DETECTION OF RESISTANCE GENES IN GRAM NEGATIVE BACTERIA ISOLATED FROM STOOL SAMPLES OF ENTERIC FEVER PATIENTS ATTENDING GENERAL HOSPITAL MINNA, NIGERIA

Abstract

Infections caused by resistant gram-negative bacteria are becoming increasingly prevalent and now constitute a serious threat to public health worldwide. They are difficult to treat and are associated with high morbidity and mortality rates. This study was carried out to identify the antibiotic resistance genes in gram negative bacteria isolated from stool samples of patient attending General Hospital Minna, Niger State, Nigeria. A total of 100 stool samples were collected from the Stool Microscopy, Culture and Sensitivity Unit, General Hospital Minna, Niger State, Nigeria. The stool samples were processed for the isolation of bacteria using standard procedure. Antibiotic susceptibility profile of the isolated bacteria was determined using the disc diffusion method. The bacteria isolated from stool samples were Salmonella sp. 6 (7.4%), Shigella sp. 7 (8.8%), Escherichia coli 48 (60.0%), Klebsiella sp. 3 (3.8%), Proteus sp. 8 (10.0%) and Enterobacter sp. 8 (10.0%). Enterobacter asburiae (100%) was resistant to Ciprofloxacin, Ceporex, Fosfomycin, Sulphamethoxazole-trimethoprim and Amoxicillin clavulanic acid. Salmonella sp. (≥60%) was resistant to Sulphamethoxazole-trimethoprim, Amoxicillin clavulanic acid, Ceporex and Colistin. Proteus mirabilis (71.4%) was resistant to Amoxicillin clavulanic acid, Colistin and Penicillin. While Shigella sp. (25, 50 and 87.5%) was resistant to Ceporex, Amoxicillin clavulanic acid and Colistin respectively. Multidrug resistance was observed with the mean multiple antibiotic resistance (MAR) index of 0.5. Molecular detection of the antibiotic resistance genes showed that three of the isolates had FosA gene, while only two possessed aac3(ii) and aac(iv) gene, FosA3, FosC2, mcr1 and mcr2 were not detected in all the three isolates. The results suggest that most of the isolates were resistant to Amoxicillin clavulanic acid and Colistin. The most often observed resistance gene was FosA. These finding indicate the significance of monitoring antibiotic resistance genes.