Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) Glycogen storage disease type 4 ?
    ### Response:
    Glycogen storage disease type 4 (GSD 4) is part of a group of disorders which lead to abnormal accumulation of glycogen (a storage form of glucose) in various parts of the body. Symptoms of GSD 4 usually begin in infancy and typically include failure to thrive; enlarged liver and spleen (hepatosplenomegaly); and in many cases, progressive liver cirrhosis and liver failure.
    