The association of hyperuricemia with type 1 glycogen storage disease (GSD) has been well established in both pediatric and adult patients.1,2 Acute gouty arthritis, tophaceous gout, and urate nephropathy are complications of hepatic glucose-6-phosphatase deficiency that may occur in the occasional patient surviving to adolescence or adulthood.3-7 In most instances, the disease presents a striking clinical syndrome during childhood and is readily diagnosed by the pediatrician. A history of failure to thrive, symptomatic fasting hypoglycemia, convulsions, episodic acidosis, and recurrent epistaxis is usually obtained; physical examination discloses short stature with normal body proportions, massive hepatomegaly, abdominal protuberance, eruptive xanthomata, and obesity. Associated biochemical abnormalities include marked hypoglycemia, acidosis, and elevations of blood lactate, triblyceride, cholesterol, free fatty acid, and uric acid.8,9 This report describes the case of an adult patient in whom childhood manifestations of glucose-6-phosphatase deficiency were mild and unrecognized; when she was age 39, tophaceous