[Screening for hypothyroidism in the newborn with a total T 4-RIA method (author's transl)].

A screening method for detection of congenital hypothyroidism is presented in detail in cooperation with the "Austrian Program for Inborn Errors of Metabolism". Screening is performed by measuring the total T4-content of 1/8 inch filter paper dots filled with dried blood of newborns. The strategy for recall of newborns with borderline or pathological T4-values used, results in a definite diagnosis on day 55 of life. The advantages of additional TSH determination in the filter paper dots are discussed. So far (Sept. 1976) 8645 newborns have been investigated, covering the regions of Vienna and Carinthia (Austria). Preliminary studies reveal a slight dependency of the measured T4-values on the day of sampling. Two congenitally hypothyroid children have been diagnosed so far, corresponding fairly well with the reported frequency in the literature (1 : 6000).