Patients with Wiskott-Aldrich syndrome are particularly at risk for infections caused by which type of pathogens?

Wiskott-Aldrich syndrome is an X-linked immunodeficiency characterized by the triad of eczema, recurrent infections, and thrombocytopenia. The immune dysfunction observed in patients with this condition primarily affects their ability to mount proper antibody responses, particularly to polysaccharide capsules of bacteria.

Patients with Wiskott-Aldrich syndrome have a deficiency in their humoral immune response, which makes them particularly vulnerable to infections caused by encapsulated bacteria. These pathogens, such as Streptococcus pneumoniae and Haemophilus influenzae type b, are typically combated by antibodies that opsonize the capsule and facilitate phagocytosis. Children with Wiskott-Aldrich syndrome often have a reduced immune response to these encapsulated organisms, resulting in a higher incidence of infections.

Understanding the specific vulnerabilities in immune response helps in tailoring preventive strategies, such as vaccination against these encapsulated bacteria, to reduce infection risks in affected individuals.