Deep learning-based framework for the distinction of membranous nephropathy: a new approach through hyperspectral imagery.

BACKGROUND: Common subtypes seen in Chinese patients with membranous nephropathy (MN) include idiopathic membranous nephropathy (IMN) and hepatitis B virus-related membranous nephropathy (HBV-MN). However, the morphologic differences are not visible under the light microscope in certain renal biopsy tissues. METHODS: We propose here a deep learning-based framework for processing hyperspectral images of renal biopsy tissue to define the difference between IMN and HBV-MN based on the component of their immune complex deposition. RESULTS: The proposed framework can achieve an overall accuracy of 95.04% in classification, which also leads to better performance than support vector machine (SVM)-based algorithms. CONCLUSION: IMN and HBV-MN can be correctly separated via the deep learning framework using hyperspectral imagery. Our results suggest the potential of the deep learning algorithm as a new method to aid in the diagnosis of MN.

Efficacy and Safety of Long-Term Corticosteroid Monotherapy in 26 Cases of Nephrotic Syndrome with Biopsy-Proven Membranous Nephropathy Induced by Seronegative Hepatitis B Virus-Associated Glomerulonephritis.

BACKGROUND: Hepatitis B virus-associated glomerulonephritis (HBV-GN) can occur in patients with negative HBV serological antigens. Little is known about the treatment of seronegative HBV-GN (sn HBV-GN). The aim of this prospective study was to evaluate the efficacy and safety of corticosteroids in the treatment of sn HBV-GN. METHODS: Twenty-six patients with nephrotic syndrome induced by seronegative HBV-associated membranous nephropathy were enrolled. The patients were given methylprednisolone (0.8 mg/kg/day) for 12-24 weeks, tapered by a 2-mg reduction every 1-3 months. Patients were followed up for 6-36 months. Complete remission (CR) was defined as proteinuria <0.3 g/24 h. Partial remission (PR) was defined as proteinuria of 0.3-3.5 g/24 h that was reduced ≥50% of the baseline level. RESULTS: The effective remission (including CR and PR) rates of nephrotic syndrome were 23.1%, 61.5%, 73.1%, 76.2%, 90.5%, and 81.0%, respectively, after 1, 3, 6, 12, 24, and 36 months. Nineteen patients achieved effective remission after 11.68 ± 7.15 months. The level of serum albumin improved from 24.34 ± 6.71 g/L at baseline to 39.61 ± 7.45 g/L at the 36th month significantly. After treatment, the level of serum Cr was similar to the baseline. Only 2 patients relapsed. The primary adverse reaction was infection. None of the patients showed evidence of HBV replication. CONCLUSION: The long-term middle-dose corticosteroid therapy without antiviral drugs is effective and safe for membranous sn HBV-GN patients. For sn HBV-GN patients, the monitoring of HBV DNA and HBV markers in the serum is necessary during the corticosteroid monotherapy. TRIAL REGISTRATION: The Chinese Clinical Trial Registry (ChiCTR1900022518).

Profile of glomerular diseases associated with hepatitis B and C: A single-center experience from India.

Hepatitis B and C are known to affect kidneys in a number of ways. Glomerular diseases associated with hepatitis B and C include membranous nephropathy (MN), membranoproliferative glomerulonephritis (MPGN), focal segmental glomerulosclerosis, immunoglobulin A nephropathy, rarely amyloidosis, and fibrillary and immunotactoid glomerulopathy. In a retrospective analysis of kidney biopsy of 534 patients, we found 16 (2.9%) patients of hepatitis B and 11 (2.05%) patients of hepatitis C with glomerular disease. The most common form of glomerulonephritis in hepatitis B patient was MN and in hepatitis C patient was MPGN.

Successful treatment of occult hepatitis B virus infection related membranous nephropathy after entecavir therapy.

