Haemoptysis is best described as “coughed up blood”. Often haemoptysis is not a disease itself but can signify a variety of underlying problems and should therefore be properly assessed by a doctor. Blood can manifest in many different forms, however often it is frothy and bright red.
The amount can be as minimal as blood stains in the spit (sputum) to more obvious larger amounts of blood or clots that would need a more immediate attention of a doctor. Amounts larger than 600ml are usually regarded as massive haemoptysis and do require emergency medical attention.
Haemoptysis should not be confused with haematemesis – which describes the vomiting of blood and, unlike haemoptysis, is often associated with nausea and vomiting as well as food particles that can be seen. The colour of the blood can range from bright red to dark, almost black dotted (“coffee ground” like) and should be best assessed by a physician as well.
The lungs, which are situated in the chest with the heart sitting between the right and the left lung lobe, usually get their blood supply from 2 different sources.
Most of the blood (95%) comes from the low-pressure pulmonary arteries and ends up in the pulmonary capillary bed, where gas is exchanged. A small portion (about 5%) of the blood supply circulates via high-pressure bronchial arteries, which come from the aorta and supply the structures of the major airways with blood.
In most cases of haemoptysis the blood originates from the pulmonary capillary bed (low pressure) and only in more rare cases (e.g. due to trauma or injury) from the high-pressure bronchial arteries.
If large volumes of blood enter the airway there is a risk of drowning and massive haemoptysis may result in severe anaemia, both of which are life threatening.
The reasons for haemoptysis can vary widely, common causes of haemoptysis include:
a. Infection: An infection of the main airways (called bronchitis) and the lung tissue (called pneumonia) are perhaps the most common (approximately 70%) causes of mild episodes of haemoptysis. Often other symptoms such as fatigue, fever or even shortness of breath are present as well. Usually with treating the underlying infection, the haemoptysis will disappear as well. Another typical cause of haemoptysis is still tuberculosis, which can present with night sweats and loss of weight.
b. Cancer: Cancer of the lung can develop from the cells lining the bronchi (airways). One of the earliest symptoms of lung cancer can be the coughing of blood; in fact, it can be the first symptom before others develop. Usually lung cancer develops in people above the age of 50 and who are smokers or have had a history of smoking or passive smoking. There are also other types of lung cancer that can develop in younger, non-smoking patients.
c. Bronchiectasis: One or more airways are unusually widened. This can lead to an extra production of mucous that collects in these areas – which explains the main symptom of a recurrent cough with large amounts of phlegm. These widened airways have a preponderance of getting infected, which can result in blood being mixed in the phlegm.
d. Inhalation of foreign bodies: The inhalation of small objects such as peanuts or small toy parts can cause injury and bleeding from the airways. This can frequently happen in children and when suspected, should be addressed by a pediatrician (doctor specialising in children care).
e. Pulmonary embolism: A pulmonary embolism is a blood clot blocking the main blood vessels of the lung. This is a potentially life-threatening condition that can present with (severe) breathlessness, chest pain and haemoptysis.
f. Heart failure: Severe heart failure can lead to a build-up of fluids in the lungs and which, besides breathlessness, can also lead to blood stains in the sputum – which often is frothy.
g. Inflammation and abnormal tissue deposits: Usually these are much more rare conditions, which may not only affect the lung tissue but can lead to abnormal tissue deposits in a variety of organs. Sometimes these inflammatory lesions and tissue deposits can lead to bleeding which then causes hemoptysis. Some conditions that would fall under this category would be Wegener’s granulomatosis, Goodpasture’s syndrome, lupus pneumonitis or endometriosis.
h. No cause identified: Some patients (about 5%) may fall under this category, where no clear cause can be established even when all necessary investigations have been performed.
Ideally, all patients presenting with haemoptysis should undergo further tests to rule out any underlying sinister causes. Besides the routine physical examination, your doctor will order a chest x-ray as a first assessment. If that is normal, further investigations might be necessary such as a computed tomography (CT) of the chest. Often a bronchoscopy – an endoscopic examination of the airways – is performed to identify a source of the bleeding or to even get a tissue biopsy from suspicious lesions.
Besides these, your doctor might order an electrocardiogram (ECG) or echocardiogram (Echo) if a heart problem or a pulmonary embolism is suspected.
Other tests such as sputum analysis and culture, full blood count and tests of the blood clotting ability might be ordered. In unclear cases more sophisticated tests such as CT angiograms (CT to show specific blood vessels) or even Positron Emission Tomography/CT (PET or PET/CT) may be ordered to further investigate.
Depending on the underlying cause of the haemoptysis the treatment might range from observation and antibiotic treatment to more invasive treatment such as bronchoscopy or open surgery.