Autism is one of the developmental disorders of brain function, as in the others, there are several causes. In most cases, the cause is unknown . There may be an inherited susceptibility to some environmentally determined stress. In few cases, there is evidence of tuberous sclerosis, hypomelanosis of Ito, fragile X, phenylketonuria,, congenital rubella, neonatal herpes simplex, hydrocephalus, malformation or other static encephalopathy Perinatal brain injury does not cause autism as an isolated deficit. He cites case reports in which insults to the brain were followed by onset of infantile autism.
Autism can occur or be closely simulated in children with known organic brain damage.
Other etiologic factors include complications at birth, prenatal damage, infectious diseases, encephalitis. Symptomatologically equivalent cases of autism can be caused by cerebral-organic damage. He explains that it is now well accepted that autism results from dysfunction in certain parts of the central nervous system that affect language, cognitive and intellectual development, and the ability to relate. If in a proceeding on a petition it is shown by a preponderance of the evidence then an encephalopathy was caused by infection, toxins, trauma, or metabolic disturbances the encephalopathy shall not be considered to be a conditions set forth in this table. As applied to this case, these sections require no more than a showing that there was a metabolic disturbance and that more likely than not it caused the encephalopathy the fact that respondent has not identified a specific metabolic disorder by name, therefore, in and of itself, is irrelevant.