Abstract: Background: Autism children were reported to have gastrointestinal problems that are more frequent and
more severe than in children from the general population. Although many studies demonstrate that GI symptoms are
common in autism, the exact percentage suffering from gastrointestinal (GI) problems is not well known, but there is
a general consensus that GI problems are common in autism. The observation that antifungal medications improve
the behavior of autism children, encourage us to investigate their intestinal colonization with yeasts. Aim of the
work: The purpose of this work was to investigate the intestinal colonization with yeasts in autistic patients and to
assess the role of yeast as a risk factor to cause autism behavior. Patients and methods: The study included 83
cases diagnosed as autistic children referred from the neuro-pediatric clinic and 25 normal children as a control
group. All children under the study came to Phoniatric clinic, during the period from 2010 to 2012, complaining of
delayed language development with autistic features. Children in this study were classified into 2 groups; control
and study groups. All children were subjected to interview, E.N.T examination, language assessment, Childhood
Autistic Rating Score (CARS), stool culture for Candida albicans, complete audiological and psychometric
evaluation. Results: There was significant relation between the autistic children and heavy growth of Candida
albicans in stool culture. Conclusion: The high rate of Candida albicans intestinal infection in autistic children
may be a part of syndrome related to immune system disorders in these patients.