Aortopulmonary window parathyroid gland causing primary hyperparathyroidism in men type 1 syndrome.

Primary hyperparathyroidism (HPT) is the most common endocrinopathy in Multiple Endocrine Neoplasia type 1 (MEN1) syndrome. Supernumerary and/or ectopic parathyroid glands, potentially causes of persistent or recurrent HPT after surgery, have been previously described. However, this is the first ever described case of ectopic parathyroid gland localized in the aortopulmunary window causing HPT in MEN1. After a consistent concordant pre-operative imaging assessment the patient, a 16 years old male affected by a severe hypercalcemia, underwent surgery. The parathyroid was found very deeply near the tracheal bifurcation, hidden by the aortic arch itself and for this reason not visible at the beginning of the dissection but only after being identified by palpation for its typical consistence. The intraoperative PTH decreased at normal level 10 min after removal of the ectopic gland. The patient remained with normal value of calcemia and PTH during the 10 months of follow-up.