Osteomalacia in chronic renal failure before dialysis.

Bone biopsies taken from 327 patients before the start of dialysis have been correlated with clinical and biochemical findings to test various theories about the aetiology of osteomalacia. Two groups of patients, 100 with osteomalacia and 100 with pure osteitis fibrosa, have been compared in detail. Osteomalacia is associated with chronic pyelonephritis or obstruction as primary renal disease, and with acidosis, hypocalcaemia and normophosphataemia (as opposed to hyperphosphataemia). We have found no association between osteomalacia and known duration or severity of uraemia and in a small series of observations we have not confirmed previous reports of a close association between osteomalacia and depressed plasma 25(OH) cholecalciferol values.