Hemoptysis: Evaluation and Management.

Hemoptysis is the expectoration of blood from the lower respiratory tract, usually from bronchial arteries. The most common causes are acute respiratory infections, cancer, bronchiectasis, and chronic obstructive pulmonary disease. No cause is identified in 20% to 50% of cases. Hemoptysis must be differentiated from pseudohemoptysis, which is blood that originates from nasopharyngeal or gastrointestinal sources. The initial evaluation includes...