title: Finnish national screening for hypothyroidism. Few false positives, early therapy.
abstract: National cord blood screening for congenital hypothyroidism has operated in Finland with complete coverage since 1980. A low frequency of false positives, 0.08%, was achieved by supplementing the TSH screen with a T4 determination in borderline samples. Among 175188 infants the incidence of (unconfirmed) hypothyroidism was 1/2637. The median age at start of therapy was 6 days. The programme imposed a 2-3 week therapy on the false positive cases. This did not appear to cause any adverse effects. A mechanism for masking congenital hypothyroidism was observed: two athyroid infants were euthyroid at birth because of feto-fetal transfusion.
mesh_terms: D003409:Congenital Hypothyroidism; D005189:False Positive Reactions; D005312:Fetal Blood / Q000032:analysis; D005387:Finland; D006801:Humans; D007037:Hypothyroidism / Q000188:drug therapy / Q000453:epidemiology; D007231:Infant, Newborn; D008403:Mass Screening; D009313:National Health Programs; D011863:Radioimmunoassay; D013972:Thyrotropin / Q000097:blood; D013974:Thyroxine / Q000097:blood / Q000627:therapeutic use
chemical_list: D013972:Thyrotropin; D013974:Thyroxine