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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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A child present with recurrent episodes of sinopulmonary infection by bacteria with polysacharide rich capsule. Deficiency of which of the following immunoglobulin subclasses should be specifically investigated -
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The correct answer is  Ans. is 'd' i.e., IgA+IgG2 Primary Immunodeficiency Diseases, Defination, Diagnosis and Management . IgG2 dificiency is the most common subclass disorder associated with recurrent infections by polysaccharide-encapsulated bacteria. Such infections are more frequent in patients with associated IgA deficiency.