What is a common clinical presentation of IgA deficiency?

IgA deficiency is characterized by a quantitative deficiency of immunoglobulin A, which plays a vital role in mucosal immunity. Individuals with this deficiency often experience recurrent infections, particularly those affecting the mucosal surfaces, such as the respiratory and gastrointestinal tracts. Recurrent sinus infections are one manifestation of this condition, as IgA is crucial for the protection of mucous membranes.

People with IgA deficiency tend to have lower levels of mucosal immunity, making them more susceptible to infections in the sinuses and other areas where IgA is typically found. While frequent chest infections, increased allergic reactions, and autoimmune disorders can occur in individuals with various immune dysfunctions, they are not as specifically associated with IgA deficiency as recurrent sinus infections.

Therefore, the clinical presentation of recurrent sinus infections aligns well with the primary role of IgA in protecting mucosal areas, making it the correct answer in this context.