Clinical characteristics of congenital hypothyroidism detected by neonatal screening.

: Various clinical features have been prospectively evaluated in 18 infants with congenital hypothyroidism detected by the National Taiwan University Hospital screening program from January 1990 to May 1991. During the same period of time, 24 suspected cases with normal thyroid function at referral were similarly evaluated and used as controls. Among the various clinical features evaluated, there were statistically significant differences between the two groups for the following five items: feeding problems, constipation, dry skin, umbilical hernia and enlarged posterior fontanel. However, these findings were subtle and nonspecific. Even when the neonatal hypothyroid index (Quebec) was used for evaluation, only one-half of these hypothyroid babies had scores of more than two. On the other hand, there was a statistically significant difference in the thyroid function test between the two groups whether it was determined from the filter paper spot or the serum. Our observations clearly demonstrate the difficulty in establishing a diagnosis of congenital hypothyroidism on clinical grounds only at an early age of life. This study also emphasizes the importance of biochemical screening in the early detection and treatment of hypothyroid infants.