Abstract
Purpose: To investigate the antimicrobial susceptibility and extended spectrum β-lactamase (ESBL) production by clinical isolates of Escherichia coli (ESBL-EC) and Klebsiella species (ESBL-KP) associated with blood stream infections (BSIs).Methods: Bacteria isolation and identification were carried out using basic bacteriological and biochemical techniques. Antimicrobial susceptibility test was performed according to the guidelines of the Clinical Laboratory Standard Institute (CLSI). Vitek 2 Compact automated system was used toconfirm the identifications (ID) and antimicrobial susceptibility test (AST). The ESBL produced by E. coli and K. pneumoniae isolates were phenotypically characterised using Modified Double Disc Synergy Test (MDDST), as recommended by CLSI.Results: All (100 %) isolates were sensitive to imipenem and meropenem, while susceptibility to other antibiotics varied. ESBL genotypes, viz, blaTEM, blaSHV and blaCTX were encountered in the BSIs. For ESBL-EC, TEM, SHV and CTX producers accounted for 33, 16.67 and 58.3 %, respectively, while 75, 91.7 and 100 % of ESBL-KP were TEM, SHV and CTX producers, respectively. In ESBL-KP, 67 % coexisted with all three genotypes (blaTEM, blaSHV, and blaCTX, while 8.3 % of ESBL-EC coexisted with the three encoding genes (CTX, SHV and TEM).Conclusion: ESBL E. coli and K. pneumoniae associated with BSI have been identified as TEM, SHV and CXT producers, with more ESBL-KP coexisting with all three than ESBL-EC.
 Keywords: β-Lactamases, Genes, Klebsiella pneumoniae, Escherichia coli
Highlights
Treatable bacterial infections are not considered as leading causes of death in patients
In terms of molecular analysis, the present findings show that cefotaximase (CTX-M), temoneira (TEM) and sulfhydryl variable (SHV) were associated with extended-spectrum beta-lactamase (ESBL)-KP and EBLS-EC blood stream infections (BSIs)
Scheuerman et al [24] reported that CTX-M was the most prevalent ESBL subtype identified in their study, while among the four classes of ESBLs, the A class TEM and SHV variants were the most-produced by Klebsiella species and E. coli
Summary
Treatable bacterial infections are not considered as leading causes of death in patients. There is a global increase in the emergence of extended-spectrum beta-lactamase (ESBL)producing Enterobacteriaceae which constitutes a high risk in healthcare-associated infections, including blood stream infections. This is of high significance due the role of ESBL producers as leading factors in morbidity and mortality. Beta-lactam antibiotics are placed amongst the safest and most frequently prescribed antibacterial drugs worldwide [13] This has led to persistent bacterial exposure to β-lactams, and subsequent mutations in the TEM, SHV, CTX-M genes of Escherichia coli and Klebsiella pneumoniae, the main ESBL producers [14,15]. The present investigation studied the bacterial isolates associated with blood stream infections, their antimicrobial susceptibilities, and ESBL production of clinical isolates of Escherichia coli and Klebsiella species associated with blood infections
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
