blocking antibodeis

my son was born with hypothyroid and diagnosed at birth,hes been taking synthroid since hes been a week old and hes always had a high tsh level,after 21 months they tell me he has a blocking antibodie and they are not able to get the correct results to his tsh levels because of this ,they told me he may not even have hypothyroid,but has to continue on his medication until the age of 3 to be safe,my son is severly delayed can these antibodies have anything to do with the developmental delay of my son,his endocrine says this is a rare case and dosent seem to know much about it.

[Deanna L Aftab Guy, MD]

there are some kids who have thyroid hormone resistance and this is more than likely what is going on, however those children have higher free T4 and tsh that is not going down in response to that. Be sure you are with a peds endo and sit down with them to understand, do not fret as much about the labs as you need to work with your peds endo in regards to the overall clinical response, is he growing, gaining weight and what is the free T4 level-which is the hormone that helps our body overall, the tsh not coming down may mean that either the pituitary is resistant or that he needs higher dose or that he is metabolizing his thyroid or as you mentioned unusual and interesting blocking antibodies. Very rare and important still to follow. He more than likely does not have developmental delay just from blocking antibodies, be sure that you are with a genetics specialist as well.

[ttatina]

my son had a special blood test done to check his tsh levels with hana treatment,his endocrine doctor thought the blocking antibodies was the reason his tsh levels are always high,but after doing this test the tsh came out to still be the same,his tsh levels are always in a range from 15 to 20 and his t4 is 12.6 .do you have any suggestions on what should be done next,his endocrine dosent seem to know what else to try,he dosent want to up his synthroid, he is taking .25 mcg and he takes a pill and a half everday, due to his jitterness and lack of sleeping when hes taking it,can having a high tsh level cause developmental delays,it seems like my doctor is giving up cause he dosent know what else to do,how important is it to get these levels down,his endocrine just tells me see u in three months and if i come up with any  suggestions i will give u a call,also do you know of any good endocrine doctors in calif. thank you