Ejikeugwu Chika, Esimone Charles, Iroha Ifeanyichukwu,Ugwu Chigozie, Ezeador Chika, Duru Carissa and Adikwu Michael
Pseudomonas aeruginosa is an important human pathogen which causes a variety of infections and often difficult to treat due to its resistance to many antibiotics including the beta-lactams. The organism is notorious for being intrinsically resistant to many antimicrobial agents by exhibiting low permeability of its outer membrane, the constitutive expression of various efflux pumps and the naturally occurring chromosomal AmpC β lactamase. The organism can also acquire additional resistant genes from other resistant pathogens via genetic transfer mechanisms. This presumptive study evaluated the occurrence of P. aeruginosa-producing AmpC beta-lactamase enzymes from an abattoir in Abakaliki metropolis, Ebonyi State, Nigeria. A total of 75 feacal swab samples from the anal region of cows were bacteriologically analyzed for the isolation of P. aeruginosa isolates using cetrimide selective agar. AmpC enzyme production was phenotypically detected by the disk approximation/three-dimensional method using cefoxitin disk (30 μg), ceftazidime (30 μg) and cefotaxime disk (30 μg). A total of 25 P. aeruginosa isolates were bacteriologically isolated from the anal swab samples. And the P. aeruginosa isolates were highly resistant to ceftriaxone, ceftazidime, cefoxitin, gentamicin, ampicillin, sulphamethoxazole-trimethoprim and cefepime. Ertapenem, nitrofurantoin and aztreonam exhibited antimicrobial activity against the P. aeruginosa isolates. A total of 9 (36 %) P. aeruginosa isolates were phenotypically confirmed to produce AmpC beta-lactamase by the disk approximation method. This study further gives impetus to the potential reservoir of antibiotic resistant bacteria in livestock. P. aeruginosa producing AmpC betalactamases in the community portends danger for the healthcare sector because such pathogens could spread to the hospital environment via community-acquired infections when patients report to the hospital for medical attention and become hospitalized. It is therefore vital to control and restrict the usage of antibiotics in the community especially in the rearing of livestock and breeding of poultry birds in order to abate the emergence and spread of drug resistant bacteria in the community.
