Giant retinal pigment epithelium tears with membranous nephropathy: a case report and literature review.

BACKGROUND: Kidney and eye diseases may be closely linked. Tears of the retinal pigment epithelium (RPE) have been reported to be related to kidney diseases, such as IgA nephropathy and light-chain deposition disease. However, pigment epithelium tears associated with membranous nephropathy have not been reported or systematically analysed. CASE PRESENTATION: A 68-year-old man presented with decreased right eye visual acuity. Optical coherence tomography (OCT) revealed cystic macular edema, localized serous detachment of the retina and loss of the outer retinal structure in the right eye and retinal pigment epithelium detachment (PED) combined with serous detachment of the retina in the left eye. Fundus fluorescein angiography (FFA) and indocyanine green angiography (ICGA) revealed giant RPE tears in the right eye and exudative age-related macular degeneration in the left eye. The patient also suffered from severe membranous nephropathy-autoimmune glomerulonephritis. Renal biopsy immunofluorescence revealed a roughly granular pattern, with immunoglobulin G (IgA), immunoglobulin G (IgG), IgM, complement C3(Components 3), λ light chain and κ light chain subepithelial staining. CONCLUSIONS: It is hypothesized that severe membranous nephropathy caused immune complex deposition on the surface of Bruch membrane, resulting in weakened adhesion between the RPE and Bruch membrane and impaired RPE pump function, combined with age-related macular degeneration, leading to giant RPE tears in the right eye. Close attention should be given to the ocular condition of patients with membranous nephropathy to facilitate timely treatment and avoid serious consequences.

Development of a nomogram for membranous nephropathy prediction in patients with primary Sjögren's syndrome: a 6-year retrospective study.

Objectives: Nephritis is a life-threatening complication of primary Sjögren's syndrome (pSS), with membranous nephropathy (MN) being prevalent. Renal biopsy is the gold standard for MN diagnosis, but it is invasive and cannot be repeatedly performed. This study aimed to develop a nomogram for the prediction of MN in patients with pSS. Methods: This retrospective study included patients with pSS admitted to the Rheumatology and Immunology Department of the First Affiliated Hospital of China Medical University between January 2015 and January 2021. A nomogram was developed using multivariable logistic regression analysis and evaluated using receiver operating characteristic (ROC) curve analysis. Bootstrap resampling analysis (1,000 times) was performed to evaluate the nomogram for discrimination and the calibration curve for consistency. Results: A total of 237 patients with pSS [aged 53.00 (44.00, 61.00) years] were included, with 35 pSS-MN patients. Based on clinical practice and multivariable logistic regression analysis, seven variables associated with pSS-MN were selected, including white blood cells, creatine, complement 3, rheumatoid factor, antinuclear antibodies, anti-SSA antibody, and interstitial lung disease. The area under the ROC curve was 0.860 (95% confidence interval: 0.796-0.919), indicating good predictive power. In addition, the nomogram exhibited excellent performance, as demonstrated by the calibration curve and decision curve analysis. Conclusion: This study developed a risk prediction nomogram for MN in patients with pSS, with high predictive power. It may be used to improve the management of patients with pSS.

Membranous lupus nephritis secondary to secukinumab therapy: A case report and literature review.

The interleukin (IL)-17 axis is involved in many inflammatory and autoimmune diseases. Secukinumab, an IL-17 inhibitor, has been approved for psoriasis treatment. There are accumulating cases of lupus erythematosus induced by IL-17 inhibition. Lupus nephritis after IL-17 inhibition has not been reported. We report the case of a 57-year-old man who developed membranous lupus nephritis after secukinumab treatment for psoriasis. Anti-SSA and PM-Scl antibodies were positive. dsDNA, anti-Smith, and anti-histone antibodies were negative, and serum complement was low. Secukinumab was discontinued, while tacrolimus was initiated, subsequently switched to cyclosporin, belimumab, glucocorticosteroid, and hydroxychloroquine with a good response. The relationship between lupus erythematosus and IL-17 inhibition requires further research.

