Carbapenem Susceptibility Pattern among Pseudomonas aeruginosa isolates from clinical specimens in South Eastern Nigeria

Akujobi CN, *Ezeanya CC, Madu OJ, Egwuatu CC.

Affiliation:- Department of Medical Microbiology and Parasitology, Faculty of Medicine, Nnamdi Azikiwe University, Nnewi Campus, Nigeria.

Author’s contributions- All the authors contributed equally to this paper.

*Correspondence to:- Ezeanya CC. Department of Medical Microbiology and Parasitology, Faculty of Medicine, Nnamdi Azikiwe University, Nnewi Campus, Nigeria.

Abstract:

Background: Carbapenems are a class of ? lactam antibiotics with broad antibacterial activity. However, the increasing use of the drug class has resulted in varied susceptibility pattern of Pseudomonas aeruginosa thus limiting treatment options. Aims: The study was done to determine the carbapenem susceptibility pattern and to detect novel class 1 integron of the metallo-beta-lactamase genes among Pseudomonas aeruginosa isolates from clinical specimens in South Eastern Nigeria. Settings and Duration of Study: The study was carried out in South Eastern Nigeria with all experimental works done in Nnamdi Azikiwe University Teaching Hospital, Nigeria from June 2012 – January 2013. Methods and Materials: Five hundred clinical specimens were examined of which 36 P.aeruginosa was isolated here in South Eastern Nigeria. Antimicrobial susceptibility pattern of the isolates to Carbapenem was determined by disc diffusion method. PCR analysis involved: DNA Extraction, amplification of beta-lactamase genes. Result: Meropenem had highest susceptibility of 36 (100%), Imipenem 27 (75.0%) and Ertapenem 4 (11.1%). The PCR results showed that twenty-one isolates were resistance to ?-lactamase encoding resistance to carbapenems but do not harbor a novel class 1 integron (CS) of the metallo-?-lactamase (MBL) blaIMP-1 gene. Conclusion: Carbapenems are one of the antibiotics of last resort for many bacterial infections. Recently, alarm has been raised over the spread of drug resistance to carbapenem antibiotics among this organism. There are currently no new antibiotics to combat bacteria resistance to carbapenems, and worldwide spread of the resistance gene is considered a potential nightmare scenario.

Key words: Carbapenem susceptibility; Pseudomonas aeruginosa isolates; Clinical specimens; Class 1 integron.