Background Juvenile systemic lupus erythematosus (jSLE) is rare but associated with a worse prognosis than adult-onset disease. This has been attributed to higher risk of renal involvement, a tendency to have more active disease over time, receive more intensive immunosuppressive treatment and accrue more damage over a longer duration of disease.

Objectives To describe the pattern of disease expression with special focus on renal outcomes in a cohort of patients with jSLE in a tertiary hospital.

Methods Retrospective analysis of medical records in a group of jSLE patients. Statistical analysis was done using Excel 14.4.5 and SPSS 20.0.

Results 25 patients were included, with disease onset between 6 and 17 years of age (mean 12.5), and mean disease duration of 7.8 years (1-28). 23 (92%) patients were females. Current mean age is 20.4±5.9 years (13–37).

The most common disease manifestations were mucocutaneous (84%), musculoskeletal (68%) and hematological abnormalities (68%).

Lupus nephritis was diagnosed in 11 (44%) patients, all confirmed with renal biopsy. 9 patients had class IV (2003 ISN/RPS), 1 class V and 1 class V + II nephritis. According to the EULAR/ERA-EDTA 2012 renal response criteria, after 6 months, 7 (64%) had complete response to treatment, 1 (9%) partial response and 3 (27%) remained active. After 12 months, 8 (73%) had complete response and 3 (27%) remained active. The 3 patients with renal refractory disease at 6 months were diagnosed before 2003, had class IV nephritis and received monthly IV cyclophosphamide (CY) and pulse methylprednisolone (MP). 3 patients (2 class IV and 1 class II+V nephritis) received mycophenolate mofetil (MMF), plus steroids, as induction and maintenance therapy and all achieved complete remission, with an average follow-up of 1.3 years. During follow-up of the 6 and/or 12-month responsive patients, 1 flared after 15 months, 1 after 10 years and 1 after 6 years (all class IV nephritis), which were treated with add-on rituximab (after failing CY and/or MMF); 2 had complete remission after 6 months and 1 had partial remission.

All patients with lupus nephritis received corticosteroids, 8 (72%) pulse IV MP, 10 (90%) MMF, 8 (72%) IV CY, 7 (64%) azathioprine, 6 (54%) hydroxychloroquine and 9 (82%) angiotensin-converting enzyme inhibitors.

Only 1 patient has chronic kidney disease (Stage II - Glomerular Filtration Rate 76 mL/min/1.73m²) who is currently 37 years old, never achieved complete renal remission and is morbidly obese.

Conclusions Our results are in agreement with the literature, with a high incidence of lupus nephritis in juvenile-onset patients. Despite a limited follow-up, induction treatment followed by maintenance with MMF in our cohort achieved 100% complete response rates. Rituximab was effective as rescue add-on therapy in refractory disease. Renal and vital outcomes were good, with no patients with end-stage renal disease or deaths.

However, we need long-term follow-up to properly evaluate how the degree of renal involvement affects the mortality and morbidity of patients in the cohort and how newer treatment options will fare in the years to come.

Disclosure of Interest None declared