Musculoskeletal ultrasound findings in first-degree relatives of rheumatoid arthritis patients

Aim of the work: To determine the frequency of subclinical joint and/or tendon affection using high resolution ultrasonography in healthy first-degree relatives (FDRs) of patients with rheumatoid arthritis (RA) and the relation to serological markers. Patients and methods: This work was conducted on 60 subjects with high risk of developing arthritis; healthy FDRs of patients with RA. Clinical assessment, laboratory investigations and high- resolution musculoskeletal ultrasound (MSUS) were done. Seven joints of the clinically dominant foot and hand had been evaluated by ultrasound in grayscale and Doppler flow employing the ultrasound 7 (US7) scoring system. The US7 score evaluated the following joints: wrists, metacarpophalangeal (MCP) II and III, proximal interphalangeal (PIP) II and III, and metatarsophalangeal (MTP) II and V, which had been examined for tenosynovitis/para-tenonitis, synovitis, and erosions. Results: Rheumatoid factor (RF) was positive in four FDRs (6.7%) had, two (3.3%) had positive anti-cyclic citrullinated peptide (anti-CCP) antibodies, MSUS positive findings had been identified in 31 FDRs (51.6%); of whom 18 (58%) had arthralgia. Synovitis by Gray Scale was the commonest finding, as it was recorded in 31 FDRs (51.6%), tenosynovitis/para-tenonitis was present in 2 (3.3%) FDRs. There were no erosions detected in all subjects. The wrist was the most frequently affected joint in 23 subjects (38.3%) on MSUS.RF gives the best AUC being (67%), followed by anti-CCP (52%), then the arthralgia. Conclusion: This work is in line with the notion of FDRs being pre-RA. MSUS serves as an effective screening instrument for detecting subclinical synovitis among at risk individuals.