A Case of Cryoglobulinemic Membranoproliferative Glomerulonephritis Induced by Hepatitis C Virus

Efficacy of Therapeutic Apheresis for Cryoglobulinemic Vasculitis Patients with Renal Involvement: A Systematic Review

INTRODUCTION

Therapeutic apheresis (TA) is commonly used for cryoglobulinemic vasculitis (CV) patients, but its efficacy remains uncertain. This systematic review aimed to assess the efficacy of different TA modalities, such as plasma exchange (PE), plasmapheresis (PP), and cryofiltration (CF), in treating CV patients with renal involvement.

METHODS

Literature search of MEDLINE, EMBASE, and Cochrane Databases was conducted up to December 2022. Studies that reported the outcomes of TA in adult CV patients with renal involvement were assessed. The protocol for this systematic review has been registered with PROSPERO (No. CRD42023417727). The quality of each study was evaluated by the investigators using the validated methodological index for non-randomized studies (minors) quality score.

RESULTS

154 patients who encountered 170 episodes of serious events necessitating TA were evaluated across 76 studies. Among them, 51% were males, with a mean age ranging from 49 to 58 years. The CV types included 15 type I, 97 type II, and 13 type III, while the remaining patients exhibited mixed (n = 17) or undetermined CV types (n = 12). Among the treatment modalities, PE, PP, and CF were performed in 85 (56%), 52 (34%), and 17 patients (11%), respectively, with no identical protocol for TA treatment. The overall response rate for TA was 78%, with response rates of 84%, 77%, and 75% observed in type I, II, and III patients respectively. Most patients received steroids, immunosuppressants, and treatment targeting the underlying causative disease. The overall long-term renal outcome rate was 77%, with type I, II, and III patients experiencing response rates of 89%, 76%, and 90%, respectively. The renal outcomes in patients receiving PE, PP, and CF were comparable, with rates of 78%, 76%, and 81%, respectively.

CONCLUSIONS

This study presents compelling evidence that combination of TA with other treatments, especially immunosuppressive therapy, is a successful strategy for effectively managing severe renal involvement in CV patients. Among the TA modalities studied, including PE, PP, and CF, all demonstrated efficacy, with PE being the most frequently employed approach.

Immunosuppressive and antiviral treatment of hepatitis C virus-associated glomerular disease: A long-term follow-up

BACKGROUND

The evidence in the medical literature on the treatment of hepatitis C virus-associated glomerular disease is extremely limited. The advent of nonconventional immunosuppressive agents and direct-acting antivirals promises high efficacy and safety.

AIMS

We conducted an open-label, single-arm clinical study to examine the efficacy and safety of a combined approach for hepatitis C virus-associated glomerular disease.

METHODS

In the first phase of the study, patients with hepatitis C virus-associated glomerular disease received interferon-based antiviral therapy and immunosuppressive agents; since 2013, interferon-free antiviral therapy was adopted and novel immunosuppressants (including B-cell depleting agents and mycophenolate mofetil) or immunomodulators (ribavirin) were choiced. Virological and clinical responses were evaluated over a long observation period (median follow-up of 60 weeks and 46.5 months after the end of treatment with interferon and direct-acting antiviral agents, respectively).

RESULTS

We enrolled 25 consecutive patients with hepatitis C virus-associated glomerular disease, 8 being liver transplant recipients for hepatitis C. A total of 13 patients received therapy with direct-acting antivirals and experienced sustained viral response (serum hepatitis C virus RNA <12 IU/mL, 12 weeks after treatment ended, sustained viral response12). The mean (±standard deviation) proteinuria decreased from 2.61 ± 1.01 at baseline to 1.71 ± 1.43 (g/day) at sustained viral response 48, p = 0.031; microscopic hematuria and serum cryoglobulins disappeared in six (50%) and seven (64%) patients, respectively, after sustained viral response by direct-acting antivirals. Adverse events occurred in 69% (9/13) of patients and were mild, with four cases of ribavirin-related anemia requiring blood transfusions (no drop-outs). After sustained viral response by direct-acting antivirals, immunosuppressive and immunomodulatory agents were initiated in clinical relapsers ( n = 2) and nonresponders ( n = 3) with some benefit. Among patients on interferon-based regimens ( n = 12), viral response (sustained viral response 24) and dropout rates were 58% (7/12) and 33% (4/12), respectively. After sustained viral response by interferon-based therapy, clinical relapsers ( n = 3) were successfully managed with immunosuppressive agents in two patients.

CONCLUSION

Treatment with direct-acting antivirals provides excellent rates of viral response and safety in patients with hepatitis C virus-related glomerular disease; viral response was frequently accompanied by clinical improvement. The absence of hepatitis C virus RNA from serum allowed immunosuppressive and immunomodulatory therapies with benefits for glomerular abnormalities and no concern on hepatitis C virus replication.