The 70-year-old Master Wang’s knee was red and swollen and painful a few days ago, and he thought it was gout, but when he came to the hospital, it turned out to be “pseudo”. The first is that gout is usually accompanied by elevated uric acid, while most patients with “pseudogout” do not have high uric acid. The second is that from the age of onset, gout has a high incidence in young people, middle-aged and elderly people of all ages, while “pseudogout” is most common in middle-aged and elderly people. The acute attack of “pseudogout” occurs after crystallization from cartilage to bursa, and the causes include genetics, trauma, parathyroid surgery, etc. “Pseudogout often starts suddenly, with red, swollen, hot and painful joints, most often in the knee, and more commonly in the hip, ankle, shoulder, elbow, wrist and other large joints, occasionally involving the finger and toe joints, but rarely invades the big toe like gout, and is often a single joint acute attack. Therefore, when there is redness, heat, swelling and pain in the joints, you must go to a regular hospital to receive systematic examination to avoid misdiagnosis and omission, and not to blindly use drugs to avoid side effects and delay the best time for treatment.