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What is Diagnostic features of allergic bronchopulmonary aspergillosis (ABPA) include and explain in detail?
ABPA is a distinct diagnosis from simple asthma, characterized by prominent peripheral eosinophilia and elevated circulating levels of IgE (>417 IU/mL). Establishing a diagnosis of ABPA also requires establishing sensitivity to Aspergillus antigens by skin test reactivity, positive serum precipitins for Aspergillus, and/or direct measurement of circulating specific IgG and IgE to Aspergillus. Central bronchiectasis is described as a classic finding on chest imaging in ABPA but is not necessary for making a diagnosis. Other possible findings on chest imaging include patchy infiltrates and evidence of mucus impaction. Ref Harrison 19th edition pg 1686