Serum uric acid level is associated with glomerular ischemic lesions in patients with primary membranous nephropathy: an analytical, cross-sectional study.

To investigate the relationship between serum uric acid level and glomerular ischemic lesions (GIL) in patients with primary membranous nephropathy (PMN) and identify relevant risk factors. A total of 201 patients with PMN but normal renal function confirmed by renal biopsy executed in the Liaocheng People's Hospital, China, during January 2020-January 2023 were analyzed retrospectively. The enrolled patients were divided into a hyperuricemia group and a normal serum uric acid group (control group) according to their serum uric acid levels. Then, the participants were further divided into a non-GIL group or a GIL group based on the patient's renal biopsy results. The two groups' clinical and pathological data and meaningful indicators for differences were analyzed by binary logistic regression analysis. Additionally, the serum uric acid level prediction value on GIL was investigated using receiver operating characteristic (ROC) curves. Compared with the control group, the hyperuricemia group exhibited high serum uric acid, the prevalence of GIL, serum albumin, the prevalence of hypertension, and low-density lipoprotein cholesterol (LDL) levels (P < 0.05). Compared with the non-GIL group, the GIL group exhibited were older, had enhanced serum uric acid, serum albumin, and an increased prevalence of tubular atrophy/interstitial fibrosis (TA/IF), arteriolosclerosis, and low eGFR levels (P < 0.05). The binary logistic regression analysis revealed that the serum uric acid and the TA/IF are independent risk factors of GIL (P < 0.05). The AUC of ROC of GIL of PMN patients, predicted based on the serum uric acid concentration, was 0.736 (P < 0.05), wherein the threshold = 426.5 µmol/L and the Youden's index = 0.41. Serum uric acid concentration and the TA/IF are independent risk factors of GIL in patients with PMN, and the former exhibits prediction value on GIL in patients with PMN.

Anti-contactin 1 Antibody-associated Membranous Nephropathy in Chronic Inflammatory Demyelinating Polyneuropathy with Several Autoantibodies.

A 50-year-old man diagnosed with anti-contactin 1 (CNTN1) antibody-associated chronic inflammatory demyelinating polyneuropathy (CIDP) was referred to our department for the evaluation of proteinuria. A kidney biopsy revealed membranous nephropathy (MN). Immunohistochemistry for CNTN1 revealed positive granular staining along the glomerular basement membrane, confirming anti-CNTN1 antibody-associated MN. Immunofluorescence showed a full-house pattern, and several autoantibodies, such as anti-nuclear antibody, anti-double-strand DNA antibody, and anti-cardiolipin antibody, were detected in the patient's serum. Although limited autoantibodies have been investigated in some of the reported cases, a variety of autoantibodies might be produced in anti-CNTN1 antibody-associated CIDP, accompanied by MN.

Prevalence and immunopathologic characteristics of seropositive and seronegative hepatitis B virus-associated membranous nephropathy: a retrospective study of 420 biopsy-proven cases.

BACKGROUND: This retrospective study aims to investigate the prevalence and immunopathologic characteristics of seropositive and seronegative hepatitis B virus-associated membranous nephropathy (HBV-MN). METHODS: Clinicopathologic and serologic records of 420 patients with histologically confirmed HBV-MN between January 2014 and July 2021 were examined to determine the prevalence of seropositive and seronegative HBV-MN. Serum anti-PLA2R antibody testing was conducted on 280 patients with HBV-associated membranous nephropathy (HBV-MN) from August 2018 to July 2021. Immunopathologic characteristics of HBV-MN patients and anti-PLA2R antibody positivity were analyzed. RESULTS: Among 420 pathologically confirmed HBV-MN patients, 230 (54.8%) were seropositive for HBV. The seropositive group exhibited higher blood creatinine values and incidence of liver function abnormalities than the seronegative group (p < .05). Serum anti-PLA2R antibody testing on 280 HBV-MN patients revealed a total positive rate of 44.6%, with the seronegative group showing a significantly higher rate (62.6%) compared to the seropositive group (32.1%) (p < .01). The anti-PLA2R antibody-positive group displayed higher levels of urine protein (p < .05), serum cholesterol (p < .01), and IgG4 subtypes (p < .05) compared to the negative group. Additionally, the positive group had significantly lower levels of serum albumin and IgG than the negative group (p < .01). CONCLUSIONS: This comprehensive study reveals a significantly higher prevalence of seronegative HBV-MN than previously thought. The blood creatinine values and incidence of liver function abnormalities was higher in the serology-positive group than in the serology-negative group. Notably, the seronegative group displayed a higher positive rate of anti-PLA2R antibodies compared to the seropositive group, indicating distinctive clinical and immunopathologic features.

