HIV
A chronic retroviral infection that progressively impairs CD4-mediated immunity, but is now usually controllable with antiretroviral therapy that protects health and prevents sexual transmission when viral suppression is sustained.
Definition
Human immunodeficiency virus (HIV) is a chronic retroviral infection that progressively impairs CD4 T-cell-mediated immunity. Untreated infection can progress to advanced HIV or AIDS, defined by severe immunodeficiency and/or specific opportunistic infections and malignancies; effective ART suppresses replication but does not eradicate the virus.
First principles
HIV disease reflects viral replication and loss of immune coordination
HIV enters cells using CD4 and a co-receptor, reverse-transcribes its genome and establishes persistent infection. Ongoing replication, immune activation and infected-cell loss progressively impair CD4 T-cell function. The clinical risk therefore depends on both viral replication and the degree and duration of immune suppression, rather than on symptoms alone.
This page is exam revision material, not medical advice, and must not be used for patient care. Always check drug doses against the BNF and current guidance. Full disclaimer.