Diagnostic value of PLA2R, THSD7A and IgG subtypes in idiopathic membranous nephropathy

Objective To investigate the expression of serum anti-phospholipase A2 receptor (PLA2R) antibody, glomerular PLA2R, type 1 platelet reactive protein 7A domain (THSD7A) and IgG subtype in patients with idiopathic membranous nephropathy (IMN) and their diagnostic value for IMN. Methods A total of 72 patients with IMN, diagnosed by renal biopsy in Department of Nephrology, Ya'an People's Hospital from January of 2016 to June of 2019, were selected, and another 72 patients with non-IMN glomerular diseases in the same period were taken as the control group. Quantitative enzyme-linked immunosorbent assay (ELISA) was used to detect anti-PLA2R antibody titer. Immunofluorescence test (IFT) was used to detect the expression of glomerular PLA2R, THSD7A and IgG subtype. Receiver operator characteristic curves (ROC) were used to evaluate the diagnostic efficiency of serum anti-PLA2R antibodies, glomerular PLA2R, THSD7A and IgG4. Results The sensitivity of IMN diagnosis with serum anti-PLA2R antibody, glomerular PLA2R, IgG4 and THSD7A was 61.11%, 80.56%, 97.22% and 8.33%, respectively, and the specificity was 97.22%,100.00%,97.22% and 100.00%,respectively. If anyone of serum anti-PLA2R antibody and glomerular PLA2R was positive, the sensitivity of IMN diagnosis would be 83.33%. The sensitivity was 97.22% when IMN was diagnosed by any positive one of glomerular PLA2R, THSD7A and IgG4. Conclusions Serumanti-PLA2R antibody, glomerular PLA2R,THSD7A and IgG4 play an important role in the diagnosis and differential diagnosis of IMN. Detecting both PLA2R and its antibodies may increase the diagnostic accuracy of IMN. The combined detection of glomerular PLA2R, THSD7A and IgG4 can increase the sensitivity of IMN diagnosis.