CHILDHOOD-ONSET SYSTEMIC LUPUS ERYTHEMATOSUS OVER THE LAST 25 YEARS: PREDICTING ORGAN DAMAGE

Sa？etak Background: Childhood-onset systemic lupus erythematosus (cSLE) is a chronic autoimmune disease with the course often more severe than in adults, and the activity of the disease widely being evaluated by SLE Disease Activity Index (SLEDAI 2K) and damage by the SLICC/ACR damage index (SDI). Objectives: To explore the correlation between the SLEDAI-2K disease activity index at the time of diagnosis and the SLICC/ACR damage index of patients at their last follow up and to predict the risk of organ damage occurrence in time. Methods: The retrospective study included children treated for cSLE from January 1991 to September 2017 at Department of Pediatrics, UHC Zagreb. All children were diagnosed according to the ACR 1997 and SLICC 2012 criteria. Results: The disease development of 93 children (74 females) with cSLE was examined in this study. The median (range) follow up time was 7 (0.5–24) years and the median (range) age at diagnosis was 13 (5–19) years. Mean (SD) SLEDAI-2K was 18.3 (9.0) at the disease onset. 35 children (38 %) had organ damage at the last follow up with the median (range) SDI 0 (0–7). Th e first organ systems damaged in affected patients were renal (28%), musculoskeletal (22%), ocular (19%), neuropsychiatric (17%), cardiovascular (11%) and peripheral vascular (2.8%). A statistically signifi cant positive correlation was found between SLEDAI-2K at the disease onset and SDI (τb = 0.252, p = 0.003). No significant correlation was determined between the duration of the disease (τb = 0.042, p = 0.628) or follow up period (τb = 0.111, p = 0.191) and SDI, nor in SDI in regard to gender (p= 0.574). Using Kaplan-Meier method we estimated the decrease in ratio of patients without organ damage since diagnosis or the occurrence of the first symptoms. Since the estimated ratio of patients with organ damage at the endpoint was less than 50%, we could not estimate the time required for damage development in 50% of patients. However, we are 95% sure that the damage is not happening in the first 9 years aft er diagnosis. Conclusions: The high correlation detected between SLEDAI-2K and SDI indicated that the presentation of the cSLE at onset can be prognostic of the course and long-term prognosis of lupus. Our findings suggest that it is unlikely that organ damage will occur in 50% of patients in the first nine years of the disease course. References: 1. Gladman DD, Ibanez D, Urowitz MB. Systemic lupus erythematosus disease activity index 2000. J Rheumatol. 2002; 29:288–91