What Is Empyema?

Empyema, also referred to as pyothorax or purulent pleuritis, is a condition in which pus forms between the lungs and the inner surface of the chest wall. The pleural space refers to this region. Pus is a clear fluid containing immune cells, dead cells, and bacteria. Coughing cannot remove pus from the pleural space. It must instead be drained through a needle or surgery. Empyema commonly develops as a result of pneumonia, which is a lung infection.

Empyema Vs Pleural Effusion

Pleural effusion, also known as “water on the lungs,” is the accumulation of excess fluid between the layers of the pleura, outside the lungs. The pleura are thin membranes that line the lungs and the inside of the chest cavity, lubricating and making breathing easier.
Empyema, on the other hand, is characterized by the accumulation of purulent fluid in the pleural space, which is most commonly caused by pneumonia.

An empyema can look like a pleural effusion or a peripheral pulmonary abscess. The following characteristics distinguish a pleural effusion from an empyema:

Shape and Location

Empyema usually:

• Form an obtuse angle with the chest wall
• Are frequently unilateral or markedly asymmetric, whereas pleural effusions are usually
• Are bilateral and equal in size (if of any significance)
• Are lenticular in shape (biconvex) whereas pleural effusions crescentic in shape

Findings on CT

The following characteristics are suggestive of an empyema:

• Evident septations
• Related consolidation
• Pleural effusion has thin imperceptible pleural surfaces, whereas empyema has thickened pleura
• Unless a recent thoracocentesis, gas locules are absent.
• Adjacent infection associated (e.g. subdiaphragmatic abscess)

What Causes Empyema?

The most common cause of empyema is pneumonia, which frequently begins with parapneumonic pleural effusion, but the physiology varies. The number of patients suffering from empyema is rising in both children and adults. Empyema has a mortality rate of 10–20 percent, long hospital stays, and a high financial burden. One-third of those being treated require surgical intervention. Pneumonia can be caused by a variety of bacteria, but the two most prevalent are Streptococcus pneumoniae and Staphylococcus aureus. It’s also possible that you’ll get empyema after having chest surgery. Bacteria can be transferred into your pleural cavity through medical devices.

The pleural space contains some fluid by nature, but infection can cause fluid to accumulate faster than it can be absorbed. The bacteria that cause pneumonia or infection then infect the fluid. The contaminated fluid thickens which has the potential to cause the lining of your lungs and chest cavity to stick together and form pockets.

Types of Empyema

Empyema can either be simple or complex. Also, the presence of an infection, as well as pressure on the lungs and chest produced by an increase in fluid in the pleural space, can induce symptoms of an empyema.

Simple Empyema

These are exudative, primarily neutrophilic effusions that show increased interstitial fluid flow as a result of pneumonia-related inflammation. The fluid could be somewhat hazy or transparent, with no visible organisms on Gram stain or culture. They will go away if the pneumonia is treated with antibiotics. Simple empyema symptoms include:

• breathing difficulty
• coughing fits
• fever
• sweating
• headache
• confusion
• appetite loss
• when breathing, you may experience stabbing chest pain

Complex Empyema

In the later stages of the illness, complex empyema develops. The inflammation is more severe in complex empyema. Scar tissue can grow in the chest cavity, dividing it into smaller compartments. This is known as loculation, and treating it is more challenging. If the infection worsens, it can result in the production of a thick peel across the pleura, known as a pleural peel.

Other signs and symptoms of complicated empyema are:

• breathing problems
• decreased sounds of breathing
• losing weight
• chest discomfort

Risk Factors of Empyema

Having recently experienced pneumonia is the highest risk factor for empyema.
Other aspects to consider are:

• being over the age of 70
• having recently spent time in the hospital
• having had surgery on the chest or been in a car accident

People with the following conditions are statistically more likely to develop empyema:

diabetes
coronary heart disease
cancer in the past
COPD (chronic obstructive pulmonary disease) (COPD)
pulmonary disease
use of intravenous drugs (in simple empyema cases)

Complications of Empyema

Long-term negative effects of pleural infection include residual pleural thickening on chest computed tomography (CT) and, if untreated, fibrothorax and pleural calcification. Once the pleural infection has been adequately controlled, a thickened pleura, also known as a pleural peel usually begins to regress. Complex empyema can, in rare cases, lead to more serious complications. Sepsis and a collapsed lung, known as a pneumothorax, are examples of these. Sepsis causes the following symptoms:

• chills
• high fever
• breathing quickly
• heart rate that is quick
• blood pressure that is low

Other complications include:

Fibrosis

Fibrosis is a condition in which damaged lung tissue causes difficulty breathing, lowering a person’s quality of life. If breathing difficulties persist 6 months after infection, decortication surgery may help.

Empyema Necessitatis

This is an infection that spreads to the chest wall and soft tissue. This is extremely rare and necessitates immediate medical attention.

How to Diagnose Empyema

To confirm a diagnosis, your doctor will likely do the following tests or procedures:

• X-rays and CT scans of the chest will reveal whether there is fluid in the pleural space.
• An ultrasound of the chest will reveal the volume and location of the fluid.
• Blood tests can be used to monitor your white blood cell count, look for C-reactive protein, and identify the bacterium that is infecting you. When you have an illness, your white cell count can rise.

How to Treat Empyema

The goal of treatment is to remove the pus and fluid from the pleura while also treating the illness. Treatment options include:

Antibiotics

Antibiotics are frequently prescribed as the first line of treatment for simple cases of empyema. Finding the proper antibiotic is critical since different bacteria strains induce empyema. Aminopenicillins, penicillins with lactamase inhibitors (e.g. co-amoxiclav orpiperacillin-tazobactam), and cephalosporins have high pleural penetration. Aminoglycosides should be avoided since they have low pleural penetration and may be ineffective in the context of pleural fluidacidosis. Treatment with antibiotics usually takes 2 to 6 weeks.

Drainage

A lack of response to antibiotics, as evidenced by a lack of clinical and radiological improvement, is a strong indication for chest tube drainage. The optimal size of the chest tube and duration of drainage are still being debated. However, to prevent simple empyema from escalating to complex or frank empyema, the fluid must be drained. It also aids in the management of the illness. A doctor performs a tube thoracostomy to drain the fluid from the pleural space, which entails introducing an ultrasound or computer-guided tube into the chest cavity and draining the liquid.

Surgery to Remove the Lung Lining

If the problem does not improve, surgery may be required. This entails cutting a hole in the chest to gain access to the lungs and removing the heavy covering that coats them, allowing them to expand correctly once more. This is only done if all other therapies have failed. Your surgeon or expert will go over the procedure’s advantages and disadvantages with you.

Stoma

A chest drain isn’t appropriate for everyone. Some people would rather have a stoma, or a hole in their chest, made. To collect the fluid that escapes from the empyema, a special bag is placed over the stoma.

Now that you Know…

Getting medical help as soon as possible can prevent empyema from worsening. The severity of a person’s symptoms will determine how they are treated for empyema. The first steps are antibiotics and drainage, followed by surgery in more severe instances.