F-fluorodeoxyglucose positron emission tomography for relapsing polychondritis as a diagnostic approach and evaluation of disease activity.

A 60-year-old man presented with persistent cough and wheezing. The effect of inhaled corticosteroids and β2 agonists was temporary, and low grade fever, malaise and weight loss developed with a C-reactive protein level of 11.59 mg/dl and a white cell count of 10 460 cells/μl, while other manifestations such as otorhinolaryngological involvement were not observed. Tumour markers, anti-nuclear antibody and anti-neutrophil cytoplasmic antibodies were negative except for 780 U/ml of a soluble interleukin 2 receptor. Sputum culture and cytology were also negative. Near circumferentially thickened walls of the trachea and major bronchi were seen on chest radiographs and CT scans. 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) was thus performed as an investigation for malignancy; this revealed that 18F-FDG uptake was correspondingly distributed in the cartilages of the thickened airway walls and larynx (fig 1A). During an additional investigation, which was positive for serum anti-type II collagen antibody (>113 ELISA units (EU)/ml), deafness, tinnitus and bilateral ear swellings developed 1 month after 18F-FDG PET. A diagnosis of relapsing polychondritis (RP) was finally established based on clinical manifestations and the histological findings of the biopsy from the patient’s auricle.1 Treatment with systemic corticosteroids eliminated his symptoms and 18F-FDG uptake (fig 1B). Figure 1 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) images of the patient with relapsing polychondritis. 18F-FDG uptake found at relapsing polychondritis (RP) diagnosis (A) was eliminated after the treatment with systemic corticosteroids (B). ... RP is a rare inflammatory chondropathy and may not be readily diagnosed in the absence of specific otorhinolaryngological involvement.2 The characteristic image of 18F-FDG PET helps to establish an early diagnosis of RP and better understand the status and extent of the disease. 18F-FDG PET for RP is a powerful tool for the diagnosis and the evaluation of disease activity.