We have reported a case of occult hepatitis B virus infection (OBI) associated membranous nephropathy (MN) with complete remission under an ongoing 3.5-year entecavir monotherapy. A 59-year-old man with a 3-year history of liver cirrhosis was introduced to our department because of oliguria, proteinuria and microscopic haematuria. He, with negative serum HBV surface antigen, was not detected HBV DNA in his serum. Renal biopsy was performed and was compatible with a diagnosis of hepatitis B virus-related membranous nephropathy (HBV-MN). The patient was prescribed diuretics and intravenous albumin, and his ascites and oedema remitted gradually. At the same time, entecavir 0.5 mg per day was started. Entecavir treatment was continuing for 3.5 years and finally resulted in complete remission of proteinuria. This suggests that entecavir monotherapy may induce and maintain complete remission of MN associated with OBI.

Seroconversion of hepatitis B envelope antigen by entecavir in a child with hepatitis B virus-related membranous nephropathy.

Membranous nephropathy (MN) is caused by subepithelial deposition of immune complexes in the glomerular basement membrane, with secondary MN arising in association with infection. In secondary MN caused by hepatitis B virus (HBV), seroconversion has been known to occur after the onset of MN, particularly in children. In patients with high serum concentrations of HBV DNA, treatment with interferon-α2b or a nucleoside analog has been reported to induce seroconversion and suppress HBV-DNA levels. We treated a 7-year-old boy who presented with proteinuria and liver dysfunction. He had a history of HBV infection since shortly after birth, as his mother was HBV-positive, and he was neither vaccinated nor treated with immunoglobulin at birth. Chronic hepatitis related to HBV was diagnosed following percutaneous needle biopsy of the liver. Percutaneous renal biopsy revealed HBV-related glomerulonephritis with diffuse global subepithelial and focal segmental mesangial and subendothelial deposits. Therefore, HBV-associated MN was diagnosed. Treatment with the nucleoside analog lamivudine was started to reduce serum HBV-DNA levels, but lamivudine was discontinued and treatment with entecavir was started at a dosage of 0.5 mg/day after 6 weeks because of possible adverse effects. Tests for HB envelope antibody were positive in week 16 of treatment, and proteinuria had resolved by week 22. Elevated levels of aspartate aminotransferase and alanine aminotransferase were seen with both treatments but were probably attributable to the developing immune response to HBV. In the present case, HBV levels needed to be reduced to: 1) lower elevated serum HBV-DNA titers, which put the patient at high risk of hepatocellular carcinoma; and 2) remove the immune complexes causing MN. Use of nucleoside analogs to suppress the HBV load may facilitate early remission of MN, and entecavir therapy did not cause any serious adverse reactions in this case. Given the advent of lamivudine-resistant HBV, entecavir appears promising for patients with elevated serum levels of HBV DNA.

Hepatitis E virus infection as a new probable cause of de novo membranous nephropathy after kidney transplantation.

Hepatitis E virus (HEV) has been identified as a cause of chronic viral hepatitis in immunocompromised patients. Some glomerular diseases were found to be associated with this infection. We report the first case, to our knowledge, of a kidney transplant recipient who developed an HEV infection and de novo membranous nephropathy (MN) concomitantly. The patient displayed a hepatic cytolysis first and a nephrotic syndrome occurred 3 months later. HEV infection was diagnosed upon positive polymerase chain reaction on plasma and stool samples, and renal allograft biopsy revealed de novo MN. Typical causes of MN were definitively excluded. A 3-month course of ribavirin monotherapy allowed the patient to mount a sustained viral response that was rapidly followed by complete remission of the nephrotic syndrome. The chronology of the onset and remission of both diseases is highly suggestive of a causal relationship between hepatitis E and MN.

Remission of HCV-associated glomerulonephritis with pegylated ifn and ribavirin therapy after liver transplantation: case report and literature review.

