Below is an instruction from Human. Write a response.
    ### Instruction:
    How to diagnose Gout ?
    ### Response:
    To confirm a diagnosis of gout, the doctor inserts a needle into the inflamed joint and draws a sample of synovial fluid, the substance that lubricates a joint. A laboratory technician places some of the fluid on a slide and looks for uric acid crystals under a microscope.
    