Endocrine Abstracts

Introduction: Primary hyperparathyroidism (PHPT) is a frequent endocrinopathy caused mostly by parathyroid adenoma. Classic manifestations, less prevalent nowadays, may have a misleading aspect. Here we describe the case of a patient presenting nephrolithiasis, multiple brown tumors revealing PHPT.

Observation: A 37-years-old female was diagnosed with nephrolithiasis treated by shockwave lithotripsy without success. CT scan showed coralliform lithiasis in addition to multiple lytic lesion in the pelvis and the fourth lumbar spine suggestive of metastasis. Bone biopsy was done revealing a brown tumors aspect. High blood level of calcium (3.46 mmol/l) and PTH (836 pg/ml) confirmed the diagnosis of PHPT associated with low 25-Hydroxy-vitamin D concentration (11.9 ng/ml). She had constipation, bone pain, asthenia and weight loss. The neck examination showed a lateral neck tumefaction corresponding to a 3 cm nodule. The ultrasonography and MIBI scan confirmed an upper left parathyroid adenoma which was resected after a medical preparation. The anatomopathological examination found an atypical adenoma due to mitosis and necrosis. After surgery, the patient developed hypocalcemia requiring alfacalcidiol and calcium supplementation. PTH level, dropped initially after surgery to 57 pg/ml, kept increasing to 187–264 pg/ml although the normal postoperative MIBI scan and the absence of hungry bone syndrome. A molecular analysis of CDC73 gene was done since the diagnosis of parathyroid carcinoma is highly suspected.

Conclusion: Palpable parathyroid tumor, high serum calcium and PTH levels must attract attention to suspect the diagnosis of parathyroid carcinoma which remains difficult to differentiate it from atypical adenoma.