Assistant Professor Texas Children's Hospital Houston, Texas, United States
Disclosure(s):
Morgan B. Lee, MD: No relevant relationships to disclose.
Introduction: Parathyroid cysts are uncommonly encountered neck masses and seldom seen in pediatric populations. Here we report a unique case of a pediatric patient with primary hyperparathyroidism from a cystic parathyroid adenoma.
Methods: A 12-year-old female presented to nephrology clinic with recurrent kidney stones, bone pain, and constipation. Parathyroid hormone (PTH) and Calcium (Ca) levels were elevated at 953 and 12.4 respectively. A thyroid ultrasound was performed and noted a 1.4cm simple cyst at the posterioinferior left thyroid gland. A distinct parathyroid lesion was not identified. Sestamibi scan and single-photon emission computerized tomography (SPECT) showed radiotracer accumulation in this area concerning for parathyroid adenoma. Patient was taken to the operating room for parathyroidectomy. Due to concern for thyroid cyst near the suspected adenoma, parents were consented for hemithyroidectomy as well as gland exploration.
Results: Initial intraoperative PTH level was 1,721. A 1.5cm cystic lesion was encountered adjacent to the left inferior thyroid lobe. A plane was encountered between the cystic lesion and the thyroid gland, and the cyst was removed en bloc. PTH levels at 10 minutes and 30 minutes post-excision were 214 and 120. Frozen pathologic examination of the specimen confirmed hyperplastic parathyroid tissue. Final pathology confirmed a 2.7g cystic parathyroid adenoma. The patient was admitted postoperatively until Ca levels stabilized on oral Ca supplementation.
Conclusions: Here we describe a hyperfunctional parathyroid cyst in a pediatric patient. 9 cases of pediatric parathyroid cysts have been reported in the literature, all nonfunctional. Approximately 300 cases of parathyroid cysts have been reported in the adult literature, with 10-15% of those being hyperfunctional lesions. This finding was significant as the patient was consented for possible hemithyroidectomy due to concern for thyroid cyst. Parathyroid cysts are much less commonly encountered than thyroid cysts and a hyperfunctional parathyroid cyst has not previously been described in a pediatric patient.
