Isolation and Identification of some Aerobic Pathogens Causing Diarrhea Using Chrom agar

Abstract

Worldwide diarrheal diseases are the second leading cause of death; about 25 million enteric infections occur each year. One hundred faeces samples were collected from patients attended to Alribat, Al Raed Al Salam and Military Hospital during April to June 2012. The samples were examined macroscopically and microscopically then cultured on CHROM agar and MacConkey agar for primary isolation of some aerobic pathogens. Purification of isolates was carried out on Nutrient agar. The results revealed high percentage of mixed isolates 29 (29 %) on CHROM agar compared with MacConky agar 13 (13 %). The isolated Gram-negative bacteria were 114 (87.02%) while Gram-positive bacteria were 17 (12.97%) on CHROM agar. The isolated Gram-negative bacteria were Escherichia coli 81 (61.83%), Shigella dysenteriae 17 (12.97%), Klebsiella aerogenes 9 (6.87%), Salmonella typhi 2 (1.52%), Salmonella typhimurium 1 (.76%), Klebsiella ozanae 1 (.76%), Klebsiella oxytoca 1 (.76%), Citrobacter diversus 1 (.76%) and Proteus mirabilis 1 (.76%) while Gram-positive bacteria were Staphylococcus aureus 9 (6.87%) and Streptococcus faecalis 8 (6.10%). It was concluded that CHROM agar was a very helpful medium for primary isolation of some aerobic ‫‪pathogens from faeces specimen especially in mixed‬‬ ‫.‪infection‬‬