THE PORTRAYAL OF EXTENDED-SPECTRUM-β-LACTAMASES POSITIVE KLEBSIELLA PNEUMONIAE FROM DOMESTIC ANIMALS IN WEST BENGAL, INDIA, WITH THE EVALUATION OF THERAPEUTIC EFFICACY IN-VITRO

Abstract

A study investigated the antimicrobial resistance properties of Klebsiella pneumoniae strains positive for ESBL production, detected from raw milk and rectal swabs (N=199) of domestic animals, viz., cattle (52,30), sheep (10,40), and goats (27,40) collected from a few districts of West Bengal. Seventy-seven (38.69%) Klebsiella pneumoniae isolates were recovered that were confi rmed by PCR. The highest frequency of positive Klebsiella pneumoniae strains was found in rectal swab samples (50.91%) compared to milk samples (23.60%) collected from domestic animals. Thirty-fi ve (45.45%) K. pneumoniae samples were isolated phenotypically as ESBL producers, whereas 68 (88.31%) isolates were positive for the presence of any one of the targeted ESBL genes. The PCR detection of the genes responsible for ESBL activity revealed the highest prevalence of the blaCTX-M (54.54%) gene than the other two ESBL genes, blaSHV (53.25%) and blaTEM (22.08%). All three ESBLs were isolated at a greater frequency from rectal swabs than from milk samples. In PCR, the rectal swab positive samples (48) revealed the highest prevalence of the blaSHV gene (64.58%) than to the milk sample isolates (20, 50%). Isolation of the blaCTX-M gene (75%) from the milk sample isolates was more than that of the rectal swab isolates (56.25%), while blaTEM was isolated from both the rectal swab and milk sample 25%. Antibiogram of all the ESBL-producing Klebsiella pneumoniae isolates (n = 68) against 10 antibiotics showed 100% resistance towards ticarcillin/clavulanic acid and 80-90% resistance towards enrofl oxacin, amoxicillin, and cefi xime. While these bacteria were highly sensitive (100%) to imipenem EDTA, doxycycline, and other antibiotics like tetracycline, chloramphenicol, gentamicin, but co-trimoxazole showed maximum overall sensitivity (60-88%).