Pleurisy: Symptoms, Causes & Treatment

What Is Pleurisy and How Does It Develop?

Pleurisy is inflammation of the pleura, the two-layered membrane surrounding each lung. When these membranes become inflamed, they rub against each other during breathing, causing sharp chest pain. The condition can develop suddenly and affects approximately 1 million people annually in the United States alone.

The pleura consists of two thin layers: the visceral pleura (covering the lungs) and the parietal pleura (lining the chest wall). Between these layers is a small amount of lubricating fluid that normally allows the lungs to move smoothly during breathing. When inflammation occurs, the surfaces become rough and irritated, creating friction and pain with every breath.

Understanding the anatomy helps explain why pleurisy pain behaves the way it does. The parietal pleura contains numerous pain receptors, while the visceral pleura has none. This is why the characteristic sharp pain occurs when the inflamed parietal pleura is stretched during inhalation. The pain typically localizes to one side of the chest, corresponding to the affected area.

Pleurisy can occur at any age but is most commonly diagnosed in adults between 20 and 60 years old. The condition may develop as a primary problem or, more commonly, as a secondary complication of another illness such as pneumonia or viral infection. In many cases, particularly in otherwise healthy young adults, viral infections are the underlying cause and the condition resolves on its own.

The inflammatory process in pleurisy triggers several physiological responses. White blood cells migrate to the affected area, releasing chemical mediators that cause swelling and increased blood flow. This inflammation can sometimes lead to fluid accumulation in the pleural space, a complication known as pleural effusion, which may actually reduce pain as the fluid separates the inflamed surfaces.

Dry vs. Wet Pleurisy

Physicians distinguish between two forms of pleurisy based on whether fluid accumulates in the pleural space. Dry pleurisy (fibrinous pleurisy) involves inflammation without significant fluid accumulation. This form typically causes more intense, sharp pain because the inflamed pleural surfaces rub directly against each other. A characteristic "pleural friction rub" can often be heard through a stethoscope.

Wet pleurisy (pleurisy with effusion) occurs when fluid builds up between the pleural layers. While this may paradoxically reduce the sharp rubbing pain, the fluid accumulation can cause other symptoms such as shortness of breath, particularly if the effusion is large. The underlying cause determines whether the fluid is transudative (watery) or exudative (protein-rich), which has important diagnostic and treatment implications.

What Are the Symptoms of Pleurisy?

The primary symptom of pleurisy is a sharp, stabbing chest pain that intensifies when breathing deeply, coughing, sneezing, or moving. The pain typically occurs on one side of the chest and may radiate to the shoulder or back. Additional symptoms may include shallow breathing, dry cough, fever, and shortness of breath.

The pain of pleurisy has distinctive characteristics that help differentiate it from other causes of chest pain. Patients often describe it as "knife-like" or "stabbing," and it worsens dramatically with respiratory movements. Unlike heart-related chest pain, which is typically dull and pressure-like, pleuritic pain is sharp and clearly related to breathing. Many patients unconsciously adopt a pattern of shallow breathing to minimize discomfort.

The location of pain usually corresponds to the site of pleural inflammation. Most commonly, it occurs on one side of the lower chest or middle chest area. However, because the parietal pleura shares nerve pathways with other structures, pain may be referred to nearby areas. Inflammation of the diaphragmatic pleura (the lower portion) may cause shoulder tip pain or upper abdominal discomfort, which can sometimes be mistaken for other conditions.

Beyond the characteristic chest pain, patients with pleurisy may experience several associated symptoms. A dry, non-productive cough is common, typically worsening the chest pain when it occurs. Many patients with viral pleurisy also experience general malaise, fatigue, and low-grade fever. The combination of these symptoms often mimics a respiratory infection, which is frequently the underlying cause.

Pain Characteristics

• Sharp and stabbing: Often described as being "stabbed with a knife"
• Breathing-related: Worsens with deep inspiration, coughing, or sneezing
• Position-dependent: May improve when leaning forward or lying on the affected side
• Localized: Usually affects one side of the chest
• Radiating: May spread to shoulder, back, or abdomen

Additional Symptoms

While chest pain is the defining symptom, pleurisy often presents with additional features that provide clues about the underlying cause:

• Shortness of breath: Due to pain limiting deep breaths, or from pleural effusion
• Rapid, shallow breathing: Compensatory pattern to minimize pain
• Dry cough: Irritation of the pleura triggers cough reflex
• Fever and chills: Suggest infectious cause
• Fatigue and weakness: Common with viral infections
• Unexplained weight loss: May indicate serious underlying condition

What Causes Pleurisy?

