Diffuse alveolar hemorrhage

Background

• Diffuse Alveolar Hemorrhage (DAH) is a life-threatening condition.
• It is a subset of Pulmonary hemorrhage involving the microcirculation involving alveolar microvasculature.
• Most commonly the result of systemic vasculitis.

Clinical Features

• Hemoptysis
• Anemia
• Diffuse lung infiltrates
• Acute respiratory failure

Differential Diagnosis

Idiopathic small vessel vasculitis

• Wegener's granulomatosis
• Churg-Straus syndrome
• Microscopic polyangitis

Primary immune complex-mediated vasculitis

• Goodpasture's syndrome
• Henoch-Schonlein purpura

Secondary vasculitis

• Systemic lupus erythematosus
• Rheumatoid arthritis
• Mixed connective tissue disease
• Polymyositis/Dermatomyositis

Acute lung transplant rejection

Drug induced (ie. chemotherapy, amiodarone, propylthiouracil)

ARDS

Coagulopathy

Pulmonic veno-occlusive disease

Mitral stenosis