THU0274 RENAL CHARACTERISTICS AND OUTCOME OF LUPUS NEPHRITIS ACCORDING TO ITS TIME OF ONSET

Abstract

Background:Lupus nephritis (LN) usually develops within 5 years of systemic lupus erythematosus (SLE) onset. It is unclear whether the course and outcome of LN differ between patients who initially had LN at SLE onset (initial-onset LN) and those who developed LN within 5 years after SLE onset (early-onset LN).Objectives:To compare clinical characteristics and renal outcomes between SLE patients with initial-onset LN and SLE patients with early-onset LN.Methods:SLE patients with biopsy-proven LN were retrospectively reviewed. The clinical parameters and renal outcomes were compared between initial-onset LN and early-onset LN groups. We used Cox regression analysis to estimate risk of worse renal outcome, according to the onset time of LN.Results:Of the total 136 LN patients, 92 (67.6%) and 44 (32.4%) patients were classified into the initial-onset and early-onset LN groups, respectively. The initial-onset LN group had higher prevalences of impaired renal function (34.8% vs. 11.4%, p=0.004) and microscopic hematuria (73.9% vs. 54.5%, p=0.024), and higher urine protein/creatinine ratio (4626.1 [2180.0–6788.3] vs. 2410.0 [1265.0–5168.5] mg/g, p=0.006) at LN diagnosis. Renal relapse (46.3% vs 25.7%, p=0.039) and progression to chronic kidney disease (CKD) or end-stage renal disease (ESRD) were more common (24.4% vs. 8.3%, p=0.042) in the initial-onset LN group. In the multivariable Cox regression analysis, initial-onset LN group had higher risk of renal relapse (adjusted hazard ratio [HR] 2.938, 95% confidence interval [95% CI] 1.344–6.426, p=0.007) and progression to CKD or ESRD (adjusted HR 4.642, 95% CI 1.107–19.458, p=0.036), compared with early-onset LN group.Conclusion:Patients with LN at SLE onset may have more severe renal presentations and worse renal outcome than those who develop LN within 5 years.