What is the Difference Between Pleural Effusion and Pleurisy?

Pleurisy, also known as pleuritis, is an inflammation of the pleura, which are the two thin layers of smooth tissue that line the chest cavity and surround the lungs. Pleural effusion, on the other hand, is a buildup of fluid between the two layers of the pleura. Both conditions can cause considerable pain when you inhale and exhale, which can be in the chest, back, or radiate up into the shoulder.

Causes of pleurisy include:

• Viral infection
• Bacterial infection
• Fungal infection
• Certain medications
• Pulmonary embolism (blood clot in the lungs)
• Rib fracture
• Autoimmune diseases, such as rheumatoid arthritis and lupus
• Sickle cell disease
• Lung cancer
• Heart conditions, including a heart attack or pericarditis (inflammation of the membrane surrounding the heart)

Causes of pleural effusion include:

• Congestive heart failure
• Pulmonary embolism
• Pneumonia
• Complications from heart surgery
• Kidney or liver disease
• Blocked blood vessels or lymph vessels
• Lung tumors
• Pulmonary hypertension

Diagnosing pleurisy and pleural effusion begins with a discussion of symptoms and a physical examination. Tests may include:

• X-ray: A chest X-ray can identify the presence of blockages or fluids creating pressure
• Computed tomography (CT) scan: This test combines X-ray and computer technology to produce detailed cross-sectional images of your lungs
• Ultrasound: This type of imaging captures movement to detect the location of the fluid or inflammation and its effects on the lungs
• Thoracentesis: This is a process of removing a sample of fluid from the pleural space to be tested in a laboratory

In some cases of pleurisy, fluid builds up in the small space between the two layers of tissue, called pleural effusion. When there is a fair amount of fluid, pleuritic pain lessens or disappears because the two layers of pleura are no longer in contact. A large amount of fluid in the pleural space can create pressure, compressing the lung to the point that it partially or completely collapses (atelectasis), making breathing difficult and potentially causing coughing. The extra fluid in the pleural space can also become infected, resulting in a buildup of pus (empyema).

Comparative Table: Pleural Effusion vs Pleurisy

Here is a table comparing the differences between pleural effusion and pleurisy:

In summary, pleural effusion is the build-up of excess fluid between the layers of the pleura outside the lungs, while pleurisy is the inflammation of the pleura. Both conditions can cause pain and discomfort, and they can be diagnosed and treated using similar methods.