Pleurisy

What is Pleurisy?

Pleurisy is a condition characterized by chest pain due to inflammation of the pleura, the thin layers of tissue surrounding your lungs. This pain can arise from either a disease that primarily affects the pleura, or it can be a symptom of a wider, systemic illness. This condition has been known since ancient times. Originally, it was known as ‘pleuritis’ and was described as causing fever, chills, and difficulty breathing. Over the years, as our understanding of the condition grew, other symptoms were recognized such as changes to one’s pulse rate.

The term ‘pleurisy’ came into use in the 18th century, when a physician described it as having symptoms like fever, difficulty in producing spit, and pain in the side of your chest. In the 1960s, another doctor studied patients who had died of pleurisy and realized that it is closely related to diseases of the lung as well. And finally, the doctor who invented the stethoscope, introduced new terms to better describe this condition: ‘pleuritic’ to refer to the inflammation of the pleura, and ‘pleurisy’ for the disease that causes this inflammation.

When we speak of pleura, we are referring to two layers of thin tissue that separate your lungs from your chest wall. The layer surrounding your lung is known as the visceral pleura while the one lining your chest wall is known as the parietal pleura. They’re quite different in structure and function. For example, the parietal pleura contains small openings that allow fluid to drain through to nearby tissue, where it’s carried away by the body’s lymphatic system, a network of vessels and organs that work to keep the body clean of toxins and waste.

The space between these two tissue layers normally contain a small amount of fluid. This lubricates the tissues and allows the lungs to expand and contract smoothly when you breathe. But when more fluid than necessary builds up, or if it’s not properly draining, it can lead to inflammation and thus pleurisy.

The pleura are designed so the lung can move freely within the chest during breathing. Every time you take a breath in, your chest and diaphragm create a vacuum that expands your lungs. This vacuum pulls air from outside into your lungs, aiding in the process of respiration.

What Causes Pleurisy?

Inflammation of the pleura, the thin tissue that covers the lungs and lines the chest cavity, can happen due to various conditions. This inflammation can occur very suddenly – within minutes to hours. Some causes could be a punctured lung (pneumothorax), heart diseases (acute coronary syndromes), blood clots in the lungs (pulmonary emboli), inflammation of the heart’s lining (acute pericarditis), and trauma to the chest wall. People with these conditions may experience rapid breathing and shortness of breath.

The pleura can also become inflamed due to viral or bacterial lung infections. When this happens, the inflammation develops over a few hours to days. Moreover, 20 to 40% of hospitalized patients with pneumonia develop fluid build-up in the pleural space, known as a parapneumonic effusion. Draining the fluid build-up through thoracentesis is recommended for any new accumulation, especially if pneumonia is suspected.

Conditions like Familial Mediterranean fever, thoracic endometriosis, and recurrent collapses of the lung can cause the pleura to become inflamed over and over again.

Some conditions, like rheumatoid arthritis, cancer, or tuberculosis, can result in long-lasting, or chronic inflammation of the pleura. Tumors, either spreading from other parts of the body or originating in the pleura itself, such as pleural lymphomas, angiosarcoma of the pleura, and pleuropulmonary blastoma, can also lead to pleuritic pain. Mesothelioma, a particular type of lung cancer caused by asbestos exposure, is a rare cause of pleurisy, and typically occurs in men over 60 years old who have a history of occupational asbestos exposure. This can cause severe and chronic pain in the pleura.

Risk Factors and Frequency for Pleurisy

The causes of a medical condition called pleuritis, or pleurisy, can be influenced by several factors. These factors can include:

• The place where a person lives (geographic factor)
• The person’s age, gender and ethnicity (demographic factors)
• The person’s job (occupational factor)
• Other health conditions the person might have (comorbid factors)
• Various other factors that can influence a person’s health.

Signs and Symptoms of Pleurisy

Pleuritis is a condition where you feel sharp pain in your chest or shoulder. This pain can increase when you move, cough, sneeze, or take deep breaths. It can also feel like a dull ache, burning or like something’s caught in your chest. How long this pain lasts or how often it happens can often give clues about what’s causing it. Diagnosing pleuritis usually involves discussing your symptoms and medical history with a healthcare provider.

