Musculoskeletal Ultrasound for Differentiating Rheumatoid and Gouty Arthritis

Rheumatoid arthritis (RA) and gouty arthritis (GA) are two common forms of joint inflammation that can present with very similar physical symptoms, making them difficult to tell apart early in the disease process. Accurate and early differentiation is crucial because the treatment strategies and long-term management for the two conditions are substantially different.

The primary purpose of this observational study is to evaluate the diagnostic performance of musculoskeletal ultrasound (MSUS) in distinguishing between RA and GA. Ultrasound is a safe, radiation-free imaging tool that can visualize joint inflammation and structural changes in real-time. This study utilizes a structured semi-quantitative scoring system (graded on a scale of 0 to 3) to systematically measure the severity of joint lining thickness (synovial hypertrophy) and active blood flow (power Doppler signal). It also checks for crystal-related deposits, such as tophi or the double contour sign, which are highly suggestive of gout.

Participants aged 18 and older with suspected or confirmed RA or GA who are referred for joint assessment at Assiut University Hospitals will undergo a standard clinical evaluation, routine laboratory testing, and an ultrasound examination of specific target joints (such as the wrists, hands, knees, and ankles). By comparing the ultrasound scores and specific structural findings between the two patient groups, the study aims to establish a reliable, standardized imaging approach to help physicians make faster, more confident diagnoses and initiate the correct disease-specific therapies sooner.