Ultrasound to identify systemic lupus erythematosus patients with musculoskeletal symptoms who respond best to therapy: the US Evaluation For mUsculoskeletal Lupus longitudinal multicentre study

Objectives. To determine whether SLE patients with inflammatory joint symptoms and US synovitis/tenosyovitis achieve better clinical responses to glucocorticoids compared with patients with normal scans. Secondary objectives included identification of clinical features predicting US synovitis/tenosynovitis. Methods. In a longitudinal multicentre study, SLE patients with physician-diagnosed inflammatory joint pain received intramuscular methylprednisolone 120 mg once. Clinical assessments, patient-reported outcomes and bilateral hand/wrist USs were collected at 0, 2 and 6 weeks. The primary outcome (determined via internal pilot) was the early morning stiffness visual analogue scale (EMS-VAS) at 2 weeks, adjusted for baseline, comparing patients with positive (greyscale >= 2 and/or power Doppler >= 1) and negative US. Post hoc analyses excluded FM. Results. Of 133 patients, 78 had a positive US. Only 53 (68%) of these had one or more swollen joint. Of 66 patients with one or more swollen joint, 20% had a negative US. A positive US was associated with joint swelling, symmetrical small joint distribution and serology. The primary endpoint was not met: in the full analysis set (N = 133) there was no difference in baseline-adjusted EMS-VAS at week 2 [-7.7 mm (95% CI -19.0, 3.5); P = 0.178]. After excluding 32 patients with FM, response was significantly better in patients with a positive US at baseline [baseline-adjusted EMS-VAS at 2 weeks -12.1 mm (95% CI -22.2, -0.1); P = 0.049]. This difference was greater when adjusted for treatment [-12.8 mm (95% CI -22, -3); P = 0.007]. BILAG and SLEDAI responses were higher in US-positive patients. Conclusion. In SLE patients without FM, those with a positive US had a better clinical response to therapy. Imaging-detected synovitis/tenosynovitis may be considered to decide on therapy and enrich clinical trials.

Automated summary

In SLE patients without fibromyalgia, those with positive ultrasound (US) results showed better clinical response to glucocorticoid therapy. Imaging-detected synovitis/tenosynovitis may be considered to guide therapy decisions and improve outcomes in clinical trials.