[Pseudohypoparathyroidism or vitamin D deficiency? Report of one case].

Pseudohypoparathyroidism is characterized by a resistance to parathormone, with variable phenotypical and biochemical manifestations. Its diagnosis is difficult. We report a 28 year old male presenting with a hypokalemic periodic paralysis. His serum PTH was elevated to 1,343 and 1,101 pg/ml with concomitant hypocalcemia of 7.9 and 6.7 mg/dl. Twenty four hour urinary calcium and serum 25 hydroxy vitamin D were normal. Bone mineral density was normal. The patient was managed with calcitriol in doses of 1 to 2 microg/d, associated to calcium 2 g/day. Serum calcium levels and PTH normalized after two months and six months of treatment respectively.