Higher Incidence of Enterohemorrhagic Escherichia coli (EHEC) in Autistic Children and Their Potential Role in Exacerbation of Autistic Enterocolitis

Abstract

Based on the hypothesis that abnormal pathogens in the bowel can affect the brain and consequently can play a major role in the exacerbation of autistic symptoms, we have been in an attempt to detect and identify intimin gene producing microorganism Escherichia coli from stools of autistic children using culture-independent techniques. The presence of intimin gene was detected using polymerase chain reaction (PCR) with specific primers. Sequence of the gene amplified after PCR matched to the sequence of intimin gene with 100% accuracy. EHEC strains are found to produce strong cytotoxins, the important virulence attribute of EHEC being the intimin protein encoded by eaeA gene. Hitherto deemphasized and played down its role in autistic children, the intimin gene was found in a significant number in the stools of children with autism compared to normal children. Our results,thus, show a high degree of prevalence of eaeA positive E. Coli in children with autism. A relevant question is if this greater prevalence of EHEC can be causative to the digestion problems observed in autism which may further affect brain and cognitive functions. In order to understand the role of intimin as a prospective candidate leading to cognitive dysfunctions, we had an in silico study on the effects of intimin on selected neurotransmitters which also showed a profound significance with all the docked conformations giving negative binding energy in the order serotonin, dopamine and acetyl choline.