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Hemoptysis & Diffuse Alveolar Hemorrhage

Name: Hemoptysis & Diffuse Alveolar Hemorrhage
Creator: Veli Bakalov, MD

Protect the good lung, embolize the bronchial artery, and catch the bleed that is never coughed up

Pulmonology·Pulmonary Diagnostics & Symptom Approach·6 min read·8 high-yield points·Reviewed by Veli Bakalov, MD @HemeOncBuddy

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Confirm a pulmonary source first: hemoptysis is bright red, frothy, alkaline and mixed with sputum; hematemesis is dark, acidic and contains food.
Acute bronchitis is the most common cause of hemoptysis; bronchiectasis, lung cancer, TB, aspergilloma, PE, mitral stenosis, anticoagulation and HHT AVMs are the key others.
Nonmassive hemoptysis: chest x-ray first, then CT chest; bronchoscopy for smokers older than 40, abnormal imaging or persistent bleeding.
Massive hemoptysis kills by asphyxiation: intubate with a large-bore tube (≥8.0) and position the patient bleeding side down.
Bronchial arteries cause about 90% of massive bleeds: stabilize, CT angiography, then bronchial artery embolization; rigid bronchoscopy or surgery if refractory.
HHT (ENG, ACVRL1) pulmonary AVMs cause right-to-left shunting with paradoxical stroke and brain abscess; screen with bubble echo and embolize.
Diffuse alveolar hemorrhage: falling hemoglobin plus bilateral infiltrates, hemoptysis absent in up to one-third, rising DLCO, bloodier serial BAL aliquots, hemosiderin-laden macrophages.
DAH causes: GPA, MPA, anti-GBM disease, SLE, crack cocaine, post-HSCT; treat immune DAH with pulse steroids plus cyclophosphamide or rituximab, adding plasma exchange for anti-GBM disease.

Confirming the source and sorting the causes

Definition. Hemoptysis is expectoration of blood that originates below the vocal cords. First confirm a lower respiratory source: posterior epistaxis or upper GI bleeding can be swallowed or aspirated and then coughed up (pseudohemoptysis), so examine the nose and oropharynx in every patient.

Where is the blood coming from?

Feature	Hemoptysis	Hematemesis	Nasopharyngeal bleeding
Setting	Cough; lung disease history	Nausea, vomiting; ulcer or liver disease	Epistaxis, blood trickling down the throat
Appearance	Bright red, frothy, mixed with sputum	Dark red or coffee-ground, may contain food	Bright red, little sputum
pH / contents	Alkaline; alveolar macrophages and neutrophils	Acidic; gastric contents	Variable

Airway causes. Acute bronchitis is the most common cause of hemoptysis, usually small streaks that resolve with the infection. Bronchiectasis produces recurrent and sometimes massive bleeding from hypertrophied bronchial arteries. Central tumors, particularly squamous cell carcinoma and the highly vascular bronchial carcinoid, bleed from the airway wall; age over 40 and a smoking history raise the probability of cancer.

Parenchymal causes. Reactivation tuberculosis (upper-lobe cavity, fevers, night sweats, weight loss) can erode a vessel; a Rasmussen aneurysm is a pulmonary artery pseudoaneurysm in the wall of a TB cavity. An aspergilloma is a fungus ball colonizing a preexisting cavity (old TB, sarcoidosis), seen as a mobile mass with an air crescent (unlike invasive aspergillosis, which invades tissue in neutropenic hosts); it can bleed massively, antifungals do little, and significant bleeding is an indication for resection. Pneumonia and lung abscess are other parenchymal sources.

Vascular causes. Pulmonary embolism with infarction causes pleuritic pain, tachycardia, and small-volume hemoptysis, sometimes with a wedge-shaped pleural-based opacity (Hampton hump). In mitral stenosis, high left atrial and pulmonary venous pressures dilate and rupture bronchial veins. Hereditary hemorrhagic telangiectasia (Osler-Weber-Rendu; autosomal dominant, ENG or ACVRL1, and SMAD4 with juvenile polyposis) causes recurrent epistaxis, mucocutaneous telangiectasias, and pulmonary arteriovenous malformations. The AVM is a right-to-left shunt, producing hypoxemia, paradoxical embolic stroke, and brain abscess; screen family members with a contrast (bubble) echocardiogram and treat AVMs with sizable feeding arteries by transcatheter embolization.

Systemic causes. Coagulopathy, thrombocytopenia, and anticoagulants promote bleeding, but hemoptysis at a therapeutic INR usually signals a structural lesion that still needs imaging.

Evaluating nonmassive hemoptysis

History. Estimate volume and duration; ask about smoking, weight loss, TB risk, anticoagulants, and vasculitis features (sinusitis, hematuria, rash).

Confirm the sourceExclude upper GI and nasopharyngeal bleeding.
Chest radiographThe initial test for every patient; may show a mass, cavity, infiltrate, or bronchiectasis.
Laboratory testsCBC, PT/INR, PTT, creatinine, and urinalysis (dysmorphic RBCs or RBC casts suggest a pulmonary-renal syndrome); three sputum specimens for AFB smear, culture, and NAAT, with airborne isolation, if TB is possible.
CT chestFor an abnormal film, smokers or patients older than 40, or recurrent bleeding. CT identifies more causes (bronchiectasis, small tumors) than bronchoscopy.
BronchoscopyFor smokers older than 40, abnormal imaging, or persistent bleeding: direct view of central airways, biopsy, and washings.