Pleurisy is most commonly caused by viral respiratory infections, but can also result from bacterial pneumonia, pulmonary embolism (blood clot), autoimmune diseases like lupus, chest trauma, or rarely, cancer. Identifying the underlying cause is essential for proper treatment.

Understanding what triggers pleurisy is crucial because treatment depends on addressing the root cause. In many cases, particularly in otherwise healthy adults, viral infections are responsible. These include influenza (flu), respiratory syncytial virus (RSV), adenoviruses, and even the viruses that cause the common cold. Viral pleurisy typically resolves on its own within one to two weeks as the body clears the infection.

Bacterial infections, particularly pneumonia, represent another significant cause of pleurisy. When pneumonia develops near the lung surface, the infection can spread to involve the adjacent pleura. This form of pleurisy, called parapneumonic pleurisy, often leads to pleural effusion and may require antibiotics and sometimes drainage procedures if the fluid becomes infected (empyema).

Autoimmune conditions are an important but often overlooked cause of pleurisy. Systemic lupus erythematosus (lupus), rheumatoid arthritis, and other connective tissue disorders can cause recurring episodes of pleural inflammation. In these cases, the body's immune system mistakenly attacks the pleural membranes. Treatment focuses on controlling the underlying autoimmune disease, often with corticosteroids or immunosuppressive medications.

Common Causes of Pleurisy

• Viral infections: Influenza, common cold viruses, COVID-19, Epstein-Barr virus
• Bacterial pneumonia: Streptococcus, Staphylococcus, and other bacteria
• Pulmonary embolism: Blood clot traveling to the lungs (medical emergency)
• Autoimmune diseases: Lupus, rheumatoid arthritis, sarcoidosis
• Chest trauma: Rib fractures, chest injuries, surgery
• Tuberculosis: Particularly important in endemic areas
• Cancer: Lung cancer or metastatic cancer involving the pleura
• Medications: Some drugs can cause drug-induced lupus with pleurisy

Risk Factors

Several factors increase the likelihood of developing pleurisy. People with chronic lung conditions, weakened immune systems, or certain medical conditions face higher risk. Understanding these risk factors helps in prevention and early recognition:

• Recent respiratory infection or pneumonia
• Autoimmune conditions (lupus, rheumatoid arthritis)
• Recent chest surgery or trauma
• Blood clotting disorders or prolonged immobility
• History of cancer, particularly lung cancer
• Immunocompromised state (HIV, chemotherapy)
• Asbestos exposure

How Is Pleurisy Diagnosed?

Pleurisy is diagnosed through physical examination (listening for a pleural friction rub), chest X-ray to check for fluid or lung abnormalities, and blood tests to identify infection or inflammation. Additional tests like CT scan, ultrasound, or thoracentesis may be needed to determine the underlying cause.

The diagnostic process for pleurisy begins with a thorough medical history and physical examination. Your doctor will ask about the nature of your pain, when it started, what makes it worse, and whether you have associated symptoms like fever, cough, or shortness of breath. Understanding recent illnesses, travel history, occupational exposures, and medical conditions provides crucial context.

During the physical examination, the physician uses a stethoscope to listen to your breathing. A characteristic sound called a "pleural friction rub" is pathognomonic (definitively diagnostic) for pleurisy. This sound resembles creaking leather or rubbing sandpaper and occurs during both inspiration and expiration as the inflamed pleural surfaces move against each other. However, if significant pleural effusion has developed, this sound may be absent because the fluid separates the pleural layers.

Chest X-ray is typically the first imaging study ordered. While it may appear normal in early or mild pleurisy, it can reveal pleural effusion (appearing as fluid collection at the base of the lung), pneumonia, or other lung abnormalities. The X-ray also helps rule out other causes of chest pain such as rib fractures or pneumothorax (collapsed lung).

Diagnostic Tests

• Chest X-ray: Detects pleural effusion, pneumonia, or lung masses
• CT scan: Provides detailed images to identify underlying causes
• Ultrasound: Excellent for detecting and guiding drainage of pleural fluid
• Blood tests: CBC, CRP, ESR to assess inflammation; specific tests for autoimmune diseases
• Thoracentesis: Needle aspiration of pleural fluid for analysis
• D-dimer: Helps rule out pulmonary embolism
• ECG: Rules out heart-related causes of chest pain
• Pleural biopsy: In selected cases to diagnose tuberculosis or cancer

Thoracentesis: What to Expect

If pleural effusion is present, thoracentesis may be performed for both diagnostic and therapeutic purposes. This procedure involves inserting a needle through the chest wall into the pleural space to remove fluid. The fluid is then analyzed for cell count, protein content, glucose, pH, and presence of bacteria or cancer cells. The procedure is performed under local anesthesia and guided by ultrasound for safety and accuracy.

