All issues > Volume 42(11); 1999

Original Article

J Korean Pediatr Soc. 1999;42(11):1487-1495. Published online November 15, 1999.

Characteristics of Transient Hypothyroidism Detected by Neonatal Screening Test

Su-Yung SY Kim¹

¹Department of Pediatrics, Pusan National University, College of Medicine, Pusan, Korea

Correspondence Su-Yung SY Kim ,Email: 1

Abstract

Purpose
: To help differentiate transient hypothyroidism from congenital hypothyroidism, both of which might be confused initially, the clinical characteristics of transient hypothyroidism were compared to those of permanent ones.
Methods
: An analysis of the clinical data, including perinatal history, TFT(thyroid function test), and radionuclide scanning, was performed. The outcome of 18 patients of transient hypothyroidism was also compared to 19 patients of congenital hypothyroidism.
Results
: Most of the patients were male(male to female ratio was 5 to 1). The majority of patients(10/18) had history of dressing their umbilical stumps with iodine containing disinfectant. They seemed to have higher titers of T3 and lower titer of TSH at initial checking compared to congenital hypothyroidism and mostly showed normal thyroid image at initial scanning using 99mTc. Five patients, whose thyroid functions were normalized in 22-97 days after birth, were followed up without treatment. Thirteen patients were treated with levothyroxine initially, but able to stop treatment with normalized thyroid function test after at least one month of treatment pause when they were 18-46 months old.
Conclusion
: Transient hypothyroidism diagnosed via neonatal screening were found in almost male neonates and had a tendency for milder abnormalities of thyroid function test compared to congenital hypothyroidism and had past history of dressing umbilical stumps in over half of the patients with iodine containing disinfectant.

Keywords :Neonate, Transient hypothyroidism