Trichuris suis ova (porcine whipworm eggs) as treatment for autism
Autism spectrum disorders are characterized by impairments in three core domains: social interaction, communication and restricted or repetitive behaviors. These impairments are frequently accompanied by disruptive behaviors, such as marked irritability, aggression, self-injury, impulsivity and temper tantrums. There is no treatment for the core symptoms, and only one class of medication — atypical antipsychotics — is approved by the U.S. Food and Drug Administration for treating these disruptive behaviors.
There is evidence for activation of pro-inflammatory processes and a positive family history of autoimmune illness in people with autism spectrum disorders. Therefore, a hygiene hypothesis has emerged for both autoimmune illness and autism, suggesting that in urban hygienic environments where there is a paucity of certain parasites that dampen immune activation, there is an increase in autoimmune processes.
People with autism have also been reported to improve when they have fevers. Given that fever is an immune-inflammatory response, Eric Hollander and his colleagues are investigating the use of immunomodulatory treatments such as Trichuris suis ova (TSO), or porcine whipworm eggs, for treating symptoms of autism. TSO has been shown to be effective in autoimmune disorders such as Crohn’s disease, ulcerative colitis and allergic rhinitis. A case series has also shown it to be effective in reducing symptoms of autism.
The researchers plan to complete a 28-week randomized crossover trial of TSO, including 12 weeks of TSO treatment, 12 weeks of placebo and a 4-week washout period. The investigators plan to compare the effects of TSO versus placebo on repetitive behaviors, aggression and irritability, and global functioning. They also plan to explore the relationship among clinical features, immune mechanisms and treatment response.
Work with immunomodulatory treatments such as TSO may be one way to test both the hygiene hypothesis as well as the fever hypothesis, and to develop alternative treatments for core and associated symptoms of autism spectrum disorders.
(Image credit: Wikimedia Commons)
