Role of interferon-alpha in the treatment of primary glomerulonephritis

Hepatitis B-related glomerulonephritis and optimization of treatment

Introduction: Multiple studies have revealed a strong relationship between the development of nephropathy and hepatitis B virus (HBV) infection. The underlying pathogenesis of hepatitis B-related glomerulonephritis (HBV-GN) involves immune complexes, which can be isolated from kidney tissues. Clearance of HBV antigenemia improves renal impairment and proteinuria in HBV-GN patients.Areas covered: In this review, we present our current understanding of the epidemiology, pathogenesis, pathology, diagnosis, and treatment of HBV-GN. We discuss the advantages and disadvantages of oral nucleoside/nucleotide analogs (NAs), and the main pharmaceutical treatment for hepatis B.Expert opinion: Currently, antiviral agents are the main HBV-GN therapeutic agents. Although no randomized controlled clinical trials have compared the efficacy of interferon (IFN) and NA, we suggest IFN treatment for pediatric patients (IFN-α in patients ≥1 year; pegIFN-α in patients ≥3 years) considering treatment duration and absence of resistance. Novel NAs have brought about promising treatment options involving high efficacy viral suppression and low resistance rates. NAs with a high barrier to resistance (e.g. entecavir) are recommended as first-line therapy of HBV-GN. Immunosuppression monotherapy, such as corticosteroids, is of little benefit and potentially harmful to HBV-GN patients due to the possibility of viral reactivation.

Interferon Therapy for HCV-Associated Glomerulonephritis: Meta-Analysis of Controlled Trials

Background

A relationship between hepatitis C virus (HCV) infection and chronic glomerulonephritis (GN) has been asserted on the grounds of epidemiological and experimental data. Although this suggests a role for an antiviral approach to HCV-associated GN instead of the more conventional immunosuppressive (or supportive) therapy, the optimal management of HCV-related glomerulonephritis remains controversial.

Objective

To compare antiviral with immunosuppressive therapy for HCV-associated GN.

Design

Meta-analysis of controlled clinical trials (CCTs) of the two treatments (antiviral versus immunosuppressive) of HCV-associated GN.

Methods

We used the fixed or random effects model of DerSimonian and Laird, with heterogeneity and sensitivity analyses. The rate of proteinuria and serum creatinine decrease after therapy for HCV-associated GN were regarded as the most reliable outcome end-points.

Results

We identified six studies involving 145 unique patients with HCV-associated GN. Pooling of study results demonstrated that proteinuria decreased more commonly after IFN than corticosteroid therapy (OR 1.92 (95% CI, 0.39; 9.57), NS), P-test for heterogeneity, 0.06 (I2=52.9%). In a sensitivity analysis including only CCTs using standard IFN-doses, OR was 3.86 (95% CI, 1.44; 10.33, (P=0.007)), P-test for heterogeneity, 0.18 (I2=35.9%). No improvement of serum creatinine after IFN compared to immunosuppressive therapy was noted (OR, 0.59 (95% CI, 0.21; 1.65), NS), P-test for heterogeneity, 0.76 (I2=0%). Only three CCTs gave information on the rate of proteinuria decrease over follow-up (OR, 5.08 (95% CI, 0.69; 37.31), NS). A few major side effects were noted after IFN administration.

Conclusions

Our meta-analysis indicates that standard IFN-doses were more effective than immunosuppressive therapy in lowering proteinuria of patients with HCV-related glomerulonephritis. However, no significant improvement in serum creatinine was seen by IFN or steroid therapy across the studies. Also, information on proteinuria recurrence after the completion of antiviral therapy was not sufficient. Prospective, randomized trials based on combined antiviral therapy (pegylated IFN plus ribavirin) with adequate dose and follow-up are required to assess the efficacy and safety of antiviral treatment of HCV-associated glomerulonephritis.

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.

