Comparison of phospholipase A2 receptor antibody serum levels in patients with primary and secondary membranous nephropathy and evaluate its association with proteinuria in this disease

Abstract

The use of anti-phospholipase A2 antibody (PLA2R) as a diagnostic biomarker in membranous nephropathy and the differentiation of primary cases from secondary cases has become important issue for researchers. Considering the different prevalence of this antibody in many published papers, the aim of this study is to investigate the level of anti-PLA2R antibody in primary and secondary types of membranous nephropathy as a diagnostic biomarker, an alternative to kidney biopsy and to evaluate its relationship with the level of proteinuria, creatinine clearance and the urine volume. Materials and Methods: this is a cross-sectional study. 35 adult patients referred to Imam Reza Hospital in Tabriz and Sheikh Al Rais Outpatient Clinic in the period from April 1401 to April 1402 (for 13 months) who their diagnosis was confirmed by kidney biopsy entered to the study. Using a checklist, patient demographic information, last creatinine and information related to the last 24-hour urine test were recorded. After complete collection of samples, serological test was performed and serum level of anti-PLA2R antibody was compared in two groups of patients with primary or idiopathic membranous nephropathy (iMN) and secondary and also the relationship between the serum level of the antibody and the level of proteinuria was investigated and evaluated in terms of the severity of the disease. Results: The mean age of the patients was 47.7 years. 18 people (51.4%) were women. The average antibody level in iMN patients was significantly higher than sMN group. (235.49 ± 309.26 and 6.23 ± 10.10 and p<0.03). The mean 24-hour urine proteinuria was higher in iMN patients than sMN group, although this difference was not statistically significant (2468.97 ± 4310.33 and 2864.15 ± 3715.5, respectively, p = 0.366) and Also, the level of anti-PLA2R antibody was positive in 18 patients with iMN, while it was not positive in any of the secondary cases. No statistically significant correlation was found between anti-PLA2R antibody serum levels and 24-hour urine proteinuria, 24-hour serum and urine creatinine, and urine volume.