INCIDENCE AND ANTIBIOGRAM PROFILE OF DIARRHOEAGENIC ESCHERICHIA COLI IN DIARRHOEA AND NON-DIARRHOEA CASES AMONG INHABITANTS OF ONDO STATE,NIGERIA

Abstract

Investigations were conducted to determine the incidence and antibiotic resistance profile of diarrhoeagenic Escherichia coli (DEC) in diarrhoea and non-diarrhoea cases in some patients and apparently healthy individual in Ondo state, Nigeria. In this study, a total of 550 stool samples were collected, comprising 400 samples from patients with acute diarrhea and 150 samples from apparently healthy individuals. Diarrhoeagenic E. coli (DEC) strains were isolated from the stool samples of 250 patients and characterized using conventional techniques. Antibacterial assay was accomplished using the disc diffusion methods. The genetic mediated of antibiotic resistance shown by the bacterial isolates were investigated by Polymerase chain reaction (PCR), plasmid profiling and plasmid curing using standard methods. Age group 1 – 5 years had the majority of the cases at 170 (42.5%), 15% of the cases were in the age group < 1 year. Also, age group 5 – 15 years had 90 (22.5%), 50 (13.3%) cases were in the age group 15 – 45 years while age group > 45 years had 30 (6.7%). A total of 228 (57%) males and 172 (43%) females were found to be diarrhoeic patients. In non-diarrhoeic patients, majority of the cases were found in the age group 5 – 15 years (40%), while 20 cases were in age group < 1 year, 20% cases were in the age group 1 – 5 years, age group 15 – 45 years have 13.3% and 6.7% cases were in the age group > 45 years. Diarrhoeagenic Escherichia coli were detected. The other bacterial isolates include the species of Shigella, Salmonella, Klebsiella. Proteus, Pseudomonas, Stapyloccocus, and Enterococcus. Diarrhoeagenic E. coli was completely inhibited by nitrofurantoin(100%) , amoxycillin(100%) and ofloxacin(100%) but was least inhibited by cotrimoxazole (20%) and ampicillin (5%). The species of Shigella and Salmonella were remarkably inhibited by chloramphenicol (30%), ampicillin (5%) and cotrimoxazole (5%). Pseudosomonas aeroginosa were resistant to most of the antibiotics except ampicillin (50%), ciprofloxacin (80%) and ofloxacin (80%). Polymerase Chain Reaction was used to detect the strains of diarrhoeagenic Escherichia coli isolates through their virulence genes and it was discovered that they all belong to Enteroheamorragic Escherichia coli (EHEC), Enterotoxigenic Escherichia coli (ETEC), and Enteroaggregative Escherichia coli (EAEC) strains. The plasmid analysis of diarrhoeagenic Escherichia coli revealed the presence of plasmid with estimated molecular weights of 22592bp, 56480bp and 59169bp which were presumed to have been lost during plasmid curing. The presence of these plasmids is responsible for the antibiotic resistance of the organisms but are lost after curing, making them susceptible to antibiotics. Therefore, this project has provided information on the types of diarrhoeagenic Escherichia coli strains that are responsible for diarrhoea in Ondo State and findings from this study have shown that diarrhoea is more common in children than in adults.