[Scleroderma and thyroid diseases]

The authors report a prospective study of the thyroid function of 18 consecutive patients with systemic scleroderma and 7 patients with morphea. A history was taken and patients were examined for thyroid disease. The patients were tested for free thyroxin, TSH, cholesterolemia, circulating TeBG, anti-microsomial and anti-thyroglobulin antibodies and had a TRH test. The incidence of thyroid diseases was correlated with an age and sex-matched control population consisting of 2,534 subjects of the Loire department. None of the patients with morphea had a history of thyroid pathology and the thyroid screenings were within normal limits. A familial history of thyroid disease was found in 7 out of 18 patients with systemic scleroderma, and 8 out of 18 patients had a thyreopathy (one Hashimoto's disease, one Graves' disease, one toxic adenoma, one hypothyroidism, two euthyroid goiters, two nodular thyroids). The TRH test only revealed a toxic adenoma. A thyroid disease preceded systemic scleroderma in 5 out of 18 cases with delays ranging from 1 to 38 years. In 3 cases, the thyroid disease occurred within two years after the onset of systemic scleroderma. The prevalence of thyroid disease was significantly higher than in a comparable population sample of subjects from the same geographic region (p less than 0.01). The authors review the literature and discuss the physiopathologic relationships between the two clinical entities. The authors suggest to perform a thyroid screening (ultrasensitive TSH assay) on all patients with systemic sclerosis and especially on those whose clinical follow-up is atypical and on those with a familial and/or personal history of thyroid disease.