CARE HOSPITALS OF VADODARA
Authors: Rajyaguru Bhoomika , Trivedi Urmi 
Published: June 2023

Introduction- Carbapenemase-producing organisms (CPO) have been identied as an urgent healthcare threat. The spread of carbapenemase-producing Enterobacterales (CPE) is a global health problem of great concern. Rapid detection of carbapenemase-producing organisms is clinically desirable for hospital infection control and antibiotic stewardship. Recently, an on-demand polymerase chain reaction (PCR) assay, namely, the Xpert CarbaR assay, that requires less than an hour of turnaround time, had been developed for CPO detection in clinical samples to identify and guide infection control programs to contain the spread of CPO within a hospital. Objective- Carba-R assay is a qualitative multiplex real-time PCR method that qualitatively detects and differentiates ve common carbapenemase genes blaKPC, blaNDM, blaVIM, blaOXA-48, and blaIMP) directly from clinical samples or puried colonies within approximately 1 hour. This benets hospitals and patients by facilitating timely Infection Prevention & Control measures, thereby reducing risk of exposure, transmission and bed-days lost. Materials & Methods- In this study, the Xpert Carba-R assay was evaluated for detection of the ve carbapenemase genes (blaKPC, blaNDM, blaIMP, blaOXA-48, and blaVIM) in total of 40 non duplicate various clinical samples of admitted patients in tertiary care hospitals of Vadodara. Result- We performed Carba-R on 40 isolates: 18 blood samples, 06 urine, 05 rectal swabs, 03 Endotracheal secretion, 03 Pus, 02 wound discharge, 01 Bronchoalveolar lavage uid, 01 sputum, and 01 ERCP stent isolates. 36/40 (90%) isolates had one or more carbapenemase genes. They were as follows: 19/40 (47.5%) both OXA48 and NDM , 12/40 (30%) NDM and 05/40(12.5%) OXA-48. There were 04/40 (10 %) isolates which were Carbapenem resistant on disc diffusion & VITEK but none of the resistant genes were detected possibly due to other resistant mechanism like efux pump and porin channels. Klebsiella pneumoniae was the most common isolate with CR, 34/40 (85%). The most frequent genes encountered in Klebsiella pneumoniae were both OXA48 and NDM, 19/34 (55.88%), NDM 08/34 (23.53%) followed by OXA 48, 05/34 (14.71%) and Out of 34 Klebsiella isolates, 02 isolates failed to detect any of these ve carbapenemase genes. Conclusion- Xpert Carba-R assay provides good reliable results for detection and differentiation of ve carbapenemase genes in clinical isolates. Compared to bacterial culture followed by PCR identication of resistance genes from colonies, the Carba-R assay reduced turnaround time from 48 to 72 hours to less than 1 hour. Carbapenemase genes were detected by the Carba-R assay in Klebsiella pneumoniae (34/40), Escherichia coli (5/40), Acinetobacter spp (1/40). The Carba-R assay detected 19 both OXA48 and NDM (47.5%), 12 blaNDM (30% and 05 blaOXA-48 (12.5%) genes. Laboratory detection of these genes may help improve patient outcomes by tailoring therapy. This study was conducted for understanding the molecular epidemiology of Carbapenemase producing Enterobacteriaceae in a tertiary care hospital. The combined use of the Xpert Carba-R assay and culture produces rapid and reliable results for the active surveillance of CPO in patients