Concentration of thyroxine-binding globulin: value of direct assay.

Concentration of thyroxine-binding globulin: value of direct assay.

The concentration of thyroxine-binding globulin (TBG) in the serum can now be measured by direct assays that are simple and inexpensive. Comparison of a direct measurement of TBG concentration with a widely used indirect method (Thyopac-3) showed that the indirect method was inaccurate when TBG concentrations were high. This will result in an increase in the derived free thyroxine index (FTI), ...

Assay of thyroxine-binding globulin by polyacrylamide electrophoresis: normal values.

Thyroxine-binding globulin (TBG) assays by the polyacrylamide electrophoresis assay of Nikolai and Seal have been carried out on 315 normal subjects. The assay was carried out with 200 exogenous labeled thyroxine per 100 ml added to the samples. The means and standard deviations for the three thyroxine-binding proteins in males (n = 140) were: TBG 19.7 ±3.0 p.g/100 ml, thyroxine-binding albumin...

Thyroxine-Binding Globulin Concentrations

Plasma thyroid hormone concentrations may be abnormal in non-thyroid disease and pose diagnostic problems. For example, concentrations of triiodothyronine (T3) in the blood decline in acute illness with a reciprocal increase in reverse triiodothyronine (reverse T3), but thyroxine (T4) concentrations are usually normal or only slightly decreased (1, 2). However, McLarty et al. (3) reported that ...

Familial thyroxine-binding globulin deficiency.

Genetically determined thyroxine-binding globulin deficiency is described in two families in the United Kingdom. All subjects in both pedigrees were euthyroid. Transmission was by sex-linkage; males showed low serum protein bound iodine and high thyroxine (T4) resin uptake due to complete absence of serum thryroxine-binding globulin; females were less severely affected. The distinctive biochemi...

Thyroxine-binding globulin, hyperthyroxinemia and hepatocellular carcinoma.