ABSTRACT
The nuclear medicine techniques represent an important role in infections and inflammation's evaluation. 18-fluorode soxyglucose [18F-FDG] is a tracer of glucose metabolism, recently produced in Morocco, which provides functional sensitive and high resolution images thanks to Positron Emission tomography [PET]. The indications of FDG-PET in internal medicine include the diagnosis management of certain inflammatory diseases, vasculitis of large vessels, such as temporal arteritis, especially in its systemic presentation, and Takyasu's arteritis. It is also useful for staging sarcoidosis, for differential diagnosis and the therapeutic's evaluation in multiple myeloma. The 18-FDG PET is the most effective for the diagnosis of paraneoplastic syndromes, or carcinomas of unknown primary. In case of fever of unknown origin, it facilitates the identification of the site of the infection and guides investigations conducting to the confirmation of the diagnosis. All, situations frequently found in internal medicine. This article will focus on the role of 18-FDG PET in the pathology specific to internal medicine. However, large scale prospective studies are needed before incorporating FDG-PET in clinical routine, because it is expensive and not available in our country