Features of pulmonary necrotizing sarcoid angiitis and granulomatosis:
(1) pulmonary vasculitis involving arteries and veins (angiitis) with intramural chronic inflammatory cells (lymphocytes, plasma cells) and/or granulomas
(2) non-necrotizing granulomas involving the lung parenchyma and the airways. These may be confluent and large enough to be seen on chest X-ray as pulmonary nodules.
(3) variable decrease in diffusion capacity (DLco)
(4) variable foci of parenchymal necrosis
(5) variable hilar lymphadenopathy
(6) absence of vasculitis outside of the lungs
(7) variable extrapulmonary symptoms
(8) exclusion of alternative diagnoses (systemic vasculitis, infectious granulomas, etc)
(9) excellent prognosis with either spontaneous resolution or response to corticosteroids
