AIDS and the lung

More than 50% of HIV-infected patients suffer at least one respiratory episode during the course of their disease. In early HIV infection, when immune responses are relatively preserved, respiratory infections are similar to those found in the general population, though they occur more commonly. With progressive HIV-induced immunosuppression, the risk of opportunistic infections and tumours increases. Use of highly active antiretroviral therapy (HAART) has led to marked reductions in the incidence of HIV-associated opportunistic infections (including Pneumocystis jirovecii pneumonia, cytomegalovirus disease and Mycobacterium avium complex) and tumours (including Kaposi's sarcoma). HAART has had comparatively less impact on the incidence of bacterial pneumonia, tuberculosis and non-Hodgkin's lymphoma. Despite the development of HAART, respiratory problems continue to be a major burden of disease in those infected with HIV. Reasons for this include the limited availability of HAART worldwide (particularly in resource-poor countries), failure of prophylaxis for specific opportunistic infections, and an increasing number of patients presenting with previously undiagnosed HIV infection.