Hussein Rabie Farghaly MD, Presenter: Nothing to Disclose

Khaled Elsayah MD, Abstract Co-Author: Nothing to Disclose

Asma Zahran MD, Abstract Co-Author: Nothing to Disclose

Re-evaluate children with CH to detect the cause and to find those with transient hypothyroidism that are not in need for long life L-thyroxin therapy

20 children aged 3-4 years with primary CH with no previous imaging studies were enrolled in this study. Subjects with any previous imaging studies were excluded from the study. Thyroxin therapy was discontinued for 4 weeks, at which time thyroid function tests (TFTs) and a thyroid scan using Tc-99m pertechnetate were simultaneously obtained.

There were 6 cases (30%) with thyroid agenesis in which the thyroid scan revealed no tracer accumulation at the thyroid region or any of the ectopic sites and the TFTs denoted hypothyroid state, 5 cases (25%) had sublingual thyroid ectopia in which there was only focal tracer uptake at the sublingual region with no tracer uptake seen at the thyroid region and also the TFTs were still of hypothyroid state. In four cases (20%) thyroid gland appeared in the normal site and TFTs were within the normal range. In a further 20% of cases dyshormonogenesis was detected, 3 of them showed normal site by thyroid scan with normal size, in one of these 4 cases the thyroid gland was enlarged. Hypothyroid TFTs were present in all these four cases. Only one case (5%) had Lt. hemiagenesis in which thyroid scan revealed tracer uptake in a small sized Rt. thyroid lobe with hypothyroid TFTs

Thyroid scan using Tc-99m pertechnetate combined with thyroid function tests is a valuable method for detection of the cause of CH and in finding those with transient hypothyroidism in whom TFTs were normal and thyroid was normal in site and size and they did not need life long L-thyroxin therapy. Furthermore Tc-99m pertechnetate thyroid scan can be recommended for initial investigation of suspected CH and for proper management.

Thyroid scan is simple and safe test to use in intial investigation in childern with suspected CH  helping in define the cuase of CH

Farghaly, H, Elsayah, K, Zahran, A, Re-evaluation of Primary Congenital Hypothyroidism Using Tc-99m Thyroid Scan.  Radiological Society of North America 2008 Scientific Assembly and Annual Meeting, February 18 - February 20, 2008 ,Chicago IL. http://archive.rsna.org/2008/6015676.html