Recurrent Renal Hyperparathyroidism due to A Subcutaneous Parathyroid Lesion: Report of A Case

Failure of a primary operation to control renal hyperparathyroidism is usually due to inadequate resection of hyperplastic tissue or previous undetected ectopic parathyroid gland. We describe a patient with recurrent renal hyperparathyroidism, who presented with a subcutaneous neck nodule. A 49-year-old woman had a history of systemic lupus erythematosus, papillary thyroid carcinoma, and end-stage renal disease with renal hyperparathyroidism, for which she subsequently received percutaneous ethanol infusion therapy to bilateral hyperplastic parathyroid lesions, a subtotal thyroidectomy and parathyroidectomy. Despite aggressive treatment with phosphate binders and vitamin D3 supplements, the levels of intact parathyroid hormone, calcium and phosphorus kept elevating during the follow-up period. Thyroid sonography revealed neither thyroid nor parathyroid tissue in the thyroid bed. Physical examination showed a palpable subcutaneous nodule at the right neck, which was hyperechoic and heterogeneous on soft tissue sonography. Technetium (Tc) sestamibi scan showed a focal hot spot at the same site. She received complete surgical resection of the neck nodule. Histopathological analysis showed parathyroid hyperplasia. Two years after removal of the nodule, the patient was well. In conclusion, to avoid recurrent hyperparathyroidism, a meticulous surgical technique is vital to successful parathyroid surgery. On the other hand, alcohol injection is not recommended for renal hyperparathyroidism if the patient can tolerate operation, because alcohol injection can cause fibrosis which makes further operation difficult in processing. We should also keep subcutaneous parathyroid lesions in mind when we perform neck re-exploration for recurrent hyperparathyroidism. (J Intern Med Taiwan 2011; 22: 206-211)