Prevalence of Extended Spectrum Beta Lactamase Mediated Resistance to Antibiotics among Klebsiella Species in a Tertiary Care Hospital

Klebsiella endowed with plasmid mediated extended-spectrum b-lactamase (ESBL) enzymes continues to be a therapeutic challenge in the clinical settings. Hence an attempt was made to assess the prevalence of extended – spectrum beta lactamase (ESBL) producing Klebsiella in clinical isolates from outpatients and inpatients.

This prospective study was conducted in the Department of Microbiology at VIMS & RC. A total of 366 Klebsiella isolates were obtained from various clinical samples over a period of 6 months from out patients and in patients admitted into various wards and intensive care units. Klebsiella isolates were identified based on the microscopy, the colony morphology and the biochemical reactions according to the standard guidelines. Antimicrobial Susceptibility Testing was performed by modified Kirby Bauer's disc diffusion method. ESBL Detection was done using phenotypic confirmatory disc diffusion Test and double disc synergy test.

Klebsiella species was recovered from 366 clinical isolates of which 221 were from the out patients and 145 from inpatients. Klebsiella pneumoniae was the predominant isolate. 252 isolates (69%) were sensitive to 3rd-generation cephalosporins and 114 (31%) were resistant.

Amoxycillin showed the highest percentage of resistance (84%), cotrimoxazole (79%) and tetracyclins (75%). Highest sensitivity to imipenem (100%) followed by cefaperazone +sulbactum (82%), ceftriaxone (69%) was noticed. A total of 114 isolates (31%) positively expressed ESBL enzymes- 71(62%) were from inpatients and 43 (38%) from out patients. Among the 71 ESBL producing inpatient isolates 38 were from various ICUs. All ESBL-producing isolates were sensitive to imipenem, however high level resistance was demonstrated to other antibiotics used.

ESBL producing Klebsiella are highly prevalent in community and hospital settings, causing an alarming trend of multidrug resistance resulting in limited treatment options. This study highly recommends performing screening and confirmatory tests for ESBL detection in a routine diagnostic laboratory work.