Conditions associated with organising pneumonia (OP)#
| Connective tissue disorders |
| Hypersensitivity pneumonitis (acute) |
| Adverse drug reactions |
| Bone marrow, stem cell or solid organ transplantation |
| Infection |
| Airway diseases complicated by infection |
| Airway obstruction (distal changes) |
| Inhalation injury |
| Aspiration syndromes |
| Chronic eosinophilic pneumonia |
| Radiation pneumonitis |
| Inflammatory bowel disease |
| Neoplasms and myeloproliferative disorders |
| Organising diffuse alveolar damage |
| Coexistent with pathologic changes of IIP (e.g. UIP or NSIP) |
| Acute exacerbation of IPF (OP lesions superimposed on chronic UIP pattern) |
| Proximal bronchial obstruction (OP found distal to focus of obstruction) |
| Miscellaneous |
| Immunodeficiency syndromes |
| Cryoglobulinemia |
| Granulomatosis with polyangiitis |
| Other vasculitis |
IIP: idiopathic interstitial pneumonia; UIP: usual interstitial pneumonia; NSIP: nonspecific interstitial pneumonia; IPF: idiopathic pulmonary fibrosis. #: conditions other than cryptogenic organising pneumonia (idiopathic OP) that have been associated with histopathologic findings of OP in lung tissue specimens.