Correlation Between Quantitative Anti-dsDNA Levels with Severity of Proteinuria in Systemic Lupus Erythematosus Patients

Abstract

Objective: To evaluate the correlation of quantitative anti-dsDNA level with proteinuria levels in patients with lupus nephritis in a tertiary care hospital.

Study design: In this prospective cross-sectional study, 76 patients of newly diagnosed SLE coming to Fatima Memorial Hospital were included in the study period between January 2020 to June 2020. Demographic data such as age, gender, lupus manifestations such as serositis, arthritis, mucocutaneous disease, and neuropsychiatric manifestations were recorded. Quantitative anti-dsDNA was measured by enzyme-linked immunosorbent assay and proteinuria was estimated by 24h urinary protein collection. Data was analyzed by SPSS 23. Association between categorical variables was assessed using chi-square test. For comparison of categorical independent and continuous dependent variable t-test or Mann-Whitney U test was applied.

Results: The median age of the cohort was 29 (with inter quartile range - IQR - of 13) years. The female gender comprised of 68 (89.4%) of the cohort population. The median anti-dsDNA level was 54.9 (183.6 IQR) IU, and baseline proteinuria of the cohort was 520mg/dL (1.49 IQR). There was a significant association of anti-dsDNA level with systemic features such as arthritis (p=<0.01), serositis (p=<0.01) and, Raynaud's phenomenon (p=<0.01). NPSLE and mucocutaneous features did not show statistically significant association (p=0.91 and 0.14 respectively). Baseline anti-dsDNA showed a statistically significant correlation with baseline proteinuria levels (p=<0.01).

Conclusion: Quantitative anti-dsDNA is directly correlated with nephritis measured as proteinuria, and can be detected even before organ involvement. Hence, it can determine disease course and guide early treatment.

Keywords: Anti-dsDNA; Lupus eritematoso sistémico; Nefritis; Nephritis; Systemic lupus erythematosus.