Diabetes mellitus-associated glycogen storage hepatomegaly: report of a case and review of the Japanese literature

A huge hepatomegaly was seen in a 30-yr-old female diabetic who was treated with high dose of insulin for her uncontrollable food ingestion. The liver function at the peak of the hepatic enlargement showed a moderate increase of transaminases, alkaline phosphatase, and gamma-glutamyl transpeptidase. The histology of the enlarged liver revealed PAS-positive granules in enlarged hepatocytes, indicating the presence of massive glycogen storage. On admission, she was maintained under a calorie-restricted diet and received approximately 15 to 20 units per day of insulin supplement. At one month after admission, a marked shrinkage of her enlarged liver and restoration of normal liver function were observed concomitantly with the return of fair control of her blood sugar levels. One year later, she had an episode of diabetic ketoacidosis which subsequently was treated with a continuous low-dose infusion of insulin; however, she showed neither hepatomegaly nor liver dysfunction during this episode. There have been 20 cases reported of Japanese diabetics with marked hepatomegaly, in whom the vigorous treatment of diabetic ketoacidosis with insulin seemed to be a trigger of the enlarged liver. This has occurred mostly in patients with insulin-dependent diabetes mellitus. We present a case of non-insulin-dependent diabetes mellitus with glycogen storage hepatomegaly, presumably due to excessive insulin supplements. This suggests that glycogen storage hepatomegaly in diabetics may not be only due to an acute restoration from diabetic ketoacidosis, but may also be due to an overinsulinization in an attempt to maintain a euglycemic condition in spite of excess food intake.