Secondary hyperparathyroidism as a palpable intrathyroid parathyroid gland in a patient with hypophosphatemic osteomalacia.

Secondary hyperparathyroidism is sometimes seen in patients with hypophosphatemic osteomalacia after long-term oral phosphate therapy. Parathyroidectomy is sometimes needed for the correction of hypercalcemia in these patients, and is rarely performed in patients without hypercalcemia. A 46-year-old female patient had hypophosphatemic osteomalacia with unknown cause and secondary hyperparathyroidism. A palpable neck mass developed after long-term oral phosphate therapy. An intrathyroid parathyroid gland was confirmed through partial thyroidectomy and parathyroidectomy. Renal phosphate wasting decreased strongly, and serum parathyroid hormone was in the normal range after the operation. A correction of secondary hyperparathyroidism may partially overcome hyperphosphaturia in some patients with hypophosphatemic rickets.