BACKGROUND: Hepatitis C virus infection is associated with a variety of extrahepatic disorders such as membrano-proliferative glomerulonephritis, which is generally due to cryoglobulinemia. 
 SETTING: We describe the case of one liver transplant recipient who received antiviral therapy (subcutaneous administration of peg-IFN-alpha-2a 180 mcg weekly and oral ribavirin 200 mg thrice a day) for HCV-related membrano-proliferative glomerulonephritis. He presented normal kidney function, non-nephrotic proteinuria (2 g/24 h) and mild hematuria.
 RESULTS: Urinary abnormalities disappeared within a few weeks after the initiation of antiviral therapy; however, combination antiviral therapy was not able to obtain viral clearance. After 11 months, IFN-therapy was interrupted and the patient continued low-dose ribavirin monotherapy (200 mg once per day) for one additional year- remission of proteinuria (<0.3 g/24 h) and hematuria persisted with intact kidney function. Although other mechanisms cannot be excluded, we suggest that ribavirin therapy was critically implicated in the remission of urinary abnormalities in our patient. The existing literature on the association between HCV-associated glomerulonephritis and therapy with ribavirin is reviewed. 
 CONCLUSIONS: Antiviral therapy may be effective in patients with HCV-induced glomerulonephritis. Further evidence is needed to evaluate efficacy and safety of ribavirin monotherapy for HCV-related glomerulonephritis.

EBV-positive diffuse large B-cell lymphoma in a patient with primary Sjögren's syndrome and membranous glomerulonephritis.

BACKGROUND: Sjögren's syndrome is a systemic autoimmune disease in which lymphatic cells destroy the salivary and lacrimal glands. Glomerulonephritis is thought to be a rare occurrence in primary Sjögren's syndrome. Furthermore, concurrent glomerular involvement and lymphoma in patients with Sjögren's syndrome has seldom been reported. CASE PRESENTATION: A 52-year-old woman with primary Sjögren's syndrome developed membranous glomerulonephritis and Epstein-Barr virus-positive diffuse large B-cell lymphoma (DLBCL). She was diagnosed with Sjögren's syndrome based on the dry eyes, dry mouth, positive anti-nuclear antibody test, anti-Ro (SS-A) antibody, salivary gland biopsy, and salivary scintigraphy. Moreover, renal biopsy confirmed the diagnosis of membranous glomerulonephritis. Three months later, her small bowel was perforated with pneumoperitoneum, and the biopsy revealed Epstein-Barr virus-positive DLBCL. CONCLUSIONS: We observed the first case of primary Sjögren's syndrome associated with Epstein-Barr Virus-positive DLBCL and membranous glomerulonephritis. Because of the possibility of malignancy-associated membranous glomerulonephritis in patients with primary Sjögren's syndrome, we should be careful and examine such patients for hidden malignancy.

[The expression and significance of nephrin in hepatitis B virus-associated membranous nephropathy].

OBJECTIVE: To observe the expression of nephrin in hepatitis B virus-associated membranous nephropathy (HBV-MN), and investigate the impairment and significance of podocyte in HBV-MN. METHODS: The protein expression of nephrin in renal biopsy specimens in 35 patients, who were diagnosed as HBV-MN by renal biopsy, was determined by immunohistochemistry and tested by semi-quantitative method. The relationship between the expression of nephrin and clinicopathological data was analyzed. RESULTS: Among the 35 cases with HBV-MN, 6 were in MN phase I, 20 in MN phase II and 9 in MN phase III. A strong intensity expression of nephrin in normal glomerulus was found along capillary loop of glomerulus, while its expression in HBV-MN patients decreased obviously. There was no significantly difference in the expression of nephrin among the different stages of HBV-MN (P > 0.05). The expression of nephrin in different clinical types was significantly different(P < 0.05). The expression of nephrin in patients with nephrotic syndrome was significantly lower than that in patients without nephrotic syndrome (P < 0.01). The expression of nephrin in different grades of 24-hour urinary protein excretion quantity was significantly different(P < 0.05). There was negative correlation between the expression of nephrin and 24-hour urinary protein excretion quantity(r = -0.378, P < 0.05). In the patients with HBV-MN phase II, the expression of nephrin in patients with nephrotic syndrome was also significantly lower than that in patients without nephrotic syndrome (P < 0.01). CONCLUSIONS: The damage of podocytes emerge in the early stage of HBV-MN and the expression of nephrin in HBV-MN patients, especially in patients with nephrotic syndrome, are significantly down regulated. The descended expression of nephrin in HBV-MN patients may promote the production of proteinuria.

