Human immunodeficiency virus, once it enters the body, is carried to the lymphoid tissues where both CD4+ T-lymphocytes as well as follicular dendritic cells can become infected, as shown in this diagram.
The life cycle of HIV shown with the points at which pharmacologic agents may block viral maturation, including points for inhibition of reverse transcriptase, integrase, TAT transcription, and protease, in this diagram.
Candida infections are common with AIDS, but most often appear as oral thrush, which is a nuisance but not life-threatening. Disseminated infections are uncommon, but here is a rare Candida pneumonia, which resembles a bacterial bronchopneumonia.
Toxoplasma gondii is a protozoan parasite that most often leads to infection of the brain with AIDS. The lesions are usually multiple and have the appearance of abscesses. Less commonly, T gondii infection is disseminated to other organs.
Toxoplasma gondii infection is most often manifested in the central nervous system. Multiple abscesses that are ring-enhancing with CT scans can be seen. Older abscesses can organize, as shown here grossly in brain.
Cut sections of this enlarged lymph node involved with high-grade non-Hodgkin's lymphoma in AIDS reveal a "strawberry sundae" appearance with swirls and globs of red in white. This can also be seen with extra-nodal AIDS lymphomas.