The investigative burden of membranous nephropathy in the UK

Abstract

Abstract Background Membranous nephropathy (MN) represents two distinct disease entities. Primary MN is now recognized as an autoimmune condition associated with the anti-PLA2R antibody and secondary MN occurs in tandem with malignancy, infection, drug therapy and other autoimmune conditions. Prior to the development of accessible enzyme-linked immunosorbent assays, the diagnosis of MN was one of exclusion. We studied whether the introduction of serum anti-PLA2R antibody testing leads to a reduction in the frequency of investigations in MN patients. Methods Patients from three UK centres with a diagnosis of MN between 2009 and 2014 were identified. We compared patients who had a positive anti-PLA2R test within 6 months of biopsy with those who had no test or a negative test. Records were reviewed for investigations that took place 6 months prior to and 6 months following the biopsy date to see if these were normal or identified a secondary cause of MN. Results In total, 184 patients were included: 80 had no test, 66 had a negative anti-PLA2R test and 38 had a positive test within 6 months of diagnosis. In 2012, 46.5% of patients had an anti-PLA2R test, increasing to 93.3% in 2014. From 2012 to 2014 the number of screening tests dropped from 10.03 to 4.29 and the costs from £497.92 to £132.94. Conclusions Since its introduction, a progressively higher proportion of patients diagnosed with MN had an anti-PLA2R test. This has led to a reduction in the number of screening tests and in the cost of investigations carried out. The anti-PLA2R test has the potential to reduce this burden as its use becomes more widespread.