Pulmonary complications of HIV infection

The interaction between the human immunodeficiency virus and the host immune system dictates the establishment of chronic HIV infection and the decline of CD4+ cell counts. This, in turn, is the major determinant of the risk of respiratory opportunistic infections. The use of “higly active antiretroviral therapy” (HAART) has changed the natural history of HIV infection and the rate of HIV-associated opportunistic infections, which has declined impressively with 0.5-5.0 fold reduction of rates. Conversely, some new syndromes are now being observed at the inception of HAART, including the paradoxical response to tuberculosis treatment, exacerbation of cryptococcosis and M. avium complex lymphadenitis.