Linear growth of children with nephrotic syndrome: effect of alkylating agents

Nephrotic syndrome is a condition that results from various diseases that injure the glomeruli, tiny coils of blood vessels in the kidneys. Characteristic features of nephrotic syndrome include spillage of protein into the urine, low levels of the blood protein albumin, and water retention (edema). For over 30 years, nephrotic syndrome has been treated with steroid drugs such as prednisone. About forty percent of the children who have this condition must take high doses of steroids for long periods of time to prevent illness relapse. Steroids can have some serious side effects, such as growth failure, cataracts, and high blood pressure. Little research has been done on the growth of children with nephrotic syndrome who are being treated with steroids. Because growth failure has been linked to steroids, another class of drugs has been recommended for treating children with nephrotic syndrome; these are the alkylating agents, such as cyclophosphamide and chlorambucil. The growth of twelve children was assessed before and after a period of treatment with cyclophosphamide or chlorambucil, supplemented by prednisone on alternate days. The combination of drugs constituted a break from continuous high-dose steroids, and it was expected that growth might improve during this time. The average age of the group was six years. Growth in height was about 4.3 centimeters (cm) per year before the combined drug regimen, and 8.7 cm per year after treatment. Thus, reduction of steroid use and substitution of alkylating agents improved growth significantly in children with nephrotic syndrome. The side effects of the short-term use of alkylating agents were minimal, but long-term adverse effects may be a concern. Children with nephrotic syndrome who show signs of reduced growth rate should be considered for this regimen. (Consumer Summary produced by Reliance Medical Information, Inc.)