Interleukin-34 and Disease Activity in Systemic Lupus Erythematosus Patients

Abstract

Systemic Lupus Erythematosus (SLE) is characterized by exacerbation and remission, which needs close monitoring of the disease activity. Systemic lupus erythematosus disease activity can be determined by the SLE Disease Activity Index (SLEDAI) score. Evaluation of the disease activity is essential to be a guidance for treatment. Interleukin-34 (IL-34) is related to the pathogenesis of SLE. Serum IL-34 can be a candidate marker to evaluate SLE disease activity, and it is correlated with the SLEDAI score. This study aimed to determine the correlation between IL-34 level and disease activity in SLE patients based on the SLEDAI (Mex-SLEDAI) score. An observational analytical study with a cross-sectional design was carried out in six months (June-November 2019) in 27 SLE patients in the Department of Internal Medicine, Faculty of Medicine, Sumatera Utara University/Adam Malik General Hospital, Medan. Systemic lupus erythematosus disease activity was measured based on the Mex-SLEDAI score. Serum and urine were collected to obtain the Mex-SLEDAI score and IL-34 level. IL-34 level was measured in all subjects by using Enzyme-Linked Immunosorbent Assay (ELISA). Spearman correlation test was used to determine the correlation between IL-34 level and disease activity in SLE patients based on the SLEDAI (Mex-SLEDAI) score. There was a significant correlation between IL-34 level and disease activity in SLE patients based on SLEDAI (Mex-SLEDAI) score (r=0.965, p < 0.001). Further studies were needed with a sample of SLE patients in a balanced proportion based on their disease activity to obtain representative IL-34 levels in SLE patients based on their disease activity.