What's in a relationship? Sarcoidosis and tuberculosis

The relationship between the two granulomatous diseases sarcoidosis and tuberculosis is reviewed. Data from 14 published case series are presented in the form of a figure which indicates that case series collected earlier in time and with a high proportion of non-white patients show a higher prevalence of tuberculosis. This high prevalence was also found in other chronic diseases such as diabetes and rheumatoid arthritis. The more frequent presence of mycobacteria in sarcoid than in control tissue, the parallel changes in the prevalence of sarcoidosis and tuberculosis in a community and the presence of myocbacteria on culture if pursued with sufficient aggression, are consistant with a mycobacterial aetiology. Recent developments in the immunology of the two diseases are reviewed.