Endocrine Abstracts

Introduction: In the whole world normocalcemic hyperparathyroidism (NC HPT) is an emerging entity and a growing problem. This disease is characterized by high levels of intact parathyroid hormone with normal total or ionized serum calcium. Our aim is to analyze its clinical and biological profile and its etiologies.

Subjects and methods: We have studied 18 subjects with NC HPT. They all had routine analyses, plasma calcium and phosphorous, and assessment of parathyroid hormone (PTH) and vitamin D. kidney and bone explorations were done too.

Results: In this group, 16 were females (88.8%) and 2 were males. Their mean age was equal to 51.2 years (36–70), their mean plasma calcium=95 mg/l, mean phosphorous=32 mg/l, mean PTH=223 pg/ml (≤60). The consultation motive was bone problems in 33.3%. Bone mineral density was low or very low in 14 (77.7%). Recurrent kidney stones were observed in three cases=16.6%, renal insufficiency=0%. For etiologies NCHPT was due to vitamin deficiencies in 57.1% and to primitive hyperparathyroidism in 42.9%.

Conclusion: As in classical HPT, NC HPT is prevailing in female cases. In NC HPT bone lesions are more frequent than kidney problems. For etiologies, vitamin D deficiency is slightly more frequent than idiopathic primary HPT, but large series are necessary to confirm our results.