DEVELOPMENT OF A MULTIPLEX PCR FOR DETECTION AND EVALUATION OF PREVALENCE RATE OF CTX-M-15, AADA1, QNRS1 GENE AMONG ENTEROBACTERIACEAE FROM CLINICAL ISOLATES

Abstract

Objective: To design and standardize a multiplex Polymerase chain reaction (PCR) targeting ctx-m-15, aadA1, QnrS1 gene among Enterobacteriaceae from clinical isolates. To evaluate the prevalence rate of these genes among clinical isolates recovered from a primary hospital at Kanchipuram district, Tamil Nadu, India.Methods: All clinical specimens, culture positive for Enterobacteriaceae (n=60) isolated from blood, urine, sputum submitted to CSI Mission Hospital, Kanchipuram, Tamil Nadu from December 2014 to March 2015 were identified by standard ṃicrobiological procedures. Designing of novel primers targeting ctx-m-15, aadA1, QnrS1 gene carried out using primer3 tool, and the procured primer has been standardized for multiplex PCR using PCR-DNA sequencing confirmed clinical isolates of the respective genes.Results: Of the 60 clinical isolates studied, 14, 13 and 12 isolates harbored ctx-m-15, qnrS1 gene, and aadA1genes respectively. In which 2 isolates carried both ctx-m-15 and qnrS1 gene and 3 isolates were found to carrying both ctx-m-15and aadA1 gene and 1 isolate was found to be positive for both aadA1and qnrS1 gene. None of the isolates harbored all the three genes qnrS1 aadA1 and ctx-m-15.Conclusion: The present study will aid in detecting drug-resistant genes like ctx-m-15, aadA1, QnrS1 in clinical isolates with higher sensitivity and specificity. Since, multiplex PCR will reduce the cost of a reaction than uniplex PCR, which is very essential for both scientific and social community. The prevalence rate of these three drug resistance gene among clinical isolates from Kanchipuram district alert us for the measures needs to be undertaken to control the spread of drug resistant genes among other districts and community.