Empyema
Empyema is a medical condition characterized by the accumulation of pus within a natural body cavity, most commonly occurring in the pleural cavity, which is the space between the chest wall and the lungs. It arises primarily due to bacterial infections that can lead to significant pus buildup, sometimes amounting to one pint or more, which can exert pressure on adjacent organs. In addition to the pleural cavity, empyema can also affect areas such as the pelvis, abdomen, and gallbladder. Symptoms typically include fever, night sweats, sharp pains, and in cases of pleural empyema, difficulty breathing. Diagnosis involves assessing symptoms, physical examinations, and imaging tests like X-rays or CT scans, while pus samples may also be taken for analysis. Treatment focuses on curing the infection and may involve antibiotics, drainage procedures, or surgical interventions depending on the location and severity of the empyema. Preventive measures include timely treatment of infections and proper use of antibiotics. Understanding empyema is vital for recognizing its symptoms and seeking appropriate medical care.
Empyema
- ANATOMY OR SYSTEM AFFECTED: Chest, lungs, skin
- ALSO KNOWN AS: Empyema of the gallbladder, pelvic empyema, purulent or suppurative pleurisy, purulent pericarditis, subdural empyema, thoracic empyema
Definition
Empyema is the collection of pus (a liquid that forms from leukocytes, cellular debris, and protein) in a natural body cavity. Empyema should not be confused with an abscess, which develops its own cavity. Empyema is most common in the pleural cavity, the space between the inside of the chest wall and the lung. Empyema may also occur in other body cavities, such as the pelvis, abdomen, subdural space, gallbladder, and the pericardial sac surrounding the heart.
Causes
Empyema is caused by an infection that leads to the development of pus in a body cavity or space. The amount of pus in such an infection can be as much as one pint (16 ounces), putting pressure on the adjacent body part or organ. A variety of bacteria, such as Staphylococcus aureus, Streptococcus pneumoniae, and Haemophilus influenzae, may cause empyema.
Risk Factors
Bacterial infection is the primary risk factor for empyema. Lung abscess, chest surgery, and injury or trauma to the chest are also risk factors for pleural empyema. Cholecystitis with contaminated bile is a risk factor for empyema of the gallbladder. People with chronic diseases may be more likely to develop empyema. Cancer may also contribute to empyema development.
Symptoms
Symptoms will vary based on the location of the empyema. Fever is almost always present. Sweating, especially at night, often occurs. Sharp or shooting pains, undesired weight loss, headache, and a general poor feeling may occur. For empyema in the pleural space or chest cavity, shortness of breath and difficulty breathing are usually evident. For empyema in the pelvic cavity, foul smelling pus is present. A rigid or very tight abdomen may be noted.
Screening and Diagnosis
Screening and diagnosis are based on symptoms and careful evaluation of the physical condition of the infected person and his or her complaints. Decreased breath sounds (heard through a stethoscope) are often noted if pleural empyema is present. Taking a sample of pus from the pleural space by using a needle or plastic catheter (thoracentesis) is sometimes done to look for the causative bacteria. The doctor will also investigate any complaints of pain. Radiology tests, including X-rays and computed tomography (CT) scans, are often used.
Treatment and Therapy
The primary goals of therapy are to cure the infection and to drain the pus if possible. Antibiotics are prescribed and may be given intravenously (in a vein), which requires hospitalization. If pleural empyema is the diagnosis, a chest tube inserted into the pleural cavity may be used to drain the pus from the body. In rare cases, a procedure to peel away part of the lining of the lung may be done so that the lung can inflate. In empyema of the gallbladder, surgery to remove the gallbladder may be indicated. Other surgeries may be necessary, depending on the site of the empyema.
Prevention and Outcomes
One can help prevent the development of empyema by treating infections promptly and using antibiotics appropriately.
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