Multiple-antibiotic resistance pattern of Coliform bacteria isolated from different sources in Iwo, Nigeria

Abstract

Antibiotic resistance has become a big public health concern. Experiments were carried out to assess the antibiotic resistance pattern in coliform bacteria isolated from different sources in Iwo, Nigeria. Coliform bacteria were isolated on nutrient and xylose lysine deoxycholate (XLD) agar media and identified using standard procedures. Antibiotic multidisc containing ceftazidime (30µg), cefuroxime (30µg), gentamicin (10µg), ciprofloxacin (5µg), ofloxacin (5µg), augmentin (30µg), nitrofurantoin (300µg), and ampicillin (10µg) were used to study the resistance patterns of the isolates. Statistical analyses were carried out using the analysis of variance test (ANOVA) and the PAST (paleontology statistics) software analytical package where applicable. Twenty-five (25) Coliform bacteria consisting of four genera were isolated and identified. Enterobacter had the highest occurrence (44%) followed by Klebsiella (24%), E. coli (20%) while Citrobacter had the lowest occurrence (12%). Overall more Coliform isolates were recovered at the abattoir (8), cafeteria (6), poultry (5), cow ranch (4) and hostel sewage (2). The highest resistance observed by the isolates was to ampicillin (91%) followed by augmentin (55%), while many of the isolates were sensitive to ceftazidime, gentamicin, ofloxacin and ciprofloxacin. Polymerase chain reaction (PCR for 16S RNA) method was carried out to screen for CTX-M gene in beta-lactam-resistant isolates. A number of organisms have developed multiple resistances to several antibiotics and of major concern are Coliforms in which new resistance characteristics have been discovered leading to increased resistance to drug therapies. This may become a great public health concern if not curbed.