Research by Dr. Sidney Finegold compared the gut flora of children with regressive ASD to neurotypical (typically developing) children.  The results show that clostridia counts were higher in the children with autism. Not only were the counts higher in those with autism, but the number of clostridia species were also higher.  Children with ASD had 9 species of Clostridium not found in the neurotypical group.  The neurotypical group showed only 3 species not found in children with autism. In all, there were 25 different clostridia species found. In stomach and small intestine specimens, the most striking finding was total absence of Clostridia from neurotypical children and significant numbers of such bacteria from children with autism.

These studies demonstrate significant alterations in the upper and lower intestinal flora of children with late-onset ASD and may provide insights into the nature of this disorder.

Research by Dr. Derrick McFabe, at the University of Western Ontario, has explored acquired Clostridia infection and it’s relation to autism spectrum disorder.  In his study, rodents injected with propionic acid (from Clostridial species) displayed autism like behaviours including:

  • Spinning
  • Repetitive behaviours
  • Seizures / convulsions
  • Pushing away
  • Hyperactivity

Clostridia’s could play a role in autism:

  • Too much clostridia alters microbiome and changes gut-brain axis
  • Impaired immune activity and activated brain immune cells that stimulate glutamate and high levels – immunoexcitotoxicity
  • Damage to digestive tract reducing function including absorption of nutrients, management of inflammation and detoxification of harmful toxicants
  • Depletion of carnitine resulting in mitochondrial impairment
  • Impairing methylation
  • Increases oxidative stress
  • Glutathione depletion – glutathione is the most important antioxidant and manages elevated levels of glutamate. Depletion increases immunoexcitotoxicity