All issues > Volume 37(6); 1994

Original Article

J Korean Pediatr Soc. 1994;37(6):832-841. Published online June 15, 1994.

Normal Blood TSH, T4 Levels in Neonates as Determined by Screening Test

In Ah IA Cha¹, Kwang Sin KS Kim¹, Kyoung Sim KS Kim¹, Young Wook YW Kim¹, Ki Bok KB Kim¹

¹Department of Pediatrics, Kwangju Christian Hospital, Kwangju, Korea

Abstract

In 1,146 term neonates without perinatal problems who were born in kwangju Christian Hospital, blood TSH levels were measured by immunoradiometric assay. In 397 term neonates among them, blood T4 levels were measured by radioimmunoassay in same specimens. 1) In normal neonates aged 3~5days, 6~10days, 11~20days and 21~28days, the TSH levels were 8.885.21(meanSD), 9.44¡¾5.16, 9.69¡¾4.98, 11.963.75IU/ml and the T4 levels were 11.41¡¾2.79, 11.37¡¾2.82, 11.19¡¾2.63, 10.51¡¾2.99g/dl, respectively. 2) No significant sex difference in TSH level was found in each age group, and TSH level did not correlate with birth weight, In neonates delivered by Cesarean section, TSH levels were lower than those of the normally delivered 3) T4 levels did not differ between both sexes, and between types of delivery ineach age group, and nor did it correlate with birth weight. 4) If the recall rate should be set at 0.2% of the total, TSH levels above 26.9IU/ml would be required to recall for serum sampling. TSH level above 2SD was 19.7IU/ml. Cutoff points of T4 levels at 1.5SD and 2SD were 5.8 and 7.2g/dl respetively, and the lowest 10th percentile was 7.4g/dl.

Keywords :TSH, T4, Neonatal screening