Free "small" and IgG-associated "large" hepatitis B e antigen in the serum and glomerular capillary walls of two patients with membranous glomerulonephritis

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.

Membranous nephropathy

Membranous nephropathy is a glomerulopathy, which main affected target is the podocyte, and has consequences on the glomerular basement membrane. It is more common in adults, especially over 50 years of age. The clinical presentation is nephrotic syndrome, but many cases can evolve with asymptomatic non-nephrotic proteinuria. The mechanism consists of the deposition of immune complexes in the subepithelial space of the glomerular capillary loop with subsequent activation of the complement system. Great advances in the identification of potential target antigens have occurred in the last twenty years, and the main one is the protein "M-type phospholipase-A2 receptor" (PLA2R) with the circulating anti-PLA2R antibody, which makes it possible to evaluate the activity and prognosis of this nephropathy. This route of injury corresponds to approximately 70% to 80% of cases of membranous nephropathy characterized as primary. In the last 10 years, several other potential target antigens have been identified. This review proposes to present clinical, etiopathogenic and therapeutic aspects of membranous nephropathy in a didactic manner, including cases that occur during kidney transplantation.

Similarities and Differences between COVID-19-Associated Nephropathy and HIV-Associated Nephropathy

Kidney disease is a major complication of viral infection, which can cause both acute and chronic kidney diseases via different mechanisms such as immune-mediated injury, kidney cell injury from a direct viral infection, systemic effects, and antiviral drug-induced nephrotoxicity. HIV-associated nephropathy (HIVAN), characterized by collapsing focal segmental glomerulosclerosis (cFSGS), has been described 2 decades ago as a major complication of acquired-immunodeficiency syndrome. The pathogenesis of HIVAN has been well studied, including viral entry, host response, and genetic factors. The incidence of this disease has been dramatically dropped with current antiretroviral therapy. In the recent severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) pandemic, acute kidney injury was also found to be a major complication in patients with (coronavirus disease) COVID-19. These patients also developed glomerular disease such as cFSGS in African Americans with apolipoprotein L1 risk alleles, similar to HIVAN. Whether SARS-CoV-2 can infect kidney cells locally remains controversial, but both local infection and systemic effects are likely involved in the pathogenesis of this disease. In this review, we present a comparison of the clinical presentations, pathological findings, disease mechanisms, and potential treatments between HIVAN and COVID-19. Leveraging the knowledge in HIVAN and experimental approaches used to study HIVAN will facilitate the exploration in the pathogenesis of COVID-19-associated kidney disease and improve our management of COVID-19 patients.

Clinicopathological characteristics and prognosis of hepatitis B associated membranous nephropathy and idiopathic membranous nephropathy complicated with hepatitis B virus infection

The main objective of this study is to analyze the clinical and pathological features and prognosis of patients with Hepatitis B associated membranous nephropathy (HBV-MN) and idiopathic membranous nephropathy (IMN) complicated with hepatitis B virus (HBV) infection. This study will provide more basis for diagnosis and prognosis evaluation. A total of 50 patients with HBV-MN were included in this study. 56 IMN patients complicated with HBV infection diagnosed during the same period formed the control group. Parameters including blood routine, urine routine and plasma levels of albumin (ALB), serum creatinine (SCR), blood urea nitrogen (BUN), urea acid (UA), total cholesterol (T-CHO), triglycerides (TG), complement C3 and C4, glutamic pyruvic transaminase (ALT), glutamic pyruvic transaminase (AST), 24-h urinary protein quantification (24 h-TP), renal phospholipase A2 receptor (PLA₂R) and HBV related markers during the hospitalization and outpatient follow-up study period were collected for all the patients. The proportion of male patients was high in both groups. The average age of the HBV-MN group was 37.2 ± 14.187 years old, it was younger compared with the IMN group (P = 0.003). Nephrotic syndrome was the major clinical manifestation among patients. There was no significant difference between the two groups in the levels of anemia, microscopic hematuria, renal dysfunction, liver dysfunction, liver cirrhosis. The level of serum C3 and C4 in the HBV-MN group was lower compared with the IMN group (P = 0.002, P = 0.014). In the HBV-MN group, serum HBV markers were negative in 6 (12%) patients, 4 patients (8%) were positive for PLA₂R in serum, and 5 patients (10%) were positive for PLA₂R in renal tissue. Stronger IgG1 and C1q and weaker IgG4 staining were found in HBV-MN group renal tissues (P = 0.003, P = 0.025, and P = 0.001, respectively). There were no statistical differences compared with serum and renal PLA₂R between HBV-MN and IMN groups (P = 0.098, P = 0.109). During the 1-year follow-up, there was no significant difference in complete remission rate between the two groups (P = 0.7739). Renal biopsy is crucial to diagnose HBV-MN. IgG subtypes in the HBV-MN group were mainly IgG1 deposition, while those in IMN complicated with HBV infection group were mainly IgG4 deposition. When HBV-associated antigen and PLA₂R are present in renal tissue, lower level of serum C3 and C4, high intensity of renal C1q and IgG1 is more supportive of HBV-MN. The positive of PLA₂R in serum and renal tissue in differentiating HBV from IMN complicated with HBV infection remains to be discussed.

Autoimmune Kidney Diseases Associated with Chronic Viral Infections

Autoimmune kidney diseases triggered by viruses are an important cause of kidney disease in patients affected by chronic viral infection. Hepatitis B virus (HBV) infection is associated with membranous nephropathy and polyarteritis nodosa. Hepatitis C virus (HCV) infection is a major cause of cryoglobulinemic glomerulonephritis. Patients with human immunodeficiency virus (HIV) may develop HIV-associated nephropathy, a form of collapsing focal segmental glomerulosclerosis, or various forms of immune-complex-mediated kidney diseases. This article summarizes what is known about the pathogenesis, diagnosis, and management of immune-mediated kidney diseases in adults with chronic HBV, HCV, and HIV infections.

