Lungs

Coccidiomycosis — This infection is caused by inhaling an infective fungus called Coccidioides immitis, found mainly in contaminated soil in the southwestern United States, Mexico, Central America and parts of South America. The lungs are the most commonly affected by this infection. In severe cases, it can involve the kidneys, lymph system, brain and spleen. Symptoms include cough, weight loss and fatigue. Meningitis is a common complication when left untreated.
Histoplasmosis — This infection almost always involves the lungs, although other organs may be affected. The fungus that causes this condition is found in southern parts of the United States and South America. It is usually found in soil contaminated with bird droppings and must be inhaled to cause infection. Signs and symptoms include high fever; weight loss; respiratory complaints; an enlarged liver, spleen, or lymph nodes; depressed production of white cells, red blood cells and platelets from the bone marrow; and life-threatening, unstable, low blood pressure.
Pneumocystis Carinii — This condition occurs when a fungus infects the lungs. Symptoms may include fever, cough, difficulty breathing, weight loss, night sweats and fatigue. It is most likely to occur when the CD4+ T cell count falls below 200 cells per cubic millimeter of blood. Preventative treatment may be administered when the CD4+ T cell count falls below 200 cells per cubic millimeter of blood. Treatment is usually trimethoprim-sulfamethoxazole, also called Septra or Bactrim, dapsone or atovoquone.
Recurrent Pneumonia — People with AIDS are at risk for recurrent bacterial pneumonia. Bacteria can infect the lungs, which may lead to problems ranging from a mild cough to severe pneumonia. Recurrent pneumonia is most likely to occur when the CD4+ T cell count falls below 200 cells per cubic millimeter of blood.
Tuberculosis (TB) — This is a serious, and often deadly, bacterial infection that primarily infects the lungs. TB is transmitted when a person with active TB coughs or sneezes, releasing microscopic particles into the air. If inhaled, these particles may transmit the condition. Once infected by TB, most people remain healthy and develop only latent infection. People with latent infection are neither sick nor infectious. However, they do have the potential to become sick and infectious with active TB. It can occur at any CD4+ T cell level but especially when the CD4+ T cell count falls below 350 cells per cubic millimeter of blood.