Hemoptysis

Hemoptysis, also spelled haemoptysis, is the coughing up or expulsion of blood or blood-stained mucus that originates from the airway, most often the bronchi, larynx, trachea, or lungs, and despite the common association with coughing it is airway bleeding that does not necessarily involve a cough at all. It can be caused by a wide range of underlying conditions, including lung cancer, infections such as tuberculosis, bronchitis, or pneumonia, and certain cardiovascular conditions. It is classified as massive once the volume reaches around three hundred milliliters, though different sources set the threshold anywhere from one hundred to six hundred milliliters, and when bleeding on that scale occurs it always reflects a severe underlying injury. The greatest danger from hemoptysis is not blood loss itself but choking, since blood in the airway can obstruct breathing, and pulmonary aspiration is a recognized complication; the symptom is generally managed within the specialty of pulmonology, which addresses both its diagnosis and treatment.