Asian-Pacific clinical practice guidelines on the management of hepatitis B: a 2015 update

Worldwide, some 240 million people have chronic hepatitis B virus (HBV), with the highest rates of infection in Africa and Asia. Our understanding of the natural history of HBV infection and the potential for therapy of the resultant disease is continuously improving. New data have become available since the previous APASL guidelines for management of HBV infection were published in 2012. The objective of this manuscript is to update the recommendations for the optimal management of chronic HBV infection. The 2015 guidelines were developed by a panel of Asian experts chosen by the APASL. The clinical practice guidelines are based on evidence from existing publications or, if evidence was unavailable, on the experts' personal experience and opinion after deliberations. Manuscripts and abstracts of important meetings published through January 2015 have been evaluated. This guideline covers the full spectrum of care of patients infected with hepatitis B, including new terminology, natural history, screening, vaccination, counseling, diagnosis, assessment of the stage of liver disease, the indications, timing, choice and duration of single or combination of antiviral drugs, screening for HCC, management in special situations like childhood, pregnancy, coinfections, renal impairment and pre- and post-liver transplant, and policy guidelines. However, areas of uncertainty still exist, and clinicians, patients, and public health authorities must therefore continue to make choices on the basis of the evolving evidence. The final clinical practice guidelines and recommendations are presented here, along with the relevant background information.

Clinical features of vascular disorders associated with chronic hepatitis virus infection

Hepatitis virus infections can be accompanied by extrahepatic manifestations that may be caused by the host's immune reaction to the viral infection. Vascular involvement is one of these manifestations and is occasionally associated with life-threatening conditions due to systemic organ failure. The unique profile of hepatitis-related vascular involvement is associated with infection by different types of hepatitis viruses. For example, polyarteritis nodosa is more frequently reported in patients with chronic hepatitis B than those with chronic hepatitis C. Similarly, membranous nephropathy is a notable manifestation among hepatitis B virus-positive patients. In contrast, patients infected with hepatitis C virus are at risk for cryoglobulinemia and membranoproliferative glomerulonephritis. Antiviral therapy is necessary to control these kinds of vasculitis related to hepatitis virus infections; however, immunosuppressive agents may be required to treat severe cases. New antiviral drugs for viral hepatitis could improve the prognosis of vascular and renal involvement.

Frequency of CD4+CXCR5+ TFH cells in patients with hepatitis b virus-associated membranous nephropathy

The frequency of different subsets of CD4(+)CXCR5(+) TFH cells and serum cytokine levels were analyzed in a total of 14 patients with newly diagnosed hepatitis B virus-associated membranous nephropathy (HBV-MN), 12 individuals with immune-tolerant HBV infection (HBV-IT) and 12 healthy controls (HC). Serum cytokine levels were measured before and 10-12 weeks after treatment. Significantly higher frequency of CD4(+)CXCR5(+), CD4(+)CXCR5(+)ICOS(+) and CD4(+)CXCR5(+)PD-1(+) TFH cells, and higher serum levels of IL-17A, IFN-γ, IL-2, IL-10, IL-4 and IL-21 were detected in HBV-MN patients compared to the HC. The percentage of CD4(+)CXCR5(+) TFH cells and serum IL-21 level in HBV-MN patients were also higher than the HBV-IT. The percentage of CD4(+)CXCR5(+) TFH cell was negatively correlated with the value of eGFR, and the percentage of CD4(+)CXCR5(+)ICOS(+) TFH cells was positively correlated with the 24-h urinary protein concentration. Notably, the percentage of CD4(+)CXCR5(+)PD-1(+) TFH cells was positively correlated with serum IL-21 level and 24-h urinary protein concentration. Treatment with prednisone or/and immunosuppressive drugs significantly reduced the frequency of CD4(+)CXCR5(+), CD4(+)CXCR5(+)PD-1(+) TFH cells and serum IL-21 level, but increased IL-4 and IL-10 levels in the patients. CD4(+)CXCR5(+) TFH cells, especially CD4(+)CXCR5(+)PD-1(+) TFH cells may participate in the pathogenesis of HBV-MN.

Assessment of differences in the conformational flexibility of hepatitis B virus core-antigen and e-antigen by hydrogen deuterium exchange-mass spectrometry

Hepatitis B virus core-antigen (capsid protein) and e-antigen (an immune regulator) have almost complete sequence identity, yet the dimeric proteins (termed Cp149d and Cp(-10)149d , respectively) adopt quite distinct quaternary structures. Here we use hydrogen deuterium exchange-mass spectrometry (HDX-MS) to study their structural properties. We detect many regions that differ substantially in their HDX dynamics. Significantly, whilst all regions in Cp(-10)149d exchange by EX2-type kinetics, a number of regions in Cp149d were shown to exhibit a mixture of EX2- and EX1-type kinetics, hinting at conformational heterogeneity in these regions. Comparison of the HDX of the free Cp149d with that in assembled capsids (Cp149c ) indicated increased resistance to exchange at the C-terminus where the inter-dimer contacts occur. Furthermore, evidence of mixed exchange kinetics were not observed in Cp149c , implying a reduction in flexibility upon capsid formation. Cp(-10)149d undergoes a drastic structural change when the intermolecular disulphide bridge is reduced, adopting a Cp149d -like structure, as evidenced by the detected HDX dynamics being more consistent with Cp149d in many, albeit not all, regions. These results demonstrate the highly dynamic nature of these similar proteins. To probe the effect of these structural differences on the resulting antigenicity, we investigated binding of the antibody fragment (Fab E1) that is known to bind a conformational epitope on the four-helix bundle. Whilst Fab E1 binds to Cp149c and Cp149d , it does not bind non-reduced and reduced Cp(-10)149d , despite unhindered access to the epitope. These results imply a remarkable sensitivity of this epitope to its structural context.

The role of complement in membranous nephropathy

Membranous nephropathy (MN) describes a histopathologic pattern of injury marked by glomerular subepithelial immune deposits and collectively represents one of the most common causes of adult nephrotic syndrome. Studies in Heymann nephritis, an experimental model of MN, have established a paradigm in which these deposits locally activate complement to cause podocyte injury, culminating in cytoskeletal reorganization, loss of slit diaphragms, and proteinuria. There is much circumstantial evidence for a prominent role of complement in human MN because C3 and C5b-9 are found consistently within immune deposits. Secondary MN often shows the additional presence of C1q, implicating the classic pathway of complement activation. Primary MN, however, is IgG4-predominant and IgG4 is considered incapable of binding C1q and activating the complement pathway. Recent studies have identified the M-type phospholipase A2 receptor (PLA2R) as the major target antigen in primary MN. Early evidence hints that IgG4 anti-PLA2R autoantibodies can bind mannan-binding lectin and activate the lectin complement pathway. The identification of anti-PLA2R antibodies as likely participants in the pathogenesis of disease will allow focused investigation into the role of complement in MN. Definitive therapy for MN is immunosuppression, although future therapeutic agents that specifically target complement activation may represent an effective temporizing measure to forestall further glomerular injury.

