Disease activity, severity, and damage in the UK Juvenile-Onset Systemic Lupus Erythematosus Cohort.

Objective: The UK Juvenile-Onset Systemic Lupus Erythematosus (JSLE) Cohort Study is a multicenter collaborative network established with the aim of improving the understanding of juvenile SLE. The present study was undertaken to describe the clinical manifestations and disease course in patients with juvenile SLE from this large, national inception cohort.

Methods: Detailed data on clinical phenotype were collected at baseline and at regular clinic reviews and annual followup assessments in 232 patients from 14 centers across the UK over 4.5 years. Patients with SLE were identified according to the American College of Rheumatology (ACR) SLE classification criteria. The present cohort comprised children with juvenile SLE (n=198) whose diagnosis fulfilled ≥4 of the ACR criteria for SLE.

Results: Among patients with juvenile SLE, the female:male sex distribution was 5.6:1 and the median age at diagnosis was 12.6 years (interquartile range 10.4-14.5 years). Male patients were younger than female patients (P<0.01). Standardized ethnicity data demonstrated a greater risk of juvenile SLE in non-Caucasian UK patients (P<0.05). Scores on the pediatric adaptation of the 2004 British Isles Lupus Assessment Group disease activity index demonstrated significantly increased frequencies of musculoskeletal (82%), renal (80%), hematologic (91%), immunologic (54%), and neurologic (26%) involvement among the patients over time. A large proportion of the patients (93%) were taking steroids and 24% of the patients required treatment with cyclophosphamide. Disease damage was common, with 28% of the patients having a Systemic Lupus International Collaborating Clinics/ACR damage score of ≥1.

Conclusion: The data on these patients from the UK JSLE Cohort Study, comprising one of the largest national inception cohorts of patients with juvenile SLE to date, indicate that severe organ involvement and significant disease activity are primary characteristics in children with juvenile SLE. In addition, accumulation of disease-associated damage could be seen.