A normal chest x-ray does not exclude lung cancer in an older smoker. Conversely, a young nonsmoker with bronchitis symptoms, small-volume streaking, and a normal film can be treated and observed.

Massive hemoptysis

100–600 mLrange of 24-hour volumes used to define massive hemoptysis

~150 mLanatomic dead space of the conducting airways

~90%of massive bleeds arise from bronchial arteries

Definition. There is no single volume cutoff. Any bleeding that compromises the airway, causes hypoxemia, or destabilizes hemodynamics should be managed as massive. Patients die of asphyxiation rather than exsanguination because a small volume of blood can flood the conducting airways.

Airway and positioning. Intubate early with a large-bore endotracheal tube (8.0 or larger) that admits a therapeutic bronchoscope. Place the patient in the lateral decubitus position with the bleeding side down so blood stays in the diseased lung. If the good lung is being flooded, isolate it: mainstem intubation of the non-bleeding lung (ideally over a bronchoscope), a double-lumen tube, or an endobronchial blocker.

Resuscitation. Transfuse as needed, correct thrombocytopenia and coagulopathy, and reverse anticoagulants: warfarin with 4-factor prothrombin complex concentrate plus IV vitamin K; dabigatran with idarucizumab (an antibody fragment that binds the drug); apixaban or rivaroxaban with 4-factor PCC (andexanet alfa was withdrawn from the US market in December 2025).

Localization and definitive control. The bronchial arteries, which arise from the aorta at systemic pressure, are the usual source; pulmonary arteries bleed in a minority (Rasmussen aneurysm, catheter injury, AVM). Once the patient is stabilized, CT angiography localizes the site and maps feeding vessels, and bronchial artery embolization is first-line definitive therapy. Bronchoscopy localizes the side and allows temporizing iced saline, topical epinephrine, or balloon tamponade; rigid bronchoscopy adds large-channel suction and airway control. Surgery is reserved for bleeding refractory to embolization or localized lesions such as an aspergilloma or trauma.

Do not send a patient with an unsecured airway and ongoing massive bleeding to the CT scanner. A rare but classic complication of bronchial artery embolization is spinal cord ischemia, when a spinal artery arises from the embolized bronchial-intercostal trunk.

Diffuse alveolar hemorrhage

Presentation. Diffuse alveolar hemorrhage (DAH) is bleeding from the alveolar capillaries throughout both lungs. It presents with dyspnea, hypoxemic respiratory failure, a falling hemoglobin, and new bilateral ground-glass or alveolar infiltrates. Hemoptysis is absent in up to one-third of patients, so the diagnosis must be suspected from anemia plus infiltrates, especially with renal involvement.

Physiology and testing. Hemoglobin in the alveoli takes up carbon monoxide, so the DLCO rises (otherwise elevated mainly with polycythemia, asthma, obesity, and left-to-right shunts), although it is rarely measurable in a critically ill patient. Bronchoalveolar lavage confirms the diagnosis: sequential aliquots return progressively bloodier fluid, whereas a proximal airway bleed clears with each aliquot. Hemosiderin-laden macrophages (Prussian blue stain) appear about 48–72 hours after bleeding; 20% or more supports DAH. BAL also excludes infection, the main mimic in immunocompromised patients.

Etiology workup. Send ANCA (PR3 and MPO), anti-GBM antibodies, ANA, anti-dsDNA, complement, creatinine, and urinalysis; kidney biopsy is often easier than lung biopsy. Immune causes typically show pulmonary capillaritis.

Major causes of diffuse alveolar hemorrhage

Cause	Clues	Treatment
Granulomatosis with polyangiitis	PR3-ANCA; sinusitis, nasal crusting, cavitary nodules, glomerulonephritis	Pulse steroids plus rituximab or cyclophosphamide
Microscopic polyangiitis	MPO-ANCA; glomerulonephritis without granulomas	Pulse steroids plus rituximab or cyclophosphamide
Anti-GBM disease	Anti-GBM antibodies, linear IgG on biopsy; lung bleeding more common in smokers	Plasma exchange plus steroids and cyclophosphamide
Systemic lupus erythematosus	ANA, anti-dsDNA, low complement	Pulse steroids plus cyclophosphamide or rituximab
Crack cocaine	Inhalational injury shortly after use	Stop exposure; supportive care
Post-HSCT	Around engraftment; infection excluded on BAL	High-dose steroids; poor prognosis
Bland hemorrhage	Mitral stenosis, anticoagulants, thrombocytopenia	Correct the underlying problem

Treatment. Support oxygenation, transfuse, and correct coagulopathy. Immune DAH gets pulse IV methylprednisolone (up to 1 g daily for about 3 days) plus cyclophosphamide or rituximab. Plasma exchange removes circulating antibody and is standard for anti-GBM disease; its role in ANCA-associated DAH is debated. Bronchial artery embolization has no role, because diffuse capillary bleeding has no single feeding vessel.