To date, the causes of sarcoidosis (Besnier-Boeck-Schaumann disease) are not clearly identified. Different factors could come into play and explain the appearance of this systemic inflammatory disease, characterized by the formation of granulomas in different organs.
Genetic factors may be a possible cause of sarcoidosis: in 1 out of 50 cases, several members of the same family are affected by the disease. In addition, some genetic mutations increase the risk of developing sarcoidosis.
Ethnic and geographical factors
Highly variable incidences across countries and ethnic groups indicate that geographic and ethnic factors also play a role in the occurrence of sarcoidosis. For example, the disease is more prevalent in some populations (eg Black-African Americans) and in some countries (eg Sweden or Iceland).
Toxic substances absorbed by the respiratory route
As in 90% of cases, sarcoidosis has pulmonary involvement (pulmonary sarcoidosis), a possible cause of the disease is the inhalation of "toxic" substances by the lungs. Some scientists assume that these inhaled substances activate the immune system, causing the appearance of granulomas typical of sarcoidosis.
The lungs can be affected from the beginning of the onset of the disease, but also as it evolves.
It has not yet been established which inhalants could be responsible for sarcoidosis. But different triggers could be involved, such as: chemicals, fine particles, bacteria, viruses, allergenic substances.