Wegener's granulomatosis presenting with diffuse alveolar hemorrhage and negative antineutrophilic cytoplasmic antibody test.

One of the causes of diffuse pulmonary infiltrates can be blood from diffuse alveolar hemorrhage. Other causes include malignancy, edema fluid, infections, and protein (blood, pus, water, cells, or protein). Autoimmune vasculitis, such as Wegener's granulomatosis, should be considered in the setting of diffuse pulmonary infiltrates, anemia, systemic symptoms, and recurrence despite antibiotic therapy. Antineutrophilic cytoplasmic antibody testing can be useful but is not always diagnostic. Early tissue biopsy should be considered to guide therapy. We present a case of Wegener's granulomatosis that presented with diffuse alveolar hemorrhage. Diagnosis was made through renal biopsy; however, antineutrophilic cytoplasmic antibody testing was negative. A brief overview of pulmonary-renal vasculitides is also presented.