The utility of FDG-PET/CT imaging in the evaluation of multicentric reticulohistiocytosis

Abstract

Introduction:Multicentric reticulohistiocytosis (MRH) is a rare histiocytic disorder that involves the skin, joints, and visceral organs.Case presentation:We report a 67-year-old woman with MRH who presented with a 2-years history of polyarthralgia and skin nodules. Her symptoms were an inflammatory polyarthropathy with punched-out lesions of the distal interphalangeal (DIP) joints of both hands. Doppler ultrasonography of the hands showed large bone erosions with power Doppler signals in the DIP joints. 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) demonstrated increased FDG uptake in cutaneous papules surrounding the affected joints, suggesting an inflammatory process. There was no evidence of malignancy. Biopsy samples of skin nodules exhibited dermal infiltration with CD68-positive histiocytes and multinucleated giant cells. The patient was diagnosed with MRH and treated with combination therapy comprising a steroid (prednisolone), tacrolimus, methotrexate, and infliximab, which resulted in clinical improvement. Following infliximab treatment, there was a significant decrease in a bone resorption marker (tartrate-resistant acid phosphatase 5b: TRACP-5b), suggesting that tumor necrosis factor-α targeting therapy may inhibit osteoclast formation and resorption activity in patients with MRH.Conclusion:MRH is a progressive destructive arthritic condition, and early diagnostic and therapeutic strategies are necessary to improve the outcome. FDG-PET/CT and joint ultrasonography might be noninvasive imaging modalities that could help diagnose MRH.

Multicentric reticulohistiocytosis: A case report with response to adalimumab

“…Of note, in a case report by Asano et al, when Doppler ultrasound revealed large bone erosions, the authors obtained an F‐fluorodeoxyglucose positron emission tomography/computed tomography (FDG‐PET/CT) with results suggesting an inflammatory process; biopsy ultimately helped establish the diagnosis of MRH. Although age‐appropriate malignancy screening with relevant imaging should be part of any MRH work‐up, this report highlighted the utility in joint ultrasonography as a helpful noninvasive imaging modality in diagnosing MRH 7 …”

Case Report: Multicentric Reticulohistiocytosis Associated With Posterior Mediastinal Adenosquamous Carcinoma, Antinuclear Antibody Positivity and Lupus Anticoagulant Positivity

“…Due to the background of negative tumour markers in routine serum tests and the lack of symptoms, it can be difficult to detect this type of malignancy by chest HRCT, especially by inexperienced clinicians. In recent years, the application of FDG-PET/CT in MRH has attracted increasing attention (27)(28)(29). FDG-PET/CT is a potentially useful way to detect and evaluate the grade of inflammatory involvement of MRH and to assess the possible associations with malignant neoplasms, as FDG is easily taken up by granulomas and inflammatory cells.…”

Reticulohistiocitosis multicéntrica: una gran simuladora dentro de la Reumatología

“…Otros compromisos detallados son los de la mucosa oral 3,20 , glándulas salivares mayores 4,15 , nódulos submucosos hipofaríngeos 4,21 , nódulos laríngeos 4,22 y nódulos hepáticos 23 . Se han informado casos aislados de RHM con fenómeno de Raynaud y esplenomegalia 4,24 .…”