Two successful pregnancies in a membranous nephropathy patient: Case report and literature review.

BACKGROUND: Pregnancy in patients with nephrotic syndrome presents enormous challenges to both the mother and fetus, and there are no treatment guidelines for these patients. METHODS: We show a case of a woman with anti-PLA2R antibody-positive membranous nephropathy who did not have a kidney biopsy. Her clinical course during both pregnancies was closely followed and her medications were guided. RESULTS: She gave birth to 2 healthy babies and her condition was very well controlled with the help of medication. CONCLUSION: Patients with nephrotic syndrome can have successful pregnancies after drug treatment. In addition, similar to the non-pregnant population, percutaneous kidney biopsy is not required for the diagnosis of idiopathic membranous nephropathy (IMN) in pregnant nephrotic syndrome patients with anti-PLA2R antibody positive, but the etiology of secondary MN should be excluded.

PLA2R-positive membranous nephropathy in IgG4-related disease.

BACKGROUND: IgG4-related disease (IgG4-RD) is a fibroinflammatory disease that affects multiple organs, including the pancreas, lacrimal glands, salivary glands, periaortic/retroperitoneum, and kidney. Interstitial nephritis is a typical renal disorder associated with IgG4-RD, but membranous nephropathy is also seen in some cases. CASE PRESENTATION: Herein we report on the case of a 77-year-old male patient with nephrotic syndrome and IgG4-related lung disease. His serum phospholipase A2 receptor (PLA2R) antibody was positive. His renal biopsy specimen was also positive for PLA2R. The renal biopsy specimen showed membranous nephropathy with equal IgG3 and IgG4 immunofluorescence staining and no interstitial nephritis, suggesting IgG4-RD manifesting as membranous nephropathy. CONCLUSIONS: Nephrotic syndrome caused by membranous nephropathy is sometimes associated with IgG4-RD. In such cases, even if serum PLA2R antibody is positive, it should be considered that the membranous nephropathy may be secondary to IgG4-RD.

Idiopathic membranous nephropathy and synchronous mononeuritis multiplex secondary to idiopathic small vessel vasculitis.

Membranous nephropathy has been associated with demyelinating polyneuropathies and antiglomerular membrane disease; however, an association with vasculitic neuropathy has not been described. This case describes a patient with biopsy-proven idiopathic membranous nephropathy and synchronous mononeuritis multiplex secondary to idiopathic small vessel vasculitis, who presented with lower limb microvascular ischaemia, peripheral neuropathy and active urinary sediment. Her extensive non-invasive screening for immunological disease and radiological investigations for occult malignancy were unremarkable. The patient received intravenous methylprednisolone and intravenous rituximab induction therapy resulting in complete remission of both the idiopathic membranous nephropathy and small vessel vasculitis at 7 months post treatment.

Prognostic value of neutrophil-to-lymphocyte ratio on proteinuria remission in patients with idiopathic membranous nephropathy.

