Wiskott-Aldrich syndrome
- Definition: genetic condition characterized by impaired function of T cells and thrombocytopenia
- Epidemiology: occurs primarily in males
- Etiology: mutated WAS gene (X-linked recessive inheritance) → impaired signaling to actin cytoskeleton reorganization → defective antigen presentation
- Clinical features
- Onset of symptoms: from birth
- Classic triad
- Purpura (bleeding diathesis)
- Eczema (high risk of atopic disorders)
- Recurrent opportunistic infections with encapsulated organisms in the first years of life (e.g., otitis media)
- Increased risk of autoimmune diseases and hematological malignancies (e.g., lymphoma, leukemia)
Mnemonic
Purpura and eczema are like you're bit by a WASp.
- Diagnosis
- Normal or ↓ IgG and IgM
- ↑ IgE and IgA
- Thrombocytopenia with small platelets