Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) Lupus nephritis ?
    ### Response:
    Lupus nephritis is a kidney disorder that is a complication of systemic lupus erythematous (SLE), commonly known as lupus. The symptoms of lupus nephritis include blood in the urine, a foamy appearance to the urine, high blood pressure, and swelling in any part of the body.
    