Myeloperoxidase mRNA Expression in Neutrophils of Polyarticular and Enthesitis-related Juvenile Idiopathic Arthritis

Abstract

Background: Juvenile idiopathic arthritis (JIA) is the most common chronic rheumatic condition in childhood. Methods: This comparative cross-sectional study was conducted at the Genomic Research Laboratory, Department of Anatomy, Bangabandhu Sheikh Mujib Medical University (BSMMU) among polyarticular, enthesitis-related arthritis (ERA), and healthy children. Diagnosed patients of polyarticular JIA (15), enthesitis-related JIA children (15) and healthy children as control (15) who came for screening of arthritis directly or reffered by physicians at Department of Pediatric Rheumatology and General Pediatrics Outpatient Departments aged less than 16 years were included by conveniently by purposive sampling technique. RNA was isolated from the peripheral blood before synthesizing cDNA. The MPO mRNA expression was observed with a gene specific primer in real-time quantitative PCR. The gene expression was leveled as 2^-∆ct relative as compared to reference gene. Chi-square test and Fisher’s exact test was used for the level of significance. Clinical characteristics were described using SPSS version 24. Results: The mean age of the 45 participants with SD was 10.02±2.84 years. Then average age of onset of poly articular JIA in children was 10.5±3.1 years with male-to-female ratio was 2.78:1 in both diseased groups. In ERA group, the mean age at onset was 11.13 years and the lowest age was 8.5 years and the highest age was 14 years. A total of 13.3% of ERA children had a positive family history and only one child (6.7%) in the poly JIA group. The MPO mRNA expression was found significantly elevated (p <0.001). Conclusion: The gene expression status of MPO may be used in future to identify early changes in neutrophil activation.