Urinary excretion of lysosomal arylsulfatases in kwashiorkor

Abstract

Arylsulfatase activity in urine specimens from children with kwashiorkor was found to be significantly higher than in urine specimens from normal children belonging to the same age group. A marked reduction in activity was observed when the children recovered. Arylsulfatase excretion in urine increased when the children with kwashiorkor were maintained on vitamin A-free diet. Intramuscular administration of watermiscible vitamin A palmitate was followed by a rapid decrease in arylsulfatase excretion. Differential assays of arylsulfatases A and B showed that the high arylsulfatase activity of urine in kwashiorkor was mainly due to the increased excretion of arylsulfatase A. The excretion pattern of arylsulfatase A changed significantly during recovery while that of arylsulfatase B remained relatively unchanged. It is possible that in kwashiorkor there is a specific metabolic disturbance in certain tissues causing a more rapid release of arylsulfatase A from the lysosomes, as compared to B. The degenerative changes in the liver and kidney observed in kwashiorkor may be at least partly responsible for the increased urinary excretion of arylsulfatases.