Ultrasound findings in palindromic rheumatism

We read the article by Mankia et al on the distinct ultrasound (US) imaging phenotype in palindromic rheumatism (PR) with great interest.1 The authors found characteristic US findings in PR during flares that differ from those observed in patients with early rheumatoid arthritis (RA) or anti-cyclic citrullinated peptide (CCP)+ arthralgia. US extracapsular inflammation (periarticular inflammation, subcutaneous or peritendinous oedema), in most cases without joint synovitis, is the most frequent US finding in PR. These findings disappeared after acute attacks. The authors concluded that this imaging phenotype of extracapsular inflammation is specific for PR and may be distinguished from that observed in RA or persistent arthritis. They also suggest that true US intrasynovial inflammation may predict future RA in these patients. …