Which infection is associated with a high risk in patients with Bruton's agammaglobulinemia?

Bruton's agammaglobulinemia, also known as X-linked agammaglobulinemia, is a primary immunodeficiency characterized by the absence of functional B cells, leading to significantly reduced levels of immunoglobulins and an increased susceptibility to infections. In patients with this condition, antibody-mediated immunity is severely compromised.

Streptococcus pneumoniae is a encapsulated bacterium and one of the most common pathogens that causes serious infections in individuals with impaired humoral immunity. Because individuals with Bruton's agammaglobulinemia lack the ability to produce antibodies effectively, they are unable to mount an adequate immune response against encapsulated organisms like S. pneumoniae. This makes them particularly vulnerable to infections such as pneumonia, meningitis, and otitis media caused by this bacterium.

In contrast, the other options listed may not pose the same high risk in these patients. For example, while rotavirus and E. coli infections can occur, these pathogens do not primarily rely on antibody-mediated immunity for their pathogenicity in the same way that encapsulated organisms like S. pneumoniae do. Influenza virus can certainly cause significant morbidity, but the specific risk associated with the lack of antibodies in agammaglobulinem