A case of adefovir-induced membranous nephropathy related to hepatitis B caused by lamivudine-resistant virus after liver transplant due to Byler's disease

We report on how adefovir-induced membranous nephropathy related to hepatitis B was caused by lamivudine-resistant virus after a liver transplant due to Byler's disease. In 1980, a 2-year-old girl was diagnosed with Byler's disease (familial progressive familial intrahepatic cholestasis). In 1994 (at the age of 14 years) she underwent a liver transplant with her father as the donor. In 2003, hematuria and proteinuria appeared and shortly afterwards her renal function rapidly decreased. A renal biopsy showed atypical membranous nephropathy, which suggested the possibility of a secondary renal disease. The patient had suffered from chronic hepatitis type B (HBV). In 2001 she was administered lamivudine which is an antiviral drug; it was around this time that hematuria and proteinuria appeared as well as an increase of the virus titer. We believed the HBV-related membranous nephropathy was the cause of the virus titer and the renal histology. We concluded that the patient's condition had become resistant to lamivudine medication. Therefore, in February 2004 we administered adefovir, a new drug at the time, to treat the HBV. In April 2004, the HB virus titer decreased and the hematuria and proteinuria decreased. The patient's renal function also showed improvement. HBV-associated nephropathy is caused by HBV antigen deposition in the glomeruli. Generally the first choice of treatment is antivirus therapy. There are many reports demonstrating that administration of interferon and lamivudine are effective; however, there are few reports that show adefovir as an effective treatment for HBV-associated nephropathy.

Hepatitis B virus-associated glomerular nephritis in East Asia: progress and challenges

BACKGROUND

Hepatitis B virus-associated glomerular nephritis (HBV-GN) is the most common secondary glomerulonephritis in East Asia. Part of the patients developed to renal insufficiency within 10 years, which cause a great burden for patients' family and society.

METHODS

We reviewed basic and clinical research work in China, Japan, Korea, and Mongolia, eastern part of Asia. Comparisons between data from East Asia and those from other regions were made.

RESULTS

The genetic variations conferring susceptibility to HBV-GN and disease progression as well as the pathogenic role in HBV-GN progression were investigated. Clinical features of HBV-GN in East Asia were different from that of other regions in the world. Clinical trials showed that treatment with anti-viral agents was effective to promote the disease remission.

CONCLUSION

HBV-GN remains a great challenge to East Asian nephrologists. In-depth basic studies and multi-centered clinical trials are needed in the future.

Target antigens and nephritogenic antibodies in membranous nephropathy: of rats and men

Membranous nephropathy, a disease characterized by an accumulation of immune deposits on the outer aspect of the glomerular basement membrane, is the most common cause of idiopathic nephrotic syndrome in white adults. In the rat model of Heymann nephritis, the target antigen of antibodies is megalin, a multiligand receptor expressed at the podocyte cell surface. This review summarizes key findings provided by this experimental model and by our discovery of neutral endopeptidase being the alloantigen involved in neonatal cases of membranous nephropathy. We discuss the role of alloimmunization as a new mechanism of renal disease and the approach that we use to identify new podocyte antigens. We also summarize current knowledge on the mechanism of proteinuria, with special emphasis on the role of complement. In conclusion, substantial progresses have been made in understanding molecular mechanisms of membranous nephropathy, which should lead to novel therapeutic approaches.

Virological features of hepatitis B virus-associated nephropathy in Japan

Hepatitis B virus (HBV)-associated nephropathy is considered as an immune-mediated disorder which is dependent on interactions between viral, host, and environmental factors. But there are few reports that investigated the relationship between the development of HBV-associated nephropathy and HBV genotypes and the mutations. To clarify the relationship between nephropathy and HBV genotype in Japan, six male patients with HBV-associated nephropathy were examined. The complete genome sequences of HBV were determined directly and the specific mutations associated with the development of HBV-associated nephropathy were examined by comparison of the alignments along with consensus sequences [HBV/A1 (Aa), A2 (Ae), B1 (Bj), B2 (Ba), C1 (Cs) and C2 (Ce)] retrieved from international database. The mean age of the six patients was 33.5 years. HBeAg was found in all patients and serum HBV-DNA levels were relatively high. Histological findings of renal tissues indicated five cases of membranous nephropathy and one membranoproliferative glomerulonephritis. HBV genotypes from the six patients were two HBV/A1, two A2 and two C2, suggesting HBV/A was predominant. G1862T mutation was observed in the two HBV/A1 patients, resulting in the pre-core amino acid substitution with a switch from valine (Val) to phenylalanine (Phe). Only one patient had core deletions. It is concluded that HBV/A may be associated with membranous nephropathy, but little relationship between HBV gene mutations and the development of HBV-associated nephropathy was observed.

Viral hepatitis and proteinuria in an area endemic for hepatitis B and C infections: another chain of link?

BACKGROUND AND OBJECTIVES

Virus hepatitis may lead to nephropathy as one of its multiple extrahepatic manifestations. Proteinuria by dipstick, a simple test in practice, is a useful and cardinal sign of underlying renal abnormalities. The aim of this study was to elucidate the impact of hepatitis B virus (HBV) and/or hepatitis C virus (HCV) infections on the occurrence of proteinuria amongst adults.

DESIGN AND SETTING

A prospective, cross-sectional, community-based study was conducted in an HBV/HCV endemic area of southern Taiwan. Eligible subjects aged 40-65 years (n=9934) underwent testing of hepatitis B surface antigen (HBsAg), HCV antibody (anti-HCV) and other related biochemical profiles. Urinalysis with repeated dipstick for proteinuria detection was performed.

