A 10-month-old patient with recurrent pyogenic infections, eczema, and severe bleeding (thrombocytopenia) is diagnosed with Wiskott-Aldrich syndrome. This immune disorder is usually associated with which of the following?
**Question:** A 10-month-old patient with recurrent pyogenic infections, eczema, and severe bleeding (thrombocytopenia) is diagnosed with Wiskott-Aldrich syndrome. This immune disorder is usually associated with which of the following?
A. Hypogammaglobulinemia
B. Immune dysregulation
C. Autoimmune disease
D. X-linked recessive inheritance
**Core Concept:**
Wiskott-Aldrich syndrome (WAS) is a rare primary immunodeficiency characterized by the presence of recurrent infections, eczema, and bleeding disorders. It is caused by mutations in the WAS gene, which encodes for the WAS protein. This protein is crucial for the proper functioning of immune cells, particularly T and B lymphocytes, and platelets.
**Why the Correct Answer is Right:**
WAS is an X-linked recessive disorder, which means it affects males more frequently due to the X-linked inheritance pattern. Males have only one X chromosome, making them more susceptible to X-linked genetic disorders. In WAS, the mutated WAS protein impairs the immune system, leading to the clinical features mentioned above.
**Why Each Wrong Option is Incorrect:**
A. Hypogammaglobulinemia (low immunoglobulin levels) is not directly related to WAS. Although patients with WAS may have hypogammaglobulinemia, this option is not the defining feature of the syndrome.
B. Immune dysregulation is a feature of WAS, as it affects immune cell function and leads to recurrent infections. However, immune dysregulation is not the defining feature of the syndrome, but rather a consequence of the WAS protein deficiency.
C. Autoimmune disease is not a defining feature of WAS. Instead, WAS is primarily characterized by immune dysregulation, recurrent infections, and bleeding disorders. Autoimmune disease is a possible consequence of WAS but not the primary disorder.
D. X-linked recessive inheritance is the correct answer. In WAS, males are more affected due to the X-linked pattern of inheritance.
**Clinical Pearls:**
Wiskott-Aldrich syndrome is an important differential diagnosis to consider in young male patients presenting with recurrent infections, eczema, and bleeding disorders. It is crucial to assess the family history and examine the patient for the typical features of WAS, such as microcephaly, atypical facies, and eczema. Early initiation of appropriate treatment, involving immune-modulating therapies, stem cell transplantation, or other supportive care, can improve the patient's prognosis.