The appearance and laboratory analysis of pleural fluid provides valuable diagnostic information. Clear, straw-colored fluid suggests a transudative effusion (from heart failure or liver disease), while cloudy or bloody fluid may indicate infection, malignancy, or pulmonary embolism. Specific tests on the fluid help distinguish between different causes and guide treatment decisions.

How Is Pleurisy Treated?

Pleurisy treatment focuses on relieving pain with NSAIDs (ibuprofen, naproxen) and addressing the underlying cause. Viral pleurisy usually resolves with rest and anti-inflammatory medication within 1-2 weeks. Bacterial causes require antibiotics, while autoimmune pleurisy may need corticosteroids. Pleural effusion may require drainage.

The treatment approach for pleurisy has two main goals: managing the painful symptoms and treating the underlying condition. Pain relief is typically achieved with nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen, naproxen, or indomethacin. These medications reduce inflammation in the pleura while also providing analgesic effects. Most patients experience significant improvement in pain within the first few days of treatment.

For patients who cannot tolerate NSAIDs or have contraindications (such as kidney disease, stomach ulcers, or certain heart conditions), acetaminophen (paracetamol) can provide pain relief, though it lacks the anti-inflammatory effects. In severe cases, short-term corticosteroids may be prescribed to reduce inflammation, though this is more common in autoimmune-related pleurisy.

Treating the underlying cause is essential for complete resolution. Viral pleurisy typically requires only supportive care, as the infection resolves on its own. Rest, adequate hydration, and fever management with antipyretics support the body's natural healing process. Most patients with viral pleurisy recover fully within one to two weeks.

Treatment by Cause

• Viral pleurisy: Rest, NSAIDs for pain, symptom management, typically resolves in 1-2 weeks
• Bacterial pneumonia: Antibiotics (often 7-14 days), drainage if empyema develops
• Pulmonary embolism: Anticoagulation therapy (blood thinners), sometimes thrombolysis
• Autoimmune causes: Corticosteroids, immunosuppressive medications, disease-specific therapy
• Tuberculous pleurisy: Anti-tuberculosis medication regimen (typically 6-9 months)
• Malignant pleurisy: Treatment of underlying cancer, pleurodesis for recurrent effusions

Self-Care and Home Management

While awaiting medical evaluation or during recovery, several measures can help manage pleurisy symptoms at home:

• Take anti-inflammatory medication: Over-the-counter NSAIDs (ibuprofen 400mg, naproxen 220mg) with food
• Rest adequately: Avoid strenuous activity that increases breathing rate
• Lie on the painful side: This limits movement of the inflamed pleura and reduces pain
• Use pillow support: Splinting the affected side with a pillow when coughing can help
• Practice shallow breathing: Temporarily reduces pain while medication takes effect
• Apply warmth: Some patients find warm compresses soothing
• Stay hydrated: Particularly important if fever is present

When Should You Seek Medical Care?

Seek immediate medical care if you experience severe chest pain, difficulty breathing, high fever, coughing up blood, or rapid heart rate. Any sudden onset of chest pain with breathlessness could indicate pulmonary embolism, a medical emergency requiring urgent treatment.

While many cases of pleurisy are mild and resolve with home treatment, certain symptoms warrant prompt medical evaluation. The challenge with chest pain is distinguishing between conditions that can safely be treated at home and those requiring urgent intervention. Understanding the warning signs helps ensure appropriate care.

New-onset pleuritic chest pain should generally be evaluated by a healthcare provider to determine the underlying cause and ensure appropriate treatment. Even if symptoms are mild, an initial assessment helps rule out serious conditions like pulmonary embolism, which can initially present with seemingly minor symptoms.

Seek Immediate Emergency Care If:

• Sudden, severe chest pain with shortness of breath
• Severe difficulty breathing or unable to catch breath
• Coughing up blood or bloody sputum
• High fever (above 103F/39.4C) with chest pain
• Rapid heart rate, dizziness, or feeling faint
• Bluish discoloration of lips or fingertips
• Chest pain after recent surgery, trauma, or prolonged immobility

Schedule a Doctor's Appointment If:

• Chest pain persists for more than a few days without improvement
• Pain significantly limits your ability to breathe normally
• You have a fever that persists despite treatment
• You have an underlying condition (autoimmune disease, heart disease)
• Symptoms worsen despite home treatment
• You've had recurrent episodes of similar chest pain

What Complications Can Pleurisy Cause?