RESULTS

Anti-HCV-positive rate amongst proteinuria subjects was significantly higher than nonproteinuria subjects (9.6% vs. 6.2%, P<0.001). By contrast, HBsAg-positive rate did not differ between subjects with and without proteinuria (13.0% vs. 13.8%, P=0.57). Prevalence of proteinuria amongst anti-HCV-positive subjects (10.2%) was significantly higher than that in HBsAg-positive subjects (6.4%, P=0.004) and in HBsAg-negative or anti-HCV-negative subjects (7.0%, P=0.004). The difference persisted even after excluding diabetics. Multivariate logistic regression analyses showed that diabetes was the most important significant factor associated with proteinuria, followed by hypertension, anti-HCV seropositivity, body mass index, age and triglyceride levels.

CONCLUSION

We demonstrated the significant association between proteinuria and HCV, but not HBV, infection in this HBV/HCV-endemic area.

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.

Molecular pathomechanisms of membranous nephropathy: from Heymann nephritis to alloimmunization

Membranous nephropathy (MN), the most common cause of idiopathic nephrotic syndrome in white adults, is characterized by an accumulation of immune deposits on the outer aspect of the glomerular basement membrane. In Heymann nephritis, the rat experimental model for MN, megalin--the target antigen of the nephritogenic antibodies--is expressed on the surface of podocytes, where immune complexes are formed, leading to complement activation and nephrotic-range proteinuria. However, megalin cannot be held responsible for human MN because it has not been found in human podocytes or detected in subepithelial immune deposits in patients with MN. Several potential antigens have been identified in so-called secondary forms of MN, but there is no real proof that these antigens are pathogenic. In a subgroup of infants with antenatal MN, neutral endopeptidase (NEP) has been identified as the first protein target on human podocytes of nephritogenic antibodies. The infants' mothers became immunized during pregnancy against NEP expressed on syncytiotrophoblastic cells because they were NEP deficient as a result of truncating mutations in the MME gene. Severity of neonatal renal disease was determined by the mothers' IgG response that led to the formation of the membrane attack complex of complement in the subepithelial deposits. Alloimmunization against NEP is a novel pathomechanism of MN that might also account for some cases of MN after renal or bone marrow transplantation. Other types of alloimmunization should be investigated in MN but also in other renal and nonrenal diseases, particularly those that affect the pediatric age.

Existence and significance of hepatitis B virus DNA in kidneys of IgA nephropathy

AIM

To investigate the existence and significance of hepatitis B virus (HBV) DNA in the pathogenesis of IgA nephropathy (IgAN).

METHODS

Fifty cases of IgAN with HBV antigenaemia and/or hepatitis B virus antigens (HBAg, or HBsAg, HBcAg) detected by immunohistochemistry in renal tissues were enrolled in our study. The distribution and localization of HBV DNA were observed using in situ hybridization. Southern blot analysis was performed to reveal the state of renal HBV DNA.

RESULTS

Among the 50 patients with IgAN, HBs antigenemia was detected in 17 patients (34%). HBAg in renal tissues was detected in 48 patients (96%), the positive rate of HBAg, HBsAg, and HBcAg was 82% (41/50), 58% (29/50), and 42% (21/50) in glomeruli, respectively; and was 94% (47/50), 56% (28/50) and 78% (39/50) in tubular epithelia, respectively. Positive HBV DNA was detected in 72% (36/50) and 82% (41/50) cases in tubular epithelia and glomeruli respectively by in situ hybridization, and the positive signals were localized in the nuclei of tubular epithelial cells and glomerular mesangial cells as well as infiltrated interstitial lymphocytes. Moreover, 68% (34/50) cases were proved to be HBV DNA positive by Southern blot analysis, and all were the integrated form.

CONCLUSION

HBV infection might play an important role in occurrence and progress of IgAN. In addition to humoral immune damages mediated by HBAg-HBAb immune complex, renal tissues of some IgAN are directly infected with HBV and express HBAg in situ, and the cellular mechanism mediated by HBV originating from renal cells in situ may also be involved in the pathogenesis of IgAN.

Extrahepatic manifestations of chronic hepatitis B

Several extrahepatic manifestations are associated with chronic HBV infection, many with significant morbidity and mortality. The cause of these extrahepatic manifestations is generally believed to be immune mediated. PAN is a rare, but serious, systemic complication of chronic HBV affecting the small- and medium-sized vessels. PAN is seen more frequently in North American and European patients and rarely in Asian patients. PAN ultimately involves multiple organ systems, some with devastating consequences, though the hepatic manifestations are often more mild. The optimal treatment of HBV-associated PAN is thought to include a combination of antiviral and immunosuppressive therapies. HBV-associated GN occurs mainly in children, predominantly males, in HBV endemic areas of the world, but is only occasionally reported in the United States. In children, GN is usually self-limited with only rare progression to renal failure. In adults, the natural disease course of GN may be more relentless, slowly progressing to renal failure. Immunosuppressive therapy in HBV-related GN is not recommended, but antiviral therapy with alpha-interferon has shown promise. The serum-sickness like "arthritis-dermatitis" prodrome is seen in approximately one third of patients acquiring HBV. The joint and skin manifestations are varied, but the syndrome spontaneously resolves at the onset of clinical hepatitis with few significant sequelae. Occasionally, arthritis following the acute prodromal infection may persist; however, joint destruction is rare. The association between HBV and mixed essential cryoglobulinemia remains controversial; but a triad of purpura, arthralgias, and weakness, which can progress to nephritis, pulmonary disease, and generalized vasculitis, has characterized the syndrome. Finally, skin manifestations of HBV infection typically present as palpable purpura. Though papular acrodermatitis of childhood has been reported to be caused by chronic HBV, this association remains controversial.

Role of hepatitis B virus infection in pathogenesis of IgA nephropathy

AIM: To investigate the role of hepatitis B virus (HBV) in the pathogenesis of IgA nephropathy (IgAN).

METHODS: HBV antigens (HBAg, or HBsAg, HBcAg, and HBeAg) in renal tissues with IgAN were detected by immunohistochemical technique. The distribution and localization of HBV DNA were observed by using in situ hybridization. Southern blot analysis was performed to reveal the state of renal HBV DNA.

