Autoimmune thyroid diseases in patients with undifferentiated connective tissue disease

Previous data have indicated that organ-specific and non-organ-specific aut oimmune diseases may occur in the same patient. We report here our study on the type and prevalence of endocrine autoimmune diseases in undifferentiat ed connective tissue disease (UCTD). A retrospective analysis revealed five out of 75 UCTD cases (6.6%) with cytology-verified autoimmune thyroiditis (associated with insulin-dependent diabetes mellitus in one case). Other UC TD patients had Graves' disease tone case), non-toxic multinodular goitre ( two cases) and central hypothyroidism tone case). In a prospective study, t hyroid function was evaluated in 15 consecutive UCTD patients with neither clinical nor laboratory signs of thyroid involvement. Basal and post-TRH st imulation TSH levels were significantly higher in UCTD patients than in hea lthy subjects.