<prompt> A child rapidly develops hypoglycemia after moderate activity. On physical examination, kidney and liver are found to be enlarged. Histopathology of liver shows deposits of glycogen in an excess amount. Blood examination reveals raised ketone bodies, lactic acid and triglycerides. Which enzyme is deficient in this patient?Glycogen synthaseEndoplasmic reticulum glucose-6-phosphate transporterGlucose-6-phosphataseLiver phosphorylase kinase  <response>: Type Ia GSD-Von Gierkes Disease:Most common Glycogen Storage Disorder GSD in childhood.Autosomal recessive.Glucose 6-phosphatase is deficient.The biochemical hallmarks are:HypoglycemiaLactic acidosisHyperlipidemiaHyperuricemiaClinical Presentation:Most commonly present at 34 months of age with:Doll like facies with fat cheeksRelatively thin extremitiesShort stature, protuberant abdomenMassive hepatomegalyKidneys are also enlargedNo splenomegalyPlasma may be milky due to associated hypertriglyceridemia.Key Concept: Glucose 6-phosphatase is deficient in Von Gierkes disease. It is the most common glycogen storage disorder in childhood.Reference- Harpers illustrated biochemistry. 30th edition page no: 179 