Power Doppler ultrasound in the evaluation of hand joints in rheumatoid arthritis patients in clinical remission: Association with composite index scores and functional status

Background: Evaluation of remission in Rheumatoid Arthritis (RA) largely relies on composite scores based on clinical and laboratory assessments however, patients can fulfill clinical remission criteria as defined by composite scores, yet still have evidence of synovitis detectable on imaging. Aim of the work: To evaluate hand and wrist joints in patients with RA in clinical remission using power Doppler (PD) ultrasonography and to study the association between ultrasonographic findings and composite index scores. Patients and methods: This study was conducted on 50 RA patients in clinical remission. Ten matched healthy subjects were included as control. The modified health assessment questionnaire (MHAQ) was assessed in the patients; disease activity was calculated using a composite index score including disease activity score (DAS28) and clinical disease activity index (CDAI). Ultrasonographic assessment of the hand and wrist joints was performed. Results: The mean age of the patients was 50.9 ± 9.2 years, disease duration was 10.6 ± 5.5 years and were 38 females and 12 males. The mean DAS28 was 2.3 ± 0.3. On ultrasonographic examination, 14 (28%) patients had normal synovium, while 18 (36%) showed synovial hypertrophy without evidence of inflammation and 18 (36%) had PD signals. DAS28 was higher in patients with PD signals (2.36 ± 0.3) compared to those without synovitis (2.3 ± 0.28). There was a significant correlation between PD activity and CDAI (p = 0.005), MHAQ (p = 0.002) and disease duration (p = 0.023). Conclusion: Power Doppler ultrasound can detect residual inflammation in RA patients in clinical remission and its scores were signficantly associated with the clinical disease activity index and functional status. Keywords: Rheumatoid arthritis, Remission, Disease activity score-28 (DAS28), Clinical Disease Activity Index (CDAI), Power Doppler ultrasonography