August 31, 2017
Autoantibody formation directed against PLA2R1 is the underlying etiology in most cases of primary membranous glomerulopathy. This new understanding of the pathogenesis of primary membranous has rapidly transformed diagnosis and monitoring of this disease. Proteinuria can take months to resolve after a patient has undergone serologic remission and, as a result, is not an ideal biomarker of disease activity. Testing for levels of serum PLA2R autoantibodies gives a more accurate picture of the patient’s current disease status. Ideally, serum PLA2R testing would be performed immediately after biopsy diagnosis in cases with positive PLA2R staining on biopsy. At this point in time, negative serum testing in a patient known to have PLA2R-positive membranous indicates that the patient has undergone serologic remission and will likely not require immunosuppression to achieve remission of proteinuria. Repeat testing to monitor disease activity during and after treatment has also been recently recommended (see reference below).
Reference: J Am Soc Nephrol. 2017 Feb;28(2):421-430.