FRI0580 ULTRASONOGRAPHY SCORE CORRELATES WITH DISEASE ACTIVITY IN JUVENILE IDIOPATHIC ARTHRITIS – ENTHESITIS RELATED ARTHRITIS – A CROSS SECTIONAL OBSERVATIONAL STUDY FROM INDIA
Authors: pillai harikrishnan velayudhan, Rasmi Ranjan Sahoo, Saumya Ranjan Tripathy, Urmila Dhakad, Puneet Kumar, Anupam Wakhlu, Siddharth Kumar Das
Journal: Annals of the Rheumatic Diseases (2019)

<h3>Background</h3> Enthesitis is a distinct clinical hallmark of spondyloarthropathy in children and adults. Ultrasonography (US) is a powerful tool to detect enthesitis. There are only a few studies on US detected enthesitis in Juvenile Idiopathic Arthritis - Enthesitis Related Arthritis (JIA-ERA) from India. <h3>Objectives</h3> To assess the presence of clinical and US detected enthesitis in JIA- ERA and to correlate with disease activity. <h3>Methods</h3> 51 consecutive JIA-ERA patients fulfilling the ILAR classification criteria were evaluated clinically and sonographically from October 2016 to September 2017 in a tertiary care centre from Northern India. Enthesitis was clinically assessed using the MASES (Maastricht Ankylosing Spondylitis Enthesitis Score). Additionally peripheral entheseal sites of lower limb (insertion of plantar fascia at calcaneal tuberosity, insertion of Achilles at superior pole of calcaneus, quadriceps tendon at superior pole of patella and patellar tendons proximally at inferior pole of patella and distally at anterior tibial tuberosity) were clinically and sonographically assessed for enthesitis. The clinical assessment included JADAS 27 and BASDAI for disease activity and BASFI for function. Ultrasound was performed with a multi-frequency linear-array transducer (8-13MHz) using B-mode settings of dynamic range (40-50dB); GS- frequency (11-13 MHz); GS gain (60 dB). Power Doppler (PD) mode settings used: pulsed repetition frequency (400-800 Hz); PD-gain (highest possible gain with minimum background noise). US parameters (hypo echogenicity, increased thickness of entheses, intratendinous calcification, enthesophyte and erosion(s)) were assessed according to OMERACT 2014 definitions of ultrasonography findings of enthesitis (1). Each parameter at every site was scored as 1 if present and 0 if absent. Grading of Power Doppler signals was done as per definition by Kiris et al (2); Grade 0-no signal, Grade 1- separate dot signals or short linear signals, Grade 2- vascularity involving less than half of the enthesis, Grade 3-vascularity involving more than half of the enthesis. US enthesitis score was calculated by adding 1 point for each positive finding and the grade of PD. PD score was calculated by adding the grade of PD. Presence of clinical and US detected enthesitis was correlated with parameters of disease activity by Spearman's correlation coefficient. <h3>Results</h3> The mean age of patients was 14.3± 3.2 years with mean duration of disease 34.6±4.9 months. Male: Female ratio was 7.5:1. Clinical enthesitis was seen in 36 of the 51 patients (70.5%) while US detected enthesitis in all (p&lt;0.0001). The mean JADAS score, BASDAI and BASFI were 17.1±10.2, 4.1 ±2.4and 37.2±27.2 respectively, indicating active disease. The US enthesitis score correlated positively with JADAS (r = 0.3, P=0.03), BASDAI (r = 0.39, P=0.005) and BASFI (r = 0.38, P=0.006). PD score correlated positively with BASFI (r= 0.33, P- 0.02), but did not correlate with JADAS (r = 0.22, P=0.1), BASDAI (r= 0.24, P= 0.08). <h3>Conclusion</h3> Ultrasound is more sensitive in detecting enthesitis in JIA-ERA than clinical assessment. The US enthesitis score correlated positively with disease activity which has implications for treatment. <h3>References</h3> [1] Terslev L, Naredo E, Iagnocco A, Balint PV, Wakefield RJ, Aegerter P, et al. Defining enthesitis in spondyloarthritis by ultrasound: results of a Delphi process and of a reliability reading exercise. Arthritis Care Res (Hoboken). May;66(5):741-8. [2] Kiris A, Kaya A, Ozgocmen S, Kocakoc E. Assessment of enthesitis in ankylosing spondylitis by power Doppler ultrasonography. Skeletal Radiol. 2006Jul;35(7):522-8. <h3>Disclosure of Interests</h3> None declared