To investigate the clinical significance of M type phospholipase A2 receptor (PLA2R) antibody and thrombospondin type-1 domain-containing protein 7A (THSD7A) antibody in idiopathic membranous nephropathy (IMN) by detecting their titers in serum and urine of patients with IMN.

The patients who were diagnosed as MN by renal biopsy in the Department of Nephrology, Second Hospital of Shanxi Medical University from July 2015 to December 2017 were selected. The levels of PLA2R antibody and THSD7A antibody in serum and urine were determined by enzyme-linked immunosorbent assay (ELISA).

The 189 patients were diagnosed as MN by clinical and pathological methods, including 165 patients (87.3%) in the IMN group. The positive rates of PLA2R antibody in the serum and urine of IMN patients were 64.8% and 60.0%, respectively, while the positive rates of THSD7A antibody were 8.4% and 5.4%, respectively. The serum and urine PLA2R antibody concentrations of IMN patients were positively correlated with the 24 h urinary protein quantification (P<0.05), and negatively correlated with serum albumin(P<0.05). In the IMN patients, the serum and urine THSD7A antibody concentrations were positively correlated with the 24 h urine protein quantification(P<0.05), but not with serum albumin(P>0.05). The PLA2R antibody concentration in the serum was positively correlated with that in the urine of the IMN patients(P<0.05), while the THSD7A antibody concentration in the serum was positively correlated with that in the urine of the IMN patients(P<0.05).

Both PLA2R antibody and THSD7A antibody in the serum and urine were shown to be potential specific markers for the diagnosis of IMN. Compared with the THSD7A antibody, the PLA2R antibody detection rate was higher, and the concentrations of these two antibodies in the serum and urine had a certain correlation with the clinical indicators.