Antiviral therapy for HCV-associated cryoglobulinemic glomerulonephritis: case report and review of the literature

We describe the case of a 51-year-old woman with HCV-associated cryoglobulinemic glomerulonephritis (GN). She presented mild deterioration of kidney function, non-nephrotic proteinuria, and active urinary sediment. Kidney biopsy showed features of membranoproliferative changes with some sclerosis. Sustained viral response (SVR) was obtained by 6 months of antiviral therapy (peg-IFN-α2a plus ribavirin). SVR was linked with improvement of kidney function and remission of proteinuria. Clinical and virological remission persists over a 25-month follow-up. This case report emphasizes efficacy and safety of antiviral treatment of HCV-associated glomerulonephritis--preliminary but encouraging results exist. We identified by systematic review of the literature 9 studies (156 unique patients); the pooled estimate of frequency of sustained virological response after IFN-based therapy was 0.49 (95% confidence interval, CI: 0.21, 0.77; p < 0.0005; random effects model). Heterogeneity was found (I(2) = 98.9%, p < 0.0001). Two possible regimens should be considered for the treatment of HCV-associated cryoglobulinemic GN according to the clinical presentation. Immunosuppressive therapy is recommended for HCV-related kidney disease having aggressive course, and recent evidence supports rituximab (RTX) use with a reduced exposure to corticosteroids. We identified six studies (66 unique patients) on RTX therapy for HCV-associated kidney disease; at the end of RTX therapy, the pooled estimate of the mean decrease in proteinuria was 1.4 g/24 h (95% CI: 0.75, 2.05, p < 0.001); The p test for heterogeneity gave a value of 0.94 (I(2) = 0). Several questions related to RTX use remain. HCV-induced GN is uncommon among CKD patients of developed countries, and this clearly hampers prospective controlled clinical trials aimed to evaluate efficacy and safety of antiviral or immunosuppressive therapy in this population.

Hepatitis B virus related membranous glomerulonephritis and proteinuria treated with lamivudine and tenofovir

Membranous glomerulonephritis is the most common histological renal lesion associated with hepatitis B virus (HBV) infection. The authors describe here a case of a patient presenting with the nephrotic syndrome and HBV infection but without progressive liver disease. The use of lamivudine and tenofovir resulted in arrest of proteinuria and stabilisation of renal function.

Membranous nephropathy associated with chronic hepatitis B occurring in a short period after acute hepatitis B virus infection

We herein present a case of membranous nephropathy associated with chronic hepatitis B following acute hepatitis B virus (HBV) infection. A 22-year-old man was admitted to our hospital for evaluation of proteinuria, pitting edema on both legs, and increased body weight in December 2002. At the age of 18, he had suffered from acute hepatitis A and syphilis, and was found to be negative for hepatitis B surface antigen (HBsAg). Furthermore, he suffered from acute hepatitis B (AH-B) at the age of 21; he was found to be positive for HBsAg and anti-IgM antibody to core antigen (IgM HBcAb). However, he discontinued outpatient treatment before confirmation of HBsAg clearance or the appearance of antibody to HBsAg (HBsAb). At the present admission, HBsAg, antibody to hepatitis B e antigen (HBeAg), and HBcAb were positive, while IgM HBcAb was negative. His genotype of HBV was type A (HBV/A). Histopathological findings of the renal biopsy specimen confirmed glomerulonephritis and glomerular deposition of HBsAg. Thus, he was diagnosed as having nephrotic syndrome caused by membranous nephropathy (MN) associated with chronic hepatitis B (CH-B) following AH-B. Although interferon-alpha (IFN-alpha) administration was started for the treatment and temporary improvement of proteinuria was observed, remission of MN was not achieved.

Interferon-beta reduces proteinuria in experimental glomerulonephritis

Interferon-beta (IFN-beta) is a multifunctional cytokine with immunomodulatory properties. We examined the effect of IFN-beta in three separate rat models of glomerular injury and in cultured human glomerular endothelial cells and podocytes. In nephrotoxic nephritis in WKY rats, recombinant rat IFN-beta started either at induction or after establishment of disease significantly reduced 24-h proteinuria by up to 73% and 51%, respectively, but did not affect serum creatinine. There was a slight reduction in numbers of glomerular macrophages, but no difference in glomerular or tubulointerstitial scarring. In Thy-1 nephritis in Lewis rats, IFN-beta started at induction of disease reduced proteinuria by up to 66% with no effect on numbers of glomerular macrophages, but a reduced number of proliferating cells. In puromycin nephropathy in Wistar rats, IFN-beta started at induction of disease reduced proteinuria by up to 93%, but had no effect on glomerular histology. In cultured cells, human IFN-beta-1a had a dramatic effect on barrier properties, increasing electrical resistance across monolayers of either glomerular endothelial cells or podocytes and decreasing trans-monolayer passage of albumin. In conclusion, these results show that IFN-beta reduces proteinuria in three different rat models of glomerular injury and that its anti-proteinuric action may result from direct effects on cells that comprise the glomerular filtration barrier. These data indicate that IFN-beta may have potential as a therapeutic agent in proteinuric renal disease.