acute extrinsic allergic alveolitis - investigations

Last reviewed 01/2018

The investigation of acute extrinsic allergic alveolitis should include:

• FBC shows neutrophilia with raised or normal eosinophils
• ESR is raised
• blood gases show hypoxaemia
• serum precipitins are present
• chest radiography shows a variable appearance, including ground-glass or nodules
• lung function tests demonstrate a transient, slight reduction in lung volume and a transient reduction in transfer factor
• bronchoalveolar lavage shows a predominance of mast cells and lymphocytes
• provocation test with suspected antigen if the history is unclear
• transbronchial or open lung biopsy if the diagnosis is in doubt