Etiology

Hemoptysis, or coughing up blood, has a wide range of potential causes. These are typically classified based on the anatomical origin of the bleeding (airways, pulmonary vasculature, or lung parenchyma) or the underlying pathology. Here’s a breakdown:

1. Airway Causes

• Infections:
  • Bronchitis (acute or chronic)
  • Bronchiectasis
  • Tuberculosis
• Neoplasms:
  • Bronchogenic carcinoma
  • Endobronchial metastases
  • Benign tumors (e.g., hamartomas)
• Trauma:
  • Airway injury (e.g., from intubation, bronchoscopy, or foreign body)

2. Pulmonary Vasculature Causes

• Pulmonary Embolism: Often associated with infarction.
• Pulmonary Hypertension: Particularly in conditions like idiopathic pulmonary arterial hypertension or secondary to mitral stenosis.
• Vascular Malformations: Arteriovenous malformations (AVMs).
• Coagulopathies: Due to anticoagulant use, platelet disorders, or liver dysfunction.

3. Parenchymal Causes

• Infections:
  • Pneumonia (especially necrotizing or cavitary types)
  • Lung abscess
• Autoimmune Disorders:
  • Goodpasture’s syndrome
  • Granulomatosis with polyangiitis (Wegener’s)
• Interstitial Lung Diseases:
  • Diffuse alveolar hemorrhage syndromes

4. Cardiac Causes

• Mitral Stenosis: Causes elevated pulmonary venous pressure leading to hemoptysis.
• Congestive Heart Failure: Rarely associated but may cause pink, frothy sputum.

5. Iatrogenic Causes

• Procedures:
  • Bronchoscopy
  • Lung biopsy
• Medications:
  • Anticoagulants (e.g., warfarin, heparin)
  • Antiplatelet agents

6. Systemic Causes

• Hematologic Disorders:
  • Disseminated intravascular coagulation (DIC)
  • Thrombocytopenia
• Bleeding Disorders:
  • Hemophilia
  • Von Willebrand disease

7. Miscellaneous Causes

• Foreign Body Aspiration
• Environmental/Occupational Exposures: Such as silica or asbestos.
• Idiopathic: In some cases, no clear cause is identified.

Initial Assessment

Key factors in assessing hemoptysis include:

• Severity: Ranges from mild (streaks of blood) to massive (>200-600 mL in 24 hours).
• Duration: Acute versus chronic.
• Associated Symptoms: Fever, weight loss, chest pain, or shortness of breath.

Workup

The diagnostic approach may involve:

• Imaging: Chest X-ray, CT chest (with angiography if needed).
• Bronchoscopy: For localizing the source of bleeding.
• Laboratory Tests: CBC, coagulation studies, sputum culture, and cytology.

Understanding the etiology is critical for effective management, particularly in cases of life-threatening hemoptysis.

Hemoptysis
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