This information is provided by the National Institutes of Health (NIH) Genetic and Rare Diseases Information Center (GARD).
Idiopathic CD4 positive T-lymphocytopenia (ICL) is a rare disorder of the immune system. People with ICL have low levels of a type of white blood cell, called a CD4+ T cell. These low levels can not be explained by other causes of immunodeficiency, including HIV infection. T cells have many jobs in our immune system, such as attacking bacteria and viruses. CD4 is a protein found on the surface of many different cells within your immune system. It lets the different cells of your immune system work with each other. When CD4+ T cells are decreased, your body becomes more prone to infection.
Signs and Symptoms of ICL vary. Some people have no symptoms, however most have illnesses suggestive of a lowered immune system, including infections (varicella-zoster virus, human papilloma virus), autoimmune disorders (autoimmune hemolytic anemia, lupus), and certain types of cancer (non-Hodgkin lymphoma). A few people with ICL are found to carry specific gene mutations; however, for most cases of ICL the underlying cause is not known. Currently, there is no cure for ICL, but treatments are available to help manage individual symptoms.
For more information, visit GARD.