Key factors that can help diagnosis include how suddenly the pain came on, how long it lasts and how the symptoms change over time. These can point to conditions such as pulmonary embolism, spontaneous pneumothorax or inflammation from chest trauma. Providers will also look for any long-term illnesses you may have like lupus, HIV, or tuberculosis, which can contribute to pleuritis.

Personal habits and lifestyle also play a role in helping identify possible causes. Information about your travels, smoking habits, drinking habits, and drug use can sometimes point towards the cause of these symptoms. A physical examination may reveal other signs like a “pleural rub” sound in your chest during deep breaths, differences in the sounds when they tap on your chest, or changes in your breathing sounds.

• Sharp pain in chest or shoulder – worsens with movement or breathing
• Pain can also feel like a dull ache, burning or ‘catching’
• Chronic illnesses such as lupus, HIV, or tuberculosis can contribute to pleuritis
• Personal habits like travel, smoking, drinking and drug use can be relevant
• Physical exams might reveal ‘pleural rub’ sounds, chest sounds, or changes in respiratory rhythm

Testing for Pleurisy

If you’re experiencing chest pain, mostly on the left side, your doctor may need to check if it’s because of a heart condition. Therefore, you may be asked about your medical history and have tests such as an electrocardiogram, which checks your heart’s electrical activity, and a serum troponin test, which checks for a protein in the blood that can indicate heart damage.

Even though chest pain that worsens when you take a breath or cough is usually not related to heart disease, in some cases, heart-related issues like inflammation of the heart’s outer layer (acute pericarditis) or a tear in the aorta (aortic dissection) are the culprits. Both conditions can cause severe chest pain or discomfort that can also be felt in the shoulder region.

Your doctor may order a chest x-ray to check for lung conditions such as infection, accumulation of fluid in the chest (pleural effusion), or collapsed lung (pneumothorax). They may also do blood tests to get a complete count of your blood cells and to check the levels of a few specific substances in your blood, such as protein, albumin, and lactate dehydrogenase. The latter test can suggest tissue injury in the body.

If your doctor suspects that complications of inflammation of the pancreas (acute pancreatitis) are causing chest pain and fluid collection, they may decide to test your blood for an enzyme called lipase. High levels of this enzyme can indicate pancreatitis.

In case fluid is found in the space around your lungs (pleural effusion) or heart (pericardial effusion), your doctor might need to take a sample and check it for acidity (pH level), glucose level, types and numbers of cells, lactate dehydrogenase level, and signs of bacterial infection. The latter would be indicated by a special type of light and color stain (gram stain) and the growth of bacteria from the fluid sample.

Still, a chest x-ray may not show small tumors or minimal fluid build-up in the chest. Hence, for a thorough assessment, your doctor might recommend a type of x-ray test called computed tomography (CT) scan which can give a more detailed image of your chest. They particularly opt for this test when they suspect collapsed lung, blood clot in the lung (acute pulmonary embolism – which would require the use of intravenous dye), or lung nodules or masses. Suspicion of involvement of the lining of the chest cavity (pleura) could lead the doctor to check the fluid for cancer cells.

Treatment Options for Pleurisy

The treatment for different heart and chest conditions will depend on the specific diagnosis. If someone has acute coronary syndromes, a heart condition that includes symptoms like chest pain and breathlessness, they should be treated by a heart specialist. For a dangerous condition called aortic dissection, which involves a tear in the large blood vessel branching off the heart, emergency surgery would typically be necessary.

Another condition is a collapsed lung or pneumothorax, which can be caused by injury or lung disease. In severe cases, the trapped air in the chest cavity needs to be released. This would usually involve a procedure called needle aspiration, which uses a needle to suck the air out, or a chest tube to allow the air to drain out. The decision between these options would depend on whether the patient is stable and the cause of the pneumothorax.

In the case of a pulmonary embolism, where a blood clot gets lodged in an artery in the lungs, treatments range from home treatment with blood thinners (anticoagulants), to hospital treatment with similar medications or other techniques to break up the clot. How severe the condition is, the patient’s overall health, where they live, and other factors would all affect the treatment decision.