BACKGROUND: As a novel marker of inflammation, the neutrophil-to-lymphocyte ratio (NLR) has been studied in various diseases. However, NLR in idiopathic membranous nephropathy (IMN) has been rarely studied. We sought to assess the role of NLR in predicting proteinuria remission in IMN. METHODS: This retrospective study involved 561 patients with IMN from January 2018 to December 2022 in Department of Nephrology of Wuhan Central Hospital. All baseline data were collected before the immunosuppressive regiment was administered. The Cox proportional hazards model and Kaplan-Meier curve were applied to assess the prognostic value of NLR for proteinuria remission. RESULTS: The area under the receiver operating characteristic curve revealed that the optimal cut-off NLR value for predicting proteinuria non-remission was 2.63, with a sensitivity and specificity of 58.2% and 72.7%, respectively. Kaplan-Meier curves showed a lower rate of proteinuria remission in patients with high NLR compared with low NLR (Log-rank = 5.04, p = 0.025). Multivariate Cox regression analysis showed that high NLR was an independent risk factor for proteinuria non-remission after adjustment (HR = 1.579, 95% CI 1.052-2.683, p = 0.023). Subgroup analysis indicated that high NLR was a risk factor for proteinuria non-remission especially in IMN patients with 24 h proteinuria ≥ 1 g (HR = 1.818, 95% CI 1.031-2.573, p = 0.012) and chronic kidney disease (CKD) stage 3-4 (HR = 1.935, 95% CI 1.084-2.495, p = 0.015). CONCLUSION: The current study shows that NLR is an independent risk factor for proteinuria non-remission in IMN. More attention should be paid to IMN patients with high NLR, especially for those patients with 24 h proteinuria ≥ 1 g and CKD stage 3-4.

Colquhounia root tablet in the treatment of idiopathic membranous nephropathy with subnephrotic proteinuria.

PURPOSE: Idiopathic membranous nephropathy (IMN) is the most frequent global cause of nephrotic syndrome in non-diabetic people. In clinical practice, An effective and mild treatment for IMN patients with subnephrotic proteinuria has been adopted. Colquhounia root tablet (CRT) is a traditional Chinese medicine that is widely used in China to treat glomerulopathies. In this study, the effectiveness and safety of CRT in the treatment of IMN with subnephrotic proteinuria have been determined by reviewing the clinical records of 44 patients with IMN. METHODS: Retrospective analysis of IMN patients with subnephrotic proteinuria treated with CRT in combination with ACEI/ARB or ACEI/ARB alone. The remission rate (complete or partial remission) was the main outcome observed, and proteinuria, estimated glomerular filtration rate (eGFR), serum albumin levels, and adverse effects were the secondary outcomes. RESULTS: This clinical trial included 44 patients, and the overall remission rates at months 6, 9, and 12 after treatment were 68.2% versus 27.3% (p = 0.016), 72.7% versus 36.4% (p = 0.015), and 77.3% versus 36.4% (p = 0.006) in the treatment and control groups, respectively. The application of CRT treatment was an independent predictor of proteinuria remission (p = 0.024). In addition, in patients who were positive for phospholipase A2 receptor (PLA2R) antibodies, the overall remission rate was higher in the treatment group than in the control group after 9 months of treatment (75% versus 23.08%, p = 0.017). CONCLUSION: This retrospective study illustrates that, based on supportive therapy, CRT could be effective in the treatment of IMN with subnephrotic proteinuria with a good safety profile at the same time.

Hepatitis B Virus-related Membranous Nephropathy with Crescentic Formation in an Inactive Carrier of Positive Hepatitis B Surface Antigen with Undetectable DNA under Anti-viral Treatment.

A man who was an inactive hepatitis B virus (HBV) carrier with positive hepatitis B surface antigen (HBs antigen) and undetectable HBV-DNA under anti-viral treatment developed nephrotic syndrome at 52 years old, and a renal biopsy revealed advanced membranous nephropathy (MN) with focal cellular crescents, interstitial hemorrhaging, and peritubular capillaritis. Immunofluorescence studies demonstrated granular IgG deposition and HBs antigen-positivity along the capillaries. Glomeruli were negative for phospholipase A2 receptor 1. There were no clinical findings of systemic vasculitis. We considered MN combined with small-vessel vasculitis due to HBV infection. These results suggest that HBV-related kidney disease should be considered even in patients with an inactive HBV carrier status under treatment.

The clinicopathological features and renal prognostic factors in pure membranous lupus nephritis-a large series cohort study from China.

