Etiologies and Evaluation of Hemoptysis

Common Causes

The American College of Radiology suggests that bronchiectasis is the leading cause of hemoptysis in most tertiary referral centers, followed by chronic bronchitis, lung cancer, and respiratory tract infections 1, 2, 3
Bronchiectasis accounts for the majority of cases in large studies, particularly in patients with chronic inflammatory conditions, cystic fibrosis, or prior tuberculosis 1, 2
Chronic bronchitis and acute respiratory infections are common causes, with acute bronchitis representing up to 63% of mild hemoptysis cases 3
Lung cancer is the second most common cause in patients with hemoptysis and normal chest radiographs, and should be strongly suspected in patients with occupational carcinogen exposure 3
Tuberculosis and nontuberculous mycobacterium remain significant causes, with nontuberculous mycobacterium accounting for 24% of cases in some series 3
Pulmonary aspergillomas frequently develop in pre-existing cavities from tuberculosis and cause recurrent hemoptysis with high recurrence rates of 55% 1, 2

Bacterial pneumonia is particularly common in immunocompromised patients, including those with chronic kidney disease on hemodialysis 4
Active tuberculosis remains a major cause globally and should be considered in endemic areas or high-risk populations 3
Fungal infections, particularly aspergillomas in pre-existing cavities, cause both acute and recurrent bleeding 1, 2

Bronchogenic carcinoma presents with hemoptysis in >65% of cases, particularly with centrally-located tumors that stimulate cough receptors 5
Metastatic disease to the lungs can cause hemoptysis, though less commonly than primary lung cancer 4
Even small amounts of blood-streaked sputum should raise concern for endobronchial tumor in patients with risk factors such as smoking or occupational exposures 5

Pulmonary arteriovenous malformations can cause significant bleeding and require embolization 4
Pulmonary artery aneurysms and pseudoaneurysms are potential sources, particularly in patients with chronic inflammatory disease 4
Mitral stenosis causes hemoptysis through chronic pulmonary venous hypertension, presenting with classic radiographic findings of elevated left main bronchus and parahilar interstitial infiltrates 6

Immune-complex mediated diseases such as HCV-associated glomerulonephritis can cause pulmonary-renal syndromes with hemoptysis 4
Sarcoidosis with advanced pulmonary disease causes hemoptysis that typically requires palliative treatment, as these patients are often not surgical candidates 1, 2

No identifiable cause is found in 20-34% of cases despite complete evaluation, though these patients often respond well to bronchial artery embolization with 97% remaining free of hemoptysis at 20 months 3

In chronic kidney disease patients on hemodialysis, respiratory tract infections are more common due to immunocompromised state 4
In postpartum women, mitral stenosis should be considered, as pregnancy increases cardiac output and can precipitate pulmonary hypertension with hemoptysis 6

The American College of Radiology notes that the most common causes of hemoptysis vary by geographic location and clinical setting, with tuberculosis and its sequelae remaining the leading cause in developing countries, while bronchiectasis, respiratory infections, and lung carcinomas are most common in tertiary referral centers in North America and Europe 7, 8

Sarcoidosis with advanced pulmonary disease can cause hemoptysis that typically requires palliative treatment, as these patients are often not surgical candidates, according to the American College of Radiology 7, 8
Autoimmune diseases resulting in capillaritis or cavitation, including immune-complex mediated diseases, can cause pulmonary-renal syndromes with hemoptysis, as reported by the American College of Radiology 7, 8
Coagulopathies are additional causes of hemoptysis to consider, as noted by the American College of Radiology 7

Pulmonary embolus is an uncommon cause of hemoptysis, with only a single study reporting it as one of the primary causes, according to the American College of Radiology 7

No identifiable cause is found in approximately 20% of patients initially presenting with hemoptysis despite extensive investigation by both CT and bronchoscopy, as reported by the American College of Radiology 7, 8
Cryptogenic hemoptysis has been reported as high as 50%, though this upper range is likely inflated because of incomplete investigation with either CT or bronchoscopy, according to the American College of Radiology 7