Clinicopathological And Efficacy Analysis Of Atypical Membranous Nephropathy With PLA2R-Positive Antibodies

Atypical membranous nephropathy(AMN)is a pathological type of membranous nephropathy that is pathologically similar to secondary membranous nephropathy(SMN)in presentation,but no clear clinical cause has been found.In recent years,the incidence of AMN has increased year by year,and the rate of PLA2R antibody positivity is also close to that of IMN.However,there are few studies on PLA2R antibody-positive AMN at home and abroad,and this study will aim to enhance the understanding of PLA2R antibody-positive AMN by comparing the clinicopathological characteristics of PLA2R antibody-positive AMN with those of IMN.In addition,this study further investigates the relationship between PLA2R antibodies and the severity of AMN as well as the role of PLA2R antibodies in predicting the outcome of AMN.Objective:To investigate the clinicopathological characteristics of PLA2R-positive atypical membranous nephropathy and the role of serum PLA2R antibody titres in predicting the outcome of patients with atypical membranous nephropathy.Methods:This study is a single-center retrospective study.We selected atypical membranous nephropathy and idiopathic membranous nephropathy patients with complete clinical data and initial diagnosis and treatment of PLA2R antibody-positive patients who were hospitalized in the Department of Nephrology of Cangzhou People’s Hospital and underwent renal puncture biopsy from December 2020 to March 2022 as study subjects,collected general data,laboratory test indexes,and pathological data of the two groups,and compared the clinical and pathological differences between the two groups.The AMNgroup was divided into low titer and high titer groups according to PLA2R antibody titer.The treatment regimen and biochemical indexes of the two groups were followed up for 1 year,and the remission rates of the two groups were compared.Results:1.In terms of general conditions,there were no statistically significant differences between the two groups in terms of gender,mean age at onset,smoking history and clinical manifestations.2.In terms of laboratory parameters,triglycerides and D-dimer were higher in the AMN group than in the IMN group,and the differences were statistically significant.The differences in hemoglobin,blood albumin,24 h urine protein quantification,PLA2R antibody titer,urea nitrogen,blood creatinine,C3,C4,IgA,IgM,and IgG were not statistically significant between the two groups.3.In terms of renal pathology,under light microscopy,the proportions of glomerulosclerosis,tubular atrophy,interstitial inflammatory changes,interstitial fibrosis,and small arterial lesions in the AMN group were not statistically different from those in the IMN group.Under fluorescence,the rate and intensity of IgA,IgM,C1q and FRA positivity were higher in the AMN group than in the IMN group,and the difference was statistically significant.4.Serum PLA2R antibody titers in the AMN group were negatively correlated with blood albumin and positively correlated with urine protein quantification.5.The remission rate of the low-titer group in AMNwas higher than that of the high-titer group.Conclusions:PLA2R antibody-positive AMN may be a specific pathological manifestation of IMN rather than a separate pathological type,but it has its own characteristics with a little more severe clinical and pathological manifestations of immune disturbance.PLA2R antibody titres correlate with disease activity in AMN and are somewhat predictive of AMN remission rates.