Prevalence and diversity of bla TEM, bla SHV and bla CTX-M variants among multidrug resistant Klebsiella spp. from an urban riverine environment in India.

In the present study, we have investigated prevalence and diversity of ESBL genes among Klebsiella isolates obtained from highly polluted stretch of river Yamuna, India. Phenotypic screenings of 116 Klebsiella isolates revealed ~30% were positive for ESBL production. Antibiotic profiling showed multidrug resistance phenotype among 90% isolates. Prevalence of bla TEM, bla SHV and bla CTX-M genes were found to be 57, 54 and 48% respectively. Furthermore, we identified eight variants of bla SHV (SHV-1, SHV-11, SHV-27, SHV-28, SHV-38, SHV-61, SHV-144, SHV-148), three each of bla TEM (TEM-1, TEM-116, TEM-206) and bla CTX-M (CTX-M-15, CTX-M-55, CTX-M-188) among Klebsiella spp. Co-occurrence of bla TEM, bla SHV and bla CTX-M (any two or all three) was observed among 45% Klebsiella isolates. Occurrence of bla CTX-M-188 and bla TEM-206 in environmental isolates of K. pneumoniae has not been reported earlier. Identification of bla TEM-206, bla SHV-27 and bla SHV-144 from Klebsiella spp. and bla TEM-116 from K. quasipneumoniae and K. variicola is the first report from India.