A variety of processes can cause interstitial lung disease-like patterns but are not forms of ILD. These include fibrosis secondary to chronic alveolar hemorrhage, which most commonly is associated with underlying vasculitis, Kaposi sarcoma, some lymphomas, leukemias that involve the lung, and lymphangitic carcinoma. In addition, a lung that is collapsed or crushed can mimic ILD even though the parenchyma is completely normal.