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Diffuse Alveolar Hemorrhage

By

Joyce Lee

, MD, MAS, University of Colorado School of Medicine

Last full review/revision Sep 2021| Content last modified Sep 2021
Click here for the Professional Version
  • Common symptoms are difficulty breathing and coughing, often coughing up blood.

  • People usually have a chest x-ray, blood tests, and sometimes examination of the breathing passages with a flexible viewing tube (bronchoscopy).

  • Treatment of autoimmune causes involves suppression of the immune system with corticosteroids and often cyclophosphamide (a chemotherapy drug) or rituximab (a type of immune suppression drug).

An important function of the immune system Overview of the Immune System The immune system is designed to defend the body against foreign or dangerous invaders. Such invaders include Microorganisms (commonly called germs, such as bacteria, viruses, and fungi) Parasites... read more is fighting off infections. To do this, the immune system recognizes microorganisms as foreign to the person and produces proteins (antibodies Antibodies One of the body's lines of defense (immune system) involves white blood cells (leukocytes) that travel through the bloodstream and into tissues, searching for and attacking microorganisms and... read more Antibodies ) that join with the microorganisms so they can be removed from the body. In autoimmune disorders Autoimmune Disorders An autoimmune disorder is a malfunction of the body's immune system that causes the body to attack its own tissues. What triggers autoimmune disorders is not known. Symptoms vary depending on... read more , the body mistakenly reacts against a person's own tissues as if they were foreign. In autoimmune disorders that involve the lungs, the immune system attacks and damages lung tissue. Autoimmune disorders that affect the lungs also often affect other organs, particularly the kidneys.

Diffuse alveolar hemorrhage is a syndrome, not a particular disorder. A syndrome is a group of symptoms and other abnormalities that occur together but may be caused by several different disorders. Diffuse alveolar hemorrhage involves damage to the small blood vessels that supply the lungs, causing blood to accumulate in the tiny air sacs (alveoli) of the lungs. Such blood vessel damage can result from several disorders.

Causes of Diffuse Alveolar Hemorrhage

Many disorders can cause diffuse alveolar hemorrhage.

The most common causes are

Other disorders that can cause diffuse alveolar hemorrhage include

Symptoms of Diffuse Alveolar Hemorrhage

Diffuse alveolar hemorrhage syndrome can cause

  • Cough

  • Difficulty breathing

  • Fever

When the disorder is severe, breathing may be extremely difficult. People may gasp and have bluish discoloration of the skin (cyanosis). At least two thirds of all people with diffuse alveolar hemorrhage cough up blood. Some people die.

People may also have other symptoms typical of the disorder that caused the diffuse alveolar hemorrhage.

Diagnosis of Diffuse Alveolar Hemorrhage

  • Computed tomography scan of chest

  • Sometimes insertion of a flexible viewing tube into the lungs (bronchoscopy) with fluid wash out (bronchoalveolar lavage)

Doctors can often diagnose diffuse alveolar hemorrhage by a person's symptoms and chest imaging findings. Chest imaging typically show abnormal white patches in the lungs caused by lung bleeding. If the diagnosis is not clear based on symptoms and chest imaging findings (for example, if the person has not coughed up blood), doctors may need to insert a flexible viewing tube into the lungs (bronchoscopy Bronchoscopy Bronchoscopy is a direct visual examination of the voice box (larynx) and airways through a viewing tube (a bronchoscope). A bronchoscope has a camera at the end that allows a doctor to look... read more Bronchoscopy ) and wash out the lungs with fluid (bronchoalveolar lavage Procedures Done With Bronchoscopy Bronchoscopy is a direct visual examination of the voice box (larynx) and airways through a viewing tube (a bronchoscope). A bronchoscope has a camera at the end that allows a doctor to look... read more Procedures Done With Bronchoscopy ) to check for small amounts of blood.

The level of red cells in the blood is measured to test for anemia.

After diffuse alveolar hemorrhage has been diagnosed, the cause must be determined. A variety of blood tests may be done, depending on what disorders seem to be likely causes. Urinalysis is done to tell whether the person has kidney damage, characteristic of the pulmonary-renal syndrome Pulmonary-Renal Syndrome Pulmonary-renal syndrome combines both diffuse alveolar hemorrhage (recurrent or persistent bleeding into the lungs) and glomerulonephritis (damage to the microscopic blood vessels in the kidneys... read more .

Treatment of Diffuse Alveolar Hemorrhage

  • Treat specific cause of disorder

  • Sometimes corticosteroids, cyclophosphamide, or rituximab

  • Supportive measures

The disorder causing diffuse alveolar hemorrhage is treated.

Autoimmune disorders are commonly treated with corticosteroids (such as prednisone) and sometimes cyclophosphamide (a chemotherapy drug) or other drugs (such as rituximab) that suppress the immune system.

Problems that people with diffuse alveolar hemorrhage also have, such as difficulty breathing and clotting disorders, are also treated. For example, people may be given oxygen or may need to be on a ventilator Mechanical Ventilation Mechanical ventilation is use of a machine to aid the movement of air into and out of the lungs. Some people with respiratory failure need a mechanical ventilator (a machine that helps air get... read more for a period of time.

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Coughing Up Blood
Coughing up blood from the respiratory tract is called hemoptysis. Which of the following is the most likely cause of hemoptysis in adults?
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