[Cystinosis, hyperparathyroidism and metastatic calcifications (author's transl)]

An 11-year-old boy died from uraemia in the course of cystinosis. In addition to the renal lesions common to this disease he had also developed nodular hyperplasia of the parathyroids and widespread extra-osseous calcifications in lungs, kidneys, stomach, the muscular arteries, skin and subcutaneous tissue. The calcifications and other features suggest that the hyperparathyroidism was a "tertiary" one, although this term is not generally accepted. The unusual cutaneous calcifications were probably due to calciphylaxis. As in this case, hyperparathyroidism and calcinosis can develop into a "second disease" which, due to the cystinosis, may follow a remarkably autonomous course.