Patients in the AIDS phase will usually have a prolonged fever that lasts for more than a month. Patients with a body temperature greater than 38°C will have prolonged diarrhea, which may last for a month or more; weight loss, usually more than 10%; other opportunistic infections, such as Pneumocystis pneumonia, with cough, coughing, chest tightness, and fever; and cryptococcal meningitis, with clinical symptoms such as headache, nausea, vomiting, and low-grade fever. Therefore, for patients in the AIDS stage, the clinical manifestations vary according to the different opportunistic infections. It is necessary to clarify which opportunistic infections are present according to the clinical manifestations of the patients, and it is necessary to do relevant laboratory tests to analyze the condition comprehensively.