The degranulation process in a Mast cell. 1 = antigen; 2 = IgE; 3 = FcεRI; 4 = preformed mediators (histamine, proteases, chemokines, heparin); 5 = granules; 6 - Mast cell; 7 - newly formed mediators leukotrienes, platelet-activating factor)
Some of the most popular posts on my blog refer to my investigation into the role of histamine in autism. The investigation was productive and lead to a highly effective treatment for the wild summertime flare-ups in autistic behaviour exhibited by Monty, aged 10 with ASD.
Since I have found a therapy it is only reasonable to give the condition a name.
Seasonal Autistic Mastocytosis (SAM)
Seasonal Autistic Mastocytosis (SAM), sometimes known as Airborne Autistic Mastocytosis, occurs when airborne allergens like pollen, cause mast cells in the eyes, nose, mouth and lungs to degranulate. These mast cells contain many granules, themselves containing histamine, serotonin and heparin, a naturally occurring anticoagulant. This mast cell activation also releases inflammatory cytokines, leukotrienes and platelet activating factor (PAF). Some of these pro-inflammatory agents enter the brain and stoke up the ever-present neuro-inflammation, starting a downward spiral with further localized cytokine release. In behavioural terms, the result is that all the earlier bad behaviours will return, but in a magnified form. The observer may notice swings to aggression and self-injurious behaviour (SIB). If the subject is verbal, he may complain of unpleasant itching on arms and legs, typical of mastocytosis. The autistic subject, not understanding the reason for the itching, is likely to react with some form of tantrum, aggression or hitting that part of his body.
SAM should be considered even when only very minor symptoms of an allergy are visible, like red eyes or runny nose.
The most effective therapy is to use mast cell stabilizers, but even a standard OTC H1 antihistamine will provide some relief within 20 minutes. The dosage required to have an effect, may be much higher than the recommended dose for allergic rhinitis (hay fever), but should still be within safe limits.
An alternative therapy is simply to move to somewhere that is pollen free, even just for a weekend and observe the effect.
Depending on where you live, SAM may be possible for about 5 months of the year.
Mast cells are particularly present in the digestive tract, the lungs, skin, eyes, mouth and nose. They undoubtedly also play a major role is asthma.
Mastocytic enterocolitis is a related condition. This condition is acknowledged in the medical community. I am not a gastroenterologist, but I think Messrs Wakefield and Krigsman may have really stumbled upon cases of Mastocytic enterocolitis, when they came up with their diagnosis of Autistic enterocolitis. Incidentally, Krigsman recently published an interesting paper on genes and colitis in ASD.
Some of the frequently reported cases of GI problems in autism may also be caused by mast cell degranulation. Some of the DAN doctors treat GI problems with mast cell stabilizers and allergists routinely prescribe them.
Note on Serotonin
Approximately 30% of people with autism have high blood serotonin; perhaps a contributing factor is serotonin released by the degranulation of mast cells. We have already seen that there often appears to be central hypo-function of serotonin in autism (i.e. low brain serotonin). The endocrine system functions using feedback loops, so high blood serotonin sends a signal to lower serotonin; thus you could get low brain serotonin but high blood serotonin. Remember that serotonin does not cross the blood brain barrier.