1. HIV AIDS Myths and Facts Slideshow Pictures
2. Take the HIV/AIDS Quiz
3. AIDS Retrospective Slideshow Pictures

Medical Author:

Mary D. Nettleman, MD, MS, MACP

Mary D. Nettleman, MD, MS, MACP

Mary D. Nettleman, MD, MS, MACP is the Chair of the Department of Medicine at Michigan State University. She is a graduate of Vanderbilt Medical School, and completed her residency in Internal Medicine and a fellowship in Infectious Diseases at Indiana University.

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Medical Author:

Rowena A. Medina, MD

Medical Author:

Eric S. Daar, MD

Eric S. Daar, MD

Dr. Daar received his undergraduate degree from UCLA and medical degree from Georgetown University School of Medicine. He completed an internship and residency in internal medicine at Cedars-Sinai Medical Center and his clinical and research fellowship in infectious diseases at Cedars-Sinai Medical Center and UCLA.

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Medical Editor:

Jay W. Marks, MD

Jay W. Marks, MD

Jay W. Marks, MD, is a board-certified internist and gastroenterologist. He graduated from Yale University School of Medicine and trained in internal medicine and gastroenterology at UCLA/Cedars-Sinai Medical Center in Los Angeles.

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In this Article

• Acquired immunodeficiency syndrome (AIDS) facts
• What does AIDS stand for? What causes AIDS?
• What is the history of AIDS?
• What are symptoms and signs of AIDS?
• What are risk factors for developing AIDS?
• How is AIDS diagnosed?
• What is the treatment for HIV/AIDS?
• What is the treatment for HIV during pregnancy?
• What is the treatment for non-HIV-infected people who are exposed to the genital secretions or blood someone with HIV?
• What are the complications of HIV?
• What is the prognosis for HIV infection?
• Can HIV infection be prevented?
• Is there a vaccine for HIV?
• What research is being done to find a cure for HIV?
• Where can a person find information about clinical trials for HIV and AIDS?
• HIV-AIDS FAQs
• Patient Comments: AIDS - Experience
• Find a local Infectious Disease Specialist in your town
• Acquired Immunodeficiency Syndrome (AIDS) Index

AIDS is an advanced stage of HIV infection. Because the CD4 cells in the immune system have been largely destroyed, people with AIDS often develop symptoms and signs of unusual infections or cancers. When a person with HIV infection gets one of these infections or cancers, it is referred to as an "AIDS-defining condition." Examples of AIDS-defining conditions are listed in Table 1. Significant, unexplained weight loss also is an AIDS-defining condition. Because common conditions like cancer or other viral conditions like infectious mononucleosis also can cause weight loss and fatigue, it is sometimes easy for a physician to overlook the possibility of HIV/AIDS. It is possible for people without AIDS to get some of these conditions, especially the more common infections like tuberculosis.

People with AIDS may develop symptoms of pneumonia due to Pneumocystis jiroveci, which is rarely seen in people with normal immune systems. They also are more likely to get pneumonia due to common bacteria. Globally, tuberculosis is one of the most common infections associated with AIDS. In addition, people with AIDS may develop seizures, weakness, or mental changes due to toxoplasmosis, a parasite that infects the brain. Neurological signs also may be due to meningitis caused by the fungus Cryptococcus. Complaints of painful swallowing may be caused by a yeast infection of the esophagus called candidiasis. Because these infections take advantage of the weakened immune system, they are called "opportunistic infections."

The weakening of the immune system associated with HIV infection can lead to unusual cancers like Kaposi's sarcoma. Kaposi's sarcoma develops as raised patches on the skin which are red, brown, or purple. Kaposi's sarcoma can spread to the mouth, intestine, or respiratory tract. AIDS also may be associated with lymphoma (a type of cancer involving white blood cells).

In people with AIDS, HIV itself may cause symptoms. Some people experience relentless fatigue and weight loss, known as "wasting syndrome." Others may develop confusion or sleepiness due to infection of the brain with HIV, known as HIV encephalopathy. Both wasting syndrome and HIV encephalopathy are AIDS-defining illnesses.