CLINICAL AND SEROLOGICAL CHARACTERISTICS AND RENAL OUTCOMES ACROSS HISTOLOGICAL CLASSES OF LUPUS NEPHRITIS: A RETROSPECTIVE COHORT STUDY

Reyhan KÖSE ÇOBANOĞLU, Utku ŞENTOSUN, Hasan BAYINDIR, Gökhan SARGIN

Journal of Experimental and Clinical Medicine - 2026;43(2):183-190

Department of Internal Medicine, Divison of Rheumatology, Faculty of Medicine, Aydın Adnan Menderes University, Aydın, Türkiye

 

Lupus nephritis (LN) is classified histopathologically according to the 2003 International Society of Nephrology/Renal Pathology Society (ISN/RPS) classification. We aimed to compare characteristics and renal outcomes across histological classes of LN, with particular emphasis on class I/II disease. We conducted a retrospective cohort study of patients with biopsy-proven LN. Patients were categorized into three groups: class I/II, class V or mixed class II/V, and proliferative class III/IV(+/-V). Baseline demographic, clinical, and serological characteristics and short-term renal outcomes [12-month complete renal response (CRR), partial renal response (PRR), and inadequate renal response (IRR)] were compared between groups. Long-term outcomes [chronic kidney disease (CKD) or end-stage renal disease (ESRD)] were assessed with survival analyses. A total of 82 patients were included: 13 with class I/II, 15 with class V or mixed class II/V, and 54 with proliferative class III/IV(+/-V) LN. Baseline proteinuria and serum creatinine levels were significantly higher, whereas the estimated glomerular filtration rate (eGFR) was significantly lower, in patients with proliferative disease (all p<0.05). Most demographic, clinical, and serological features were otherwise comparable, except for anti-centromere B positivity, observed only in the class I/II group (27%, p=0.004). Rates of renal responses at 12 months were similar across groups (p=0.766). During a mean follow-up of 158 months, 18 patients (22%) developed CKD or ESRD. Ten-year CKD/ESRD-free survival was 82% in both class I/II and in class V or II/V and was 77% in class III/IV(+/-V) LN, respectively, without significant differences between groups (log-rank p=0.371). Patients achieving CRR or PRR showed a trend toward better renal survival compared with non-responders (log-rank p=0.065). These findings underscore the clinical heterogeneity across LN classes and the need for individualized management beyond histopathology, while the long-term prognosis of class I/II LN remains to be clarified in prospective studies.