What condition is characterized by an accumulation of glycogen in tissues?

Von Gierke's Disease, also known as Glycogen Storage Disease type I, is characterized by an accumulation of glycogen in tissues due to a deficiency in the enzyme glucose-6-phosphatase. This enzyme is crucial for the conversion of glycogen to glucose, and its deficiency leads to the inability to properly mobilize glucose from stored glycogen. As a result, glycogen builds up in the liver and kidneys, causing hepatomegaly (enlarged liver) and potential kidney damage.

In addition to this main effect, the inability to release glucose leads to hypoglycemia, particularly between meals, as the body cannot maintain necessary blood glucose levels. Symptoms often include fasting intolerance, growth delays, and abdominal distention due to the enlarged liver.

The other conditions listed do not have the same mechanism leading to glycogen accumulation. Hemochromatosis involves iron overload rather than glycogen, pernicious anemia relates to vitamin B12 deficiency affecting red blood cell production, and sickle cell disease is a genetic blood disorder affecting hemoglobin. Therefore, Von Gierke's Disease is distinct in its association with glycogen accumulation in tissues.