Pos0532 global ultrasound synovitis score may reflect development of chronic post-chikungunya rheumatism

Background Chronic musculoskeletal (MSK) symptoms such as arthralgia and arthritis develop in up to half of patients after acute chikungunya virus (CHIKV) infection. While MSK complaints are common during the acute infection, chronic post-CHIKV rheumatism represents a more severe outcome and is usually assessed by joint counts, laboratory markers and patient-reported outcomes (PROs). Ultrasound (US) may be a practical tool for predicting and confirming the development of chronic CHIKV. Objectives To evaluate the clinical relevance of MSKUS findings in post-chikungunya rheumatism. Methods 80 patients with acute CHIKV infection were enrolled in a prospective cohort study in Jaén, Peru. Clinical exam, US scans using grey-scale and power Doppler (PDUS), and serum inflammatory markers were performed at inclusion and at 3-month follow-up. Patients completed the RAPID3 outcome assessment and a MSK stiffness questionnaire. Joint counts and PDUS scans included 20 pairs of joints. Global synovitis and tenosynovitis scores were calculated following the EULAR-OMERACT recommendations for rheumatoid arthritis (GLOESS). Results 59 patients (mean age 35 years, 68% female) were assessed both in the acute infection stage and at 3-month follow-up. 21 patients (35%) met strict criteria for defining chronic CHIKV rheumatism with a mean 4.4 (±2.2) tender joints and RAPID3 scores >6. In the acute infection phase, global PDUS synovitis and tenosynovitis scores correlated moderately with tender joint count and with pain severity, joint stiffness and RAPID3 scores, but were not strongly predictive of patients who went on to develop chronic arthralgia. After 3 months, global PDUS synovitis scores correlated more strongly with tender joint count (r=0.53, p<0.0001), pain severity (r=0.60, p<0.0001), joint stiffness (r=0.53, p<0.0001) and RAPID3 scores (r=0.60, p<0.0001) (Table 1). Conclusion Global PDUS synovitis and tenosynovitis scores may be an objective measure of disease severity in patients developing chronic CHIKV rheumatism. Further validation with longer-term follow-up is needed. Table 1. Correlation of synovitis and tenosynovitis PDUS scores with clinical examination and patient-reported outcomes (n=59). Period Assessment Variable Synovitis correlation P-value Tenosynovitis correlation P-value Inclusion Clinical exam Tender joint count 0.35 0.0068 0.30 0.0210 MSK stiffness Severity score 0.41 0.0011 0.36 0.0048 RAPID3 Disability index 0.39 0.0024 0.33 0.0119 Pain severity 0.36 0.0052 0.29 0.0277 Patient’s global health 0.35 0.0060 0.21 0.1045 Overall RAPID3 score 0.42 0.0010 0.31 0.0187 Month 3 Clinical exam Tender joint count 0.53 <.0001 0.52 <.0001 MSK stiffness Severity score 0.54 <.0001 0.62 <.0001 RAPID3 Disability index 0.48 0.0001 0.35 0.0070 Pain severity 0.60 <.0001 0.56 <.0001 Patient’s global health 0.56 <.0001 0.59 <.0001 Overall RAPID3 score 0.60 <.0001 0.57 <.0001 REFERENCES: NIL. Acknowledgements: NIL. Disclosure of Interests Hugh Watson Shareholder of: Sanofi, Employee of: Sanofi, Evotec, Juana del Valle Mendoza Grant/research support from: Sanofi, Evotec, Wilmer Silva Caso Grant/research support from: Sanofi, Evotec, Miguel Aguilar Luis Grant/research support from: Sanofi, Evotec, Andrea NIzzardo Employee of: Evotec, Giulia Calusi Employee of: Evotec, Marie Mandron Employee of: Sanofi, Evotec, Maria-Antonietta D’Agostino Consultant of: Evotec.