A CD4 count is typically reported as a count of cells (expressed as cells per cubic millimeter of blood). Sometimes results are expressed as a percent of total lymphocytes (CD4 percent). A normal CD4 count ranges from 500–1,200 cells/mm3 in adults and teens.

What is a dangerously low CD4 count?

The CD4 cell count of a person who does not have HIV can be anything between 500 and 1500. When the CD4 count of an adult falls below 200, there is a high risk of opportunistic infections and serious illnesses.

What causes CD4 to be low?

Purpose of review: A severe decrease of CD4 T cells predisposes humans to opportunistic infections. In adults, HIV is certainly the most common cause of CD4 lymphocytopenia, but other causes, such as infections, autoimmune diseases, immunosuppressive therapy, lymphoma and idiopathic forms need to be considered.

What happens when your CD4 count is high?

A higher number indicates a stronger immune system. The CD4 cell count of a person who does not have HIV can be anything between 500 and 1500. People living with HIV who have a CD4 count over 500 are usually in pretty good health.