What is a common opportunistic infection in HIV patients?

Candidiasis is a common opportunistic infection in individuals with HIV due to the immunocompromised state associated with the disease. HIV targets and destroys CD4 T cells, which are crucial for the immune response. When the CD4 cell count drops below a certain threshold, the body becomes more susceptible to infections that would typically be managed by a healthy immune system. Candidiasis, caused by the overgrowth of Candida species, often manifests as oral thrush or candidal esophagitis in HIV patients, particularly when the CD4 T cell count falls below 200 cells/mm³.

Other infections listed, like pneumonia, can also occur but typically refer to different types of pneumonia, such as pneumocystis pneumonia, which is indeed opportunistic, although not as broadly classified as candidiasis. Influenza is not classified as an opportunistic infection but rather a viral infection that everyone can get, regardless of immune status, and herpes is a viral infection that can reactivate in immunocompromised individuals; however, it does not have the same incidence or implications as candidiasis in the context of HIV. Therefore, candidiasis stands out as a classic opportunistic infection in this patient population.