Definitive

Male patient with congenital thrombocytopenia (less than 70,000 platelets/mm³), small platelets and at least one of the following:

1. Mutation in WASP
2. Absent WASP mRNA on northern blot analysis of lymphocytes
3. Absent WASP protein in lymphocytes
4. Maternal cousins, uncles or nephews with small platelets and thrombocytopenia

Probable

Male patient with congenital thrombocytopenia (less than 70,000 platelets/mm³), small platelets and at least one of the following:

1. Eczema
2. Abnormal antibody response to polysaccharide antigens
3. Recurrent bacterial or viral infections
4. Autoimmune diseases
5. Lymphoma, leukemia or brain tumor

Possible

Male patient with thrombocytopenia (less than 70,000 platelets/mm³) and small platelets; or a male patient splenectomized for thrombocytopenia who has at least one of the following:

1. Eczema
2. Abnormal antibody response to polysaccharide antigens
3. Recurrent bacterial or viral infections
4. Autoimmune diseases
5. Lymphoma, leukemia or brain tumor

Spectrum of disease

Congenital thrombocytopenia with small platelets is the diagnostic hallmark of Wiskott-Aldrich syndrome. Many patients present with bloody diarrhea in the first month of life. Eczema, which occurs in some but not all patients, may be the predominant clinical problem. Otitis and sinusitis, and infections due to herpes simplex and EBV are particularly troublesome. Many patients have increased IgE and IgA, with low IgM. T cell numbers and function decline with age. There is an increased incidence of autoimmune manifestations (vasculitis, hemolytic anemia, glomerulonephritis) and tumors (leukemia, lymphoma, EBV-related brain tumor). Occasional patients have moderate thromboyctopenia (50,000 to 100,000 platelets/mm³) and no other findings.

Further information

• Patient and Family Handbook For The Primary Immune Deficiency Diseases by IDF
• Wiskott Aldrich Syndrome by The Jeffrey Modell Foundation (JMF)