Effect of prolonged steroid therapy for rheumatic fever on the exchangeable potassium content and body weight.

Serial measurements of the body weight and exchangeable potassium content were made in 13 children with acute rheumatic fever who were being treated with large doses of corticotropin or cortisone. In 8 subjects the clinical signs of hyperadrenalism developed. Seven of the 13 subjects showed at least a 20 per cent increase in body weight, which could not be explained on the basis of changes in the body's exchangeable potassium content. This weight gain is thought to be(due to an increase in total body fat.