Shirley: For about 5 years, my daughter totally refused all food and lived solely on Prosobee Baby Formula. She wouldn’t even try to chew it, wouldn’t even eat pureed. She is now 10 years old. Last year I finally found a doctor who would give her the Thyrotropin Releasing Hormone (TRH) test. We found out she was severely hypothyroid. She tested normal on all the regular thyroid tests, but the TRH proved they were totally incorrect. Since she has been on the thyroid medication she has started to eat and now has a huge appetite. For years she was 43 lbs. She is now about 70 lbs. She still wants some food pureed, but now she has also started eating quite a few table foods too. Her holistic doctor thinks that her thyroid was so swollen that it caused a stricture of the esophagus. That’s why she refused to eat, was so gaggy and projectile vomited all the time. She was diagnosed at 18 months as PDD/Autistic Spectrum. Since this time, she has also had a funny curl (I always called it a neurological curl) to her tongue. When she opened her mouth to take a bite, her tongue would elevate in the back on one side and this would cause her tongue to curl sideways. So it was hard for food to go on her tongue rather than under it. This too is probably caused from atrophy to the muscle due to the hypothyroidism. My guess is that she has probably suffered needlessly for the past 7 years with a severe thyroid problem. No doctor ever diagnosed it properly due to the inaccuracy of the fast paced testing. Only the TRH test showed the real problem.
P.S. My daughter was also completely nonverbal for 7 years. After addressing the thyroid problem, she started talking and can now talk in 8, 10 and 15 word sentences.
Polly: I’ve talked to several people who found that thyroid supplements were beneficial for their autistic children. However, it will be a while before enough parents try this and we get an idea of what percentage it helps. I think we are back to the same problem with the blood tests. They measure how much thyroid is in the blood, but not how much is being used. These blood tests are notoriously inadequate for children. The TRH test has recently come to people’s attention because it has uncovered many cases of hypothyroidism when the standard TSH, T4, and T3 tests didn’t reveal the problem. Here is a site that speaks of another autistic child who was diagnosed with hypothyroidism by the TRH test, http://www.avn.org.au/newpage118.htm. The normal thyroid tests didn’t reveal a problem. However, I don’t trust even the TRH test to reveal all cases of hypothyroidism, and I don’t think it is a particularly safe test. You need a doctor who will make a skilled interpretation of symptoms instead of relying only on tests. Instead of risking regression with this TRH test, a therapeutic trial of thyroid would be a much more civilized approach.
If we but look for it, there are probably plenty of reasons why an autistic child might need thyroid despite normal TSH, T4, and T3. Here are a few items that suggest these tests might be inadequate when autism is present. They need to be more fully investigated in autism.
1) Serotonin or its influence is often high in the autistic. Serotonin suppresses the release of TRH, which in-turn lowers TSH.  A 1989 study of autistic children showed that they have a lowered TSH and lowered delta TSH response to TRH. (This is called central hypothyroidism.) In 5 of the 14 children studied, the response was borderline.  Doctors rarely perform this test, and therefore many cases of hypothyroidism in autism are perhaps being missed.
2) G-protein defects could interfere with thyroid.
3) Bilirubin might be higher than normal in autistic children. (Glucuronic acid and phenol-sulfotransferase, PST, are used to clear or get rid of bilirubin, and phenol-sulfotransferase is not working properly in most of the autistic children.) A buildup of bilirubin will give a yellowish cast to the skin, which a few of the moms have mentioned. Bilrubin is toxic to the brain. Bilirubin can inhibit the transport of thyroid into the liver (invitro).  A lack of thyroid transport into the liver is serious because the liver is the main place where thyroid is converted into the active form.
4) The gluten in grains and the casein in milk have opioid properties. If undigested, these proteins might induce some of the symptoms of autism. Since other opiates are known to interfere with TSH and/or its response to TRH, there is a possibility that these opiate like compounds do too. 
5) A buildup of mucopolysaccharides can interfere with thyroid getting to the cells. Which means the blood thyroid levels may look normal, but there is a deficiency. This buildup of mucopolysaccharides seems to occur fairly often in those with mitochondrial disease. People on the net are starting to notice a correlation between some cases of autism and mitochondrial disease. How often is there a buildup of mucopolysaccharides in autism?
