Identification and antibiotic sensitivity test of bacteria from stools of patients with acute diarrhoea

Abstract

One hundred and fifty stool samples from 65 female and 85 male patients with acute diarrhoea from the Central Hospital, Agbor (Nigeria) were examined to ascertain the likelihood of cholera outbreak in Agbor. The samples were preserved in Carey-Blair semi-solid medium, inoculated directly on blood agar, McConkey agar, deoxych-olate citrate (DCA) agar and thiosulphate-citrate-bile-salt (TCBS) agar, and incubated aerobically for 24 h at 37 º C. The isolates were characterised by sugar fermentation tests and cultural morphology. Seven bacterial gene-ra were identified and Escherichia coli had an incidence of 58 %, Vibrio cholerae 36 %, Salmonella spp. 14.7 %, Aeromonas hydrophila 9.3 %, Shigella dysenteriae 7.3 % and Klebsiella oxytoca 7.3. % each and 3.3 % for Shigella flexneri. The V. cholerae isolates were designated VC01-VC07, and were serotyped using polyvalent, monospecific Ogawa and Inaba 01 and 0139 antisera. V. cholerae 01 biotype ETor serotype Ogawa was predo-minant and prevalent between April - May 2008, when most of the isolates were isolated. For the VC01, 39 iso-lates were from males (72.2 %) and 15 were from females (27.8 %). The bacteria isolates were tested against 9 antibiotics by the disc diffusion method. E. coli, Salmonella spp, Shigella spp and Aeromonas hydrophila were all resistant to gentamycin, tetracycline and penicillin (100 %) but were sensitive to chloramphenicol, ciproflox-acin and cefotaxime. All the V. cholerae strains (100 %) were highly sensitive to cephataxime, ciprofloxacin, chloramphenicol and erythromycin, but were resistant to streptomycin (71.4 %), tetracycline (71.4 %) and peni-cillin (57.1 %), while all isolates showed intermediate resistance or sensitivity to gentamycin. The study indica-ted that there was an ecological niche that supported V. cholerae 01 biotype in Agbor, which could become pub-lic health concern, unless detailed epidemiological investigation is conducted.