Treatment of hepatitis B virus-associated nephropathy.

Epidemiological studies have shown a relationship between hepatitis B virus (HBV) infection and development of proteinuria in some patients (most commonly children), with a predominance for male gender and histological findings of membranous nephropathy on renal biopsy. The presence of immune complexes in the kidney suggests an immune complex basis for the disease, but a direct relation between HBV and membranous nephropathy (or other types of glomerular diseases) remains to be proven. Clearance of HBV antigens, either spontaneous or following antiviral treatments results in improvement in proteinuria. Thus, prompt recognition and specific antiviral treatment are critical in managing patients with HBV and renal involvement. The present review focuses on treatment of HBV with special emphasis given to antiviral therapies, its complications, and dosing in patients with HBV-associated kidney disease.

[Acute inflammatory polyradiculoneuropathy and membranous glomerulonephritis following Epbstein-Barr virus primary infection in a 12-year-old girl]. / Polyradiculonévrite aiguë et glomérulonéphrite extramembraneuse au décours d'une primo-infection à Epstein-Barr virus chez une patiente de 12 ans.

Acute inflammatory polyradiculoneuropathy, or Guillain-Barré syndrome (GBS), is characterized by peripheral nerve demyelination, which leads to rapidly progressive weakness, loss of sensation, and loss of deep tendon reflexes. It is a prototype of postinfectious autoimmune disease, whose pathophysiology is well described in the forms provoked by certain bacteria (molecular mimicry with Campylobacter jejuni), but remains unclear for the forms related to other organisms (cytomegalovirus, Epstein-Barr virus and other herpes group viruses, Mycoplasma pneumoniae). Glomerular lesions can be associated with the neurological symptoms and have also been described after various infections, independently of any signs of polyradiculoneuropathy. We report the observation of a 12-year-old girl who presented with Guillain-Barré syndrome with facial diplegia, ataxia, and intracranial hypertension following Epstein-Barr virus (EBV) primary infection. During the course of the neurological disease, membranous glomerulonephritis (MGN) was diagnosed. The neurological impairment was regressive within 6 months after intravenous immunoglobulin treatment followed by intravenous then oral corticosteroid administration. Viremia remained high more than 6 months after the onset of symptoms. Glomerulopathy progressed independently and finally required immunosuppressant medication with cyclosporine. EBV might be the factor that triggered the autoimmune disorders, as previously reported for systemic lupus erythematosus and multiple sclerosis in children. To the best of our knowledge, this association of 3 conditions (GBS, MGN, and EBV primary infection) has never been reported in the literature.

Membranous nephritis associated with acquired cytomegalovirus infection in a 19-month-old baby.

Membranous nephritis (MN) is a rare form of glomerulonephritis in childhood, with an incidence of 0.8 to 6.7% based on renal biopsy specimens. Although the disease is considered to be idiopathic in the majority of cases, especially in adults, MN has been associated with various infectious agents, such as hepatitis Beta virus. The natural history of MN in childhood remains unknown because of its rarity, and to the best of our knowledge, no case of MN linked to cytomegalovirus (CMV) infection in an immunocompetent child has been described to date. We report here a 19-month-old female infant who presented with a maculopapular rash, fever, and nephritic-nephrotic syndrome. Virology tests for infectious diseases revealed a recent CMV infection. The renal biopsy findings were compatible with MN, while PCR analysis of the renal tissue specimen was positive for CMV DNA. Antiviral treatment (ganciclovir) resulted in full remission of proteinuria and hematuria. Two years after the initial diagnosis, the child remains well and asymptomatic without clinical or laboratory evidence of the disease.