6) Lipopolysaccarides from gram-negative bacteria in the gut can cause central hypothyroidism.
7) Then of course there is mercury. In chapter 7 of Hal Huggin’s book, Uninformed Consent, he speaks of mercury binding to iodine and ruining the quality of the thyroid hormone. On page 109, he states, “
A person may have adequate levels of T3 and T4, but if the hormones are contaminated, for practical purposes the person is functionally thyroid deficient.”
Karen: My daughter definitely has hypothyroidism. We see a specialist in NYC, and he diagnosed it with a TRH test. She had all the signs, including low resistance to infections and an ice-cold body. I don’t recommend this TRH test because it caused my daughter to regress. The regression stopped when we put her on thyroid hormones, but it was a frightening interim. Nearly all kids on the spectrum, according to this doctor, have hypothyroidism, along with low-functioning adrenal glands.
My daughter has been taking thyroid replacement hormones (T3/T4) for nearly a year, Hope for Autism through Nutrition The Health Forum—Book 5 36 and this has greatly improved her health. She is growing and gaining weight. My daughter’s weight before we started the hormones was hovering around 36 pounds. Now it’s about 42 pounds. We were able to wean her from Nystatin without a return of drunken giddiness. And we’re not up with her for hours every single night with coughing caused by a swollen thyroid. Now, this only happens when we need to raise her dose.
The downside is that we’ve had to raise her dose four times. She is taking a full grain, and I think it could even go higher. I am concerned because it seems like she always needs more. It’s almost like she’s resistant to the hormones. Her pre-treatment hormone levels were in the normal range and her TSH (well over 5.0) was on the very high side of normal.
We are now working with a new homeopath to try to get to the root cause of this problem. I’m keeping my fingers crossed than can reduce or eliminate the need for huge doses of hormones. Polly made a very good point about this being related to mercury poisoning. Maybe this is the root cause.
Later – Polly: Here are a few more things that hint at a possible involvement of the thyroid in autism.
1. Thyroiditis. At the recent DAN! 2000 Conference on autism, Jane El Dahr, MD, mentioned that you will often find thyroiditis in autistics if you look for it.
2. Mary Megson, MD, said that she is seeing a lot of thyroid problems and she thinks it might be because of interference with the receptor that the thyroid simulating hormone (TSH) lands on. She is also finding adrenal issues in some of these children.
3. According to Dr. Megson, night blindness is often found in the families of autistic children. I find it interesting that Dr. Wilkinson includes visual disturbances and night blindness in his list of possible hypothyroid symptoms. (See the thyroid chapter in Book 4 of this series.)
Since thyroid along with the retinol form of vitamin A is needed to create progesterone and pregnenolone, I wouldn’t be surprised to find a disturbance in the creation of these later hormones too.  In fact, after normalizing the fatty acid profile, Patricia Kane, PhD, has had some success with administrating 25 mg of pregnenolone to autistic children. 
Theoretically, serotonin’s release of stored unsaturated free fatty acids could inhibit the conversion of T4 thyroid to T3 thyroid.  This would make T3 thyroid a particularly important component of any thyroid therapy. At least, the appropriate amount of T3 thyroid needs to be explored in each person. Unfortunately, you may have to switch doctors if they insist on only using T4 thyroid.
Hypothyroidism and ADD/ADHD
Polly: It is imperative that hypothyroidism and hyperthyroidism are ruled out before resorting to Ritalin. Hypothyroidism and hyperthyroidism change the way the brain uses dopamine, norepinephrine and serotonin. In a study of people with generalized resistance to thyroid hormone, there was a very high incidence of attention deficit.  In another study of people who were bipolar, those who were also ADHD were hypothyroid.  A component of the immune system called IL-1 is suspected of disrupting memory and learning in attention deficit.  This same IL-1 can cause central hypothyroidism and IL-1 is associated with thyroiditis.  Too much thyroid can also interfere with attention. 
Excerpt from ebook, Hope for Autism through Nutrition, The Health Forum—Book 5