RESULTS: Among 100 patients with IgAN, HBs antigenemia was detected in 18 patients (18.00%). HBAg in renal tissues was detected in 31 patients (31.00%), the positive rate of HBAg, HBsAg and HBcAg was 64.52% (20/31), 32.26% (10/31), 32.26% (10/31), respectively in glomeruli. HBcAg was also found in tubular epithelia and interstitia, which was 45.16% (14/31) and 6.45% (2/31), respectively. Five out of six cases with positive HBV DNA by in situ hybridization were proved to be HBV DNA positive by Southern blot analysis, and all were of the integrated form. Eight specimens were demonstrated to be HBV DNA positive by in situ hybridization, which was localized in the nuclei of tubular epithelial cells and glomerular mesangial cells as well as in infiltrated interstitial lymphocytes.

CONCLUSION: There is a relationship between HBV infection and IgAN. In addition to the humoral immune damage mediated by HBAg-HBAb immune complex, the cellular mechanism mediated by HBV originating from renal cells in situ may be also involved in the pathogenesis of IgAN.

Extrahepatic manifestations of chronic viral hepatitis

Hepatitis B (HBV) and C (HCV) viruses are well-recognized causes for chronic hepatitis, cirrhosis, and even for hepatocellular carcinoma. Apart from liver disease, these viral infections are known to be associated with a spectrum of extrahepatic manifestations. The prevalence of clinically significant extrahepatic manifestations is relatively low, but it can be associated with significant morbidity and even mortality. An awareness and recognition of these manifestations is of paramount importance in facilitating early diagnosis and in offering treatment. However, treatments are not necessarily effective, and patients may continue with disabling extrahepatic manifestations. Hepatitis B virus has been well recognized as causing a variety of manifestations that include skin rash, arthritis, arthralgia, glomerulonephritis, polyarteritis nodosa, and papular acrodermatitis. More recently, infection with hepatitis C virus has elicited considerable interest for its role in a spectrum of extrahepatic manifestations. Among the best-reported are cryoglobulinemia, glomerulonephritis, high titer of autoantibodies, idiopathic thrombocytopenic purpura, lichen planus, Mooren's corneal ulcer, Sjögren's syndrome, porphyria cutanea tarda, and necrotizing cutaneous vasculitis. The precise pathogenesis of these extrahepatic complications has not been determined, although the majority represent the clinical expression of autoimmune phenomena.

IgA nephropathy--human disease and animal model

IgA nephropathy is one of the most common chronic glomerulonephritides worldwide. Since the first publication on IgA nephropathy, a number of clinical and pathological investigations have revealed that the clinical course of patients with IgA nephropathy is extremely diverse, with approximately 10-20% of the patients developing end-stage chronic renal failure. Glomerular changes similar to IgA nephropathy have also been observed in patients with Schoenlein-Henoch purpura, and with other diseases such as liver cirrhosis and chronic inflammatory diseases of the lung. The broad spectrum of clinical and pathological features of IgA nephropathy encompasses a syndrome which includes both primary and secondary IgA nephropathy. The common etiology and pathogenesis of primary and secondary IgA nephropathy appear to be closely related to immunological abnormalities in the production of IgA induced by antigenic stimulation of the common mucosal immune system. IgA is one of the most important humoral factors of the mucosal immune defense system and functions as an antibody against various extrinsic and intrinsic substances. This review describes the Arthus type of IgA immune complex deposition in the glomeruli which can result from persistent or repeated increases in circulating IgA immune complexes. The latter occurs as a consequence of overproduction of IgA antibodies and/or impairment in clearance of IgA immune complexes by the mononuclear phagocytic system. The present review also focuses on the biology of the IgA-mediated immune system and on the etiology, pathogenesis, and animal models of IgA nephropathy.

Detection of hepatitis B virus DNA and RNA in kidneys of HBV related glomerulonephritis

Glomerular deposition of hepatitis B virus (HBV) antigens are observed in chronic HBsAg carriers with different glomerulonephritides yet the etiologic role of HBV remains uncertain. We examined the paraffin section of kidney biopsies from 40 chronic HBsAg carriers with membranous nephropathy (MGN), mesangiocapillary glomerulonephritis (MCGN) or IgA nephropathy (IgAN) for HBV DNA and HBV RNA using in situ hybridization (ISH). Glomerular HBV antigens were present in all biopsies by immunofluorescence. HBsAg or HBcAg mRNA was also studied in RNA extracted from frozen renal tissue using a two-step polymerase chain reaction (PCR) following reverse transcription (RT). HBcAg DNA was not easily detected with ISH alone, but was readily found in 31 biopsies (78%) following PCR. HBV DNA was detected mainly in the cytoplasm of proximal tubular epithelia but not in glomerular cells. HBsAg and/or HBcAg mRNA were detected by RT-PCR in extracted RNA from 13 biopsies (33%). The PCR findings were further confirmed by (a) Southern blot hybridization using a cloned HBV probe and (b) absence of PCR product following treating RNA with RNase or omitting the RT. It is plausible that HBV DNA in renal tubules represents endocytosis of HBV DNA in the urinary filtrate and the HBV RNA extracted from kidney biopsies could derive from infiltrating cells bearing HBV RNA. Hence, ISH with specific HBV core gene RNA probe was performed subsequently. HBcAg RNA, localized in the nuclei and cytoplasm of glomerular and tubular cells, was detected in 56%, 20%, and 36% of renal biopsies in chronic HBsAg carriers with MGN, MCGN, and IgAN, respectively. Our findings indicate the presence of viral transcription in glomerular cells and renal tubular epithelia, supporting an etiological role of HBV in some chronic HBsAg carriers who develop coexisting glomerulonephritides.

