What laboratory value is used to indicate the severity of HIV infection?

The CD4 count is the laboratory value that is most directly associated with the severity of HIV infection. CD4 T cells, or helper T cells, play a crucial role in the immune system's ability to fight infections. In individuals with HIV, the virus targets and destroys these cells, leading to a decline in their numbers over time.

Monitoring the CD4 count provides important information about the immune status of an individual with HIV. A higher CD4 count indicates a healthier immune system and better ability to fight infections, while a lower count indicates a more advanced infection and a higher risk of opportunistic infections or complications, such as AIDS. Therefore, CD4 counts are used to guide treatment decisions and to assess the need for starting antiretroviral therapy.

Other laboratory values mentioned do not serve as direct indicators of the severity of HIV infection. Hemoglobin A1c reflects long-term glucose control in diabetic patients, liver function tests assess liver health, and creatinine levels provide information about kidney function. While these lab values can be important in managing overall health in a patient with HIV, they do not specifically indicate the severity of the HIV infection itself.