How Are Pleurisy and Other Disorders of the Pleura Diagnosed?

Your doctor will find out if you have pleurisy or another pleural disorder by taking a detailed medical history and doing a physical exam and several tests. The purpose is to:

• Rule out other causes of your symptoms
• Find the cause of the pleurisy or other pleural disorder so it can be treated

Medical History

Your doctor will ask you for a detailed medical history. He or she is likely to ask you to describe the pain, especially:

• What it feels like
• Where it's located and whether you can feel it in your arms, jaw, or shoulder
• When it started and how long you've had it
• What makes it better or worse
• Whether it goes away and then comes back

Your doctor will probably also want to know about any other symptoms that you may have, like shortness of breath, cough, or palpitations (a feeling that your heart has skipped a beat or is beating too hard).

Other things your doctor is likely to ask about include whether you've ever:

• Had heart disease
• Smoked
• Traveled to places where you may have been exposed to tuberculosis
• Had a job that exposed you to asbestos
• Taken nitrofurantoin or amiodarone or a medicine that can cause a condition that's similar to systemic lupus erythematosus (an autoimmune disorder)

Physical Exam

Your doctor will listen to your breathing with a stethoscope to find out whether your lungs are making any strange sounds.

When you have pleurisy, the inflamed layers of the pleura make a rough, scratchy sound as they rub against each other when you breathe. Doctors call this a pleural friction rub. If your doctor hears the friction rub, he or she will know that you have pleurisy.

If you have a pleural effusion, fluid has built up in the pleural space and pushed the two layers of the pleura apart so that they don't produce a friction rub. But if you have a lot of fluid, your doctor may hear a dull sound when he or she taps on your chest. Or the doctor may have trouble hearing any breathing sounds.

Reduced breathing sounds also can be a sign of pneumothorax.

Diagnostic Tests

Depending on the results of your physical exam, your doctor may recommend other diagnostic tests.

Chest X Ray

A chest x ray takes a picture of your heart and lungs. It may show air or fluid in the pleural space. It also may show what's causing the condition—for example, pneumonia, a fractured rib, or a lung tumor.

Sometimes an x ray is taken while you lie on the side where the pain is. This may show fluid that didn't appear on the standard x ray taken while you were standing.

Computerized Tomography (CT) Scan

This test provides a computer-generated picture of your lungs that can show pockets of fluid. It also may show signs of pneumonia, a lung abscess, or a tumor.

Ultrasound

This test uses sound waves to create pictures of your lungs. It may show where fluid is located in your chest. It also can show some tumors.

Magnetic Resonance (MR) Scan

This test also is called nuclear magnetic resonance (NMR) scanning or magnetic resonance imaging (MRI). It uses powerful magnets and radio waves to show pleural effusions and tumors.

Blood Tests

Blood tests can show whether you have a bacterial or viral infection, pneumonia, rheumatic fever, a pulmonary embolism, or lupus.

Arterial Blood Gas Tests

In this test, a small amount of blood is taken from an artery in your wrist. It's then checked for oxygen and carbon dioxide levels. This test shows how well your lungs are taking in oxygen.

Thoracentesis

Once your doctor knows whether fluid has built up in the pleural space and where it is, he or she can remove a sample for testing. This test is called thoracentesis (THOR-a-sen-TE-sis). The doctor inserts a small needle or a thin, hollow, plastic tube through the ribs in the back of your chest into your chest wall and draws fluid out of your chest.

Thoracentesis usually doesn't take long. Most of the time, it can be done in your doctor's office or at your hospital bed. Many doctors use ultrasound to guide the needle to the fluid that's trapped in small pockets around your lungs.

Thoracentesis usually doesn't cause serious complications, but your doctor may do a chest x ray after the procedure to be sure. Most of the complications are minor and will get better on their own, or they're easily treated.

Possible complications of thoracentesis include:

• Pneumothorax, or buildup of air in the pleural space, with a collapsed or partially collapsed lung. Sometimes air comes in through the needle or the needle makes a hole in your lung. Usually, a hole will seal itself. But sometimes air can build up around the lung and make it collapse. The doctor may need to use a chest tube to remove the air and let the lung expand again.
• Pain.
• Bleeding and bruising where the needle went in. In rare cases, bleeding may occur in or around the lung. The doctor may need to use a chest tube to drain the blood. In some cases, surgery may be needed.
• Infection where the needle went in.
• Liver or spleen injury. This is very rare.

Fluid Analysis

Doctors look at the fluid removed by thoracentesis under a microscope. They look at the chemicals in it and its color, texture, and clearness for signs of infection, cancer, or other conditions that may be causing the buildup of fluid or blood in the pleural space.

Biopsy

If your doctor thinks that tuberculosis or cancer may have caused the fluid buildup, he or she may want to look at a small piece of the pleura under a microscope.

To take a tissue sample, the doctor may:

• Insert a needle through the skin on your chest to remove a small sample of the outer layer of the pleura.
• Insert a small tube with a light on the end (endoscope) into tiny cuts in your chest wall so that the doctor can see the pleura. He or she can then snip out small pieces of tissue. This procedure must be done in the hospital under general anesthesia.
• Snip out a sample of the pleura through a small cut in your chest wall. This is called an open pleural biopsy. It's usually done if the sample from the needle biopsy is too small for an accurate diagnosis. This procedure must be done in the hospital under general anesthesia.