Thyroxine-binding globulin capacity and concentration evaluated from blood spots on filter-paper in a screening program for neonatal hypothyroidism.
We describe a simple method for evaluating thyroxine-binding globulin capacity and concentration from a single 1-cm blood spot on filter-paper used in a screening program for neonatal hypothyroidism. This method permits prompt diagnosis of about 90% of the infants with thyroxine-binding globulin deficiency in our abnormal low-thyroxine, low-thyrotropin population. There was excellent equivalence between results obtained by our method and by the method of Chopra et al. (J. Clin. Endocrinol. Metab. 35:565, 1972), and minimal overlap between the population with low thyroxine-binding globulin and the low-thyroxine, normal thyrotropin population. We recommend this method to all programs in which a primary thyroxine measurement is used in screening for congenital hypothyroidism.
D001800:Blood Specimen Collection; D002606:Charcoal; D003409:Congenital Hypothyroidism; D006801:Humans; D007037:Hypothyroidism / Q000175:diagnosis*; D007231:Infant, Newborn; D008403:Mass Screening; D010209:Paper; D012016:Reference Values; D013972:Thyrotropin / Q000097:blood; D013974:Thyroxine / Q000097:blood; D013975:Thyroxine-Binding Proteins / Q000032:analysis*
D013975:Thyroxine-Binding Proteins; D002606:Charcoal; D013972:Thyrotropin; D013974:Thyroxine