Complications Of Pleurisy: Pleural Effusion, Empyema, And Pleural Thickening

Pleurisy, or pleuritis, is a condition in which the pleura becomes inflamed. The pleura is a thin layer of tissue that covers your lungs and lines your chest cavity. This inflammation causes sharp chest pain that worsens with respiratory movements, coughing, or sneezing. Pleurisy can develop complications, especially if left untreated. Experiencing pleurisy symptoms is uncomfortable, but the complications can be much worse. Early diagnosis and treatment can significantly improve outcomes, prevent possible complications, and avoid further lung damage.¹

Pleurisy: A Quick Recap

Your lungs' outer surface is covered by a thin membrane called the pleura. There are two layers of the pleura: the visceral pleura, which covers the lungs, and the parietal pleura, which is attached to the chest wall.² When these membranes become inflamed, it is called pleurisy. 

Pleurisy can arise from viral or bacterial infections, but it may also stem from other conditions, such as chest wall trauma, acute pericarditis, pulmonary embolism, cancer, connective tissue disorders like rheumatoid arthritis and lupus, or tuberculosis.

If you have pleurisy, you may experience symptoms such as sharp chest pain that worsens with deep breaths, coughing, or sneezing. The pain is often felt in the chest muscles. Other symptoms can include a cough, fever, difficulty breathing, or a general feeling of being unwell. Your doctor may order tests such as blood tests and X-rays to help identify related conditions like pleural effusion or pneumothorax.^2,3

The treatment of pleurisy depends on the underlying cause of the inflammation. For example, if your pleurisy is due to a bacterial infection, your doctor will prescribe antibiotics. If a pulmonary embolism is the cause, anticoagulants and fibrinolytic medications may be administered. If you develop complications such as pleural effusion, your healthcare provider may also perform fluid drainage to treat it. The treatment approach will vary based on the specific cause and your clinical condition.¹

Complications of pleurisy

Pleural Effusion

How it happens

Pleural effusion occurs when fluid builds up in the pleural space, the area between the two thin layers of the pleura. Normally, this space contains a small amount of fluid that helps lubricate the pleura, allowing smooth sliding during breathing. However, when too much fluid accumulates, it can compress the lungs and impair their ability to expand, making breathing difficult and painful. Inflammation of the pleural membranes can trigger an increase in fluid production, leading to excessive fluid accumulation known as pleural effusion.^4,5

Types of pleural effusion

• Exudative Effusion – Caused by inflammation, tumours, cancers, infections, or lung injuries. Different types of fluid can accumulate, such as hemothorax (blood buildup) and empyema (pus buildup)
• Transudative Effusion – Caused by abnormal fluid pressure inside blood vessels due to conditions like congestive heart failure (CHF), kidney disease, malnutrition, or liver disease. The increased pressure pushes excess fluid into the pleural cavity⁵

Symptoms

• Sharp, severe, localised pain, especially when taking a breath, coughing, or sneezing (pleuritic pain)
• Difficulty breathing
• Cough
• Fever
• Fatigue (extreme tiredness)

Treatment for pleural effusion

The primary treatment involves draining the accumulated fluid from the pleural space through a procedure called thoracentesis to reduce symptoms. If there are no symptoms, drainage may be performed to help with diagnosis. A needle or catheter is inserted into the pleural space, and in some cases, a chest tube is placed to drain the excess fluid.

Treatment also focuses on the underlying cause of the pleural effusion. For example, if the cause is an infection, antibiotics will be administered. If pleurisy and pleural effusion are associated with cancer, appropriate cancer management will be provided.^4,6

Empyema

What is empyema? 

Empyema occurs when fluid that has accumulated in the pleural space due to pleural inflammation becomes infected with bacteria, forming pus. This pus can cause areas of the pleura to stick together and create pockets of infection. One of the most common causes of empyema is inadequately treated pneumonia. When pleurisy is caused by bacterial infections such as pneumonia or tuberculosis, empyema can develop as a complication.^7,8

How is it diagnosed? 

