Urinary Sulfate Excretion in Children with Classic Renal Tubular Acidosis

Abstract

These studies quantitate the significantly elevated sulfate excretion in the urine of children with classic renal tubular acidosis as compared to six weight-matched controls (1.4 ± 0.5 vs. 0.7 ± 0.2 mEq/kg/day;p < 0.05).This sulfate loss may result in a subclinical sulfate deficiency which may contribute to a chondroitin sulfate metabolic disorder, and thus contribute to the growth failure in children with renal tubular acidosis. Furthermore, elevated urinary sulfate excretion may be an early diagnostic finding in infancy prior to the manifestation of renal acidification defects. It is not known whether the sulfate loss is related to a primary renal tubular defect or secondary to metabolic acidosis, although the increased sulfate excretion persisting after correction of metabolic acidosis would tend to suggest a primary defect. However, the normal plasma sulfate concentration and the relatively short period of study permit no definitive answer at this time.