The frequency of hepatitis B virus infection in Greek patients with various types of glomerulonephritis

The frequency of hepatitis B surface antigen (HBsAg) was studied in the sera of 622 patients with glomerulonephritis (GN). The prevalence of HBs-antigenemia was 2.8% (18/622; eleven adults and seven children); the difference from 2.6% in the general population of Central and Southern Greece was not statistically significant (chi 2 = 0.01; p > 0.50). Two of the 11 HBsAg-seropositive adult patients with GN suffered from IgA nephropathy, one from IgA and membranous glomerulonephritis (MGN), four from diffuse proliferative GN, two from membranous GN and one each from crescentic GN and focal segmental glomerulosclerosis. Five children out of 12 with membranous glomerulonephritis, one out of 24 with IgA nephropathy and one out of 16 with focal segmental glomerulosclerosis had HBs-antigenemia. The frequency of HBs-antigenemia in children with MGN was 41.7%, which is significantly higher than in children with other types of GN (0.9%). All seropositive patients were asymptomatic HBsAg carriers, while one seropositive HBsAg child with MGN suffered from chronic persistent hepatitis. HBsAg was detected by the immunoperoxidase-antiperoxidase (PAP) method in the glomeruli of only 3 children with MGN and HBs antigenemia, while HBcAg was not detected in any case. Our study suggests that in the Greek population there is no increased prevalence of HBs-antigenemia in patients with glomerulonephritis. Moreover, HBsAg was not found to contribute in the pathogenesis of GN in adults but it may be associated with the pathogenesis of membranous GN in children.

Etiology of IgA nephropathy syndrome

Since Berger's original paper on mesangial IgA-IgG deposition with hematuria, there have been a number of clinical and pathological studies regarding IgA immune complexes, the mechanisms of glomerular IgA deposition leading to glomerular injury and animal models of IgA nephropathy. During the last quarter of this century, glomerular changes such as IgA nephropathy have also been observed in cases associated with other diseases, such as systemic lupus erythematosus, Schoenlein-Henoch purpura, liver cirrhosis and chronic inflammatory diseases of the lung. This evidence supports the idea of an IgA nephropathy syndrome. On the other hand, IgA is thought to be an important humoral factor at the mucosal immune system and appears to have an antibody function against various etiologic candidates of extrinsic or intrinsic substances at the mucosal and systemic immune system. Glomerular IgA deposition in IgA nephropathy syndrome is thought to result from elevated levels of circulating immune complexes or aggregated IgA due to an overproduction of polymeric IgA as antibodies in the serum and due to the clearance impairment of IgA immune complexes in the hepatic and splenic phagocytic system. The glomerular IgA subclass is not one-sided, but should be evaluated in comparison with the age of patients at renal biopsy; this indicates the approximate age of onset. Cirrhotic IgA glomerulonephritis is not related to Hepatitis B or C virus infection, but to the pathophysiologic condition of liver cirrhosis. Various etiologic candidates such as viral, microbial, dietary antigens or auto-antigens have been listed and experimental models of IgA nephropathy syndrome have provided some clues in understanding the etiology of primary IgA nephropathy. However much still remains to be clarified and some specific epitopes common among these etiologic candidates will have to be identified.

Binding of bacterial adhesins to rat glomerular mesangium in vivo

Two well characterized bacterial adhesins, the O75X fimbriae of Escherichia coli and the type-3 fimbriae of Klebsiellae, with in vitro affinities to type IV and V collagens, respectively, were used to test whether bacterial components with affinity for glomerular matrix could bind to glomeruli in vivo. The purified fimbrial proteins were injected into rats, and kidney samples were studied by immunofluorescence at two hours to nine months postinjection. The O75X, but not the type-3 fimbriae, formed mesangial deposits that persisted for months. Preincubation of the O75X fimbriae with type IV collagen significantly reduced the glomerular binding. The fimbrial deposits were extracellular, as anti-O75X IgG injected into rats bound to glomeruli. Proteinuria or histological damage could not be detected even after passive or active immunizations of the rats. The results demonstrate that bacterial adhesins may bind in vivo to and persist in glomeruli by their specific affinities. The results also indicate that additional factors provided by the bacteria or the host are needed for glomerular damage to take place.

Membranous nephropathy associated with multiple sclerosis

Membranous nephropathy and multiple sclerosis are believed to be mediated by immune mechanisms. A patient is reported with the first described association of membranous nephropathy and multiple sclerosis. Its significance and possible pathogenetic mechanisms are discussed.

Remission of hepatitis B-associated membranous glomerulonephritis in human immunodeficiency virus infection

Hepatitis B virus (HBV) infection has been associated with several renal diseases, the most common being membranous glomerulonephritis (MGN). The role of concurrent human immunodeficiency virus (HIV) infection in affecting the course of the renal involvement is largely unknown. We report the case of a HIV-infected adult male with chronic HBV-associated MGN who had complete remission of the nephrotic syndrome associated with spontaneous seroconversion from hepatitis B e antigen (HBeAg)-positive to HBeAg-negative. The present case illustrates that HIV infection does not preclude improvement of chronic HBV infection or an associated membranous nephropathy. Such improvement may be dependent on the ability of the host immune system to clear HBeAg.

Circulating HBsAg/IgG complexes in idiopathic chronic glomerulonephritis

We measured HBsAg/IgG complexes (CX) quantitatively by ELISA from HBsAg positive serum of 35 liver disease patients, 15 patients with glomerular diseases (8 membranous glomerulonephritis (MGN) 7 membranoproliferative glomerulonephritis (MPGN), and 50 healthy carriers of HBsAg. HbsAg/IgG CX was detected in 26 out of 35 liver disease patients (74.3%), 5 out of 50 healthy carriers (10%), and one of both 8 MGN patients (12.5%) and 7 MPGN patients (14.3%). HBsAg/IgG CX was big in size and wide spread in the liver disease groups but negligible in the healthy carrier group (41 +/- 2.6 ng/ml, n = 5) and MGN (50 ng/ml, n = 1) and MPGN (42 ng/ml, n = 1) group. In the liver disease group, no one suffered from glomerulopathy even with a wide spectrum of HBsAg/IgG CX. These results suggest that HBsAg/IgG CX in plasma is non causative of MGN and MPGN.

