My son was diagnosed with type 1 three years ago at the age of five. About a year ago, his yearly blood work showed very high thyroid antibodies. I can’t remember the name of the test, but the value was supposed to be under.1 and his was 190. Lately, he has been tired and complaining of frequent headaches. His latest thyroid panel showed a TSH of 5.96, a T4 of 7.0, and a T3 uptake of 38%. Would this be a true hypothyroid or would you think that he is still in the so-called gray area? Could these values have anything to do with his fatigue and headaches? I keep hearing different views.

Your son’s TSH is slightly high and his T4 is normal so this is technically compensated hypothyroidism, but very mild. It is unlikely to be causing his symptoms. If the antibody tests were positive, then the underlying problem is called Hashimoto’s thyroiditis. Over time, he has a greater chance of becoming more hypothyroid, occasionally, also hyperthyroid. We usually screen for antibodies and T4 and TSH annually, more frequently with any questionable symptoms and/or thyroid enlargement (goiter). A positive family history of thyroid, adrenal, celiac and other autoimmune disorders also increases the risks since these are all potentiated by the same genetic factors. If the TSH stays abnormal over three to six months, even with normal T4 levels, many endocrinologists, including myself, would then suggest treatment with Synthroid to try to completely normalize all these values and thus avoid any growth or other subtle abnormalities with re-testing at about age 18 to 20 for a more definitive diagnosis. Some would just watch with repetitive samples and see if there is a trend of TSH rising and/or T4 falling before staring replacement treatment.

There are some reports of subtle heart, brain, bone, reproductive and lipid abnormalities associated with such compensated hypothyroidism, but mostly in adults, so “exactly” what course should be followed and when treatment started is not totally known. Go back and discuss this with your physicians.

SB