Tuberculosis is the most frequent cause of fever from unknown etiology. On the other hand, mediastinal tuberculous adenopathy (TBM), without associated pulmonary affection is a rare form of presentation among adults, generally evolving with sustained fever until a thoracic radiology is performed showing mediastinal enlargement. We present a case which started as fever from unknown etiology (FUE), given that, according to the thoracic radiology performed one month after the onset of fever, no mediastinal affection was observed.