Comparison of class and subclass distribution of antibodies to the hepatitis B core and B e antigens in chronic hepatitis B

The IgG subclasses IgM and IgA1 of antibodies to hepatitis B core antigen (anti-HBc) and hepatitis B e antigen (anti-HBe) were assayed in sera from 82 patients with chronic hepatitis B utilising class/subclass-specific enzyme immunoassays (EIA). The solid-phase was either recombinant hepatitis B core antigen (rHBcAg) or rHBcAg converted to HBeAg by addition of 0.1% SDS with remaining HBcAg antigenicity blocked with monoclonal anti-HBc. Anti-HBc IgG1 was detected in 81 sera at a geometrical mean titre (GMT) of 296,110 x divided by 2.9. Anti-HBc IgG2 was not detected in any of the sera, and anti-HBc IgG3 and IgG4 were detected in 50 and 37 sera, respectively. Anti-HBc IgM and IgA1 were both significantly correlated to the presence of HBV DNA. The predominant antibody to HBeAg was found to be IgG1, being detected in 45 sera with a GMT of 1,035 x divided by 3.3. Anti-HBe IgG2 was not detected in any serum, while anti-HBe IgG3 and IgG4 were found in 8 and 23 sera, respectively. Anti-HBe IgG1, IgG3, and IgG4 were mainly detected in sera positive for anti-HBe in RIA (Abbott). No patient was found positive for anti-HBe IgA1 or IgM. Thus, in contrast to HBcAg, HBeAg does not trigger a persistent IgM and IgA1 response in chronic hepatitis B. The levels of anti-HBe IgG1 and IgG3 were much lower than the levels of anti-HBc IgG1 and IgG3. The presence of anti-HBe IgG4 was significantly correlated to that of anti-HBc IgG4.(ABSTRACT TRUNCATED AT 250 WORDS)

Membranous nephropathy in 52 hepatitis B surface antigen (HBsAg) carrier children in Taiwan

To elucidate the prognosis and the causative viral antigens of hepatitis B virus (HBV)-associated childhood membranous nephropathy (MN), the clinical course and glomerular HBV antigens were studied in 52 HBsAg carrier children with MN (40 boys, 12 girls). With Fab fragments of monoclonal antibodies, hepatitis Be antigen (HBeAg) was detected in the glomerular deposits in 41 (95%) of 43 cases but HBsAg and hepatitis B core antigen (HBcAg) in none. HBeAg was detected in sera from 43 (93%) of 46 children examined. These results suggest that HBeAg plays an important role in the development of MN in HBsAg carrier children. During the follow-up period (mean, 4 years), complete remission was found in 64% and 92% of the patients followed for one and seven years, respectively; only one child had mild renal function impairment. These findings suggest a favorable outcome of HBsAg-associated childhood MN. The patient's age, disease duration, amount of glomerular deposit, focal sclerosis and disease stage appeared to affect the clinical course. HBsAg seroconversion to HBsAg-negative occurred in seven cases, and all (100%) had quick remission in two years. In patients with persistent HBsAg carriage, serum HBeAg status alone did not correlate with remission rate and remission occurred usually before the HBeAg seroconversion to anti-HBe. These findings, together with the predominant horizontal infection in these children in contrast to the frequent vertical (perinatal) transmission from HBsAg carrier mothers in HBsAg carriers in Taiwan, suggest that factors other than HBeAg per se may also play important roles.

Improvement of hepatitis B-associated glomerulonephritis after antiviral combination therapy

A 9-year-old boy with hepatitis B-associated glomerulonephritis and nephrotic syndrome underwent antiviral combination therapy including interferon and acyclovir. Pretreatment evaluation showed that active hepatitis B virus replication with HBsAg, HBeAg, HBV-DNA and DNA-polymerase had occurred for a period of at least 4 years. Signs of liver disease were minimal; serum amino transferases were normal and liver histology showed chronic persistent hepatitis with positive HBcAg, HBeAg and HBsAg immunofluorescence. A kidney biopsy revealed membranous glomerulonephritis with deposition of HBcAg, HBeAg, IgG, C3, C1q and, on electron microscopy, virus-like particles. After 8 weeks of therapy, active viral replication ceased, HBe seroconversion occurred and the nephrotic syndrome disappeared. One year after treatment, the boy was asymptomatic. No viral markers could be detected in the kidney, but low-grade membranous glomerulonephritis persisted with deposition of C1q, IgG and C3, but not HBeAg, HBsAg or HBcAg. Liver histology showed a minimal aspecific portal infiltrate with weak membrane-bound HBsAg immunofluorescence; no HBcAg could be detected. For patients with active viral replication and deposition of HBc, HBe immune complexes in the kidney, antiviral therapy can be beneficial, even in the absence of active liver disease.

IgA nephropathy associated with chronic hepatitis B virus infection in adults: the pathogenetic role of HBsAG

Five adult cases of IgA nephropathy associated with chronic hepatitis B virus infection were studied. Serum HBsAg and anti-HBc were present in five patients and HBeAg in four patients. Glomerular changes were typical of primary IgA nephropathy in four patients, and a mixed picture of IgA and membranous nephropathy was demonstrated in one patient. Immunofluorescence microscopy using polyclonal and monoclonal antibodies against HBsAg, HBcAg, and HBeAg revealed mesangial deposits of HBsAg in renal biopsies from four patients. One renal biopsy showed only mesangial and capillary HBcAg by polyclonal antiserum, and virus-like particles were demonstrated in the intramembranous electron-dense deposits on ultrastructural examination. Mesangial HBeAg was not detected in the renal biopsies from these patients with IgA nephropathy. As for the single patient with a mixed picture of IgA and membranous nephropathy, granular deposits of HBeAg with a distribution similar to IgG were detected in the glomerular capillary walls in addition to the mesangial deposition of HBsAg. These findings suggest that HBsAg rather than HBeAg may play a role of the pathogenesis in some of the adult patients with IgA nephropathy associated with chronic hepatitis B virus infection.

HBeAg/anti-HBe circulating immune complexes in patients chronically infected with hepatitis B virus

An enzyme-linked immunosorbent assay based on the ability of polyethylene-glycol (PEG) fixed on a solid support to adsorb circulating macromolecules (PEG-solid phase test) was developed in order to provide evidence for the existence of immune complexes of HBeAg/anti-HBe (HBeAg/anti-HBe complex) in sera of HBsAg chronic carriers. The method can detect HBeAg in immune complexes whether antigen or antibody is in excess. In the chronic phase of HBV infection, HBeAg/anti-HBe complexes are formed transiently in the course of the disease, unrelated to the phases of virus replication or peaks of hepatocytolysis, or to the histologic picture of liver disease. Our study indicates that this method offers a new approach to the understanding of biological and clinical problems of the HBeAg/anti-HBe antigenic system in chronic HBV infection.

