TOPLINE:

Palindromic rheumatism flares commonly began with unilateral hand and shoulder involvement, and persistent inflammatory arthritis typically developed in the same joints previously affected by palindromic flares, according to findings from a single-center, longitudinal study.

METHODOLOGY:

• Researchers conducted a single-center longitudinal study in the UK, recruiting patients with palindromic rheumatism (positive or negative for anti-cyclic citrullinated peptide [anti-CCP] antibody) and anti-CCP-positive at-risk individuals with musculoskeletal symptoms but without palindromic rheumatism.
• They identified 63 patients with palindromic rheumatism whose disease progressed to persistent inflammatory arthritis (mean age at initial flare and progression, 51.5 years and 53.6 years, respectively).
• Demographic, clinical, and serologic data were collected every 3 months during the first year and annually thereafter.
• A palindromic rheumatism flare was defined as having two or more features of pain, swelling, and erythema in or around one or more joint regions that later normalized. Joints were categorized as being affected during the initial palindromic rheumatism flare, subsequent flares before progression to persistent inflammatory arthritis, or at progression (defined as having at least one persistent swollen joint).
• Comparisons were made between anti-CCP-positive patients with and without palindromic rheumatism who met the 2010 American College of Rheumatology and European Alliance of Associations for Rheumatology classification criteria for rheumatoid arthritis (RA) at progression.

TAKEAWAY:

• Among patients with palindromic rheumatism whose disease progressed to persistent inflammatory arthritis, 87.3% were anti-CCP-positive, 63.5% were rheumatoid factor (RF)-positive, and 61.9% were positive for both anti-CCP and RF. Among 48 patients with complete data on joints, 70.8% developed persistent inflammatory arthritis in at least one joint affected during any previous flare.
• During the initial flare, 47.9% of patients reported hand involvement, consisting of 16 unilateral and seven bilateral cases, and 33.3% reported shoulder involvement, comprising 11 unilateral and five bilateral cases.
• Prior involvement of a joint during a palindromic rheumatism flare was associated with an approximately twofold higher risk of developing persistent inflammatory arthritis in the same joint (odds ratio, 1.97; P < .001, after accounting for within-patient clustering and joint-specific risk).
• Among patients whose disease progressed to RA, those with palindromic rheumatism (n = 53) vs those without palindromic rheumatism (n = 151) had lower mean Health Assessment Questionnaire scores (0.79 vs 1.12; P = .027) and higher mean swollen joint counts (28-swollen joint count, 4.1 vs 3.2; P = .045), despite having similar Disease Activity Score in 28 joints using C-reactive protein or erythrocyte sedimentation rate.

IN PRACTICE:

“In patients with PR [palindromic rheumatism] who progress to PIA [persistent inflammatory arthritis], arthritis mostly develops in joints previously inflamed during PR flares, emphasizing the importance of thorough joint evaluation during PR for surveillance of future persistent joint involvement,” the authors wrote.

SOURCE:

This study was led by Didem Sahin, MD, Leeds Institute of Rheumatic and Musculoskeletal Medicine, University of Leeds in Leeds, England. It was published online on April 9, 2026, as a short report in RMD Open.

LIMITATIONS:

Potential recall bias may have existed from patient-reported initial flares. Joint data for some patients were incomplete. The study had limited power for subgroup comparisons because of small sample sizes.

DISCLOSURES:

Financial support for this research was provided by the National Institute for Health and Care Research Leeds Biomedical Research Centre, Leeds Teaching Hospitals National Health Service Trust. One author disclosed receiving a research grant, speaking fees, and support for attending meetings from various sources outside the submitted work. Another author disclosed receiving research grants and consultancy fees or honoraria from multiple sources.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.