Sarcoid Dactylitis: worse than we "exPEcT".
Fiche publication
Date publication
octobre 2015
Auteurs
Membres identifiés du Cancéropôle Est :
Pr LIPSKER Dan
Tous les auteurs :
Matuszak J, Blondet C, Durckel J, Lipsker D, Sibilia J, Imperiale A
Lien Pubmed
Résumé
We report a didactic and typical case of distal bone sarcoidosis studied by 18 F-FDG PET/CT in a 34-year-old North-African man with mediastinal and cutaneous histologically proven sarcoidosis. Physical examination only revealed a painful swelling of the 4th and 5th fingers of the right hand and the 2nd , 3rd and 4th fingers of the left hand (A). X-rays showed characteristic pseudocystic lytic lesions limited to a few phalanges, and a grid appearance of the cancellous bone due to thickened trabeculae (B). Surprisingly, 18 F-FDG PET/CT revealed a striking bilateral 18 F-FDG uptake in almost all phalanges, all metacarpals and both ulnar heads (C). Bone involvement was particularly evident using a combination of CT-VRT (Volume Rendering Technique) and PET-MIP (Maximum Intensity Projection) images (D). Similar findings were observed in feet. PET/CT also showed intense 18 F-FDG uptake in mediastinal, axillary and inguinal lymphadenopathy. Steroids and methotrexate treatment was started. Sarcoidosis is a granulomatous non-caseating multisystem disease of unknown etiology. The prevalence of bone involvement has been estimated to 3%, frequently affecting distal and intermediate phalanges of hands and feet. Bone sarcoidosis is asymptomatic in about 50% of cases. The clinical presentation is a dactylitis with joint pain, soft-tissue infiltration and phalangeal swelling potentially evolving towards pseudo-clubbing or sausage-like fingers (1). Both clinical and radiographics features are highly specific. Hence, histologic confirmation is rarely required in patients with sarcoidosis. Magnetic resonance imaging may be useful for the differential diagnosis in patients with dactylitis, demonstrating marrow lesions that are radiographically occult, extension of granulomas beyond the cortex and periosseous soft-tissue involvement. Treatment is non-consensual because of BS poor response to steroids. 18 F-fluorodeoxyglucose (18 F-FDG) positron emission tomography/computed tomography (PET/CT) is a sensitive but not specific technique widely accepted for the clinical management of histologically-proven sarcoidosis, allowing complete morpho-functional cartography of inflammatory active localizations (2-3) also identifying occult sites. Accordingly, the exploration of extremities could be performed in patients with histologically-proven sarcoidosis underwent 18 F-FDG PET/CT to detect bone involvement earlier than the onset of clinical symptomatology or typical X-rays appearance. This article is protected by copyright. All rights reserved.
Référence
Arthritis Rheumatol. 2015 Oct 16