ANTIBIOGRAM OF ESBL-PRODUCING PSEUDOMONAS AERUGINOSA ISOLATES OF NOSOCOMIAL ORIGIN

Ejikeugwu Chika*, Iroha Ifeanyichukwu, Orji Jerry, Ugwu Malachy, Okonkwo Eucharia, Ikegbunam Moses, Ugbo Emmanuel, Moses Ikechukwu,
Nwakaeze Emmanuel

ABSTRACT

The emergence of newer beta-lactamases such as extended spectrum beta-lactamases (ESBLs) is an important mechanism by which pathogenic bacteria develop resistance to some commonly available drugs; and this trend is of global concern due to the multidrug resistant nature of such microbes. ESBLs are plasmid-mediated beta- lactamases capable of hydrolyzing oxyimino 3rd-generation cephalosporins and monobactams but are yet inhibited by clavulanic acid (a beta-lactamase inhibitor). Fifty (50) clinical isolates of Pseudomonas aeruginosa was tested phenotypically by the double disk synergy test (DDST) method for ESBL production. Only 11 P. aeruginosa isolates (22 %) produced ESBLs phenotypically. The ESBL-producing P. aeruginosa isolates in this study were completely resistant to sulphamethoxazole-trimethoprim (100 %). Higher levels of resistance amongst the ESBL-positive P. aeruginosa were also recorded for ceftazidime (90.1 %), cefotaxime (90.1 %), gentamicin (72.7 %), ciprofloxacin (54.5) and ofloxacin (81.8 %). Nonetheless, the ESBL-positive P. aeruginosa isolates were highly susceptible to imipenem and meropenem which are both carbapenems; and are the drug of choice for treating infections caused by ESBL-positive bacteria. The high level of resistance of ESBL-positive bacteria to some commonly available antibiotics (as obtainable in this study) gibes impetus to the antibiotic degrading capability of microbes expressing this enzyme. It is critical for hospitals (especially in this part of the globe) to always be on the lookout for multidrug resistant pathogens inclusive of those expressing ESBLs in order to contain any outbreak due to them.

Keywords: Pseudomonas aeruginosa, ESBLs, Nosocomial, Antibiogram.