Resumo:
Objectives: To characterize patients with difficult-to-treat rheumatoid arthritis (D2T-RA) followed at a tertiary center in Northeastern Brazil, correlating disease activity indices with ultrasound findings using the US10 score.
Methods: This cross-sectional study was based on clinical examination, laboratory findings, medical record review and joint ultrasound evaluation. Nineteen women diagnosed with D2T-RA, defined according to EULAR 2021 criteria, were included between May and September 2025. Ten joints from the US10 score (proximal interphalangeal, metacarpophalangeal, radioulnar, and radiocarpal) were analyzed from each participant, considering inflammatory parameters — synovial proliferation, power Doppler, and tenosynovitis—and structural parameters — bone erosion and cartilage damage. Clinical, laboratory, and disease activity indices (CDAI, DAS-28), functionality (HAQ-DI), and fatigue (FACIT) were assessed. Non-parametric inference included Mann–Whitney U testing for group comparisons and Spearman’s rank correlation for association analyses (significance set at p < 0.05).
Results: Patients had a mean age of 55.8 ± 10.4 years, mean disease duration of 18.5 ± 7.2 years, and a predominance of Black race (63%). Hypertension and diabetes were frequent comorbidities (52.6% and 42.1%, respectively), and 31.6% had fibromyalgia or psychiatric disorders. Clinical scores showed moderate activity (CDAI 14.8 ± 7.6; DAS-28 3.74 ± 0.81) and elevated inflammatory markers (ESR 41.4 ± 31.2; CRP 11.7 ± 14.6). HAQ-DI (1.47 ± 0.56) and FACIT (23.9 ± 7.9) indicated functional limitation and fatigue. Ultrasound parameters revealed moderate inflammation and predominant structural damage (bone erosion 11.5 ± 7.8; cartilage damage 7.0 ± 3.7). Positive correlations were found between tenosynovitis by power Doppler and CDAI (p = 0.004), DAS-28 (p = 0.012), and VAS (p = 0.002), as well as between cartilage damage and the number of biologic agents used (p = 0.025). The mean EULAR-OMERACT index (1.84 ± 0.77) indicated residual synovitis.
Conclusions: Patients with D2T-RA presented long-standing disease, moderate inflammatory activity, and marked joint damage on ultrasound. The US10 score proved useful for detecting subclinical inflammation and quantifying structural damage, supporting its role as an objective tool for disease monitoring and therapeutic decision-making in this challenging condition.
