Molecular detection of virulence factors encoding genes in Escherichia coli isolated from diarrhea in children under 5 years


  • ALI Al-Hisnawi Department of biology college of sciences - Kerbala University


virulence factors, Escherichia coli, diarrhea, aEPEC, tEPEC


 The present study was carried out to investigate the bacteria that cause diarrhea in children, as well as the virulence factors possessed by Escherichia coli bacteria isolated from the stool of children under 5 years of age. with symptoms of diarrhea.  The bacterial isolates were diagnosed using the Vitek 2 technique, then 40 E. coli isolates were subjected to molecular detection by PCR, and the selection of samples was based on examining the stool sample under a light microscope, which contained pus cells or red blood cells .  The results showed that the incidence of diarrhea in males (57.5%) 46 was higher than that of females (45%) 34, and the statistical analysis showed that there was a significant difference between infected males and females (P = 0.02) . Molecular detection results showed that 20 (50%) of bacterial isolates carry genes (STX1, STX2, eae, bfpA), which belong to the pathotypes of E. coli bacteria that cause diarrhea (DEC), and that 10 (50%) are bacterial isolates   Enteropathogenic EPEC, and 10 (50%) isolates carrying two genes together (STX1 & STX2) belong to the intestinal hemorrhagic bacteria EHEC, and it was noted that there was no clear significant difference between the two strains (P > 0.05).  Bacterial isolates 8(80) carrying the gene (eae) belonging to atypical enteropathogenic bacteria   aEPEC, and two bacterial isolates (20%) carrying two genes together (eae & bfpA) belong to the typical enteropathogenic bacteria tEPEC. Statistical analysis showed that there was a significant difference between the two types of this bacteria (P = 0.05) .