[Immobilisation hypercalcaemia. 1 case (author's transl)].

A 21-year-old man suffered severe (up to 15.5 mg%) and prolonged (7 months) hypercalcaemia as a result of immobilisation following severe trauma. During the period of hypercalcaemia, plasma parathormone and calcitonin levels were undetectable. A study using radioactive calcium revealed a very marked increase in bone resorption, a moderate increase in accretion and virtually no intestinal absorption. Iliac biopsy revealed dense calcification front and there was no osteoid substance. This hypercalcaemia appeared to be due to increased bone resorption, while the synthesis of osteoid substance seemed to be insufficient to permit an equivalent increase in calcium accretion.