Empyema is a collection of pus which is found in the pleural space (the cavity between the lung and the membrane that surrounds it). It is usually caused by a bacterial infection of the lungs.

Its development can be divided into three phases:

1) An acute phase- in which the body cavity fills with a thin fluid containing some pus

2) A second stage- in which the fluid thickens and a fibrous coagulation protein (fibrin) begins to accumulate within the cavity and

3) A third or chronic stage in which the lung or other organ is encased within a thick covering of fibrous material.

Causes

Empyema is caused by an infection that spreads from the lung and leads to an accumulation of pus in the pleural space. Actually the infected fluid can puts pressure on the lungs which causing shortness of breath and pain. However, it is most commonly caused by pneumonia. The same kinds of bacteria that cause brain abscesses can cause subdural empyemas.

The most common organisms that cause empyema are the bacteria name as Streptococcus pneumoniae, Haemophilus influenzae, and Staphylococcus aureus. S. aureus. Among them last three bacteria is the most common cause in all age groups which accounting for 90% of cases of empyema in infants and children. Pelvic empyema in women is most often caused by Bacteroides strains or Pseudomonas aeruginosa. In elderly, chronically ill, or alcoholic patients, empyema is often caused by Klebsiella pneumoniae species of bacteria.

Symptoms

In empyema thoracis, patients usually exhibit symptoms of pneumonia, including fever, cough, fatigue, shortness of breath, and chest pain. There is a dull percussion note and reduced breath sounds on the affected side of the chest. Chest x-ray shows a pleural effusion, often with a lateral bulge and pleural thickening. Ultrasound confirms the size and location of the pocket of pus and the presence of fibrin aggregates.

In severe cases, the patient may become dehydrated, cough up blood or greenish-brown sputum, run a fever as high as 105deg;F (40.6deg;C), or fall into a coma.

Treatment

In the early phase of empyema, an effusion is present. If the effusion is large, treatment is directed toward removal of the fluid. This can be accomplished by drawing off the fluid under local anesthesia by inserting a small catheter into the pleural space.

Antibiotics are prescribed to control the infection. In the case or an empyema in the area surrounding the brian, a lumbar puncture may be required as would extensive blood testing and culturing to determine the condition.