#3-84E. The Hidden Risks: Low-Grade Proteinuria in Lupus Nephritis (Arthritis Rheumatol, 2026)

When managing lupus nephritis (LN), can we safely assume that low-grade proteinuria indicates a milder disease course and a favorable prognosis? This episode dives into a longitudinal cohort study of 239 biopsy-proven LN patients, stratifying them by baseline proteinuria levels and disease onset to evaluate renal pathology and long-term outcomes. Surprisingly, the study reveals that patients with low-grade proteinuria (less than 1 g/day) experience similar risks of renal function decline and comparable treatment responses as those with high-grade proteinuria. The core finding emphasizes that baseline low-grade proteinuria does not guarantee better renal outcomes, and glomerulosclerosis serves as a critical independent predictor of renal deterioration, particularly in relapsing LN. Critically evaluating this paper, it is important to note its retrospective design, the relatively small sample size of the low-proteinuria cohort, and the heterogeneity in individualized treatment regimens4. For clinicians, these findings are highly relevant; they underscore that mild proteinuria should not deter early renal biopsy or vigilant monitoring. Relying solely on proteinuria levels is insufficient, and early histologic evaluation remains essential to guide personalized immunosuppressive therapy and prevent irreversible chronic kidney damage.

Citation: Shen Y, Peng J, Dai D, et al. Low-Grade Proteinuria Does Not Predict Favorable Outcomes in Lupus Nephritis: A Longitudinal Cohort Study. Arthritis & Rheumatology. 2026. DOI: 10.1002/art.70009

Disclaimer: This audio summary is based on personal interpretation and does not guarantee the exact content of the original paper. Please refer to the original article for details.