Bannister P, Shapiro L, Faye S, Bolton R
Department of Medicine, St James's University Hospital, Leeds, UK.
Ann Clin Biochem. 1988 Jul;25 ( Pt 4):373-5. doi: 10.1177/000456328802500408.
The investigation of thyroid disease in the presence of chronic liver disease (CLD) is difficult. Conventional tests are influenced by chronic illness and abnormal concentrations of binding proteins. A three tier system is normally used; thyroxine (T4), then T3 or TSH and an index for binding proteins. The recently introduced TSH immunoradiometric assays (IRMA) offer the potential of a single test assessment of thyroid function. This was assessed by the measurement of T4, T3, THBC and the free thyroxine indices in subjects with CLD. Conventional tests showed a high number of abnormal T4 values but binding indices were normal. The TSH-IRMA results were all normal. TSH-IRMA assays are rapid, easy to use and cheap. They remove the uncertainties in assessing thyroid function in CLD and may be the test of choice.
