Hypoparathyroidism preceding Riedel's thyroiditis.

We report the case of a woman who presented with primary hypoparathyroidism and who subsequently developed extensive Riedel's thyroiditis. To our knowledge, this is the first reported case of primary hypoparathyroidism preceding Riedel's thyroiditis. This observation suggests that Riedel's thyroiditis is part of a diffuse fibrotic process that may involve other organs, such as the parathyroid glands.