Acute respiratory failure as primary manifestation of antineutrophil cytoplasmic antibodies-associated vasculitis.

The systemic vasculitides are multifocal diseases characterized by the presence of blood vessel inflammation in multiple organ systems. Their clinical presentation is variable extending from self-limited illness to critical complications including diffuse alveolar hemorrhage and glomerulonephritis. Alveolar hemorrhage is a life-threatening manifestation of pulmonary vasculitis that can rapidly progress into acute respiratory failure requiring ventilatory support. We present the case of a 74-year-old patient admitted to the Intensive Care Unit with severe hypoxic respiratory failure and diffuse alveolar infiltrates in chest imaging that was later diagnosed as antineutrophil cytoplasmic antibodies-associated vasculitis. The report highlights the importance of differentiate between alveolar hemorrhage and acute respiratory distress syndrome of other etiology because alveolar hemorrhage is reversible with prompt initiation of treatment.