FRI0176 NON-HISTOLOGIC FACTORS DISCRIMINATING PROLIFERATIVE LUPUS NEPHRITIS FROM MEMBRANOUS LUPUS NEPHRITIS
Authors: O. C. Kwon, J. H. Park, M. C. Park
Journal: Annals of the Rheumatic Diseases (2020)

Background: The treatment strategy and renal prognosis between proliferative lupus nephritis (LN) and membranous LN are different. Therefore, it is important to distinguish one from the other. To date, data regarding non-histologic factors that can discriminate proliferative LN from membranous LN are limited. Objectives: To investigate non-histologic factors that can discriminate proliferative LN from membranous LN in patients with systemic lupus erythematosus with renal manifestations. Methods: Patients with biopsy-proven proliferative LN and membranous LN were included. Non-histologic factors were compared between the two groups. A logistic regression analysis was performed to identify the factors associated with proliferative LN. To assess the accuracy of these factors in discriminating between proliferative LN and membranous LN, we performed a receiver-operating characteristic analysis. Results: Of the total 168 patients with biopsy-proven LN, 150 patients (89.3%) had proliferative LN, and 18 patients (10.7%) had membranous LN. In the multivariable logistic regression analysis, positive anti-double-stranded DNA (anti-dsDNA) antibody (adjusted OR = 11.200, 95% CI = 2.202–56.957, p = 0.004) was associated with proliferative LN, while positive anti-U1RNP antibody (adjusted OR = 0.176, 95% CI = 0.040–0.769, p = 0.021) and higher glomerular filtration rate (GFR) (adjusted OR = 0.973, 95% CI = 0.951–0.994, p = 0.013) were inversely associated with proliferative LN. Among these covariates, the anti-dsDNA antibody (area under the curve = 0.806, 95% CI = 0.695–0.916) had the highest accuracy in discriminating between proliferative LN and membranous LN. Conclusion: The positivity of anti-dsDNA antibody was associated with proliferative LN, while the positivity of anti-U1RNP antibody and GFR were inversely associated with proliferative LN. The anti-dsDNA antibody had a good accuracy in discriminating proliferative LN from membranous LN. References: Not applicable Table. Factors associated with proliferative LN Univariable analysis Multivariable analysis OR (95% CI) p OR (95% CI) p Age 0.982 (0.951–1.014) 0.269 Female sex 1.437 (0.295–7.006) 0.653 Positive anti-Sm Ab 0.648 (0.243–1.728) 0.386 Positive anti-Ro Ab 0.928 (0.341–2.529) 0.885 Positive anti-La Ab 2.075 (0.572–7.528) 0.267 Positive anti-U1RNP Ab a 0.271 (0.085–0.861) 0.027 0.176 (0.040–0.769) 0.021 Positive anti-dsDNA Ab a 7.333 (2.574–20.893) &lt;0.001 11.200 (2.202–56.957) 0.004 Low C3 a 9.970 (3.117–31.891) &lt;0.001 1.886 (0.255–13.932) 0.534 Low C4 a 3.839 (1.405–10.486) 0.009 1.224 (0.229–6.552) 0.813 GFR 0.980 (0.964–0.997) 0.021 0.973 (0.951–0.994) 0.013 Urine PCR 1.000 (0.987–1.013) 0.986 Urine RBC of ≥ 5/HPF 4.178 (1.516–11.509) 0.006 2.053 (0.426–9.893) 0.370 Urine WBC of ≥ 5/HPF 2.687 (0.958–7.543) 0.060 Urine cast 4.429 (0.567–34.578) 0.156 SLEDAI-2K 1.173 (1.063–1.294) 0.001 1.046 (0.900–1.216) 0.557 Variables with P value less than 0.05 in the univariable analysis were selected for inclusion in the multivariable analysis. a Analyzed as binary variables (Anti-U1RNP Ab, positive/negative; Anti-dsDNA Ab, positive/negative; C3, low/not low; C4, low/not low) Ab, antibody; anti-dsDNA, anti-double-stranded DNA; GFR, glomerular filtration rate; PCR, protein/creatinine ratio; RBC, red blood cell; HPF, high power field; WBC, white blood cell; SLEDAI-2K, Systemic Lupus Erythematosus Disease Activity Index 2000; OR, odds ratio; CI, confidence interval Acknowledgments: None. Disclosure of Interests: None declared