Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) Sjogren syndrome ?
    ### Response:
    Sjgren syndrome is an autoimmune disorder in which immune cells attack and destroy the glands that produce tears and saliva. Sjgren syndrome is also associated with rheumatic disorders such as rheumatoid arthritis or systemic lupus erythematosus. The hallmark symptoms of the disorder are dry mouth and dry eyes.
    