Preference for anti-phospholipase A2 receptor antibody assay in patients with suspected membranous nephropathy: a survey study on medical practice after publication of Japanese Guidelines for Nephrotic Syndrome 2020.

ABSTRACT

BACKGROUND: International practice guidelines advocate for the use of anti-phospholipase A2 receptor (PLA2R) antibody testing to diagnose primary membranous nephropathy (pMN). This study aimed to clarify the current status of anti-PLA2R antibody testing in the diagnosis of pMN in Japan and to scrutinize the factors associated with the implementation of this antibody test. METHODS: Utilizing a web-based questionnaire for nephrologists, responses were collected from 306 facilities and 427 nephrologists between November 2021 and December 2021. Preference for anti-PLA2R antibody testing was also investigated. Factors related to the experience of quantifying anti-PLA2R antibodies were estimated by generalized estimating equations using a robust analysis of variance with clusters of facilities of affiliation. RESULTS: Of the 427 respondents, 140 (32.8%) had previous measurement experience at their current workplace and 165 (38.6%) had previous measurement experience overall. In pMN-suspected cases without contraindications to renal biopsy, 147 (34.4%) of the respondents opted to request anti-PLA2R antibody testing. The respondents' experience with anti-PLA2R antibody quantification at their current place of work was generally higher in university hospitals and increased with the annual number of kidney biopsies and the number of years since graduation. CONCLUSION: The results of this study suggest that a significant proportion of nephrologists in Japan have no experience in performing anti-PLA2R antibody assays, and that the assays may be hampered by the limited capabilities of the current workplace and the financial burden on facilities and patients.