Obesity and Reversed Growth Retardation in a Child with Type Ia Glycogen Storage Disease

Type Ia Glycogen storage disease is an autosomal recessive hepatic metabolic disease due to a lack of glucose-6-phosphatase (G-6-Pase) activity presenting with growth retardation, lactic acidosis, fasting hypoglycemia with hypoinsulinemia, hyperuricemia, hepatomegaly, and hepatic adenoma with a risk of malignancy. The gene that encodes G-6-Pase was mapped to 17q21. There are some genotype-phenotype correlations. We report a case with delF327 mutation which is devoid of G-6-Pase activity; however clinical presentation in this case differs somewhat. Although correction of hypoglycemia and lactic acidosis with nocturnal intragastric feeding and uncooked starch therapy improves growth failure, mean height of the patients is often less than the target. Normal height and obesity in this case with hepatic steatosis and low hepatic glycogen storage requires clinical reevaluation since there are some overlapping phenotypes between type Ia GSD and metabolic syndrome. The phenomenon may be related to insulin resistance as a consequence of early aggressive nutrition therapy with frequent low glycemic index meals.