Coughing Up Blood – COVID 19

Introduction

COVID-19, also known as coronavirus, is a viral infection that affects the respiratory system. The virus was first detected in China in late 2019 and was the cause of a global pandemic beginning in 2020.¹  As of September 2022, over 6.5 million people have died from coronavirus infections.² Cases are still widespread, though thankfully, death rates are falling, and vaccines are now widely available to protect against more severe infections.³ However, long COVID – persistent symptoms even after the initial infection – is a growing concern.⁴ Also, less common symptoms of COVID-19, such as coughing up blood (also known as haemoptysis), are not fully understood.

COVID-19 

Symptoms of COVID-19 

Part of the reason for this lack of understanding is that COVID-19 symptoms are varied and non-specific.⁵ The most commonly reported symptoms are a dry, persistent cough, fever and fatigue; however, other symptoms include: a loss of sense of smell or taste, shortness of breath, diarrhoea, headache, sore throat, nausea and blocked/runny nose.^{5, 6} This can make it difficult to diagnose the virus without a test, particularly as many patients are asymptomatic (they have no symptoms at all).¹

This is a serious issue, as severe COVID-19 infection can be fatal. People aged over 65 are particularly at risk, as well as those suffering from chronic health conditions such as diabetes, respiratory diseases, dementia, heart disease or asthma.⁷ Severe infection can also lead to a number of serious long-term medical complications such as pneumonia, heart disease, kidney disease, blood clots and acute respiratory distress syndrome.¹

As the death rates of COVID-19 fall, long COVID is becoming more of a focus for study. Typically, people who become infected with coronavirus feel better after a few days, and most have recovered by 12 days; in long COVID, however, symptoms persist for longer. This new condition affects 10% of people infected with the virus.⁴ Fatigue, shortness of breath, muscle and joint pain, altered smell and taste, and persistent cough are the most common symptoms.⁸

Is coughing up blood a symptom of COVID-19?

Haemoptysis (coughing up blood) is defined as spitting blood from the throat and lower airways. The blood can appear red or rust-coloured and may be mixed with mucus or air.⁹ Coughing up blood can be a symptom of serious disease, but it is important to note that this is not always the case. Breathlessness, changes in blood pressure, low oxygenation (hypoxia) and the amount of blood loss are included in factors that determine how serious this symptom is considered to be.⁹

Some patients with COVID-19 have reported coughing up blood as a symptom. One unusual case study involved a man who came into emergency care with severe haemoptysis and was discovered to have COVID-19, despite no other typical COVID-19 symptoms. Coughing up blood is rarely the first presentation of the virus; however, it is important to be aware of to understand the severity as this case of haemoptysis was life-threatening.⁶ A few other case studies have also reported haemoptysis as the first presentation of COVID-19, all in patients with another severe disease or active smokers.¹⁰

Another study discussed a man with moderate haemoptysis who had been infected with COVID-19 two months prior to this symptom appearing. The man had felt weak and tired, but there were no other symptoms of long COVID. Unlike the cases mentioned above, this man was not a smoker and had no relevant medical history.¹⁰

Evidence of haemoptysis as a symptom of COVID-19 has also been found through scientific research.⁹ In one study, which analysed data from a large number of other research works, the average prevalence of haemoptysis was 3.3% of patients with COVID-19.¹¹ Whilst this symptom is rare, is it not unheard of, and further study into cases of coughing up blood with COVID-19 will only contribute to our understanding of the virus itself.

Why do some people cough up blood with COVID-19?

Haemoptysis in COVID-19 is likely due to lung damage caused by infection, such as injury to endothelial cells (the membrane that lines blood vessels) and the presence of microthrombi (blood clots).^{9, 10}

Violent coughing caused by a COVID-19 infection may also irritate the throat and cause airway inflammation, resulting in haemoptysis. In this case, cough suppressant drugs may be given by a doctor, as well as other advice to manage violent coughing. They may also ask that the patient keeps track of how much blood they cough up and for how long this occurs.⁹ Massive amounts of bleeding have been treated with vasoconstrictive agents, which narrow the blood vessels to prevent further bleeding.¹⁰

Other causes for coughing up blood

Coughing up blood can occur with a variety of conditions, diseases, medications or medical tests.⁹ The most common causes of haemoptysis are malignant tumours (lung cancer), acute bronchitis, bronchiectasis (a condition where the airways of the lungs widen and excess mucus builds up, making the lungs vulnerable to infection)¹² and pneumonia (inflammation/swelling of lung tissue).¹³

Less common causes include pulmonary embolism (where a blood clot gets stuck in an artery of the lung, blocking blood flow to that part of the lung), vasculitis (inflammation of blood vessels), coagulation disorders (which affect the clotting ability of the blood) and arteriovenous malformations (where a group of blood vessels form incorrectly).⁶ Blood thinner drugs, tuberculosis, bronchoscopies and violent coughing that irritates the throat can also lead to haemoptysis.⁹

Measures can be taken to limit the effects of some of these causes. For example, a person’s risk of pulmonary embolism or vasculitis can be decreased by quitting smoking, getting regular exercise and not sitting down for too long.¹⁴ The risk of developing bronchitis can be reduced by avoiding breathing in irritants such as tobacco smoke or household chemicals.¹⁵ 

When to seek medical attention 

Of course, viral and bacterial infections are harder to avoid, and blood thinner drugs and bronchoscopies are essential. Often there is nothing that can be done prior to developing the symptom to prevent haemoptysis. Coughing up blood should never be ignored, and medical attention should be sought out, even if it is only small flecks of mucus/phlegm.⁹ However, if more than a few teaspoons of blood are coughed up, or if it is accompanied by chest pain, fever, dizziness, shortness of breath or blood in urine or stool, this is an emergency, and medical attention should be sought out immediately.⁹

Summary 

Coughing up blood can be a symptom of COVID-19 and has been reported both in case studies and medical research. However, it does not occur in the majority of cases and could also be a sign of another serious health condition. A healthcare professional should therefore be sought out whenever someone notices they have coughed up blood, as a medical intervention may be necessary.