Faecal carriage of CTX-M-15-producing Klebsiella pneumoniae in patients with acute gastroenteritis

Background & objectives: Data on extended-spectrum β-lactamases (ESBLs) produced by Gram-negative bacteria including Klebsiella pneumoniae especially molecular types of ESBL genes from India are limited. The present study was conducted to investigate the carriage and ESBL contents of multidrug-resistant K. pneumoniae recovered from patients with gastroenteritis in a rural village in southern India. Methods: Nine K. pneumoniae isolates obtained from 45 stool samples from patients with gastroenteritis from one rural and two urban sites, in southern India were included in the study. Antibiotic susceptibility testing, PCR analysis and sequencing were conducted to characterize the ESBL genes. Clonal relatedness was assessed by pulsed-field gel electrophoresis (PFGE). Results: All the isolates were found to be resistant to at least one of the third generation cephalosporins tested. All the study isolates were confirmed to produce ESBLs. PCR and sequencing revealed the responsible gene to be bla_CTX-M-15.bla_TEM and bla_SHV were absent. PFGE indicated that five of seven isolates from villagers were genetically closely related, and in turn were related to isolates from patients in two urban areas in this region. Interpretation & conclusions: Our findings showed that genetically-related isolates of K. pneumoniae producing CTX-M-15 were present in multiple areas in southern India. Larger studies need to be done in various geographical regions of the country to better define the molecular epidemiology of ESBL-producing K. pneumoniae and its clinical implications.