title: Interference in thyroid-function tests in postpartum thyroiditis.
abstract: Three women are described from a study of patients with postpartum thyroiditis whose sera gave spuriously increased concentrations of free thyroid hormone because of antibody binding of radiolabeled thyroxin (T4) and triiodothyronine (T3) analogs. All of the women showed increased serum concentrations of thyroid autoantibodies. The antibody binding of radiolabeled analogs and its effect on free T4 and free T3 assays disappeared by 48 weeks postpartum. Postpartum women who develop thyroid autoantibodies have approximately 2% prevalence of increased binding of radiolabeled analogs, which can result in an interference in thyroid hormone assays involving T4 and T3 analogs.
authors.affiliation: Department of Medical Biochemistry, University of Wales College of Medicine, Cardiff, U.K.
authors.forename: R
authors.initials: R
authors.lastname: John
authors.forename: S
authors.initials: S
authors.lastname: Othman
authors.forename: A B
authors.initials: AB
authors.lastname: Parkes
authors.forename: J H
authors.initials: JH
authors.lastname: Lazarus
authors.forename: R
authors.initials: R
authors.lastname: Hall
mesh_terms: D001323:Autoantibodies / Q000032:analysis; D005260:Female; D006801:Humans; D007743:Labor, Obstetric; D011247:Pregnancy; D011863:Radioimmunoassay; D013960:Thyroid Function Tests; D013961:Thyroid Gland / Q000276:immunology* / Q000503:physiopathology; D013966:Thyroiditis / Q000097:blood*; D013974:Thyroxine / Q000378:metabolism; D014284:Triiodothyronine / Q000378:metabolism
chemical_list: D001323:Autoantibodies; D014284:Triiodothyronine; D013974:Thyroxine