I have a friend whose son has PDD-nos and has had seizures just recently in his youn-adult life. I dunno if they're related or just co-incenence. Granted, both are neurologicol in origin.
Persons with autism may only prefer to eat certain foods and gettig in all the dietary requirements can be a challenge. Thus, he may be anemic or have a vitimin/mineral deficiancy.
I knew one autistic boy who would only eat speghetti, no sauce, nothing else. It was he<< to get him to try other stuff.. He did eventually eat whole wheat spagetti, then fetucinni, then gradually spinach and tomato fetucinni. Also most pasta is made with "enriched" wheat flour so some of that helped (I think).
If you mean passing out like fainting, I don't think so. There could be something else going on.