AB0839 A STUDY OF SERUM COMPLEMENT AND SERUM CALPROTECTIN LEVEL IN SYSTEMIC LUPUS ERYTHEMATOSUS

Abstract

Background:Serum calprotectin, also known as MRP8/14 or S100A8/A9, has gained attention in recent years as a candidate biomarker in inflammatory diseases like SLE.1 Proteins of the complement pathway (serum C3 and C4) are linked to the pathogenesis of SLE and their levels have been measured as a means to assess the disease activity.2Objectives:[1]To study the relation of serum complement and serum calprotectin levels to disease activity in SLE[2]To study the relation between serum complement and serum calprotectin level in SLEMethods:Our study was a hospital based observational study conducted in a tertiary care centre in North-East India during the period of June 2019 to May 2020. A total of 102 patients of SLE were taken up for the study. Disease activity was assessed using SLEDAI-2K scores and serum calprotectin level was measured by ELISA. Serum C3 level was assessed by Nephelometric and C4 level by Turbidimetric immunoassay. The statistical significance was fixed at 5% level of significance (p<0.05) for all analysis.Results:Our study found a predominantly female population (Female: Male ratio 24.5: 1) with majority of the patients (49.02%) in the 30-39 years age group. Higher calprotectin levels were seen in patients with higher disease activity (SLEDAI) and this relation was statistically significant (r=0.84, p<0.001). There was significant negative correlation between disease activity (SLEDAI) and serum C3 (r=-0.35, p<0.001) and serum C4 (r=-0.4, p<0.001) level. There was a significant negative correlation between complement levels and serum calprotectin levels (r=-0.53, p<0.001).Conclusion:We found a significant positive correlation between serum calprotectin level and disease activity with a significant negative correlation between complement level and disease activity in SLE patients. There was a significant negative correlation between serum complement and serum calprotectin levels. These findings suggest serum calprotectin levels could be a substantial addition in the existing diagnostic array of tools in assessing lupus disease activity.