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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.
user
The commonest primary immunodeficiency is?
assistant
The correct answer is  Isolated IgA Deficiency: commonest immunodeficiency (1/600) Affected individuals have extremely low levels of both serum and secretory IgA C/F: asymptomatic, recurrent respiratory infections