Overview: What is pleural empyema?
In pleural empyema, pus accumulates in the pleura, more precisely between the two pleural sheets of the pleura. These pleural sheets are called the visceral pleura and the parietal pleura. The word “empyema” comes from the Greek “empyein” and means “to fester”. Another technical term for pleural empyema is pyothorax.
This accumulation of pus occurs when bacteria enter the gap between the pleural sheets. This usually occurs as a result of bacterialpneumonia, which spreads to the pleura (pleurisy). People with pleural empyema often suffer from a severe feeling of illness. Symptoms include high fever, shortness of breath, chest pain or night sweats.
Pleural empyema progresses in different stages. Initially, the inflammatory fluid in the pleural cavity is watery. Later it mixes with pus. The treatment depends on how severe the pleural empyema is and what stage it is at.
Pleural empyema must be recognized as quickly as possible and treated consistently in order to prevent the prognosis from worsening. Antibiotics are used, as well as drainage, which is used to remove the secretions from the pleural empyema. In severe cases, an operation can help, in which surgeons remove the accumulation of pus.
Pleural empyema – frequency and age
Pleural empyema is a relatively common inflammatory disease of the chest cavity. In 20 to 60 percent of patients with pneumonia, a parapneumonic effusion develops, which can develop into pleural empyema. In principle, the disease can occur at any age. It can affect younger, previously healthy people as well as older people with existing underlying conditions. Men are affected about twice as often as women.
Pleural empyema: causes and risk factors
The cause of the formation of pus is always an inflammation, which in most cases is caused by bacteria. The bacteria and the white blood cells that attract the invading pathogens release special proteins (enzymes). These ensure that the neighboring cells digest themselves. Pus develops. In pleural empyema, this accumulation of pus forms between the two pleural sheets, i.e. between the pleura and the pleura. There are several possible causes of pleural empyema.
Pleural empyema: often caused by pneumonia
The most common cause of pleural empyema is bacterial pneumonia. The bacteria spread to the pleura and cause inflammation there (pleuritis). From there, they enter the gap between the pleura and pleura and a so-called “parapneumonic effusion” forms. It is divided into three forms according to its course: uncomplicated and complicated parapneumonic effusion through to fully developed pleural empyema. The transitions are usually fluid. Various types of bacteria are often involved in pleural empyema, but above all staphylococci and pneumococci.
Pleural empyema – other causes
There are also other known causes of pleural empyema, for example:
- Injuries in the chest cavity (e.g. accidents). This can be a haematoma in the chest cavity (haematothorax), for example.
- Injuries due to surgery. Interventions in the chest cavity (thoracic drainage, puncture of an effusion), the heart, the urinary tract or the abdominal cavity. If pleural empyema is acquired in hospital, doctors refer to it as “nosocomial”.
- Lung diseases. This includes lung cancer (bronchial carcinoma).
- Inflammation outside the lungs. For example, if the pathogens are spread from another focus of inflammation in the body: e.g. pancreatitis and peritonitis, liver abscess, inflammation below the diaphragm – the pathogens enter the pleural cavity via the blood and lymph channels.
- Blood poisoning (sepsis).
- Inhalation of foreign bodies (foreign body aspiration). For healthy people or people with swallowing disorders.
Risk factors for pleural empyema
Several risk factors are known that can promote pleural empyema. Most are associated with a suppressed immune system (immunosuppression). Examples are:
- HIV infection, organ transplantation
- Chronic renal insufficiency (chronic kidney failure)
- Diabetes mellitus
- Chronic obstructive pulmonary disease(COPD)
- Malnutrition
- Alcohol and drug abuse
- Neurological diseases that are associated with swallowing disorders and increase the risk of inhaling foreign bodies, such as a stroke or dementia.
Parapneumonic effusion to pleural empyema – the phases
Doctors differentiate between complicated and uncomplicated effusion and fully developed pleural empyema. These processes take place in the various phases:
- Uncomplicated parapneumonic effusion: Due to pneumonia, the fluid between the cells in the lungs increases and overflows into the pleural cavity. If the pneumonia heals, the effusion also recedes.
- Complicated parapneumonic effusion: In addition, neutrophil granulocytes (a special type of white blood cell) migrate into the pleural cavity. The body activates the formation of fibrin, a protein that plays an important role in blood clotting. This creates small, uninfected chambers.
