Endocrine Abstracts

Introduction: Primary hyperparathyroidism is a frequent endocrinopathy characterized by a disorder of phosphocalcic metabolism related to an inappropriate secretion of parathyroid hormone (PTH). Parathyroid adenoma can be located ectopically and represents a particular diagnostic and therapeutic challenge. We report 2 clinical cases of ectopic parathyroid adenoma in mediastinal location.

Observations: Case 1: A 47-year-old patient without any pathological history consulted for paresthesias associated with diffuse joint pain predominantly in the shoulders. The biological assessment revealed hypercalcemia at 146 mg/l, and hypophosphatemia with hypercalciuria at 323 mg/24h. The diagnosis of primary hyperparathyroidism was confirmed by a biointact PTH 1-84 assay at 925 pg/ml on an ectopic parathyroid adenoma located in the upper mediastinum which became intensely and heterogeneously enlarged after injection of PDC measuring 44*20 mm. This nodule insinuated itself into the later-aortic-cava. The management was first medical obtaining normocalcemia followed by surgical treatment with a low cervical approach, the postoperative course was simple and the anatomopathological study was in favor of a benign parathyroid adenoma without signs of malignancy.Cas 2: This is a 59-year-old patient with recurrent renal lithiasis, the etiological finding revealed hypercalcemia at 120 mg/l on a primary hyperparathyroidism with a bio-intact PTH level at 414 pg/ml, and the cervical ultrasound localized a left posteroinferior parathyroid adenoma, the patient was operated and the anatomopathological study concluded to a parathyroid adenoma. Postoperatively, hyperparathormonemia with hypercalcemia was noted, hence the indication of parathyroid scintigraphy which revealed the presence of a mediastinal parathyroid adenoma, the patient refused the surgical treatment and she was put under medical treatment by calcimimetic (Mimpara) with a favorable clinical and biological evolution, especially of the calcemia.

Discussion-Conclusion: Primal hyperparathyroidism is a frequent pathology that requires a topographic diagnosis to rectify surgery when indicated. Ectopic parathyroid adenoma is a rare entity and the advent of new radiological techniques including parathyroid scintigraphy has allowed the topographic diagnosis of this entity.