Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) Cushing disease ?
    ### Response:
    Cushing disease is a condition caused by elevated levels of a hormone called cortisol. It is part of a group of diseases known as Cushings syndrome. The signs and symptoms include weight gain around the trunk and in the face, stretch marks, easy bruising, a hump on the upper back, muscle weakness, tiredness, thin bones that are prone to fracture (osteoporosis), mood disorders and memory problems.
    