The Burden of Enthesitis, Inflammatory Arthritis and Tenosynovitis on Musculoskeletal Ultrasound in Systemic Lupus Erythematous: A Scoping Review

Objective The objective of this scoping review was to summarize the current literature on the burden of inflammatory arthritis, tenosynovitis, and enthesitis detected on musculoskeletal ultrasound (MSUS) in adult systemic lupus erythematosus (SLE) patients. Methods Systematic literature search was performed using Pubmed, Embase and Cochrane Library between January 1st 2015 and February 1st 2025, according to the PRISMA extension for scoping reviews. To be included, studies on the adult SLE population must have reported on either synovitis, tenosynovitis or enthesitis. Exclusion criteria were pediatric studies, rhupus-only studies, case series with less than 5 patients, review articles and conference abstracts. A pre-established standardized data collection sheet was used. Results The literature search found 24 articles that met inclusion criteria. Studies reported on inflammatory arthritis (n= 20), tenosynovitis (n = 16), and enthesitis (n = 7). Most studies were cross sectional (n = 20/24). Using criteria that were discriminatory for inflammatory enthesitis (power doppler and bone erosion), inflammatory enthesitis was found in SLE patients, and they were more common at the distal patellar, proximal patellar and quadriceps enthesis. In the general SLE population, studies on inflammatory arthritis and tenosynovitis found clinical arthritis in 18-38% of patients, MSUS arthritis in 33-55% of patients, subclinical MSUS arthritis in 9-21% of patients and tenosynovitis in 8-38% of patients. MSUS findings correlated with SLE disease activity indices, such as SLEDAI and BILAG. Conclusion Enthesitis may be a new musculoskeletal domain in SLE. MSUS can be useful in diagnosing tenosynovitis and subclinical inflammatory arthritis in SLE patients.