BACKGROUND: Membranous lupus nephritis (MLN) is a subepithelial immune deposition or its morphological sequelae with or without mesangial changes. Previous studies on the prognosis of MLN have shown relatively small sample sizes and short follow-up periods. METHODS: Our study was a retrospective analysis of biopsy-proven MLN patients from January 2010 to January 2020 at Jinling Hospital in China. The clinical manifestations, pathological features, and renal outcomes of MLN patients were collected. The endpoint was defined as end-stage kidney disease (eGFR≤15 mL/min·1.73 m2 or need for renal replacement therapy) or a doubling of serum creatinine or an eGFR decline of more than 40%. We used Cox regression to analyze the risk factors for renal outcome and Kaplan-Meier curves were used to analyze renal survival rate. RESULTS: In the total of 2884 lupus patients, we screened 535 MLN patients. 456 MLN patients were recruited with an average age of 34 ± 12 years, 87.8% for female patients and 62.1% patients of nephrotic syndrome with proteinuria of 2.67 g/24h. After follow-up of 78 (IQR, 47.3-113.0) months, 37 (8.1%) patients reached the renal endpoint. The 5-year and 10-year renal survival rates were 95.8% and 89.4%, respectively. 370 patients (81.1%) achieved complete remission, 43 patients (9.4%) had partial remission, and only 43 had no response. 34.4% MLN experienced a relapse. The Cox regression showed the risk factors that affect the renal prognosis include male, hypertension history, anemia, high uric acid, acute kidney injury, and interstitial fibrosis in the renal pathology. CONCLUSIONS: MLN mostly manifested as nephrotic syndrome, with few renal dysfunctions. Although MLN had a high relapse rate, most patients had a response to immunosuppressants and had a good renal outcome.

Long-term Outcomes in Patients with Membranous Nephropathy: A Retrospective Cohort Study in Iran.

INTRODUCTION: Membranous nephropathy (MN) has variable clinical outcomes, ranging from spontaneous remission to slow progression to kidney failure. Since the clinical outcomes of MN have not been studied in a large sample size in Iran, this study was designed to evaluate the outcome of patients diagnosed with MN at Hasheminejad Kidney Center (HKC), Tehran. METHODS: In this retrospective cohort study, 1086 patients with a diagnosis of MN who were biopsied between 1998 and 2018 in HKC were evaluated through a review of medical records for baseline clinical and laboratory characteristics at the time of biopsy and through a review of follow-up charts and phone calls for the evaluation of clinical outcomes. Of these patients, 551 could be followed for clinical outcomes. The composite outcome included kidney loss (hemodialysis, transplantation, or death). The effect of demographic, clinical, laboratory, and pathological variables on kidney survival was determined by the Cox-regression model using SPSS-16 software at a significance level of .05. RESULTS: Sex (P < .05), higher weight (P < .05), older age (P < .001), hypertension (P < .001), higher baseline proteinuria and lower glomerular filtration rate (GFR) at the onset of the disease were associated with kidney failure (P < .001). A higher percentage of interstitial fibrosis, tubular atrophy, global sclerosis, and a higher pathological class of membranous nephropathy were significantly associated with disease outcome in the univariate Cox-regression analysis (P < .001). Kidney survival rates at 5, 10, and 15 years were 86%, 74%, and 56%; respectively. CONCLUSION: Our study suggests that baseline demographic, clinical and laboratory factors affect kidney outcomes. Patients who are considered high-risk based on the criteria listed above may need to be candidates for more aggressive therapy.  DOI: 10.52547/ijkd.7373.

Malignancy-associated membranous nephropathy: focus on diagnosis and treatment.

