Isolation and characterization of enteroaggregative Escherichia coli among the causes of bacterial diarrhea in children


Diarrhea is a public health problem and an important cause of morbidity and mortality, enteroaggregative Escherichia coli (EAEC) have been recognized increasingly as agents of diarrhea in developing and in industrial countries. So the aim of this study is to study the prevalence of EAEC, its virulence factors and study it´s resistance to antibiotics. Results showed that E. coli represent 86 (32.9%) of the isolated bacteria. the high percentage 60% were EAEC, plasmid-encoded toxin (pet) was the marker most prevalent detected 14/30(28%) than EAST1(for EaggEC heat-stable enterotoxin 1)which detected in 9/30(18%) of EAEC and two virulence genes (pet+ and EAST1+) were found in7/30(14 %) of EAEC. 10% of isolates were contained capsule but only 3.3%isolates of E. coli have Type Ι pili while all the isolates possess Type ΙΙΙ pili. The results in the present study indicated that all E. coli were negative to Congo red dye agar test in contrast high percent of E. coli isolates were able to produce biofilm (86.7%) with different degree of thickness, while 20%isolates were urease positive after 24- 48 hrs, and 10% isolates were able to produce amylase. All isolates of E. coli were unable to produce Lecithinase, nuclease and hemolysin. While, 93.3% of E. coli isolates produced β-lactamase. The frequency of Sorbitol E. coli fermenter was 66.7%. In this study EAEC isolates were resistance (100%) to Penicillin and Ampicillin, High resistance(96.7%) was observed to each of Ceftriaxone, Cefotaxime and Trimethoprim. and Tetracycline (76.7%), resistance percentage of Both Amikacin and Rifampicin were (40%) and (33.3%) respectively. Higher sensitivity was reported to Gentamicin (63.3%), Ciprofloxacin(60%) then Nitrofurantoin (56.7%). The data from this study draw attention to the importance of notifying diarrheal disease. The high level of antimicrobial resistance observed in our study raises a broader discussion about the indiscriminate use or misuse of antibiotics and the risks of empirical antibiotic therapy in children of a very young age.