Search for Mycobacterium paratuberculosis DNA in tissue from patients with sarcoidosis by enzymatic gene amplification.

The etiology of sarcoidosis has not yet been established, but several mycobacterial species have been implicated in the pathogenesis of this disease. We have used a nested primer polymerase chain reaction (PCR) specific for the IS900 Mycobacterium paratuberculosis insertion element to analyse paraffin-embedded mediastinal lymphoid tissue from 18 patients with pulmonary sarcoidosis verified by mediastinoscopy. Only the positive control contained M. paratuberculosis-specific DNA. The present study does not support a role for M. paratuberculosis in the pathogenesis of sarcoidosis. However, further studies are needed in order to clarify the possible role of other mycobacteria in this disease.