Wiskott-Aldrich syndrome (WAS) is a rare, inherited immunodeficiency disorder primarily affecting males, characterized by a triad of symptoms: eczema, thrombocytopenia (low platelet count), and immune deficiency. This X-linked condition stems from a mutation in the WAS gene, which provides instructions for making the Wiskott-Aldrich syndrome protein (WASp).
Understanding Wiskott-Aldrich Syndrome
Here's a more detailed breakdown:
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X-Linked Inheritance: WAS is X-linked, meaning the faulty gene is located on the X chromosome. Males have one X chromosome, so if they inherit the mutated WAS gene, they will develop the syndrome. Females have two X chromosomes and can be carriers of the mutation without showing symptoms, or they may have milder symptoms.
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WASp Protein: The WASp protein is essential for the proper function of blood cells, particularly those involved in the immune system and blood clotting. It plays a crucial role in organizing the cytoskeleton, which is a network of protein filaments that gives cells their shape and allows them to move and communicate.
Key Characteristics
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Immunodeficiency: Individuals with WAS are highly susceptible to infections, including bacterial, viral, and fungal infections. This is due to defects in both B cells (which produce antibodies) and T cells (which help regulate the immune response).
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Thrombocytopenia: Low platelet count leads to problems with blood clotting. This often manifests as easy bruising, prolonged bleeding after injuries, and a higher risk of internal bleeding.
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Eczema: A chronic, itchy rash is a common symptom of WAS.
Diagnosis
Diagnosis typically involves:
- Clinical evaluation: Assessing symptoms like eczema, easy bruising, and recurrent infections.
- Blood tests: To check platelet count, immune cell function, and antibody levels.
- Genetic testing: To identify mutations in the WAS gene.
Treatment
Treatment options include:
- Preventive measures: Prophylactic antibiotics and antifungal medications to prevent infections.
- Intravenous immunoglobulin (IVIG): To boost antibody levels.
- Platelet transfusions: To manage bleeding episodes.
- Splenectomy: Removal of the spleen, which can help increase platelet counts in some cases. (However, it increases the risk of infection.)
- Hematopoietic stem cell transplantation (HSCT): This is the only curative option. HSCT replaces the patient's defective blood cells with healthy cells from a donor.
- Gene Therapy: Emerging research is exploring gene therapy to correct the WAS gene mutation.
Prognosis
The prognosis for individuals with WAS varies depending on the severity of the disease and the availability of treatment. HSCT offers the best chance for long-term survival and a normal quality of life.
