Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) Polyglucosan body disease, adult ?
    ### Response:
    Polyglucosan body disease affects the nervous system. Individuals with this condition usually begin to show signs of the disorder after the age of 40. Signs and symptoms include trouble walking due to decreased sensation in the legs (peripheral neuropathy) and muscle weakness and stiffness (spasticity).
    