Intestinal Microbacteria and Behaviour

The Autism Enigma aired on ABC last night and is a must watch for health care providers and parents.  It raises the possibility of the relationship between intestinal flora and behaviour, specifically focused on autism.  As the mother of a child who's behaviour is dramatically affected by his diet this episode had strong resonance.  The link was made between extended anti biotic dosage in very young children and the development of a healthy intestinal flora before the age of three.  They followed three cases of children who had developed regressive autism after being prescribed antibiotics for longer than ten days.  They showed tests which simulated the arched back and anti-social behaviour seen in regressive autism by injecting proprionic acid.  It also showed that this behaviour wore off after about thirty minutes.

"..a certain sub-population of bacteria in the gut, including the ones that have been found in patients with regressive autism, produces a fermentation or waste product, a seemingly simple series of molecules called short chain fatty acids.  This is akin to when you put sugar on yeast you get alcohol.  When you put carbs or sugars on these particular bacteria they produce a compound that, in some ways is like alcohol, because it’s a small molecule, it can easily go through the blood stream and get to the brain.  But it’s also slightly different.  And this compound called proprionic acid, for such a simple molecule, when we looked more and more into the literature, we were amazed at the kind of things that it did in terms of cell development and metabolism, cell-cell interaction, brain development, and to brain fat metabolism. PPA is one of a panel of short chain fatty acids that are produced by gut bacteria when they ferment carbohydrates from our diet.  They make proprionic acid, PPA, they also make butyric acid and they also make acetic acid.  But we’re interested in PPA because it seemed to have most of the effects that seem to relate to autism." Dr Derrick McFabe

I wonder how much this microbacteria and the effect on the brain plays a role in my own child's life with his salicylate intolerance.  My son has always had problems with his intestines since being checked into the NICU and given a ridiculously high dose of formula, despite my specifying he was a breast fed baby and to call me up any time from that point I was by his side every moment to the detriment of sleep and my bladder, and antibiotics given at this point he has done fewer solid poos than I have fingers to count them on, he is four.  I feel lucky that all the times I have been given antibiotics scripts to fill and left them in favour of allowing his own immune system to have a go.  If there is the chance of a link and this evidence is compelling, then doctors need to stop routinely prescribing antibiotics to very young children and use them as a last resort.

"The Autism Enigma" follows the work of an international group of scientists researching the human intestine and the clues their work might hold for treating and perhaps preventing this baffling disorder.  - Four Corners

The program can also be seen on ABC News 24 on Saturday at 8.00pm, on ABC iview and at abc.net.au/4corners.