Ultrasonographic Evaluation of Sub-Clinical Synovitis in Juvenile Idiopathic Arthritis: The Disease Classification and Management.

Background: Ultrasonography (USG) is a perfect device for analyzing more than one joint in rather brief intervals of time and is well accepted by children with no harmful ionizing radiation, usually does not require sedation, and can be carried out without difficulty in an outpatient setting.

Purpose: To demonstrate the ability of ultrasonography (USG) in detecting clinical and subclinical synovitis in children with juvenile idiopathic arthritis (JIA) and compare the USG findings with clinical findings.

Methods: 20 patients with JIA diagnosed according to the ILAR criteria were include. A total of 208 joints were examined both clinically and ultrasonographically for detection of synovitis. The presence of subclinical synovitis detected by USG was sought and its effect on the classification of JIA was assessed. USG assessment was done using the High-Resolution Linear probe including both grey scale and Power Doppler assessment.

Results: The mean age of patients was 10.2 years with average disease duration of 5.9 months. A total of 49 joints (23.5%) had clinical synovitis and 59 joints (28.4%) had USG synovitis out of a total of 208 joints. A total of 14 joints had subclinical synovitis (8.8% out of the 159 clinically normal joints) upon USG. USG additionally brought about classifying three patients as having poly articular disorder who had been considered as oligo articular upon clinical examination.

Conclusion: USG assessment of subclinical synovitis in JIA patients is an essential component of classifying the disease and detects more joints with synovitis than clinical examination; however, both are complimentary and should be used in combination in all patients with JIA.