Sarcoidosis is a disease in which nodules of immune cells form, primarily in the lungs but also in the skin or in the heart. While the lung symptoms are similar to those of tuberculosis, the etiology of the disease is unknown. It is currently assumed that causation is multifactorial, whereby certain environmental impacts and bacterial pathogens trigger sarcoidosis in genetically predisposed individuals. For example, there was a rise in the number of cases of sarcoidosis among firemen who were deployed during 9/11, due to the enormous dust burden to which they were exposed. Also, the bacterium responsible for causing acne is found in the pulmonary granulomas of many patients.
* This article was originally published here