Antibiotic Susceptibility Profile and Prevalence of AmpC among Clinical Bacterial Isolates obtained From Northwestern Nigeria

Antibiotic Resistance is spreading all over the world conferring multiple resistant in the treatment and management of life-threatening infections. Cephalosporins are antibiotics prescribed daily for a wide variety of infections in Nigerian hospitals. The production of bla-AmpC enzymes by many Enterobacteriaceae conferred resistance to such class of antibiotics. The aim of the study is to determine the antibiotic susceptibility and prevalence of AmpC among clinical bacterial isolates obtained from Northwestern Nigeria. A total of 1000 clinical bacterial isolates were collected from seven states of northwestern Nigeria and were screened phenotypically for AmpC production using the Disk Approximation test. Antibiotic sensitivity test was performed according to clinical and laboratory standard Institutes guidelines (CLSI). Acinetobacter baumanii, Serratia liquefaciens and Providencia sp showed 100% resistance to third-generation cephalosporin antibiotics as well as Levofloxacin, Impinem, and Tigecycline, moderate susceptibility was observed with Colistin, followed by Proteus mirabilis (85%) resistance to Ceftizoxime. Tigecycline and Colistin were the most active drugs against the isolates. The prevalence of AmpC production among the isolates showed that Acinetobacter baumanii, Aeromonas sp., Providencia sp., Serratia liquefaciens and Citrobacter freundii had the highest prevalence of 100% each. Enterobacter cloacae had the least value of 50%. Similarly, high Multi-Drug Resistance (MDR) 100% was shown by A. baumannii, Aeromonas sp, Providencia sp, and S. liquefaciens with least values from Staphylococcus aureus (33.1%). The occurrence of AmpC was higher among male patients with a prevalence rate of 54.1%, p-value >0.001. The occurrence of these resistance-conferring enzymes was chronologically sensitive as its prevalence is more pronounced among patients aged >60 years (64.5%) with the least value among patients aged 21-30 years (23.1%), (p-value >0.001). The trend in the prevalence of AmpC production and MDR resistance among the states of Northwestern Nigeria is in the following order: Sokoto > Kaduna > Katsina > Kebbi > Kano > Jigawa > Zamfara. The results from this study implied that AmpC production is on the increase in Northwestern Nigeria and that the spread of these resistance-conferring enzymes among bacterial isolates is an issue of public health concern. Therefore, proper monitoring and surveillance for proper prevention and infection control may limit the further spread of these isolates.