Wiskott-Aldrich syndrome is characterized by abnormal immune system function (immune deficiency), eczema (an inflammatory skin disorder characterized by abnormal patches of red, irritated skin), and a reduced ability to form blood clots. This condition primarily affects males.Individuals with Wiskott-Aldrich syndrome have microthrombocytopenia, which is a decrease in the number and size of blood cells involved in clotting (platelets). This platelet abnormality, which is typically present from birth, can lead to easy bruising, bloody diarrhea, or episodes of prolonged bleeding following nose bleeds or minor trauma. Microthrombocytopenia can also lead to small areas of bleeding just under the surface of the skin, resulting in purplish spots called purpura, or variably sized rashes made up of tiny red spots called petechiae. In some cases, particularly if a bleeding episode occurs within the brain, prolonged bleeding can be life-threatening.Wiskott-Aldrich syndrome is also characterized by abnormal or nonfunctional immune system cells known as white blood cells. Changes in white blood cells lead to an increased risk of several immune and inflammatory disorders in people with Wiskott-Aldrich syndrome. These immune problems vary in severity and include an increased susceptibility to infection from bacteria, viruses, and fungi. People with Wiskott-Aldrich syndrome are at greater risk of developing autoimmune disorders, such as rheumatoid arthritis, vasculitis, or hemolytic anemia. These disorder occur when the immune system malfunctions and attacks the body's own tissues and organs. The chance of developing certain types of cancer, such as cancer of the immune system cells (lymphoma), is also increased in people with Wiskott-Aldrich syndrome.Wiskott-Aldrich syndrome is often considered to be part of a disease spectrum with two other disorders: X-linked thrombocytopenia and severe congenital neutropenia. These conditions have overlapping signs and symptoms and the same genetic cause.