Empyema is one of many respiratory conditions, the symptoms of which may be similar to the asbestos
cancer commonly known as mesothelioma and/or pleural effusion
; indeed, it is the result of a build-up of fluid between the lung surface and the pleural membrane itself, and therefore can result in the same type of chest pain
and shortness of breath. It is however a different kind of affliction that is not necessarily related to carcinoma.
Unlike pleural effusion, which is an excessive build-up of normal lymphatic fluids, empyema is the build up of pus in the same space. This is an important distinction, because unlike lymphatic fluid, pus is the by-product of bacterial infections that is produced during the inflammatory response by the immune system.
Pus is made up of dead white blood cells and a protein fluid called liquor puris. When the immune system detects a harmful foreign, or exogenous pathogen, it responds by moving blood plasma and infection-fighting white blood cells (technically known as leulocytes) to the affected tissues. This results in inflammation, which is the immune system's attempt to destroy the invader.
Empyema is the result of this type of inflammation in response to a harmful exogenous pathogen in the pleural cavity. Most often, it is caused by pneumonia, but may also be a response to asbestosis.
Because of the pressure, the lungs are unable to expand properly, which is why those suffering from the condition are often short of breath and experience chest pains. Patients with empyema often develop fever, chills, shakes and/or malaise. Untreated empyema can result in septic shock.
In addition to the symptoms which are common to many respiratory conditions, people suffering from empyema may also suffer from coughing, producing blood or greenish-brown sputum. Fatigue, dehydration, halitosis (bad breath) and unexplained weight loss are also symptoms; in some cases, victims develop a fever that may run as high as 105 degrees Fahrenheit. In extreme cases, patients fall into a coma.
Empyema may ultimately kill the patient if not treated promptly. Because the bacteria that causes the infection is carried in the bloodstream, empyema can spread to all parts of the body. The pus may also build up to the point that a rupture occurs and pus enters the airways.
In addition to pneumonia, empyema may also occur as the result of a chest wound, surgery, or a ruptured esophagus (the passage for food and liquid).
Empyema goes through three major stages:
- Acute Stage: this is the initial stage in which pus begins to accumulate inside the pleural cavity. This is also known as the exudative stage, during which levels of glucose and pH remain normal.
- Middle Stage: the pus starts to increase in viscosity, becoming fibrous. This is technically called the fibrinolytic stage; as fluids begin to coagulate, an adhesive network starts to form around the lungs.
- Chronic Stage: the lungs become calcified, or encased in a thick, fibrous substance. Medical personnel refer to this as the organizing stage.
If a preliminary examination indicates serious problems - i.e., if there are signs of decreased respiratory function or abnormal rubbing sounds detected when listening through a stethoscope, if the patient has unexplained fever, the physician will order a chest x-ray, and follow this up with thoracentesis - the insertion of a needle into the chest through which fluid can be extracted. The fluid will then be examined for pH and glucose levels as well as the presence of infectious agents (i.e., bacteria). A computed tomography (CT) scan may be ordered to confirm any findings up to that point.
The first and most important step is to relieve pressure on the lungs by aspirating, or draining the fluids out of the pleural cavity. Like thoracentisis, this involves the insertion of a tube in order to drain the pus away from the area.
Since the cause of empyema is a bacterial infection, antibiotics are usually prescribed, particularly if the condition is still in the exudative stage.
If the empyema has reached the organizing stage, surgical treatment may be necessary. This procedure is called decortication, and consists of cutting and peeling away some part of the lung lining to relieve pressure and allow the lungs to expand normally.
In normal cases of empyema due to bacterial infections, if the condition is treated in the early stages, prognosis is generally good; no permanent lung damage occurs.
Pleural Calcification and Asbestos Disease
When the pleural lining has calcified, the lungs can no longer expand properly. While this is the third stage of empyema, it is also caused by asbestos exposure
It is important to understand that asbestos exposure, by itself, does not cause empyema. The topic is presented here because of unrelated parallels between empyema and various asbestos-related diseases. Malignant mesothelioma, which is a carcinoma that spreads in a sheet-like manner rather than a lump, can also reduce the lungs' ability to expand; however, technically, this is not the same as calcification.
Asbestosis on the other hand is known to be a cause of pleural calcification, although this is rare. These calcifications are typically small spots on the lungs, measuring under 4 cm in diameter. Talcosis - exposure to talc mixtures, which is frequently contaminated with asbestos fibers - produces virtually identical results in a radiologic exam.
Because of the parallel symptoms between empyema, asbestosis
and pleural mesothelioma
, it is important to get a second opinion if you have symptoms. Usually, a mesothelioma diagnosis can only be confirmed beyond all doubt with a biopsy, or sample of affected lung tissue. In any sort of lawsuit relating to asbestos, a common defense is to deny that the plaintiff has mesothelioma or asbestosis at all, but something that only appears to be the said illness. In order to successfully win such a lawsuit, it is to the plaintiff's advantage to have at least two concurring medical opinions and a pathologist's findings from a biopsy.
- Wikipedia. "Empyema"
- Health-Cares.net. "What Are The Symptoms of Empyema?"
- Tobler, Marc, MD. "Empyema."
- Mason RJ, et. al. Murray and Nadel's Textbook of Respiratory Medicine.
- Ahmed RA, et. al. "Thoracic Empyema."