oughing blood also known as hemoptysis, can be a sign of a severe medical condition such as cancer, infections, problems in blood vessels or in the lungs. Coughing up blood generally requires medical evaluation unless the hemoptysis is caused by bronchitis.

Causes of Hemoptysis

There are many potential reasons for coughing up blood. Causes for coughing blood include:

Bronchitis(acute or chronic), the most common cause of coughing up blood. Hemoptysis due to bronchitis isn’t life-threatening.
Bronchiectasis
Lung cancer or non-malignant lung tumours
Use of blood thinners
Pneumonia
Pulmonary embolism
Congestive heart failure especially due to mitral stenosis
Tuberculosis
Inflammatory or autoimmune conditions (lupus, Wegener’s granulomatosis, microscopic polyangiitis, Churg-Strauss syndrome, and many others)
Pulmonary arteriovenous malformations (AVMs)
Crack cocaine
Trauma, such as a gunshot wound or motor vehicle accident
Dieulafoy’s disease
Hemoptysis can also come from bleeding outside the lungs and airways. Severe nosebleeds or vomiting of blood from the stomach can result in blood draining into the windpipe or trachea. The blood is then coughed up, appearing as hemoptysis.

In many people with hemoptysis, no cause is ever identified. Most people with mysterious hemoptysis are no longer coughing up blood after six months.

Hemoptysis Tests

In people who are coughing up blood, testing focuses on determining the rate of bleeding and any risk to breathing. The cause for hemoptysis must then be identified. Tests for coughing up blood include:

History and physical examination: By talking to and examining someone who is coughing up blood, a doctor gathers clues that help identify the cause.

Chest X-ray: This test may show a mass in the chest, areas of fluid or congestion in the lungs, or it can be normal.

Computed tomography (CT scan): A CT scan can reveal some causes for coughing up blood by producing detailed images of structures in the chest.

Bronchoscopy: For this test, the doctor uses an endoscope (A flexible tube with a camera on its end). The endoscope is passed through the nose or mouth into the windpipe and airways to identify the cause of hemoptysis.

Complete blood count(CBC): A test of the number of white and red blood cells in the blood, along with platelets (cells that help blood clot).

Urinalysis: Certain causes of hemoptysis also result in abnormalities on this simple urine test.

Coagulation tests: Changes in blood’s ability to clot can cause bleeding and coughing up blood.

Arterial blood gas: A test of the levels of oxygen and carbon dioxide in the blood. Oxygen levels can be low in people coughing up blood.

Pulse oximetry: In this test, a probe (usually on a finger) tests the level of oxygen in the blood.

Treatments for Hemoptysis

For people who are coughing up blood, treatments are targeted at stopping the bleeding, as well as treating the original cause of hemoptysis. Treatments include:

Bronchial artery embolization. A doctor advances a catheter through the leg into an artery supplying blood to the lungs. By injecting dye and viewing the arteries on a video screen, the doctor identifies the source of bleeding. That artery is then blocked, using metal coils or another substance. Bleeding usually stops, and other arteries compensate for the newly blocked artery.

Surgery. Coughing up blood, if severe and life-threatening, may require surgery to remove a lung (pneumonectomy).

Bronchoscopy. Tools on the end of the endoscope can be used to treat some causes of coughing up blood. For example, a balloon inflated inside the airway may help stop bleeding.

Treatments for hemoptysis should also address the underlying reason for coughing up blood. Other treatments for people coughing blood may include:

Antibiotics for pneumonia or tuberculosis
Chemotherapy and/ for lung cancer
Steroids for inflammatory conditions
When to See a Doctor

The most common reason for coughing up blood is acute bronchitis, which typically gets better on its own without medication. People with bronchitis with small amounts of blood in the mucus for less than a week can watch carefully and wait for their condition to improve. Call your doctor if you have any of these symptoms:

Blood in mucus that lasts longer than a week, is severe or getting worse, or comes and goes over time
Chest pain
Weight loss
Soaking sweats at night
Shortness of breath with your usual activity level
Fever higher than 101 degrees
SOURCE: http://www.healthdiary365.com/2017/11/15/coughing-up-blood-hemoptysis-causes-tests-and-treatment/