Hepatitis C Virus-associated Membranoproliferative Glomerulonephritis Treated with Directly Acting Antiviral Therapy

Hepatitis C-Induced Immunoglobulin A (IgA) Nephropathy: An Uncommon Cause of Hematuria

Immunoglobulin (Ig)A nephropathy, also known as Berger's disease, is characterized by IgA deposits in the kidney's mesangium and can lead to serious outcomes, including rapidly progressive glomerulonephritis. While Hepatitis C virus (HCV) infection is commonly associated with liver involvement, it is also linked to various renal pathologies, including membranous nephropathy and membranoproliferative glomerulonephritis. However, IgA nephropathy secondary to HCV is rare. This case study involves a 24-year-old male with a known history of untreated Hepatitis C, who presented with hematuria and foamy urine. Laboratory findings revealed increased levels of serum creatinine and urea, significant proteinuria, and a high HCV RNA viral load. A renal biopsy confirmed the diagnosis of IgA nephropathy with strong IgA and C3 deposits observed on immunofluorescence. Treatment with angiotensin receptor blockers and antiviral therapy led to substantial symptomatic improvement and stabilization of renal function. This case underscores the critical importance of considering IgA nephropathy in the differential diagnosis of renal complications in HCV-infected patients. Early detection and treatment of Hepatitis C are vital, as timely intervention can markedly enhance patient outcomes and mitigate the risk of serious complications. A heightened awareness of the potential renal implications of HCV emphasizes the urgency of proactive monitoring and swift management to safeguard kidney function and overall health.

Seroprevalence of hepatitis C virus in Jinan, China, 2008-2020

BACKGROUND

The updated estimates of hepatitis C virus (HCV) seroprevalence are critical for developing strategies to manage or eliminate HCV infection.

METHODS

A comprehensive study on HCV seroprevalence was conducted among 365,210 patients at Jinan Central Hospital, China, from 2008 to 2020. The patients were tested for anti-HCV, HCV core antigen, hepatitis B surface antigen, syphilis antibody, human immunodeficiency virus antigen + antibody, antihepatitis A virus IgM, and antihepatitis E virus IgM.

RESULTS

HCV seroprevalence was 0.79% and was related to age. HCV seropositivity was lower in children (aged  < 18 years) than in adults (aged  ≥ 18 years) (0.15% vs. 0.81%). High HCV prevalence was reported in adults aged  ≥ 41 years, and HCV seropositivity in those aged 41-80 years accounted for 74.56% of all seropositive individuals. Notably, the rate of HCV-HIV coinfection was 0. HCV seroprevalence was considerably higher in patients at the Kidney Disease Unit and Dialysis Department than in those at other departments (inpatient or outpatient).

CONCLUSIONS

HCV seroprevalence was lower in Jinan region but higher in patients at the Kidney Disease Unit and Dialysis Department, especially in those undergoing hemodialysis.

Immune disorders and rheumatologic manifestations of viral hepatitis

Infection with hepatotropic viruses is not limited to the liver and can lead to the development of various immunological disorders (the formation of cryoglobulins, rheumatoid factor, antinuclear antibodies, autoantibodies specific for autoimmune hepatitis and primary biliary cholangitis, and others), which can manifest as glomerulonephritis, arthritis, uveitis, vasculitis (cryoglobulinemic vasculitis, polyarteritis nodosa, Henoch-Schonlein purpura, isolated cutaneous necrotizing vasculitis), and other rheumatologic disorders, and be a trigger for the subsequent development of autoimmune hepatitis and primary biliary cholangitis. A further study of the association between autoimmune liver diseases and hepatotropic virus infection would be useful to assess the results of treatment of these associated diseases with antiviral drugs. The relationship of these immune disorders and their manifestations with hepatotropic viruses is best studied for chronic hepatitis B and C. Only isolated cases of these associations are described for hepatitis A. These links are least studied, and are often controversial for hepatitis E, possibly due to their relatively rare diagnoses. Patients with uveitis, glomerulonephritis, arthritis, vasculitis, autoimmune liver diseases should be tested for biomarkers of viral hepatitis, and if present, these patients should be treated with antiviral drugs.

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.