- Pleural empyema: Secretions and pus accumulate in the pleural cavity. There are different stages of pleural empyema.
Symptoms: Pleural empyema causes high fever
Those affected often blame pleural empyema on bacterial pneumonia. Most people have no idea that disaster is brewing in the pleura.
The following symptoms can occur with pleural empyema:
- High fever
- Shortness of breath
- Chest pain
- Shoulder pain
- Tiredness, fatigue, exhaustion
- Cough, purulent sputum
Always seek medical advice if you notice such signs of infection. Without treatment, pleural empyema can significantly impair lung function and therefore quality of life.
Pleural empyema: Diagnosis by us
We always begin the diagnosis of pleural empyema with a discussion of your medical history (anamnesis). We will ask you some questions, for example:
- What symptoms do you have?
- When did the symptoms first occur?
- How severe are the symptoms?
- Do you have any known illnesses, for example pneumonia?
- Are there other diseases outside the lungs?
- Are you taking medication? If yes, which ones and since when?
- Have you recently undergone an operation? If so, which one and when?
- Have you recently had an accident or injury?
This is followed by a physical examination, during which we listen to and palpate the lungs. This allows unusual noises to be detected. However, such altered sounds can also occur in the context of many other lung diseases.
Further examinations are carried out to establish the diagnosis of pleural empyema:
- X-ray examination. The X-ray image shows fluid accumulations that compress the lungs.
- (sonography) of the chest
- Computed tomography (CT). This X-ray examination provides even more precise cross-sectional images of the lungs. The CT images show where the pleural empyema is located and how large it is.
- Blood test. The blood values provide indications of inflammation in the body, e.g. the C-reactive protein (CRP). However, this inflammation marker is not specific for pleural empyema, but only shows that inflammation is present somewhere in the body. The number of leukocytes (white blood cells) is also increased.
- Pleural puncture. We take a secretion sample from the pleural cavity with a fine needle. Laboratory doctors then analyze the fluid for various pathogens. They also analyze other parameters such as the pH value, the enzyme lactate dehydrogenase, glucose and neutrophil granulocytes (a specific type of white blood cell). These values are altered in pleural empyema. This allows us to determine the stage.
Pleural empyema – three stages
Pleural empyema can be divided into three stages according to its development – from uncomplicated pleural effusion to fully developed pleural empyema:
- Stage 1 (exudative phase): Due to inflammatory processes in pneumonia, the vessels of the pleura become more permeable and a clear secretion (without bacteria) forms.
- Stage 2 (fibrinous-purulent phase): Bacteria migrate into the pleural cavity up to 14 days later. The body produces more fibrin and chambers form. Neutrophil granulocytes appear on the scene, bacteria metabolize glucose to carbon dioxide and lactate – the pH value and the glucose value drop. In addition, the value of the enzyme lactate dehydrogenase (LDH) increases. The secretion is purulent and cloudy.
- Stage 3 (scarring, organizing phase). The fibrin chambers transform into a chamber system with thick walls. The two pleural leaves form rinds that surround the lungs like an armor. This means that the lung can no longer expand properly and is “trapped”. Those affected have breathing problems. The secretion is purulent or viscous.
Pleural empyema: prevention, early detection, prognosis
No special measures for the prevention and early detection of pleural empyema are known. However, pleural empyema often develops on the breeding ground of bacterial pneumonia. Always have them adequately treated with medication (antibiotics). Cure the pneumonia completely so that all bacteria are eliminated. In this way, you may be able to prevent the development of pleural empyema.
It is important that we recognize pleural empyema as early as possible and treat it consistently. Otherwise the lung function sometimes suffers for the rest of your life. In general, therefore, if you notice symptoms such as fever, shortness of breath or fatigue, you should always consult your doctor promptly and have your symptoms checked out.
Course and prognosis of pleural empyema
We must recognize pleural empyema as quickly as possible and treat it adequately, otherwise the course and prognosis will worsen. This is particularly true for older people, who often also have serious underlying illnesses. In the long term, pleural empyema can lead to remodeling of the pleura and scarring. These consequences are called pleural callosities or pleural rinds. Lung disease can severely impair respiratory function and everyday life.
The majority of pleural empyema cases require antibiotic therapy and surgery to remove the pus and clean the pleural cavity. Only the very early forms can be treated with antibiotics alone.
Pleural empyema: treatment depending on the stage
The treatment of pleural empyema depends on the stage of the disease.