Rare localisations of sarcoidosis, mainly neurological and cardiological ones are in the most cases seriously threatening whether functional or vital prognosis. They are often responsible for a delay in diagnosis or treatment. Concerning young patients, any unexplained neurological or cardiological manifestations should lead to consider the diagnosis of sarcoidosis. When histological evidence is not obtained, in particular in presence of central nervous system localisations. Systemic explorations such as pulmonary radiography, bronchoalveolar lavage, salivary glands biopsies should be performed. In most cases, these localisations will lead to corticotherapy, which, when revealing unsuccessfully, is associated with another immunosuppressive agent.