Complete remission of nephrotic syndrome of hepatitis B virus-associated membranous glomerulopathy after lamivudine monotherapy.

We present the case of a 22-year-old male with chronic hepatitis B virus (HBV) infection, who developed nephrotic syndrome and had complete remission after lamivudine monotherapy. Renal biopsy showed membranous glomerulopathy, and the serum titer of HBV DNA increased to 1,130,000 copies/mL. As symptomatic therapy with angiotensin converting enzyme inhibitors did not improve the nephrotic syndrome, lamivudine 100 mg per day was started. His alanine aminotransferase level normalized 2 months after treatment, then hepatitis B e antigen seroconversion developed and serum HBV DNA became undetectable. His proteinuria improved subsequently and his leg edema disappeared completely 6 months after treatment. Neither hepatitis nor nephrotic syndrome had relapsed by month 13 when he came for follow-up. This suggests that lamivudine monotherapy may induce and maintain complete remission of membranous glomerulopathy associated with hepatitis B.

[Podocyte depletion in children with hepatitis B virus-associated membranous nephropathy].

OBJECTIVE: Hepatitis B virus-associated membranous nephropathy (HBV-MN) is a disease characterized by podocytopathy. Podocyte is a terminally differentiated cell with limited capability of proliferation. Thus, damage of podocyte might result in decreased cell number, and then lead to the development of marked proteinuria and glomerulosclerosis. The present study aimed to investigate the changes of glomerular podocyte number in the children with hepatitis B virus-associated membranous nephropathy (HBV-MN), and their significance in the pathogenesis of HBV-MN. METHODS: Podocytes were identified through specific immunohistological staining of Wilms tumor gene protein 1 (WT1), a characteristic marker for podocyte nuclei, and podocyte numerical density (Nv), mean glomerular tuft volume (V) and the podocyte number per glomerulus (Npodo) were estimated through Weibel-Gomez method in 19 children with biopsy-proven HBV-MN and 8 children with thin basement membrane disease (control group), and analyses were made for possible correlation with clinical, serological and pathological data. RESULTS: Among the 19 cases with HBV-MN, 3 showed microvillus-like foot process of podocytes, granular degeneration of podocyte were found in 4 cases, vacuolization in 1 case and podocyte detachment in 2 cases. Nv and Npodo were significantly decreased in children with HBV-MN compared with control group (t = 12.851, P = 0.0002 and t = 6.433, P = 0.0002, respectively). Moreover, the number of podocytes decreased more significantly in patients with stronger HBsAg deposition (> ++) than those with weak HBsAg deposition (< or = ++), P = 0.004, but no significant difference was found between patients with phase III or IV of HBV-MN and those with phase Ior II in podocyte number per glomerulus (P = 0.5262) and podocyte numerical density (P = 0.3564). Podocyte numerical density decreased more significantly in patients with massive proteinuria (> or = 2 g/24 h) than those with moderate proteinuria (< 2 g/24 h), P = 0.0488. The numbers of podocyte correlated significantly with serum levels of C(3) (r = 0.548, P = 0.028), but did not correlate with serum levels of albumin (r = -0.037, P = 0.891). CONCLUSION: All patients with HBV-MN showed podocyte damage and decreased number per glomerulus, which may play an important role in the pathogenesis of HBV-MN in children.

Study on hepatitis B virus pre-S/S gene mutations of renal tissues in children with hepatitis B virus-associated membranous nephropathy.

