First description of parathyroid disease in multiple endocrine neoplasia 2A syndrome

Pheochromocytomas and Paragangliomas

Pheochromocytomas are rare neuroendocrine tumors. Extra-adrenal lesions arising from the autonomic neural ganglia are termed paraganglioma. Clinical symptoms are common between the adrenal and extra-adrenal forms and are determined by excess secretion of catecholamines. Hypertension is a critical and often dramatic feature of pheochromocytoma/paraganglioma, and its most prevalent reported symptom. However, given the rare occurrence of this cancer, in patients undergoing screening for hypertension, the prevalence ranges from 0.1% to 0.6%. Still, patients frequently come to the attention of endocrinologist when pheochromocytoma/paraganglioma is suspected as a secondary cause of hypertension. This article summarizes current clinical approaches in patients with pheochromocytoma/paraganglioma.

Primary hyperparathyroidism as the first clinical manifestation of multiple endocrine neoplasia type 2A in a 5-year-old child

BACKGROUND

Primary hyperparathyroidism occurs in only 10%-30% of patients with multiple endocrine neoplasia type 2A (MEN2A), rarely as the sole clinical manifestation, and is usually diagnosed after the third decade of life.

SUMMARY

A 5-year-old girl was referred for prophylactic thyroidectomy as she carried the p.C634R RET mutation. She was clinically asymptomatic, with a normally palpable thyroid and with the cervical region free of lymphadenopathy or other nodules. Preoperative tests revealed hypercalcemia associated with elevation of parathyroid hormone (PTH) (calcium = 11.2 mg/dL, calcium ion = 1.48 mmol/L, phosphorus = 4.0 mg/dL, alkaline phosphatase = 625 U/L, parathyroid hormone (PTH) PTH = 998 pg/mL). A thyroid ultrasound was normal and parathyroid scintigraphy with (99m)Tc-Sestamibi revealed an area of radioconcentration in the upper half of the left thyroid lobe suggesting hyperfunctioning parathyroid tissue. She underwent total thyroidectomy and parathyroidectomy and developed hypocalcemia. The anatomopathological examination showed no histopathological changes in the thyroid tissue and an adenoma of the parathyroid gland, confirming the diagnosis of hyperparathyroidism.

CONCLUSIONS

Primary hyperparathyroidism can be a precocious manifestation of MEN2A. This case report highlights that asymptomatic hypercalcemia should be scrutinized in children related to patients with MEN2A who carry a mutation in the RET proto-oncogene, especially mutations in the codon 634, before the currently recommended age of 8 years.