Osteomalacia associated with renal bicarbonate loss.
Severe osteomalacia of uncertain etiology was observed in a 44-year-old woman. There was no evidence of chronic renal insufficiency, malabsorption, or of the renal tubular defects classically associated with osteomalacia. However, the dietary history suggested vitamin D deficiency and most of the biochemical findings were compatible with this condition. The unusual feature of the case was a decrease in plasma bicarbonate levels which appeared to be due to a lowered renal tubular threshold for bicarbonate reabsorption. There was no renal tubular defect with respect to hydrogen ion excretion.Rapid symptomatic and radiologic improvement occurred when the dietary intake of vitamin D was increased to approximately 200 I.U. per day and the acidosis was simultaneously corrected with sodium bicarbonate. Although no firm conclusions could be drawn about the relative importance of vitamin D deficiency or chronic acidosis in the production of the osteomalacia, the possibility that the chronic acidosis may have been a major contributing factor is discussed.
D000138:Acidosis / Q000150:complications*; D000328:Adult; D001639:Bicarbonates / Q000378:metabolism*; D001769:Blood; D005260:Female; D006801:Humans; D010018:Osteomalacia / Q000209:etiology*; D014807:Vitamin D / Q000627:therapeutic use; D014808:Vitamin D Deficiency
D001639:Bicarbonates; D014807:Vitamin D