HIV-1–Associated Opportunistic Infections

Excerpt

Human immunodeficiency virus (HIV) is a retrovirus known to attack the CD4+ T lymphocytes. Of the two subtypes, HIV-1 and HIV-2, the former is common and prevalent worldwide, and the latter is confined to West Africa and hence less common. In individuals with chronic HIV infection not on treatment with antiretroviral agents, as the CD4+ count drops they are vulnerable to a multitude of infections which rarely occur in an immunocompetent host, hence the term opportunistic infections (OIs). The presence of an AIDS-defining illness or CD4+ less than 200 cells/mm³ is necessary for defining AIDS and the literature describes potentially fatal opportunistic infections in these patients which are often challenging to treat.