Immunoelectron microscopic localization of membrane attack complex and hepatitis B e antigen in membranous nephropathy

Immunoelectron microscopy was used to localize membrane attack complex (MAC) and hepatitis B e (HBe) antigen in renal tissue specimens from a total of 9 patients with membranous nephropathy (MN); 6 with MN associated with a hepatitis B virus (HBV) infection, 2 with idiopathic MN, and 1 with lupus nephritis. All the patients were proteinuric, and 2 patients were classified as stage I-II, 6 as stage II, and 1 as stage IV. MAC, along with IgG and C3, was distributed within the subepithelial electron dense deposits in all the stages. MAC was also stained in the striated membranous structures within the glomerular basement membrane and mesangial matrix of some patients. In HBV-associated MN, HBe antigen was localized in the subepithelial electron dense deposits of 5 patients, while it was absent from the subepithelial deposits in a patient that was sero-positive for hepatitis B s antigen but negative for HBe antigen. This patient also lacked MAC deposition in these loci. These results suggest that MAC is associated with the formation of subepithelial deposits and proteinuria in MN. In HBV-associated MN, HBe antigen-antibody immune complex makes up the subepithelial deposits and is likely to activate the terminal components of complement in situ.

A renal biopsy study of hepatitis B virus-associated nephropathy in Korea

The pathogenic role of the hepatitis B virus (HBV) infection for glomerulonephritis (GN) is not clear. The frequency of HBsAg has been studied in sera of 732 consecutive patients who have glomerular diseases by using radioimmunoassay. The frequency of HBs antigenemia was 11.9%, which was not different from that in the general population of South Korea. Of the 87 HBsAg seropositive patients with GN, 29 cases with membranoproliferative GN (MPGN) and eighteen with membranous nephropathy (MN) were diagnosed as having HBV-associated nephropathy. Eighty-seven and one-half percent of the adults with MPGN and 80% of the children with MN were HBsAg carries. The morphologic findings and laboratory data in cases with HBV-associated MPGN and MN did not differ significantly from those observed in patients with MPGN and MN without circulating HBsAg. Yet mesangial deposits were more frequently noted in patients with HBV-associated MN when compared to others with idiopathic MN. Glomerular deposits of HBsAg were not detected using indirect immunofluorescence technique. Even though HBsAg was not demonstrable within the glomeruli, HBV infection seems to play an important role in the pathogenesis of MPGN in Korean adults and MN in children.

Hepatitis B surface antigen associated nephrotic syndrome

Hepatitis B virus (HBV) has been reported in association with the nephrotic syndrome from different parts of the world, but its role as a cause of the pathological findings of nephrotic syndrome is still controversial. We report seven nephrotic children with positive hepatitis B markers in which members of their families were also positive for the markers but without clinical, renal or hepatic involvement. Four showed haematuria at onset and three developed hypertension later in the course of the disease. Only two were responsive to steroid therapy. Renal biopsy was performed in four, of whom three showed membranous nephropathy and the other showed mesangioproliferative glomerulonephritis. Four patients developed end-stage renal disease. We conclude that in our environment HBV, when detected in children with nephrotic syndrome, should not be considered as a chance finding, but may have a definite role in its pathogenesis. Moreover, the prognosis of HBV-associated nephrotic syndrome appears poor.

Ultrastructure of kidney from three patients with HBeAg-associated nephropathy with special reference to virus-like particles in the glomerular tufts

The biopsied kidneys from three patients with hepatitis Be antigen (HBeAg)-associated nephropathy were observed by light microscopy, immunohistochemistry and electron microscopy. By an indirect technique utilizing horseradish peroxidase-conjugated antisera, HBeAg was found to be deposited in a diffuse granular fashion along the glomerular capillary wall. No deposition of hepatitis Bs or hepatitis Bc antigen was detected. The three cases were diagnosed as HBeAg-associated nephropathy. Ultrastructurally, there were finely granular electron-dense deposits in the subendothelial area, basement membrane, mesangial area and subepithelial area of the glomerular tufts. In all three cases, virus-like particles between 30 and 70 nm in diameter were also found in such areas of the glomerular tufts, and rarely in the glomerular capillary lumen and space of Bowman. They occasionally formed clusters in the phagosomes of mesangial cells. In addition, tubulo-reticular structures were noted in the cytoplasm of endothelial cells in the glomerular capillaries. The presence of HBeAg both in the serum and in the kidney and of virus-like particles in the glomerular tufts suggests that HBeAg is causally related to the development of HBeAg-associated nephropathy.

Characteristics of glomerular lesions in hepatitis B virus infection

In an attempt to clarify a participation of hepatitis B virus (HBV) in the development of hepatic glomerulopathy in adults, kidney specimens obtained from 151 patients with liver diseases were studied. Although mesangial proliferation was more severe in patients with chronic hepatitis or liver cirrhosis than in those with acute hepatitis, no significant difference was observed between 82 serum hepatitis B surface antigen (HBsAg)-positive (HBV-related group) and 69 negative patients (HBV-nonrelated group). However, double contours of the glomerular capillary walls were observed more often in the former group (18/82, P less than .01), especially in the HBeAg-positive subgroup (8/24, P less than .001), than in the latter (3/69). In addition, glomerular capillary spike formation or a bubblelike appearance was observed in seven patients of the former group. Of these, all five patients examined were HBeAg-positive in their serum. By electron microscopic studies, subendothelial dense deposits and mesangial interpositions were observed more frequently in the HBV-related group, and subepithelial deposits were found only in the HBeAg-positive subgroup. The immunofluorescence study revealed IgA-dominant mesangial deposition in both HBV-related and nonrelated groups. As for the capillary wall deposits, however, IgG was dominant in 13 of the HBV-related group, but only one of the nonrelated group (P less than .01). Furthermore, one patient in the HBV-related group showed capillary wall-dominant HBeAg combined with IgG deposition.(ABSTRACT TRUNCATED AT 250 WORDS)

Improvement of proteinuria in a case of hepatitis B-associated glomerulonephritis after treatment with interferon

Disappearance of proteinuria was observed in a patient with hepatitis B-associated chronic glomerulonephritis after treatment with leukocyte interferon. The decrease of proteinuria was preceded by the disappearance of both deoxyribonucleic acid polymerase activity and hepatitis B e antigen from the patient's sera.