The 493th case: recurrent edema of bilateral lower extremeties / 中华内科杂志

A 43-year-old male patient with onset of edema caused by nephrotic proteinuria and low titer of anti-M type phospholipase-A 2-receptor (PLA 2R) antibody was diagnosed as idiopathic membranous nephropathy by renal biopsy. Administrated with prednisone 40 mg once a day and cyclosporine 100 mg twice a day as front-line regimen, the patient relapsed after transient partial remission. When treatment was combined with cyclophosphamide 100 mg once a day, the 24-hour total urine protein and titer of anti-PLA 2R antibody were even elevated. Therefore, the patient received rituximab 1 g intravenously in April 2019, October 2019 and October 2020 respectively. CD19 positive B lymphocytes in peripheral blood were eliminated from 71/μl to zero. Immunosuppressants and corticosteroids were withdrawn successively. On the last follow-up in November 2020, the anti-PLA 2R antibody was negative, and the 24-hour total urine protein and serum albumin was 4.4 g and 34 g/L, respectively. This case suggested the potential efficacy of rituximab for refractory membranous nephropathy. Further studies should explore whether the titer of anti-PLA 2R antibody indicates the dose of rituximab.

Diagnostic value of renal phospholipase A2 receptor and serum anti-phospholipase A2 receptor antibody in membranous nephropathy / 中南大学学报(医学版)

Objective:To examine the expression ofphospholipase A2 receptor (PLA2R) in renal tissues and the level of anti-PLA2R antibody in serum in patients with idiopathic membranous nephropathy (IMN) and secondary membranous nephropathy (SMN),and to evaluate their diagnostic value in IMN.Methods:A total of 73 patients,who were diagnosed between May,2014 and February,2015 in the Department of Nephrology of the Second Xiangya Hospital,Central South University,were divided into three groups:an IMN group (n=48),an SMN group (n=17) and a minimal change disease group (n=8) according to the renal biopsy.PLA2R expression in renal tissues and the level of antiPLA2R antibody in serum were detected by indirect immunofluorescence technique.Results:The positive rate and fluorescence intensity for PLA2R in the renal tissues in the IMN group were higher than those in the SMN group (91.7％ in the IMN group vs 29.4％ in the SMN group,P＜0.05),while the positive rate and serum level for anti-PLA2R antibody in the IMN group were higher than those in the SMN group (85.4％ in the IMN group vs 29.4％ in the SMN group,P＜0.05);the expression of PLA2R in renal tissues and the serum level for anti-PLA2R antibody were not detected in the minimal change disease group,The serum level of anti-PLA2R antibody was positively correlated with 24 h urine protein (r=0.432,P＜0.01) and negatively correlated with serum albumin (r=-0.307,P＜0.05).Conclusion:The expression of PLA2R in renal tissues and the serum level of anti-PLA2R antibody might be potential markers for diagnosis oflMN.

Research Progress of PLA2R and anti-PLA2R Antibodies in Membranous Nephropathy / 现代检验医学杂志

In recent years,the phospholipase A2 receptor in membranous nephropathy as an antigen has been confirmed,people have a new understanding of the mechanism of membranous nephropathy.Abundant clinical trials showed anti-PLA2R antibody in membranous nephropathy formed the important pathogenic mechanism,and it's related to disease activity,result and prognosis,it can also predict the process of disease remission,even can help make treatments for patients.This paper gathered some progress locally and abroad to describe the anti-PLA2R antibody's in function membranous nephropathy.

Expression of Serum Anti PLA2 R Antibodies in Idiopathic Membranous Nephropathy / 现代检验医学杂志

Objective To analyze the expression of serum anti M phospholipase A2 receptor (PLA2R)antibody in idiopathic membranous nephropathy (IMN),and to investigate its value in the diagnosis and evaluation of idiopathic membranous ne-phropathy.Methods One hundred and eighteen patients with biopsy-proved glomerular diseases were involved in this study, including 97 cases with IMN,21 cases with IgA nephropathy (IgAN)and 19 healthy people.ELISA was used to detect ser-um anti-PLA2R antibodies.Correlations of anti-PLA2R antibody level with laboratory parameters,including serum albumin, 24-hour urine protein of IMN patients were evaluated.Results The median of anti PLA2R antibody in IMN group,IgAN group and healthy group was 45.2(3.6~705.9)RU/ml,5.9(2.3~10.6)RU/ml and 1.2(0.6~9.3)RU/ml.The levels of serum anti PLA2R antibody in IMN group were higher than those in IgA nephropathy group and healthy control group.The difference was statistically significant (t=-5.027,-3.077;P=0.05).Among 97 cases with IMN,76 cases showed posi-tive anti-PLA2R antibodies (positive rate 78.35%).There was none patient showed positive anti-PLA2R antibody respec-tively in IgAN and healthy people.Furthermore,anti-PLA2R antibody level was negatively correlated with serum albumin (r=-0.453,P=0.000)and positively correlated with CREA,TC,ESR,24 hour urine protein (r=0.233,0.234,0.363, 0.586;P=0.004,0.217,0.021,0.000)in IMN patients.Conclusion Serum anti PLA2R antibody may be used as a IMN specific marker for the diagnosis of IMN,and it has important reference value for evaluating the severity of IMN.

The clinical value of plasma M type phospholipase A2 receptor antibody and IgG subtypes deposition in diagnosis of hepatitis B virus-associated membranous nephropathy / 国际检验医学杂志

Objective To investigate the different expressions of plasma M type phospholipase A2 receptor antibody and IgG subtypes deposition of kidney tissues in idiopathic membranous nephropathy and hepatitis B virus-associated membranous nephropa-thy,and to evaluate the significance of plasma M type phospholipase A2 receptor antibody and IgG subtypes in diagnosis of hepatitis B virus-associated membranous nephropathy.Methods Plasma samples were obtained from patients with idiopathic membranous nephropathy,hepatitis B virus-associated membranous nephropathy and minimal change disease,respectively,before immunosup-pressive therapy.Concentration of plasma M type phospholipase A2 receptor antibody was detected by sandwich ELISA and concen-tration of IgG subtypes were measured by immunofluorescence.Results Concentration of plasma M type phospholipase A2 receptor antibody was (15.4±7.2)μg/mL in idiopathic membranous nephropathy group,higher than that in the hepatitis B virus-associated membranous nephropathy group (10.3±5.7)μg/mL (P <0.01),between idiopathic membranous nephropathy group and hepatitis B virus-associated membranous nephropathy group.There was no distinct difference of IgG subtypes deposition in glomerlar capil-lary wall.Conclusion There is obvious clinical significance of concentration of plasma M type phospholipase A2 receptor antibody in differential diagnosis of idiopathic membranous nephropathy and hepatitis B virus-associated membranous nephropathy,while no distinct significance of IgG subtypes deposition.