Pleural effusion, in which excess fluid builds up in the chest, involves different treatments based on the size and other characteristics of the fluid build-up. Smaller effusions (less than 10 mm) usually don’t require treatment. Larger effusions often require a procedure called thoracentesis to remove the fluid and test it for infection. Very large effusions or those associated with infection (empyema) might need a chest tube to drain the fluid, or even surgery. The choice between these treatments would depend on the specific characteristics of the effusion.

A trial found that a combination treatment using tissue plasminogen activator (a drug that helps dissolve clots) and deoxyribonucleic acidase (an enzyme that breaks down DNA) showed significant improvements in patients with larger effusions or empyema. This combination of drugs reduced the hospital stay length, the size of the effusion, and the need for surgery, compared to placebo treatment.

What else can Pleurisy be?

When a patient experiences chest pain, doctors will typically assess them for certain serious health conditions. These include:

• Acute coronary syndromes (conditions like heart attack caused by sudden, reduced blood flow to the heart)
• Aortic dissection (a serious condition involving a tear in the aorta)
• Pneumothorax (collapsed lung)
• Pericardial effusion/tamponade (fluid or blood around the heart affecting its function)
• Pulmonary embolism (a blockage in the lung arteries)

Once they have ruled out these conditions using imaging scans and blood tests, doctors may also consider:

• Pleural effusions (fluid build-up between the layers of tissue lining the lungs and chest cavity)
• Pericarditis (inflammation of the pericardium, the protective sac around the heart)
• Pulmonary infectious processes (lung infections)
• Intrathoracic malignancies (cancer within the chest cavity)

What to expect with Pleurisy

The outlook for pleurisy (inflammation of the membrane that surrounds and protects the lungs) and pleuritic chest pain can vary based on the cause and how effectively it is treated. Conditions such as acute coronary syndromes (a group of conditions that include heart attacks and unstable angina), aortic dissection (a severe condition in which the inner layer of the aorta splits open), pneumothorax (a collapsed lung), and pulmonary embolism (a blockage in one of the pulmonary arteries in your lungs) can be quite serious and even fatal if they are left untreated.

Category 3 and 4 pleural effusion, also known as complicated parapneumonic effusion or empyema (build-up of fluid in the pleural space due to pneumonia or lung abscess), has a high mortality rate of around 30% and can also cause long-term health problems if not treated effectively.

Lupus pleuritis, a condition where the lungs become inflamed due to lupus, doesn’t significantly impact life expectancy, but it can affect quality of life. This condition occurs in 43% of patients with systemic lupus erythematosus (a chronic disease that causes inflammation in various parts of the body) at some point during their illness.

Malignant pleural disease, a serious condition where the lung’s protective covering is affected by cancer, has a very poor outlook, with a median survival rate of 13 months after diagnosis in one series of cases.

Possible Complications When Diagnosed with Pleurisy

Empyemas and parapneumonic effusions—fluid around the lungs caused by pneumonia—can result in thickening of the lung lining. If not properly treated, this can cause the lung to become trapped, repeated cases of pneumonia, or infections in the bloodstream. A buildup of fluid due to cancer can also make the lung lining thick and fibrous, leading to a condition called restrictive lung disease.

Blood clots in the lungs, known as pulmonary emboli, can lead to high blood pressure in the lungs. This can result in chronic shortness of breath, difficulty with physical activity, or low oxygen levels in the blood. If not treated quickly, these blood clots can also result in death or a long stay in the hospital.

Key Points:

• Empyemas and parapneumonic effusion lead to the thickening of the lung lining
• The thickening of the lung lining may cause trapped lung, repeated pneumonia and bloodstream infections
• Fluid buildup due to cancer can lead to thick, fibrous lung lining and restrictive lung disease
• Blood clots in the lungs can cause pulmonary hypertension
• Pulmonary hypertension can result in chronic shortness of breath, physical activity difficulty or low oxygen levels
• Blood clots can potentially cause death or a longer hospital stay if not treated promptly