There is a health condition recognized in the biomedical field for autism and related disorders called PANDAS (Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal infections). This is a condition caused by an immune reaction triggered by the presence of Group A Beta-Hemolytic Streptococcal infection. Various strep bacteria produce toxins as part of their infectious nature.
The immune system responds in an attempt to neutralize and eradicate the toxins. However, this immune-toxin (aka: antibody-antigen complex) reaction creates immune complexes which are deposited in various tissues of the body. If these immune complexes land in the kidneys there is an immune reaction called post-streptococcal glomerulonephritis, in the heart it is called rheumatic fever, and in the brain PANDAS can ensue.
This autoimmune reaction (self-directed immune reaction to body tissue) in PANDAS is directed to the Basal Ganglia area in the brain. This area has been associated with disorders such as obsessive-compulsiveness (OCD), strange body posturing/movements called chorea, and the typical TIC movements (quick jerking or vocal tics) associated with Tourette's Syndrome. With obsessive-compulsive behavior anxiety is usually a major problem.
Some individuals on the autism-spectrum suffer with extreme anxiety, but without obsessive-compulsive behavior, while in others the OCD is severe. Even though PANDAS remains a controversial topic in medicine it is reported that PANDAS can cause or exacerbate Tics, Tourettes, and Obsessive-Compulsive Disorder. Approximately, 25% of individuals who have one or more of these conditions have what appears to be PANDAS.
Unfortunately, treatment options are limited, although certain biomedical autism treatments such as low dose naltrexone, dietary intervention such as the gluten and casein-free diet, and various supplements that support normal immune function such as Transfer Factor can be helpful in reducing the overall reactivity of the immune system, PANDAS remains a difficult thing to treat.
Some individuals respond quite well to antibiotics. I have seen in cases where a short course of antibiotics, such as 10 to 14 days of Keflex, Penicillin or Zithromax definitely helps, particularly with the OCD behaviors. In other situations more advanced biomedical therapies such as intravenous immunoglobulins (IVIG) are needed to short-circuit the autoimmune response. Plasmapheresis, which is a blood cleansing process performed to help diminish the immune-toxin reactions, has shown benefit for some individuals. Unfortunately, no treatment is 100% effective for everyone, and some people remain symptomatic even after medical intervention.