Juvenile-onset SLE; disease activity, severity and damage - the UK JSLE Cohort Study

<b>Objective</b> The UK JSLE Cohort Study is a multi-centre collaborative network established with the aim of improving the understanding of JSLE. The primary aim of this study is to describe the clinical manifestations and disease course of a large, national inception cohort of patients with JSLE.<p></p> <b>Methods</b> Detailed phenotypic data was collected at baseline, with regular clinical reviews and annually in 232 patients, from 14 centres across the UK over 4.5 years. Patients were identified according to their American College of Rheumatology (ACR) SLE classification criteria: “JSLE” patients (n=198) fulfilled ≥4 ACR criteria and were included in this study.<p></p> <b>Results</b> For JSLE patients, sex distribution was 5.6:1 (female:male) with a median (IQR) age of 12.6 (10.4-14.5) years at diagnosis. Male patients were younger (p<0.01). Standardised ethnicity data demonstrated greater risk of JSLE in non-Caucasian UK patients (p<0.05). A paediatric adaptation of BILAG2004 demonstrated significant musculoskeletal (82%), renal (80%), haematological (91%), immunological (54%), and neurological (26%) involvement over time. The cohort had a high steroid burden (93%) and 24% required cyclophosphamide. Disease damage was common with 28% having ≥1 Systemic Lupus International Collaboration Clinic (SLICC) score.<p></p> <b>Conclusion</b> The UK JSLE Cohort Study, one of the largest national JSLE inception cohorts to date, has demonstrated severe organ involvement and significant disease activity. Damage accumulation is also seen