This study aims to clarify the prevalence and significance of the emergence of hepatitis B virus (HBV) pre-S/S mutations in children with hepatitis B virus-associated membranous nephropathy (HBVMN). Direct sequencing of polymerase chain reaction products of renal tissue samples that were obtained via percutaneous renal biopsy from seven children revealed the presence of HBV DNA. Seven adr subtypes were analyzed. Deletions in the HBV pre-S region were observed once per seven patients. The deletions were noted in both the pre-S1 (27 bp) and pre-S2 (60 bp) regions. Various point mutations in the HBV pre-S region were detected in all seven patients and proved to be more frequent in the pre-S1 region than in the S2 region. Point mutations in the HBV S region were detected in six patients. Among these mutations, the mutation in the "a" determinant region was noted in five patients. No deletion, however, was observed in the HBV S region. These observations suggested that deletions and point mutations in the HBV pre-S1 and pre-S2 regions and point mutations in the HBV S region, especially the "a" determinant region, are common frequent findings. These results also suggested that HBV pre-S/S region mutations may be involved in the pathogenesis in children with HBVMN.

Lamivudine in hepatitis B-associated membranous nephropathy.

BACKGROUND: Although lamivudine is effective for treatment of chronic hepatitis B (HBV) infection, its potential therapeutic impact on HBV-related membranous nephropathy (MN) in adults has not been characterized. METHODS: We treated 10 HBsAg-positive patients with biopsy-proven MN, elevated serum alanine aminotransferase (ALT), and HBV-DNAemia (group 1), and compared their clinical course with 12 patients diagnosed to have HBV infection, elevated serum ALT, and MN in the pre-lamivudine era (group 2). RESULTS: Baseline demographic and clinical parameters were not different between the 2 groups. In group 1, lamivudine treatment was associated with significant reduction in proteinuria, increase in serum albumin, normalization of ALT levels, and disappearance of circulating HBV-DNA during the first year. Four (40%) and 6 (60%) patients went into complete remission (proteinuria <0.3 g/d) at 6 and 12 months, respectively. In group 2, significant proteinuria persisted during the first year. One (8.3%) and 3 (25%) patients went into remission. Cumulative 3-year renal survival [using end-stage renal disease (ESRD) as primary end point] was 100% in group 1 and 58% in group 2 (P= 0.024, log rank test). Blood pressure control reached the target of below 130/85 mm Hg in both groups. Lamivudine was well tolerated and not associated with any adverse events. Hepatic decompensation or malignancy was not observed during follow-up in both groups. CONCLUSION: HBV-related MN leads to ESRD in a significant proportion of patients before the advent of antiviral therapy. Lamivudine treatment improves renal outcome in HBV carriers with MN and evidence of liver disease.

Hepatitis C virus RNA and core protein in kidney glomerular and tubular structures isolated with laser capture microdissection.

The role of hepatitis C virus (HCV) in the production of renal injury has been extensively investigated, though with conflicting results. Laser capture microdissection (LCM) was performed to isolate and collect glomeruli and tubules from 20 consecutive chronically HCV-infected patients, namely 6 with membranoproliferative glomerulonephritis, 4 with membranous glomerulonephritis, 7 with focal segmental glomerulosclerosis and 3 with IgA-nephropathy. RNA for amplification of specific viral sequences was provided by terminal continuation methodology and compared with the expression profile of HCV core protein. For each case two glomeruli and two tubular structures were microdissected and processed. HCV RNA sequences were demonstrated in 26 (65%) of 40 glomeruli, but in only 4 (10%) of the tubules (P < 0.05). HCV core protein was concomitant with viral sequences in the glomeruli and present in 31 of the 40 tubules. HCV RNA and/or HCV core protein was found in all four disease types. The immunohistochemical picture of HCV core protein was compared with the LCM-based immunoassays of the adjacent tissue sections. Immune deposits were detected in 7 (44%) of 16 biopsy samples shown to be positive by extraction methods. The present study indicates that LCM is a reliable method for measuring both HCV RNA genomic sequences and HCV core protein in kidney functional structures from chronically HCV-infected patients with different glomerulopathies and provides a useful baseline estimate to define the role of HCV in the production of renal injury. The different distribution of HCV RNA and HCV-related proteins may reflect a peculiar 'affinity' of kidney microenvironments for HCV and point to distinct pathways of HCV-related damage in glomeruli and tubules.