[Sarcoidosis of the upper respiratory tract]

Sarcoidosis is a non-caseating granulomatous disease of unknown origin, principally affecting the respiratory tract.

Sarcoidosis of the upper respiratory tract (SURT) includes sino-nasal sarcoidosis (SNS) and pharyngo-laryngeal sarcoidosis (PLS). SURT may be isolated or, more often, part of multisystemic sarcoidosis. Its clinical symptomatology is protean and non specific. The natural history, course and prognosis are poorly understood and unpredictable. The treatment has not yet been standardised and the long-term therapeutic results are often disappointing.

In this work, we try to make a synthesis of our experience and publications, and the data in the existing international literature, to improve the diagnosis and therapeutic management of SURT. The usefulness of both morphological and functional imaging techniques, in particular 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET/CT), is evaluated for use in the management of the severe phenotypes of sarcoidosis such as SURT.

Even if guided biopsy remains necessary for confirmation of SURT, medical imaging plays an important role in the management of this disease: CT imaging allows the description of SNS and classification into two stages that correlate well with the severity, reversibility and course of the sino-nasal involvement, 18F-FDG PET/CT, providing a complete morpho-functional mapping of active inflammatory lesions, could be a useful technique in patients with biopsy-proven SURT, for both diagnosis and follow up of medical treatment.