Deciphering the Risk Factors of Autism: Are We There Yet?

Abstract

Background: Autism represents a group of developmental disorder that pose a major challenge to world-wide societies and healthcare providers with limited diagnostics and medical cure. It is widely been considered as a mental disorder characterized by speech deficit and repetitive behavior. The presumed etiology of autism involves genetic, immunologic, intestinal and synaptic irregularities, aside from environmental toxicities. Yet, the prospective factor that triggers or predominates autism remains barely understood. Objective: Herein we aim to review the literature to identify the risk factors associated with the development of autism and the need to investigate the underlying pathological events. Results: Genetic factors have been widely investigated in autism for its role in inflammation, neuronal function, metabolism and detoxification. It’s assumed to be negatively impacted by heavy metals, allergens, infectious agents and environmental pollutants. Considering the fact that, these elements individually does not make up autism, one would expect a complex interplay of neuro inflammatory and gastrointestinal system in the pathophysiology of the disease. Gut-brain axis may serve as a potential pathological link representing the plethora of mechanistic events involved in the development of autism. Abnormal activation of mast and neuro glial cells may lead to deregulated expression of cytokines and neuroactive compounds, which may disrupt the blood brain barrier permeability leading to inflammation. Alternatively it may also interfere with intestinal permeability, gut physiology, microbial composition and related metabolites. Conclusion: A glance through the literature indicates the likelihood of genetic variations and environmental factors in triggering a cascade of inflammatory events leading to the development of autism.