Eclusys ft4

TSH, FT 4 , and FT 3 levels were measured using electrochemiluminescence immunoassay (ECLusys TSH, ECLusys FT 4 , and ECLusys FT 3 , respectively; Roche Diagnostics, Basel, Switzerland). The reference values were 0.30-4.50 μIU/mL for TSH level, 0.7-1.8 ng/dL for FT 4 level, and 2.0-4.5 pg/mL for FT 3 level.

The primary outcome was GD, and the diagnosis of GD was made on the basis of an elevated serum FT3 level and FT4 level, suppression of the serum TSH level, a typical goiter, ophthalmopathy, the presence of thyroid stimulating antibody, and increased RAIU. The diagnosis of PT was made on the basis of an elevated serum FT3 level and FT4 level, suppression of the serum TSH level, negative TRAb, and decreased RAIU. FT3 and FT4 levels were measured by electrochemiluminescence immunoassays (ECLIAs) (Elecsys FT3 and ECLusys FT4, Roche Diagnostics GmbH, Basel, Switzerland; manufacturer's reference limits: 2.2-4.3 pg/mL and 0.8-1.6 ng/dL respectively). The TSH level was measured by an ECLIA (Elecsys TSH; Roche Diagnostics GmbH, Basel, Switzerland; manufacturer's reference limits: 0.2-4.5 mIU/L). Control subjects (without any thyroid diseases) were identified on the basis of normal thyroid function, i.e., FT3, FT4, and TSH levels within their reference ranges, negative test for any of the thyroid autoantibodies, homogeneous echo pattern on thyroid images, i.e., absence of thyroid nodules, and absence of goiter.

Free triiodothyronine (FT 3 ) and free thyroxine (FT 4 ) levels were measured by an electrochemiluminescence immunoassay (ECLIA) (ECLusys FT 4 , Roche Diagnostics GmbH, Mannheim, Germany; manufacturer's reference limits: 2.2-4.3 pg/mL, 0.8-1.6 ng/ dL respectively). The TSH level was measured by an ECLIA (ECLusys TSH; Roche Diagnostics GmbH, Mannheim, Germany; manufacturer's reference limits: 0.2-4.5 mIU/L). Based on the results of our previous study of a large population, the reference intervals for FT 3, and FT 4, and TSH at 4-12 weeks of gestation were 2.01-4.9 pg/mL, 0.77-1.91 ng/dL, and 0.01-3.35 mIU/L, respectively.
TPOAb and TgAb were determined by an ECLIA performed with Roche ECLusys Anti-Tg and Anti-TPO (Roche Diagnostics GmbH, Mannheim, Germany; reference values were: TPOAb, ≤28 IU/mL; TgAb, ≤40 IU/mL). Until September 30, 2008, TRAb levels were determined with a solid-phase immunoradioreceptor assay kit (RSR, Cardiff, UK; TRAb-CT; reference values <10%), but since October 1, 2008, they have been determined with an electrochemiluminescence immunoassay kit (ECLusys TRAb; Roche Diagnostics GmbH, Mannheim, Germany; reference values <2.0

Affinity chromatography was performed using a size-exclusion chromatography column (PROTEIN KW-804 [Shodex, Tokyo, Japan] with buffer (50 mM Tris-HCL, 150 mM NaCl, pH 7.2) with a flow rate 0.75 mL/min and a fraction of 30 seconds/tube. Concentrations of FT 4 , TT 4 , albumin, and TBG in each fraction were measured. FT 4 and T 4 were measured by ECLusys FT 4 or T 4 (Roche Diagnostics GmbH, Mannheim, Germany).