Measuring thyroxine and thyrotropin simultaneously in a dried blood sample on filter paper, to screen for neonatal hypothroidism

Journal Article · Thu May 01 04:00:00 EDT 1980 · Clin. Chem. (Winston-Salem, N.C.); (United States)

OSTI ID:6058101

Nagataki, S ^[1]; Ishibashi, K; Ohsawa, R

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1. Univ. of Tokyo, Japan

A highly sensitive radioimmunoassay of thyroxine and thyrotropin for mass screening for neonatal hypothroidism was developed. This assay involves a single disc (3 mm diameter) of dried blood on filter paper. The minimum detectable concentrations are 15 pg/tube (10 )g/L) for thyroxine and 15 nano-int. units/tube (10 milli-int. units/L) for thyrotropin; intra- and interassay CV's are <15% in both assays. The high sensitivity of this method is due to use of labeled thyroxine with high specific activity (3 kCi/g) and of an anti-thyrotropin serum with high affinity (K/sub eq/ = 7.8 x 10 rr L/mol). With this method, 1137 newborns were screened; a follow-up study revealed that only newborns with both high thyrotropin and low thyroxine concentrations had permanent hypothyroidism. It is concluded that this method is sensitive, simple, and reliable and that the recall rate with this method is much lower than that of tests for measuring thyroxine or thyrotropin alone.

• OSTI ID: 6058101
• Journal Information: Clin. Chem. (Winston-Salem, N.C.); (United States), Journal Name: Clin. Chem. (Winston-Salem, N.C.); (United States) Vol. 26:6; ISSN CLCHA
• Country of Publication: United States
• Language: English

Related Subjects

550601* -- Medicine-- Unsealed Radionuclides in Diagnostics
62 RADIOLOGY AND NUCLEAR MEDICINE
AGE GROUPS
AMINO ACIDS
BIOLOGICAL MATERIALS
BLOOD
BODY FLUIDS
CARBOXYLIC ACIDS
CHILDREN
DIAGNOSIS
DISEASES
ENDOCRINE DISEASES
HORMONES
HYPOTHYROIDISM
INFANTS
ISOTOPE APPLICATIONS
MATERIALS
MEASURING METHODS
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC HALOGEN COMPOUNDS
ORGANIC IODINE COMPOUNDS
PEPTIDE HORMONES
RADIOASSAY
RADIOIMMUNOASSAY
SCREENING
THYROID HORMONES
THYROXINE
TRACER TECHNIQUES