Empyema causes symptoms such as:

• Fever and night sweats
• Difficulty breathing
• Pleuritic chest pain.
• Cough-producing mucus or pus
• Weight loss
• Feeling unwell and lacking energy

To diagnose empyema, your doctor will:^7,8

• Perform a physical examination of the chest.
• Analyse mucus from your cough under a microscope
• Order blood tests
• Use a chest X-ray to identify fluid accumulation and its characteristics
• If the X-ray indicates an effusion, an ultrasound can help differentiate between pleural fluid and lung tissue fluid and guide chest tube placement for thoracentesis

A sample of the fluid will be taken for analysis to confirm the diagnosis. In some cases, a CT scan might be needed for a more detailed assessment.

Treatment for empyema

• Antibiotics: Usually given intravenously for 2-6 weeks in the hospital to combat the infection
• Chest drainage: To remove the pus buildup from the pleural space
• Surgical intervention: Typically a last resort if the condition does not improve. The goal is to remove the pus and any thick layers covering the lungs to improve lung expansion This involves making an incision in the chest to access and clean the pleural cavity⁷

Pleural thickening

What is it and how does it happen?

When your pleural layers become inflamed due to pleurisy, they can produce excess fibrin and scar tissue. Over time, this buildup can cause pleural thickening. Other conditions that can cause pleural thickening include exposure to asbestos, lung cancer, chest or rib injuries, infections, and pleural effusions.

If these conditions are not treated effectively, a large amount of fibrin can be deposited in the pleural space, leading to pleural thickening, adhesions (where the pleural layers stick together), and sometimes calcification. Extensive pleural thickening can cause severe ventilation disorders, resulting in breathing restrictions, chest pain, and narrowing of the spaces between the ribs (intercostal spaces).^9,10

How is it diagnosed? 

Symptoms that may present:

• Pleuritic chest pain (sharp pain that worsens with breathing or coughing)
• Cough
• Difficulty taking a deep breath
• Difficulty or inability to take a deep breath⁹

Tests that may help diagnose pleural thickening:

• Chest X-ray: Helps visualise the edges of the lung (pleura), which may appear thickened
• CT Scan: Helps detect thickening of the pleura and other pleural abnormalities
• Ultrasound, MRI, and PET: Additional imaging tests that can provide detailed information about pleural abnormalities¹⁰

Treatment

Pleural thickening cannot be cured, and some patients may not need treatment. However, treatments can be provided to manage symptoms and prevent further damage. Treating the underlying causes is also essential.⁹

FAQs

What is pleural empyema and pleural effusion?

• Pleural Effusion is the accumulation of fluid in the pleural space. The pleural space is the space between two thin layers of pleura, which cover the interior part of the lungs and the chest wall 
• Pleural Empyema: This occurs when the fluid that accumulates in the pleural space becomes infected, forming pus

How long is a hospital stay with empyema?

Studies show that most patients with empyema have relatively long hospital stays, with a median duration of 12-21 days. During this time, they typically receive antibiotic treatment.¹²

Can pleural effusion cause permanent lung damage?

If treated adequately, pleural effusion is less likely to cause permanent lung damage. However, ineffective or inadequate treatment can lead to complications such as pleural thickening, calcification, or further lung damage.

How do they remove empyema from the lungs?

You will be treated with antibiotics to fight the bacteria that caused it. The accumulation of pus in the pleural space may be drained using a needle (thoracocentesis) or chest tube. 

Summary

Pleurisy is an inflammation of the pleura, the thin membranes lining your lungs and chest wall. Various conditions can trigger it, including infections (like pneumonia), cancers, chest injuries, and tuberculosis. If pleurisy is not treated adequately or effectively, several complications can arise. Some common complications of pleurisy include: 

• Pleural Effusion: Inflammation can cause the pleura to produce excess fluid, which builds up in the pleural space (between the lung and chest wall)
• Empyema: This happens when the fluid accumulated in the pleural space becomes infected by bacteria, forming a pocket of pus
• Pleural Thickening: Over time, inflammation can lead to excess scar tissue and fibrin (a clotting protein) buildup, causing the pleura to thicken and stiffen. This can restrict lung function and breathing

These potential complications highlight the importance of seeking medical attention for pleurisy symptoms. Early diagnosis allows for prompt treatment, which can help prevent complications and minimise lung damage.