ABSTRACT
Extrinsic allergic alveolitis (EAA) is synonymous with hypersensitivity pneumonitis and is a form of interstitial lung disease requiring previous sensitisation to an inhaled antigen. Although EAA is a commonly recognised form of interstitial lung disease (ILD), expert groups have found it challenging to produce a simple consensus denition for the condition (Girard et al., 2009).
