Background: A precise description of renal histological lesions and an appropriate classification of lupus nephritis are both essential for nephrologists to guide treatment and predict prognosis among patients. The prognostic value of ISN/RPS 2003 classification is controversial. A new classification for lupus nephritis was recently proposed, namely, the revised ISN/RPS 2018 classification.
Objective: The study aimed to evaluate the predictive value of the clinical and pathological factors according to ISN/RPS 2018 classification on renal remission among patients with proliferative lupus nephritis.
Methods: A total number of 41 patients with proliferative lupus nephritis on adequate renal biopsy specimen between 2017 and 2018 were included. Clinical and histological variables were tested for their association with renal remission. Univariate and multivariate logistic regression analysis were performed to identify independent predictors of renal remission after 24 weeks of induction therapy.
Results: After induction therapy, 56.1% of patients reached complete and partial remission and 43.9% reached no remission. In univariate analyses, baseline glomerular filtration rate (GFR), presence of anti-DNA titer, cellular crescents, interstitial inflammation, glomerulosclerosis, interstitial fibrosis, tubular atrophy and total chronicity index strongly impacted renal response. After multivariate logistic regression analysis, we identified aging, presence of cellular crescents, and high total renal chronicity index as independent predictors of renal remission. Receiver operating characteristic (ROC) analysis revealed that baseline estimated GFR (AUC = 0.708; 95% CI 0.527-0.888), anti-DNA titer (AUC = 0.674; 95% CI 0.491-0.858), cellular crescent (AUC = 0.750; 95% CI 0.585-0.915) and renal chronicity index (AUC = 0.765; 95% CI 0.585-0.915) predicted renal remission. Combining all factors achieved a perfect score predicting renal response (AUC 0.924; 95% CI 0.840-1.000).
Conclusion: The study identified baseline GFR, anti-DNA titer, cellular crescent, and high chronicity index according to revised ISN/RPS 2018 classification as important predictors of renal response after induction therapy in proliferative lupus nephritis.
Keywords: Lupus classification; Lupus nephritis; Pathological classification; Renal remission.