To the Editor:
We read with great interest the paper by Owada, et al1 that evaluated the role of 18F fluorodeoxyglucose positron emission tomography (FDG-PET) in assessing activity of myositis. The authors found that FDG-PET was highly specific (97%) in discriminating patients with myositis from unaffected controls. However, the sensitivity of FDG-PET was only 33%. In contrast, in a study published in 20122, we found that FDG-PET was 75% sensitive and 100% specific in distinguishing patients with active myositis from unaffected controls.
How can these discordant findings be reconciled? The main reason for such discrepancies lies in the …
Address correspondence to Dr. C. Salvarani, Rheumatology Unit, Arcispedale Santa Maria Nuova, Viale Risorgimento 80, 42123 Reggio Emilia, Italy. E-mail: Salvarani.carlo{at}asmn.re.it