Red bumps on the lower legs are not specific to AIDS, but some people with AIDS may also have this symptom, which needs to be clarified by examination. Red bumps on the lower legs are usually caused by skin diseases such as urticaria and eczema, which are often accompanied by itching symptoms. AIDS is a disease caused by infection with the human immunodeficiency virus and is transmitted mainly through sexual transmission, mother-to-child transmission, and blood transmission. Clinical manifestations include unexplained fever, rash, nausea, vomiting, diarrhea, enlarged lymph nodes, and significant weight loss within six months. When secondary skin infections occur, the patient may develop red bumps on the lower legs, but this does not determine whether the patient has AIDS. If the patient has high-risk behaviors that may cause HIV infection, he or she can be tested at the infection department or the CDC. If the test result is (-), the patient is not infected with HIV. If the test result is (+), the person may be infected with AIDS.