Pleural empyema is a condition in which pus accumulates in the space between the lungs and the inner surface of the chest wall (pleural cavity). Empyema is often associated with pneumonia, but can also develop after chest surgery or trauma.
What is Pleural Empyema?
Unlike pleural effusion, which is a buildup of fluid in the pleural cavity, pleural empyema is characterized by a collection of pus that appears cloudy when drained. The condition is caused by an untreated bacterial infection in lung tissue, which can spread to the pleural cavity and create pockets of pus. Unlike effusions, pleural empyema also involves an increase in white blood cells, with many neutrophils present in the pus.
Two causes of pleural empyema
The lungs and the inside of the chest are lined with a smooth layer called the pleura. These layers are almost in contact with each other, but separated by a thin space (pleural cavity) filled with a small amount of lubricating fluid called pleural fluid.
Pleural fluid can sometimes accumulate and become infected, forming pus. This thickens and causes the areas of the pleura to stick together, creating pockets of pus.
The condition can become more severe, with more pockets of pus, and a thick layer of debris covering the outer layer of the lungs. These sediments prevent the lungs from expanding properly. 
There are many causes leading to the condition of pleural empyema, such as:
- Having lung infections such as pneumonia, pleurisy, pulmonary edema, fungal pneumonia, and cancerous lung infections.
- Having mediastinal diseases such as bronchial exploration, esophageal exploration, etc.
- Chest diseases such as rib inflammation, breast compression, etc.
- Diseases under the diaphragm such as liver compression, peritoneal inflammation, etc. Blood infection.
- The most common bacteria causing pleural empyema are Klebsiella pneumoniae, Staphylococcus aureus, and others like fungi or amoeba can also cause this condition.
Symptoms and Diagnosis of Pleural Empyema
Pleural empyema needs to be diagnosed and treated early to avoid serious consequences for the patient’s health.
Diagnosing the disease relies on clinical symptoms and specific laboratory tests, including:
Patients with a history of inflammatory lung or adjacent organ diseases.
Sudden high fever, sometimes prolonged low-grade fever (often seen in immunocompromised individuals or those who have taken antibiotics).
Persistent cough or coughing up purulent sputum.
Painful and damaged area on the affected side of the chest.
Signs of dehydration (dry skin, reduced urine output, etc.), weight loss, anemia.
The affected side of the chest may show swelling, limited mobility, dullness to percussion, and decreased breath sounds.
Needle aspiration reveals turbid, yellow, green, or brown-colored pus with a foul odor or none.
The blood test shows an increase in white blood cell count, which may indicate anemia.
Chest X-ray reveals an image of pleural effusion.
Ultrasound of the pleural cavity shows pleural effusion with increased density and a snowstorm-like appearance.
CT scan is necessary to determine the location, extent of damage, and the path leading to the abscess of pleural membrane.
Examination of the pleural fluid shows the presence of numerous polymorphonuclear leukocytes and degenerative cells.
Bacterial culture of the pleural fluid and blood is performed to identify the causative agent.
It is important to differentiate pleural empyema from other diseases with similar symptoms (such as pleural effusion, etc.).
Generally, pleural empyema does not lead to permanent lung damage.
How is pleural empyema treated?
Patients diagnosed with pleural empyema need to be treated at a hospital that is capable of placing a chest tube.
If there is severe infection, septic shock, or respiratory failure, treatment should be administered in the intensive care unit.
The purpose of treatment is to clean the infected area in the pleural cavity by the following methods:
Early drainage of the empyema and daily pleural lavage.
High-dose antibiotics and systemic antibiotic therapy for 4-6 weeks.
The following issues should be noted:
Monitor closely and ensure adequate nutrition and hydration. Pay attention to coexisting conditions during examination and treatment and provide appropriate treatment. Perform physical therapy to early restore respiratory function.
Antibiotics are chosen based on the results of antibiotic susceptibility testing. Prior to that, patients may receive two types of antibiotics combined by intravenous or intramuscular injection.
After the treatment protocol is established, antibiotics should be administered early at a high dose via intravenous route for rapid effectiveness.
The medication should only be discontinued after one week of normal temperature and stable blood formula.
The following antibiotics can be used:
- Penicillin G 10 – 50 million units, divided into 3-4 times per day for intravenous infusion, combined with an Aminoglycoside antibiotic such as Gentamicin (3-5mg/kg per day intramuscular injection once) or Amikacin (15mg/kg per day intramuscular injection once).
- Substitute Penicillin G with Amoxicillin + Clavulanic acid or Ampicillin + Sulbactam if Betalactamase-producing bacteria are suspected (dose 3-6g/day).
- Use third-generation Cephalosporin if Gram-negative bacteria are suspected, combined with Aminoglycoside antibiotics with the same dose as above.
- Combine Beta-lactam + Clavulanic acid group with Metronidazole (1 – 1.5g/day, divided into 2-3 times for intravenous infusion) if anaerobic bacteria are suspected.
- For hospital-acquired pneumonia with septicemia, Ceftazidime (3-6g/day divided into 3 times) or Piperacillin + Tazobactam (4.5g 3 times per day) can be used if there is no antibiotic susceptibility testing result. Adjust antibiotics according to clinical progression and antibiotic susceptibility testing results.
- If Staphylococcus is suspected, use Oxacillin 6-12g/day or Vancomycin 1-2g/day, which can be combined with other antibiotics.
- If amoebiasis is suspected, use Metronidazole 1.5g/day, divided into 3 times for intravenous infusion, combined with other antibiotics.
- Note: Patients using Aminoglycoside antibiotics need to have their blood creatinine level tested twice a week.
Pleural effusion drainage
This method is applied in cases of pleural effusion that can be seen with the naked eye, with multi-nucleated leukocyte degradation, stained specimens showing bacteria, pH below 7.2, and glucose below 60mg/dL.
Be cautious when using this method for patients with coagulation disorders, small or near-central abscesses.
The duration of catheter placement should be 5-10 days. It should not be placed for too long as it can increase the risk of infection from the outside into the pleural cavity. If the fluid is purulent and thin, it is necessary to perform thoracentesis every 2 days.
Remember to perform daily lavage of the pleural cavity through the drainage tube using 0.9% NaCl until the fluid is clear. Do not perform lavage if there is bronchopleural fistula – pleural membrane (patients may cough or sputter during lavage).
Inject Streptokinase into the pleural cavity: After lavaging the pleural cavity, if feasible, inject 300,000 units of streptokinase into the pleural cavity once a day for 5 consecutive days, mixed with 100ml of 0.9% Sodium chloride to facilitate drainage of the effusion.
Indications for removing the drainage tube:
X-ray or ultrasound shows no more effusion. The pleural effusion drainage is clear and there is no more pus. Note that if the drainage tube has been placed for more than 10-14 days and there is still pus, a new drainage tube must be inserted.
If the fever is over 38°C, additional Paracetamol should be given to reduce the fever.
Supplement the patient’s nutrition through a proper diet.
Provide oxygen therapy to the patient if there is respiratory failure.
Treat septic shock if present.
For alcohol-addicted patients, high doses of Vitamin B1 and B6 should be administered.
Provide fluid and electrolyte replacement if necessary.
It is important to encourage the patient to start respiratory function rehabilitation early (1 day after placing the drainage tube) to help drain the pus more easily and prevent adhesion of the lung membrane.
Johnny Jacks was born in 1985 in Texas, USA. He is the founder of Good Health Plan and is passionate about helping people improve their health and physical well-being. With over a decade of experience working in the healthcare industry, he currently works at Goodheathplan.com – a blog that shares knowledge on beauty and health.