Pleurisy can lead to pleural effusion (fluid accumulation between lung layers), empyema (infected fluid collection requiring drainage), pleural adhesions (scarring that may limit lung expansion), and chronic pain. Prompt treatment of the underlying cause minimizes complication risk.

Most cases of pleurisy resolve without complications, particularly when caused by viral infections and treated appropriately. However, understanding potential complications helps emphasize the importance of proper diagnosis and treatment, especially when symptoms persist or worsen.

Pleural effusion is the most common complication, occurring when inflammation causes fluid to accumulate in the pleural space. Small effusions may not cause additional symptoms, but larger ones can compress the lung and cause significant shortness of breath. Treatment depends on the size and cause: small effusions may resolve on their own, while larger ones may require drainage through thoracentesis.

Empyema develops when bacteria infect the pleural fluid, creating a collection of pus in the pleural space. This serious complication occurs most often with bacterial pneumonia and requires aggressive treatment including antibiotics and drainage procedures. If not adequately treated, empyema can lead to lung damage and life-threatening sepsis.

Potential Complications

• Pleural effusion: Fluid accumulation causing breathlessness
• Empyema: Infected fluid collection requiring drainage and antibiotics
• Pleural adhesions: Scar tissue formation between pleural layers
• Trapped lung: Permanent lung restriction from thick pleural scarring
• Chronic pain: Persistent discomfort in some cases
• Respiratory compromise: From large effusions or lung restriction

Can Pleurisy Be Prevented?

Pleurisy can often be prevented by addressing risk factors: get vaccinated against flu and pneumonia, treat respiratory infections promptly, manage underlying conditions like lupus, avoid smoking, and take precautions against blood clots during prolonged immobility.

While not all cases of pleurisy can be prevented, reducing your risk of the underlying conditions that cause it is an effective strategy. Many preventive measures align with general recommendations for respiratory and overall health.

Vaccination plays an important role in preventing infectious causes of pleurisy. Annual influenza vaccination reduces the risk of flu and its complications, including viral pleurisy. Pneumococcal vaccines protect against the most common cause of bacterial pneumonia, which frequently leads to pleurisy. Ensure your vaccinations are up to date, especially if you're in a high-risk group.

Managing chronic conditions reduces the risk of pleurisy flares. If you have an autoimmune disease like lupus or rheumatoid arthritis, working with your healthcare team to keep the disease well-controlled helps prevent pleural inflammation. Regular follow-up appointments and taking medications as prescribed are essential.

Prevention Strategies

• Stay up to date on vaccinations: Flu shot annually, pneumonia vaccines as recommended
• Practice good respiratory hygiene: Wash hands frequently, avoid sick contacts
• Treat infections promptly: Don't ignore respiratory infections
• Don't smoke: Smoking damages lungs and increases infection risk
• Control autoimmune diseases: Follow treatment plans, attend regular checkups
• Prevent blood clots: Move regularly during long trips, follow post-surgery guidelines
• Maintain overall health: Regular exercise, balanced diet, adequate sleep

What Is the Outlook for Pleurisy?

The prognosis for pleurisy is generally excellent when caused by viral infections, with most cases resolving completely within 1-2 weeks. Outcomes depend on the underlying cause: infectious pleurisy typically resolves with appropriate treatment, while autoimmune or malignant causes may require ongoing management.

The long-term outlook for pleurisy varies significantly based on the underlying cause. For the majority of patients with viral pleurisy, the prognosis is excellent. The inflammation resolves as the body clears the infection, and most people return to full normal activity within one to two weeks without any lasting effects.

Bacterial causes of pleurisy also generally have good outcomes when treated promptly with appropriate antibiotics. However, if complications like empyema develop, recovery may be prolonged and require additional interventions. Early recognition and treatment are key to preventing such complications.

Pleurisy related to autoimmune conditions may recur as part of disease flares. Long-term management focuses on controlling the underlying autoimmune disease to prevent both pleural involvement and other organ complications. With appropriate treatment, most patients achieve good symptom control.

In cases where pleurisy is caused by serious underlying conditions like malignancy or pulmonary embolism, the prognosis is primarily determined by these underlying diseases rather than the pleurisy itself. This underscores the importance of thorough evaluation to identify the root cause.