Chronic renal failure–> decreased clearance of phosphate –> hyperphosphatemia –> decreased production of activated vitamin D (1,25 dihydroxy) –> hypocalcemia –> hyperparathyroidism –> hypercalcemia, renal osteodystrophy

hyperphosphatemia –> vascular calcifications –> calciphylaxis (necrotic skin lesions)

Men:  decreased testosterone

Women: amenorrhea, infertility, hyperprolactinemia