Occurrence of extended spectrum beta-lactamases among clinical bacteria isolated from Daura General Hospital, Katsina State, Nigeria

Abstract

Background: Bacterial resistance to antibiotics is a major global challenge in the diagnosis and treatment of infectious diseases. ESBLs are enzymes that confer resistance to third and fourth generation cephalosporins that are produced to counter resistance to normal betalactamase enzymes.

Aim: This work was aimed at detecting the occurrence of ESBLs among clinical bacterial isolates at the study site.

Methods: Three hundred and ninety nine (399) Gram negative bacterial isolates were collected from the study site and identified using standard biochemical tests. The isolates were screened for ESBLs using Clinical Laboratory Standards Institute (CLSI) breakpoint and confirmed using Double Disc Synergy Test (DDST). The standard antibiotic discs used were augmentin (AMC 30μg), cefotaxime (CTX 30μg) and ceftazidime (CAZ 30μg) [Oxoid, England].

Results: The results of CLSI breakpoint test showed that 206 (51.62%) were positive for ESBLs which include; Proteus spp 88(22.05%), E. coli 40(10.02%), Klebsiella spp 48(12.03%), Citrobacter spp 18(4.51%), Providencia spp 4(1.01%), Shigella spp 6(1.50%), Salmonella spp 2(0.50%). ESBLs confirmation using DDST revealed that 119 (57.76%) were positive for ESBL production viz; Proteus spp 66(32.04%), E. coli 8(3.88%), Klebsiella spp 28(13.59%), Citrobacter spp 12(5.82%), Providencia spp 2(0.97%), Shigella spp (31.46%), Salmonella spp 0 (0.00%) giving an overall ESBLs occurrence of 29.82%.

Conclusion: The high occurrence of ESBLs observed among the clinical isolates implies that the enzymes occur at an alarming rate which may lead to high patient mortality due to treatment failure.