This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Respiratory, Subject name: Medicine
[{'content': 'Allergic bronchopulmonary aspergillosis is (ABPA) usually diagnosed by A/E: \nSelect and explain. \nA. Peripheral blood eosinophilia > 0.5 x 1010, B. Sputum showing hyphae, C. Asthma, D. Elevated Ig E', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ans: A (Peripheral blood eosinophilia >0.5x1010) Ref: Harrison, 16th, ed. p. 1257; 17th, ed, p. 1259Definitive major and minor criterias are defined for allergic bronchopulmonary aspergillosis. Ig A is not present in these criteria.Major diagnostic criteria1. Clinical history of asthma2. Pulmonary infiltrates (transient or fixed)3. Peripheral eosinophilia (> 1000/uL)4. Immediate skin reactivity to aspergillus antigen.5. Serum precipitates to A. fiimigatus6. Elevated serum IgE levels.7. Central / proximal bronchiectasisSecondary diagnostic criteria1. History of brownish plugs in sputum2. Culture of A. fumigatus from sputum3. Late skin reactivity to aspergillus antigen4. Elevated IgE (and IgG) class antibodies specific for A. fumigatus.', 'role': 'assistant'}]