Wiskott-Aldrich syndrome (WAS) is a very rare, serious, and potentially life-threatening immunodeficiency disease, characterized by thrombocytopenia, eczema, infections and an increased risk for autoimmune manifestations and hematologic malignancies. Children with WAS are diagnosed most commonly in the first 1-2 years of life because of excessive bleeding, eczema, and frequent bacterial or viral infections.
Wiskott-Aldrich syndrome is caused by mutations in the in the WAS gene (Xp11.4-p11.21), coding for a protein, now termed Wiskott-Aldrich syndrome protein (WASp), exclusively expressed in hematopoietic cells.