Hepatitis C virus genotypes in patients on renal replacement therapy

Viral hepatitis C in Hong Kong

OBJECTIVE

Hepatitis C virus (HCV) infection can lead to serious liver disease. Its medico-socio-economic burden on society can be immense. This study investigates the epidemiology of HCV infection in Hong Kong.

METHODS

Data from the Department of Health, relevant publications from Medline search and data from two acute hospitals were reviewed.

RESULTS

The prevalence of anti-HCV among voluntary blood donors is stable, remaining at approximately 0.035-0.099% over the past 10 years, and is higher in the older age group. Among the high-risk groups, the anti-HCV prevalence is as follows: (1) hospital patients 0.8%, (2) intravenous drug users 46.0%, (3) patients infected with HIV 7.9%, (4) children with transfusion-dependent hematologic disease 16.3%, (5) patients on continuous ambulatory peritoneal dialysis 1.8%, patients on hemodialysis 16.4%, recipients of kidney transplants 6.2% and (6) patients with hepatocellular carcinoma 7.3%. Among blood donors, 58.8% were infected with HCV genotype 1b and 27.0% with genotype 6a. Genotype 6a is particularly common among intravenous drug users.

CONCLUSION

Hong Kong has a low prevalence of HCV infection. Patients are mostly infected through transfusion with blood or products prior to the introduction of anti-HCV screening to the blood transfusion service. Illicit drug use constitutes another significant risk. Since 1997, there has been a great increase in population movement between China and Hong Kong which might affect the epidemiology of HCV infection.

[Prevalence of hepatitis C, hepatitis B and HIV infection among haemodialysis patients in Ibn-Rochd university hospital, Casablanca]

The viral infections are frequent in haemodialysis patients, notably those due to the hepatitis C virus (HCV), the hepatitis B virus (HBV) and the human immunodeficiency virus (HIV). The objective of this study is to determine the prevalence of the hepatitis C, the hepatitis B, the HIV infection in haemodialysis patients and the main risk factors for hepatitis C in the chronic haemodialysis patients treated in haemodialysis unit of Ibn Rochd University Hospital in Casablanca. This retrospective study was performed in 186 chronic haemodialysis patients and showed a high prevalence of HVC infection (76%), the prevalence of HBV infection was at 2%, none of the patients had detectable antibodies of HIV. Among the patients infected by the HCV, the mean duration of dialysis was 8,7 years. The mean number of blood units transfused was 16,5. Seventeen patients (11%) had no history of blood transfusion. In conclusion, the blood transfusion is not considered to be a like a major risk factor of the HCV infection in haemodialysis patients and this since the systematic detection of the anti-HCV antibodies in the blood donors. The nosocomial transmission of HCV seems to be the main risk factor HCV infection in the haemodialysis units requiring a strict adherence to infection control procedures for prevention of HVC infection in haemodialysis patients.

Hepatitis C virus genotype distribution in China: predominance of closely related subtype 1b isolates and existence of new genotype 6 variants

To determine hepatitis C virus (HCV) genotype distribution in China, a total of 148 HCV RNA positive serum samples were collected from nine geographic areas and subjected to RT-PCR followed by direct DNA sequencing and phylogenetic analysis of the core, E1, and NS5B regions. HCV was genotyped in 139 (93.9%) samples. Among them subtype 1b was the most predominant [66% (92/139)] followed by 2a [14% (19/139)]. Of 92 subtype 1b isolates, 35 (38%) and 30 (33%) formed two clusters, designated groups A and B. Group A was prevalent throughout China, while group B was predominant in the central and southern regions. In three cities in the Pearl River Delta, subtype 6a replaced 2a as the second most predominant subtype, and in Kunming (southwest) multiple HCV genotypes/subtypes were present. New variants of HCV genotype 6 were discovered in three samples from Kunming and one in Guangzhou in the Pearl River Delta.

