Lupus nephritis at systemic lupus erythematosus onset and kidney outcomes in a Latin American biopsy-proven cohort

Abstract

Background The prognostic relevance of lupus nephritis (LN) occurring at systemic lupus erythematosus (SLE) onset versus later remains uncertain, particularly in Hispanic populations. Methods We conducted a retrospective cohort study of adults (≥18 years) with biopsy-proven LN from tertiary centers in Colombia (2011–2024). The exposure was LN at SLE onset (LNSO), defined as LN diagnosed concurrently with SLE or with kidney biopsy within 30 days of SLE onset, versus LN occurring later (non-LNSO). The primary outcome was end-stage kidney disease (ESKD), defined as sustained eGFR <15 mL/min/1.73 m 2 for ≥3 months, chronic dialysis, or kidney transplantation. Secondary outcomes were all-cause mortality and a composite of ESKD, death, or doubling of creatinine. Associations were estimated using cause-specific Cox and Fine-Gray models. A 180-day landmark analysis assessed the impact of no remission at 6 months. Results Among 428 patients, 281 (65.7%) had LNSO and 147 (34.3%) non-LNSO. Median follow-up was 5.3 years. ESKD occurred in 72 patients (16.8%) and did not differ by LNSO status (log-rank p = 0.278). LNSO was not associated with ESKD (adjusted HR 0.87; 95% CI 0.48–1.60) or in competing-risk models (sHR 0.85; 95% CI 0.19–3.84). Lower baseline eGFR, higher NIH chronicity index, and higher non-renal damage were associated with ESKD. The composite outcome occurred in 156 patients and was not associated with LNSO. No remission at 6 months strongly predicted adverse outcomes. Conclusions LNSO was not independently associated with kidney or survival outcomes. Baseline function, chronicity, non-renal damage, and early response were the main prognostic factors.

The authors' abstract, as published at the source. Lupus, 2026 · DOI ↗