Looking for Increased Prevalence of Hashimoto's Thyroiditis (HT)in Patients with Sarcoidosis (SAR)and Finding an Increased Rate of High Serum Levels of Thyroxine-binding Globulin (TBG)with Presumably Impaired Binding Property.

Abstract P2-566. Sarcoidosis (SAR), a multisystemic chronic inflammatory disease of unknown etiology, can be associated with Hashimoto’s Thyroiditis (HT) and /or positive serum thyroid antibodies (Tg-Ab, TPO-Ab, M-Ab). We have realized that our series of 12 Caucasian patients (age 42-78 years) with skin biopsy proven SAR would represent an ideal group to look for the said association. In fact, all patients come from the same geographical area, are in the same stages (I or II) of the disease and most of all have an equal distribution of gender (6 men, 6 women) and no familial or personal history of thyroid disease.upon consent, patients were sampled twice a months, apart to measure serum Tg-Ab, TPO.Ab, M-Ab, TSH, T3, T4, FT3, FT4, TBG. Bilirubin and liver enzymes were also assayed, and all were normal except GGT in a few patients (see below). Thyroid ultrasonography (US) was also performed. Data are m ± SD,based on the two assays. Only one 78-yr- old woman had + ve Ab (Tg Ab=306 and 300 U/ml, nv<100). Serum TSH, FT3 and FT4 were normal (1.1mU/L, 2.6 pg/ml and 18.1 pmol/L). US showed a diffuse inhomogeneous echogenicity (DIE), as in typical chronic inflammations. In the 12 patients, normal were TSH (0.92 ± 0.58), FT3 (2.8 ± 0.7), FT4 (17.4 ± 3.6), T3 (1.2 ± 0.2 ng/ml) and T4 (7.3 ± 1.1mcg/dl). TBG (nv 13-24 mg/L in men and postmenopausal women, 13-30 in premenopausal women) was normal in 1 man (≤23.1). Of the 5 men with high TBG (range 25 - 38.4) one have mild elevated (67 U/L) and one frankly elevated (>120 U/L) GGT. Of the 3 premenopausal women, TBG was high-normal in two (27.6 – 31.4) and was normal in one (<21), who had mildy elevated GGT (46-68). TBG was high (range 27.1 – 36.2) in the 3 premenopausal women, only one having increased GGT (>97). Including the TgAb +ve woman, 7 patients (58%) had abnormal US: DIE in 4 (all women), 2 of whom with associated nodule(s), and nodule(s) without DIE in 3 women and 2 men. Thyroid biopsy could not be performed. Because histologically proven SAR infiltration of the thyroid is very rare, DIE was attributed to HT. CONCLUSIONS. In women, SAR is frequently associated (80%) with euthyroid and TgAb-veHT. The presence of thyroid nodules (50% in women, 33% in man) is in the range expected for their incidental detection. As a novel finding, 83% of men and 50% of women (all postmenopausal)have high serum levels of TBG regardless of liver damage. TBG is functionally impaired, as its increase in serum is not accompanied by any rise in T4 and T3.