Monitoring lymphocyte counts in a patient with HIV infection is one way to assess the degree of immunosuppression and the risk of developing opportunistic infections.

For several years after exposure to human immunodeficiency virus (HIV), an infected person will typically have either no symptoms or only minor ones such as chronically swollen lymph nodes. However, despite the absence of noticeable symptoms, HIV may be silently causing damage.

HIV infects and kills certain white blood cells called...