192 HYPERTHYROIDISM IN A BOY WITH CONGENITAL HYPOTHYROIDISM WHO HAD THYROID HORMONE REPLACEMENT THERAPY FOR 13 YEARS

• Published in: Clinical Pediatric Endocrinology Vol. 12; no. 2; p. 158
• Main Authors: Otsubo K, Mizota M, Hizukuri K, Tamada I, Arima S, Ono S, Kawano Y
• Format: Journal Article
• Language: Japanese
• Published: The Japanese Society for Pediatric Endocrinology 2003
• ISSN: 0918-5739

The patient's birth weight was 2770g, his gestation age was 40 weeks. At 16 days of age, he was referred because of abnormal thyroid hormone screening results. Serum levels of thyroid stimulating hormone(TSH) at 5 and 12 days of age were 76.76 μU/ml and 38.08 μU/ml, respectively. At 16 days of age, His serum level of TSH was 91.0 μU/ml and serum level of thyroxine(T4) was 6.9 μg/dl. He was diagnosed to be the case with congenital hypothyroidism and received hormone replacement therapy. At 18 months of age, medication was stopped for 7 days and 123I thyroid scan demonstrated a normally located thyroid grand with homogeneous up take of radio labeled iodide, the up take rate was 15% (normal range, 10- 40%) at 24 hours. Potassium thiocyanate discharge test showed 25%, he was suspected to have iodide organification defect. He showed normal growth and development with therapy. The dosage of thyroid hormone was increased as he grew to a maximum dose of 110 μg/day at age 11. Until the age of 13 his serum levels of TSH were normal. However, at 13 years old his serum level of TSH showed a level below the detectable range for the first time. The dosage of thyroid hormone was decreased and eventually stopped at 14 years old. 123I Thyroid scan demonstrated a diffuse goiter with homogeneous up take of radio labeled iodine, the up take rate was 60% at 24 hours. His TRAb level was 62.5%. Having confirmed hyperthyroidism, the boy was placed on anti thyroid drugs.