Role of Serum and Urine Biomarkers (PLA(2)R and THSD7A) in Diagnosis, Monitoring and Prognostication of Primary Membranous Glomerulonephritis

Differentiating primary and secondary membranous glomerulonephritis (MGN) using biomarkers for MGN is essential in patients’ diagnosis, treatment and follow-up. Although biopsy has been the primary tool in making the diagnosis, not all patients can withstand it due to its invasive nature, and it cannot be used to monitor treatment. Hence, there is the need for less invasive or even non-invasive biomarkers for effective diagnosis, treatment monitoring and prognostication. This study aimed at providing an alternative way of differentiating primary and secondary MGN using enzyme-linked immunosorbent assay (ELISA) technique for serum and urine biomarkers (M-type phospholipase A2 receptor (PLA(2)R) and thrombospondin type-1 domain-containing 7A (THSD7A)) for prompt diagnosis, treatment and prognosis. A total of 125 subjects, including 81 primary and 44 secondary MGN subjects, were diagnosed from January 2012 to October 2019 at Hospital Serdang and Hospital Kuala Lumpur from which 69 subjects consisting of 47 primary and 22 secondary MGN subjects participated in the study. Of these, 13 primary MGN subjects were positive for both serum and urine anti-PLA(2)R antibodies (Ab) whereas only one secondary MGN subject associated with hepatitis B virus was positive for both serum and urine anti-PLA(2)R Ab. At the same time, anti-THSD7A Ab was found positive in four primary MGN subjects and two secondary MGN subjects with malignancy.