A 4-month-old infant in whom sudden death terminated a clinical picture which included conjunctivitis but was dominated by high fever, leukocytosis, and clinical signs and x-ray evidence of pneumonitis is reported along with autopsy findings. The pathologic findings were dominated by a productive, exudative, and thrombotic occlusive vasculitis involving principally the coronary arteries and their branches with a lesser degree of vasculitis and granulomatous inflammation of lungs and spleen. The clinical picture may have given a clue to the underlying pathology. Fienberg's term, "pathergic granulomatosis," may be appropriately applied to cases of this type until more is known of the etiology.