BACKGROUND: The clinicopathological features of malignancy-associated membranous nephropathy have been described previously, but information about diagnosis and treatment remains limited. METHODS: Patients with malignancy-associated membranous nephropathy in a tertiary hospital in China between June 2012 and October 2021 were retrospectively reviewed. RESULTS: Forty-two patients with malignancy-associated membranous nephropathy were identified. Compared to patients with idiopathic membranous nephropathy, patients with malignancy-associated membranous nephropathy were older and less frequently showed glomerular phospholipase A2 receptor staining (37.9% vs 85.0%) and IgG4 predominant deposition (66.7% vs 95.0%). At diagnosis of membranous nephropathy, the malignancy was unknown in 67% (28/42) of patients and was detected only by tumor screening. Among the 19 patients with concurrent diagnosis of cancer and biopsy-proven membranous nephropathy, 15 received anticancer treatment alone initially. Six of the 10 patients who attained cancer remission achieved remission of membranous nephropathy, while none of the 5 patients without remission of cancer did, suggesting a causal relationship between the two diseases. Some patients with persistent or relapsing membranous nephropathy following cancer remission achieved remission of membranous nephropathy after immunosuppressive therapy. Over a median follow-up of 24 months, 25% (10/40) of patients died, mainly due to neoplasia. CONCLUSIONS: Tumor screening is important in patients with membranous nephropathy, especially in elderly patients and patients with negative phospholipase A2 receptor or non-IgG4 predominant deposition. Remission of membranous nephropathy can be observed following remission of cancer in some cases. Immunosuppressive therapy may be considered if membranous nephropathy does not remit after remission of cancer.

First case report of PLA2R-related monotypic (IgG-κ positive) membranous nephropathy concurrent with leukocyte chemotactic factor 2 amyloidosis.

BACKGROUND: Membranous nephropathy (MN) is a major pattern of nephrotic syndrome (NS) in adults. Some MN have secondary causes and some may be accompanied with other glomerular diseases. MN patients coexisting with amyloidosis are very rare, and mostly was polytypic MN. Herein, we describe the first report which identifying monotype PLA2R-MN (κ light chain) concurrent with leukocyte chemotactic factor 2 amyloidosis (ALECT2). This rare case highlights the importance of renal pathology for diagnosis. CASE PRESENTATION: We describe a case of a 60-year-old male patient with persistent proteinuria and low serum albumin for nine months. No monoclonal component was revealed by serum and urine immunofixation electrophoresis but serum PLA2R antibody was positive. The patient was empirically treated with Leflunomide and Losartan, but edema was not improved. The diagnosis of renal pathology is PLA2R-related monotypic (IgG-κ positive) MN concurrent with ALECT2. Methylprednisolone, cyclosporine A and anticoagulant (rivaroxaban) were prescribed resulting in a complete remission of NS. CONCLUSIONS: MN patients concurrent with ALECT2 presented massive proteinuria or NS. When nephrotic range proteinuria is present in ALECT2, it is important to consider that it may be due to a concomitant underlying nephropathy especially MN and treated according to MN will get good therapeutic effect.

Calcineurin inhibitors or cyclophosphamide in the treatment of membranous nephropathy superimposed with FSGS lesions: a retrospective study from China.

BACKGROUND: Cyclophosphamide (CTX) and calcineurin inhibitors (CNIs) based regimens are recommended as immunosuppressive therapies for patients with idiopathic membranous nephropathy (IMN). Focal and segmental glomerular sclerosis (FSGS) lesions, which are common in membranous nephropathy (MN), are poor predictors of outcome. This study compared the differences of prognosis between two regimens in patients with IMN combined with FSGS lesions. METHODS: This retrospective study enrolled 108 patients with biopsy-proven IMN, accompanied with FSGS lesions, nephrotic syndrome and an estimated glomerular filtration rate (eGFR)≥60 mL/min/1.73 m2 who were treated with CTX or CNIs. We used propensity score matching (PSM) for balancing the confounding variables. RESULTS: During follow-up, 10 patients (10/55 [18.2%]; nine males) in the CNIs group showed a 50% decline in eGFR; eight had a not otherwise specified variant. Patients initially treated with CNIs had a significantly higher risk of progression to the primary outcome and a lower probability of complete or total remission. The relapse rate was higher in patients who initially received CNIs- than in those who received CTX-based treatment. Before PSM, age and 24-h urine protein level differed significantly between the groups. The PSM model included data from 72 patients. Worse outcomes were also noted among patients who initially received CNIs than those who received CTX-based treatments after matching. CONCLUSIONS: Patients with MN combined with FSGS lesions have a higher risk of renal functional decline and a higher rate of relapse after CNIs than after CTX therapy.

