[Long-term outcome of paediatric lupus nephritis]

Kidney is frequently affected in patients with systemic lupus erythematosus (SLE). It has been recently suggested that the renal outcome in this disease has improved with an earlier diagnosis and intensive specific treatment. Quite often, articles with paediatric patients lack a prolonged follow-up which could help to predict long term outcome.

This is a retrospective descriptive study based on the review of clinical records from patients with a diagnosis of lupus nephritis in a Paediatric Nephrology unit of a tertiary care centre, between 1987 and 2009. Patients were included with an age up to 18 at diagnosis. They were excluded if follow-up period was shorter than 3 months or if data lacked about it. It includes descriptive evolution of clinical parameters, kidney function, lupus activity as well as pathology and treatment. Several variables were tested for association with chronic kidney disease (CKD) in the last checkpoint.

Data were obtained from 16 patients, 3 men and 13 women. Age at the beginning of SLE was 10.6 + or - 2.9 years and 12.6 + or - 3.5 years at debut of lupus nephritis. Biopsy was obtained in 14 of them, in 11 cases (78.6 %), 3 or less months following diagnosis. In 9 cases (64.3 per cent), biopsy showed WHO class IV, 3 cases, class III and 2 cases, class II. In the last control (10.7 + or - 6.7 years of follow-up), 7/16 (43.8 %) had developed CKD: 5 cases with proteinuria (one in nephrotic range), one in stage 2 and one patient in haemodialysis after renal graft loss. Among those with a follow-up longer than 10 years, 4/9 (44.4 %) of them showed some sign of renal disease: 3/9 with proteinuria, and the one needing haemodialysis. Most of the patients (15/16) received treatment with intravenous cyclophosphamide boluses in a variable number after diagnosis. Only a more intense proteinuria at 3 months, 1 year and 3 years of evolution was related to CKD in the last visit.

We consider the long term evolution of our patients to have been very satisfactory. Although 44.4 % of them developed renal anomalies after 10 or more years, only one (11.1%) reached an end-stage renal disease. These patients presented a higher grade of proteinuria from the first visits.