Acute renal failure in an infant with partial deficiency of hypoxanthine-guanine phosphoribosyltransferase.

A three week old boy presented with pneumonia, weight loss, metabolic acidosis and renal failure (serum creatinine 3.1 mg/100 ml, uric acid 11.5 mg/100 ml). Renal biopsy revealed severe crystal nephropathy. Low activity of hypoxanthine-guanine phosphoribosyltransferase (HPRT) in erythrocytes and fibroblasts suggested a partial deficiency of the enzyme. A family study proved the mother to be heterozygous and the maternal grandfather to be hemizygous for HPRT deficiency. The grandfather developed gouty nephropathy and uraemia. The propositus was treated with allopurinol and kept on low purine diet and high fluid intake with sodium bicarbonate. Thereafter GFR gradually improved. At the age of two and a half years, growth and psychomotor development were normal, but ultrasound examination still revealed a dense renal parenchyma. Partial HPRT deficiency is a newly recognised treatable form of renal failure in the newborn.