Rituximab therapy for primary glomerulonephritis: Report on two cases

Therapies for Membranous Nephropathy: A Tale From the Old and New Millennia

Primary Membranous Nephropathy (PMN) is the most frequent cause of nephrotic syndrome in adults. If untreated, PMN can lead to end-stage renal disease; moreover, affected patients are at increased risk of complications typical of nephrotic syndrome such as fluid overload, deep vein thrombosis and infection. The association of PMN with HLA-DQA1 and the identification in around 70% of cases of circulating autoantibodies, mainly directed towards the phospholipase A2 receptor, supports the autoimmune nature of the disease. In patients not achieving spontaneous remission or in the ones with deteriorating kidney function and severe nephrotic syndrome, immunosuppression is required to increase the chances of achieving remission. The aim of this review is to discuss the evidence base for the different immunosuppressive regimens used for PMN in studies published so far; the manuscript also includes a section where the authors propose, based upon current evidence, their recommendations regarding immunosuppression in the disease, while highlighting the still significant knowledge gaps and uncertainties.

Ribavirin as a beneficial treatment option for hepatitis C virusassociated glomerular disease

The management of hepatitis C virus (HCV)-induced glomerular disease remains unsatisfactory despite novel advances in antiviral and immunosuppressive therapy. Recent evidence highlighted the role of ribavirin, a drug provided with immunomodulatory properties, in the treatment of glomerular diseases associated with chronic HCV. We administered low-dose ribavirin (200 mg/day or 200 mg twice a week or 200 mg thrice weekly) in a prospective fashion to a group of patients with HCV-associated glomerular disease (n = 7). Ribavirin monotherapy was given in most (n = 6) patients and was accompanied by erythropoietin therapy in all. The primary endpoint was reduction of 24-h proteinuria after treatment ended; the secondary end-points were decrease in serum creatinine and amelioration of urinary abnormalities. We collected data on on-treatment adverse events (AEs), serious AEs, and laboratory abnormalities. Many patients (n = 6) had inactive HCV infection as they had shown HCV RNA clearance from serum after antiviral therapy with direct-acting antivirals. Some patients (n = 4) had membranoproliferative glomerulo- nephritis, the diagnosis being confirmed by kidney histology in three cases; others (n = 2) received diagnosis of diabetic glomerulosclerosis, confirmed in one by kidney biopsy. We observed consistent reduction of 24-h proteinuria in two individuals after ribavirin therapy; another patient reported disappearance of microscopic hematuria. We found severe AE (hemolytic anemia) in three patients which required discontinuation of ribavirin treatment in two patients, one required hospitalization. Other AEs were cutaneous rash (n = 1), dyspepsia (n = 1), and fatigue (n = 1). Low-dose ribavirin was able to give consistent reduction of 24-h proteinuria in two patients; tolerance to ribavirin was unsatisfactory. We need further studies aimed to expand our knowledge on ribavirin therapy of HCV-associated glomerular disease. The low incidence of the disease hampers the conduction of clinical trials on this aim.

Direct-Acting Antiviral Agents for HCV-Associated Glomerular Disease and the Current Evidence

Glomerular disease is an extra-hepatic manifestation of hepatitis C virus infection (HCV) and membranoproliferative glomerulonephritis is the most frequent glomerular disease associated with HCV. It occurs commonly in patients with HCV-related mixed cryoglobulinemia syndrome. Patients with HCV-related glomerular disease have been historically a difficult-to-treat group. The therapeutic armamentarium for HCV-related glomerular disease now includes antiviral regimens, selective or non-specific immunosuppressive drugs, immunomodulators, and symptomatic agents. The treatment of HCV-associated glomerular disease is dependent on the clinical presentation of the patient. The recent introduction of all-oral, interferon (IFN)-free/ribavirin (RBV)-free regimens is dramatically changing the course of HCV in the general population, and some regimens have been approved for HCV even in patients with advanced chronic kidney disease. According to a systematic review of the medical literature, the evidence concerning the efficacy/safety of direct-acting antiviral agents (DAAs) of HCV-induced glomerular disease is limited. The frequency of sustained virological response was 92.5% (62/67). Full or partial clinical remission was demonstrated in many patients (n = 46, 68.5%) after DAAs. There were no reports of deterioration of kidney function in patients on DAAs. Many patients (n = 29, 43%) underwent immunosuppression while on DAAs. A few cases of new onset or relapsing glomerular disease in patients with HCV successfully treated with DAAs have been observed. In summary, DAA-based combinations are making easier the management of HCV. However, patients with HCV-induced glomerular disease are still a difficult-to-treat group even at the time of DAAs.

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.

Managing refractory cryoglobulinemic vasculitis: challenges and solutions

Cryoglobulinemia is thought to be a rare condition. It may be an isolated disorder or secondary to a particular disease. According to immunoglobulin composition, cryoglobulinemia is classified into three types. In mixed cryoglobulinemia (types II and III), vascular deposition of cryoglobulin-containing immune complexes and complement may induce a clinical syndrome, characterized by systemic vasculitis and inflammation – cryoglobulinemic vasculitis (CryoVas). Most common clinical manifestations in CryoVas are skin lesions (orthostatic purpura and ulcers), weakness, peripheral neuropathy, Raynaud’s phenomenon, sicca syndrome, membranoproliferative glomerulonephritis, and arthralgia and seldom arthritis. In patients with mixed cryoglobulinemia, prevalence of anti-hepatitis C virus (HCV) antibodies and/or HCV RNA, detected by polymerase chain reaction (PCR), is reported to be up to 90%, indicating a significant role of HCV in the development of this condition. The goals of therapy for mixed cryoglobulinemia include immunoglobulin level reduction and antigen elimination. CryoVas not associated with HCV infection should be treated according to treatment recommendations for small-vessel vasculitides. CryoVas associated with chronic HCV infection should be treated with antivirals along with immunosuppressive drugs, with or without plasmapheresis, depending on disease severity and organ involvement. Patients who do not respond to first-line therapy may achieve remission when treatment with rituximab is started as second-line therapy. In HCV-related CryoVas, antiviral therapy should be given along with rituximab in order to achieve complete or partial remission. Moreover, rituximab has proven to be a glucocorticoid-sparing medication. Other potential therapies for refractory CryoVas include mycophenolate mofetil and belimumab, while tumor necrosis factor (TNF) inhibitors are not effective.