Successful treatment of hepatitis C after kidney transplantation with combined interferon alpha-2b and ribavirin

The management of acute hepatitis C virus (HCV) infection after renal transplantation (RT) remains controversial, due to the potential risk of interferon-induced graft dysfunction. There is little experience with combined interferon and ribavirin therapy in this group of patients. We treated four consenting RT recipients who developed acute de novo HCV infection with a combination of interferon-alpha 2b and ribavirin. After 48 weeks' treatment, sustained virologic and biochemical remission were achieved in three patients infected with HCV genotypes 1a, 2, and 6a, respectively. The median time from treatment onset to ALT normalization was 8 weeks. The fourth patient was a non-responder infected with genotype 1b. Dose-dependent hemolysis was the most frequent side-effect. No patient developed allograft dysfunction. Our experience indicates that the judicious use of combined interferon and ribavirin can be considered in selected RT recipients with severe acute hepatitis C infection.

Unexpected distribution of hepatitis C virus genotypes in patients on hemodialysis and kidney transplant recipients

The distribution of hepatitis C virus (HCV) genotypes in patients on hemodialysis and in kidney transplant recipients was compared with that observed in a control group composed of HCV-infected individuals from the general population. A total of 340 patients were included in the study: 46 with end-stage renal disease on regular hemodialysis treatment, 22 kidney transplant recipients and 272 controls matched for sex and age at a 4:1 ratio (controls to patient). HCV genotype was determined by sequencing of the 5' untranslated region of the HCV genome. No difference was observed in the distribution of HCV genotypes in hemodialysis patients and renal transplant patients (P = 0.47). However, when each of these groups was compared with the control group, a significant difference was detected in the genotype distribution (P < 0.001). In hemodialysis and renal transplant patients the most prevalent subtype was 1a, followed by 1b, 3, and other less prevalent genotypes (2, 4, and 5), whereas in the control group the most prevalent subtype was 1b, followed by 3, 1a, and others. That observation may reflect differences in the epidemiology of HCV infection, viral characteristics and host factors in renal patients in comparison to the control group.

Significance of immune status, genotype and viral load in the severity of chronic hepatitis C in HIV infected haemophilia patients

Chronic hepatitis C is associated with more severe liver disease in patients coinfected with HIV, but the pathogenic mechanism of this more aggressive course is still unclear. The aim of this study was to assess the relationship of HCV genotype, viral load and epidemiological factors with the histological severity of chronic hepatitis in haemophilia patients with HCV/HIV coinfection, taking into consideration the immune status of the patients. Twenty-one HIV/HCV coinfected haemophilia patients, with mean age +/- SD 35.7 +/- 8.7 years, underwent transcutaneous liver biopsy 6-15 years (median 12 years) after HIV and 6-32 (median 21.5 years) years after HCV infection. Twelve patients were stage A (CDC), six stage B and three stage C. CD4 cells were < 50 microL(-1) in three patients (14.3%), 50-200 in 11(52.4%) and > 200 in 7(33.3%). Mean +/- SD log(10) HCV-RNA was 6.87 +/- 0.7 copies mL(-1) (range 5.4-7.9), and mean +/- SD log(10) HIV-RNA was 3.75 +/- 0.98 copies mL(-1) (range 2.7-6), at the time of liver biopsy. Minimal hepatitis was diagnosed in five patients (24%), mild in 10 (48%) and moderate in six (28%). Hepatitis stage 0-2 was found in seven cases (33%) and cirrhosis in six (29%). Statistical analysis showed a significant association of CD4 count < 50 with minimal hepatitis and of CD > 200 with mild and moderate hepatitis (P = 0.033). In addition, minimal hepatitis was found only in patients with stage C, while the majority of subjects with HIV stage A showed mild and moderate hepatitis (P = 0.003). Moreover genotype 1 was independently associated with advanced hepatitis stage (P = 0.04). No relationship was found between hepatitis severity, HIV or HCV RNA levels, patient's age and duration of HIV or HCV infection. Our results suggest that HCV/HIV coinfection may aggravate the course of hepatitis in the phase of immunocompetence, most probably through an immune mediated process. Genotype 1 seems to be associated with advanced liver disease.