Thyroid function in patients with Pendred’s syndrome

Abstract

Thyroid function was studied in 17 unrelated patients with Pendred's syndrome. Fourteen patients had been treated with L-thyroxine, which was withdrawn during the investigation. Eight of the patients had previously had a thyroid resection. Thirteen patients had goiter at the time of study. The serum total thyroxine and serum total triiodothyronine concentrations were normal in 8, of whom 3 had elevated serum TSH concentrations. In the remaining 9 cases the thyroxine levels were below normal with elevated TSH. Serum reverse triiodothyronine concentrations were decreased in 8 out of 11. Median serum thyroglobulin was 973 micrograms/l (range 10.9-3200 micrograms/l) and increased in 13. Three patients had slightly positive thyroglobulin antibodies and one with normal level was thyrodectomized. Thyroid stimulating antibodies as measured by adenylate cyclase stimulation (median 114%, range 85-137%) were slightly increased in 11. When measured as TSH binding inhibiting immunoglobulins none were positive. Thyroid microsomal antibodies were negative in all. All patients with a detectable 131I uptake (n = 15) showed a pathological iodide perchlorate discharge test (median 32%, range 16-46%). These findings indicate an organification defect with impaired hormone synthesis.

SLC26A4 expression among autoimmune thyroid tissues

“…However, the occurrence of Graves' hyperthyroidism in patients with PS has been reported (Ibrahim et al, 2009). In addition, the familial concurrence of PS and AITD, and the anti-TSHR aAb detection in PS sera has been described (Vaidya et al, 1999;Friis et al, 1988). Thus, PDS could be a common genetic component for the two pathologies (AITD and PS) explaining, therefore, this clinical overlapping signs on the thyroid affection.…”

Phenotypes associated with replacement of His by Arg in the Pendred syndrome gene

“…Increased serum thyroglobulin has been reported in Pendred syndrome (5,23). This might mirror the activity of the thyroid gland in terms of hormone production.…”

Clinical and molecular analysis of three Mexican families with Pendred's syndrome

“…Of note, two patients (II-1 in family 1; II-5 in family 2) had overt hypothyroidism. The absence of thyroid antibodies in individual II-1 of family 1 suggests that the hypothyroidism was caused by the organification defect itself, and not by concomitant autoimmune thyroid disease, a recognized confounding entity in patients with Pendred's syndrome (23,24). Autoimmune thyroid disease could not be excluded in individual II-5 of family 2.…”

“…The affected patients of family 1 and patient II-5 of family 2 were hypothyroid. Given the absence of antibodies against thyroperoxidase and thyroglobulin, it seems unlikely that the patient of family 1 had concomitant autoimmune thyroid disease, a combination that has been reported in other patients with Pendred's syndrome (23,24). Autoantibodies could not be measured in the hypothyroid patient of family 2, and therefore it is Haplotype analysis revealed that the index patient II-4 is homozygous for microsatellite markers flanking the PDS locus.…”