Cardiac Sarcoidosis: Causes

The exact cause of sarcoidosis is unknown.

What Causes Cardiac Sarcoidosis?

We know that African American are three to four times more likely to develop sarcoidosis than Caucasians, and may have more severe disease. The granulomas of sarcoidosis appear to be the result of an immune system response to an unidentified trigger. Researchers are not certain as to whether that trigger could be an environmental exposure to a chemical or linked to an organism, such as a bacteria or virus, or if there is another unknown cause. Some chemicals in the environment, such as beryllium, aluminum and zirconium, can cause lung disease that is similar to sarcoidosis, but it is unproven as to whether these are a factor in sarcoidosis. The damage that is done to tissues and organs such as the heart is a result of the bodies immune system trying to destroy the “foreign” sarcoidosis.

Some studies also indicate that there is a genetic (inherited) factor in sarcoidosis. Genetic mutations in white blood cell proteins (called human leukocyte antigens, or HLA) as well as chemicals that control inflammation (called cytokines) have been linked to sarcoidosis, including cardiac sarcoidosis.

Some experts say that both genetic and environmental factors may play a role in cardiac sarcoidosis. A genetically susceptible person may be more likely to react to environmental triggers and develop the disease.

The percentage of people with sarcoidosis who have been diagnosed with cardiac sarcoidosis has increased dramatically in recent years. However, experts say that this is more likely an improvement in diagnostic techniques than an increase in disease prevalence.

Researchers are continuing to study this little-understood disease. Learning more about the cause of sarcoidosis will lead to improvements in diagnosis and treatment.