[Atypical forms of sarcoidosis].

Many atypical forms of sarcoidosis have been described. mediastinum-lung involvement, observed in 90% of the cases, may cause atypical manifestations: hemoptysis, chest pain, predominant pleural or proximal bronchial involvement. Diffuse "unpolished glass" images or air cavities may be observed on the chest x-ray. A rigorous diagnostic work-up is necessary for these atypical forms. Pathological confirmation is mandatory: non-caseous tuberculoid granuloma. A very wide range of extra-thoracic localizations have been described with variable clinical manifestations. In cases with no mediastinum-lung involvement, pathology data must be confronted with the notion of multiple organ dissemination to reach diagnosis.