Renal tubular acidosis associated with vitamin D-resistant rickets. Role of phosphate depletion.

3 children with vitamin D-resistant rickets (VDRR), and severe phosphate depletion had moderate metabolitic acidosis and evidence of impaired distal tubular acidifying mechanisms. Therapy with 1-alpha-OH-vitamin D3 and phosphate supplementation improved the clinical and radiological rachitic manifestations, and resulted in the normalization of systemic acid-base parameters as well as of tubular acidification. Profound phosphate depletion is another cause of acquired, reversible distal renal tubular acidosis (RTA).