IgG4-Related Membranous Nephropathy with Acute Nephrotic Syndrome During Successful Steroid Maintenance Treatment for Type 1 Autoimmune Pancreatitis.

BACKGROUND Immunoglobulin G4 (IgG4)-related diseases (IgG4-RD) are systemic fibroinflammatory diseases that can develop asynchronously in multiple organs. IgG4-related kidney disease (IgG4-RKD) is generally characterized by tubulointerstitial nephritis but can also manifest as membranous nephropathy without tubulointerstitial nephritis. IgG4-related membranous nephropathy can present as a phenotype of systemic disorders, including autoimmune pancreatitis-associated diabetes mellitus; however, its clinical features remain unclear. CASE REPORT A 56-year-old Japanese man presented to our university hospital with bilateral edema of his lower legs. He had received a diagnosis of type 1 autoimmune pancreatitis and associated diabetes mellitus 16 months prior. He was successfully treated with oral glucocorticoids 25 mg/day of prednisolone as an initial dose, followed by titration down to a maintenance dose (5 mg/day), without recurrence of autoimmune pancreatitis. The pancreas showed atrophy and required basal-bolus insulin therapy owing to insulin insufficiency. Massive proteinuria and hypoalbuminemia with nephrotic syndrome on examination led to a renal biopsy to investigate the etiology and diagnosis of IgG4-RKD. Methylprednisolone and cyclosporine A were successfully administered to ameliorate the proteinuria and control systemic IgG4-RD with IgG4-related membranous nephropathy. CONCLUSIONS Ig4-RKD occurred despite maintenance treatment with prednisolone monotherapy and was controlled with methylprednisolone and cyclosporine A. Measurement of clinical parameters, including proteinuria, was important, and a renal biopsy finally established the diagnosis of IgG4-RKD. IgG4-RKD can present with progressive glomerular lesions and can be latent in cases diagnosed with diabetic kidney disease, particularly in patients with insulin insufficiency.

Serum PLA2R antibody as a predictive biomarker for venous thromboembolism risk in primary membranous nephropathy.

BACKGROUND: Patients with nephrotic syndrome are at high risk of venous thromboembolism (VTE), especially for primary membranous nephropathy (PMN). The phospholipase A2 receptor (PLA2R) is a marker of primary membranous nephropathy activity. This study investigated the predictive value of PLA2R antibodies in PMN for VTE. METHODS: In this retrospective study, we included 97 PMN patients and evaluated the predictive value of serum PLA2R antibodies for VTE risk. Lower extremity venous ultrasound, renal vein ultrasound, or spiral computed tomography pulmonary arteriography were used to assess VTE events. Serum anti-PLA2R antibodies were detected by enzyme-linked immunosorbent assay (ELISA). The risk of VTE was stratified according to serum albumin levels. RESULTS: Twenty PMN patients (21%) had thromboembolic events. Eight (15%) of patients with serum albumin >25g/l developed VTE, 6 of whom were positive for serum PLA2R antibodies. Positive serum PLA2R antibodies were significantly associated with VTE events in patients with serum albumin >25g/l (p=0.01). Age, sex, blood creatinine, serum albumin, and 24-h urine protein levels were not statistically different between the two groups. Kaplan-Meier analysis using the log-rank test revealed anti-PLA2R positive membranous nephropathy patients had more probability of VTE events than anti-PLA2R negative patients. Univariate Cox proportional hazards analysis revealed that lnPLA2R-Ab is an unfavorable predictor for VTE events in patients with serum albumin >25g/l (hazard ratio (HR) 2.1, p=0.01). CONCLUSIONS: The PLA2R antibody was a risk predictor for thromboembolic events in patients with primary membranous nephropathy with serum albumin >25g/l.