Objectives: Rheumatoid arthritis (RA) is a common autoimmune disease typically affecting joints symmetrically. A small number of patients develop unilateral and severely destructive wrist arthritis (DWA). The objective of our study was to characterise patients with this type of affection.
Methods: This was a retrospective cohort study of RA patients with positive RF/anti-CCP antibodies. Clinical characteristics, including, age, gender, disease duration, dexterity, occupational history, smoking status, and the number of prescribed DMARDs were recorded. Conventional radiographs were evaluated using the modified Sharp/van der Heijde scoring (mSS) method.
Results: We analysed our laboratory database of 1247 patients and identified 559 patients with a clinical diagnosis of RA. For 395 of the patients, radiographs of the hands were available for evaluation. 25 patients had extensive unilateral DWA, corresponding to a prevalence of 6.3% (25 of 395 patients). 11 patients were excluded due to incomplete data. Of the remaining 14 patients, 13 were female with a median age of 61 (33-83) years, and median disease duration of 18 (1-33) years. 8 of 11 (72.7%) patients were smokers; in three, smoking status was not known. 80% with known dexterity developed unilateral DWA in the dominant hand. Total mSS was significantly higher on the affected side (39, interquartile range 35.25-46.25) versus non-affected (13, IQR 3-23). MSS were not different if the carpal bones were excluded from scoring. Side of involvement (left vs. right), or dominant versus non-dominant hand, did not result in a different mSS.
Conclusions: Unilateral DWA is a rare variant of RA which predominantly affects women who smoke.