Foci of organizing pneumonia are nonspecific and can occur secondary to other pathologic processes, including infections, vasculitis, lymphoma, and other interstitial lung diseases such as idiopathic pulmonary fibrosis, nonspecific interstitial pneumonia, connective tissue-related interstitial lung disease, drug-induced pulmonary disease, hypersensitivity pneumonitis, and chronic eosinophilic pneumonia.