A red rash that does not itch may be a symptom of HIV, but the rash typically appears on the torso instead of the buttocks, according to WebMD. The rash is one of the potential initial symptoms of an HIV infection.
HIV has three stages. The first stage as acute infection or seroconversion, and people typically experience symptoms in this stage two to six weeks after infection, including nausea, diarrhea, muscle aches, fatigue and fever, explains WebMD. These symptoms are similar to those for the flu. People with HIV experience these symptoms for approximately two weeks before the virus moves into the second stage.
The second stage of HIV is the asymptomatic or latent stage, where the body's immune system loses the battle with HIV as the virus kills CD4 T-cells, according to WebMD. This stage can last over 10 years, and when a person's CD4 T-cell level drops below 200, the diagnosis changes to AIDS.
Acquired immune deficiency syndrome, or AIDS, is the final stage of HIV infection. Rapid weight loss, recurring fever, extreme tiredness, memory loss and depression are listed as symptoms, AIDS.gov reports. Some people experience blotches under the skin or inside the mouth, eyelids or nose, while others develop sores on the anus, genitals or mouth. Other infections can cause these symptoms, and the only way to diagnose HIV and AIDS is through blood tests.