L’hépatite C et la santé publique

Metabolism of Direct-acting Antiviral Agents (DAAs) in Hepatitis C Therapy: A Review of the Literature

BACKGROUND

Hepatitis C virus (HCV) infection is still one of the leading causes of chronic liver disease, with chronically infected making up approximately 1% of the global population. Of those infected, 70% (55-85%) will develop chronic HCV infection. Chronic HCV infection causes substantial morbidity and mortality, with complications including cirrhosis, end-stage liver disease, hepatocellular carcinoma, and eventually death.

OBJECTIVE

Therapeutic options for chronic HCV infection have evolved dramatically since 2014, with a translation from pegylated interferon and ribavirin (associated with suboptimal cure and high treatment-related toxicity) to oral direct-acting antiviral treatment. There are four classes of direct-acting antivirals which differ by their mechanism of action and therapeutic target. They are all pointed to proteins that form the cytoplasmic viral replication complex. Multiple studies have demonstrated that direct-acting antiviral therapy is extremely well tolerated, highly efficacious, with few side effects.

METHODS

We performed an indexed MEDLINE search with keywords regarding specific direct-acting antiviral regimes and their pharmacokinetics, drug-drug interactions, and metabolism in specific settings of pregnancy, lactation, liver cirrhosis, liver transplantation and HCC risk, kidney failure and kidney transplantation.

RESULTS

We present a comprehensive overview of specific direct-acting antiviral metabolism and drug-drug interaction issues in different settings.

CONCLUSION

Despite its complex pharmacokinetics and the possibility of drug-drug interactions, direct-acting antivirals are highly efficacious in providing viral clearance, which is an obvious advantage compared to possible interactions or side effects. They should be administered cautiously in patients with other comorbidities, and with tight control of immunosuppressive therapy.

Hepatitis C Virus Infection in Pregnancy: An Update

Parenteral transmission is the major route of hepatitis C virus transmission in adults; however, vertical transmission is most common in children. There are several factors that have been shown to be associated with vertical transmission of hepatitis C virus, including hepatitis C virus RNA, human immunodeficiency virus coinfection, and peripheral blood mononuclear cell infection. As there is no effective vaccine to prevent hepatitis C virus infection, and there are no human data describing the safety of the new direct acting antiviral agents in pregnancy, the only preventive strategy for vertical transmission is to treat the hepatitis C virus infection before becoming pregnant. Direct acting antiviral agents are interferon-free, and many are also ribavirin-free. Based on animal studies, sofosbuvir plus ledipasvir may be the best safety profile during pregnancy for now; however, it is too early to recommend treating hepatitis C virus-infected pregnant women with these direct acting antiviral agents currently.

Prevalence of liver disease in veterans with bipolar disorder or schizophrenia

OBJECTIVE

To assess the prevalence of three liver diseases [hepatitis C virus (HCV), nonalcoholic fatty liver disease and alcohol-induced cirrhosis] in patients (veterans) with/without schizophrenia/schizoaffective disorder and bipolar disorder.

METHODS

A retrospective electronic chart review of Veterans Integrated Services Network 20 facilities from January 1, 2001 to December 21, 2006 selected patients to one of two groups: schizophrenia/schizoaffective disorder or bipolar disorder. Patients in both groups were compared with veterans in an equal-sized random sample from the same data set of veterans without psychiatric diagnoses. Logistic regression models evaluated risk for overall liver diseases as well as HCV, nonalcoholic fatty liver disease and alcoholic-induced cirrhosis.

RESULTS

Patients with schizophrenia (n=6521) had a higher prevalence of liver disease [22.4% versus 3.2%; odds ratio (OR)=8.73]; HCV (16.5% versus 1.9%; OR=10.21); and alcohol-related cirrhosis (1.6% versus 0.4%; OR=4.09) than matched controls. Patients with bipolar disorder (n=5319) had a higher prevalence of liver disease (21.5% versus 3.5%; OR=7.58); HCV (15.5% versus 2.1%; OR=8.60); and alcohol-related cirrhosis (1.6% versus 0.4%; OR=3.82) than matched controls. Risk factors for liver disease in patients with schizophrenia (versus matched controls) included diabetes (OR=1.29), hypertension (OR=1.27), HIV (OR=3.54), substance use disorder (SUD) (OR=2.28), alcohol use disorder (OR=3.05) and schizophrenia (OR=2.74). Risk factors for development of liver disease for patients with bipolar disorder: diabetes (OR=1.40), HIV (OR=3.66), SUD (OR=2.68), alcohol use disorder (OR=3.22) and bipolar disorder (OR=2.27).

CONCLUSIONS

This study in veterans shows that the presence of mental illness and its comorbidities represents a significant risk factor for the diagnosis of liver disease, including HCV and alcohol-related cirrhosis.

Medical consequences of drug abuse and co-occurring infections: research at the National Institute on Drug Abuse

Substance abuse still remains one of the major problems in the world today, with millions of people abusing legal and illegal drugs. In addition, a billion people may also be infected with one or more infections. Both drugs of abuse and infections are associated with enormous burden of social, economic, and health consequences. This article briefly discusses a few medical consequences of drugs of abuse and infections such as human immunodeficiency virus, hepatitis C virus, psychiatric complications in hepatitis C infection, pharmacokinetic drug-drug interactions among medications used in the treatment of addiction and infections, and new drugs in development for the treatment of infections. Research is encouraged to study interactions between infections, drugs of abuse, and underlying pathophysiologic and molecular/genetic mechanisms of these interactions.

Acute sensorineural hearing loss associated with peginterferon and ribavirin combination therapy during hepatitis C treatment: Outcome after resumption of therapy

Peginterferon and ribavirin combination therapy for the treatment of hepatitis C virus (HCV) is well known to be associated with significant adverse effects. Sensorineural hearing loss, that in most cases is unilateral, has been reported as a consequence of therapy with both non-pegylated and pegylated interferon (pegIFN) but is not a well-known adverse effect. We report a 45-year-old Caucasian woman who developed acute sensorineural hearing loss 2 mo after starting therapy with pegIFN-α 2b and ribavirin for the treatment of chronic HCV, genotype 1a. She did not report the hearing loss to the hepatitis clinic until 1 mo, later whereupon therapy was promptly discontinued. Although her serum alanine aminotransferase (ALT) normalized and her HCV-RNA became undetectable after 12 wk of pegIFN and ribavirin therapy, after discontinuation, her HCV-RNA became detectable with significant elevations of serum ALT. Four months after initial discontinuation, the patient re-commenced pegIFN and ribavirin combination therapy. After 44 of 48 wk of therapy, the patient’s liver biochemistry has normalized and the HCV-RNA is undetectable. She has not developed worsening of her hearing loss and hearing on the left-side is unaffected. Both patients and physicians should be aware that sensorineural hearing loss may occur with pegIFN therapy. Our experience suggests that re-institution of therapy is not always associated with further hearing impairment.

Human Immunodeficiency Virus, Hepatitis B, and Hepatitis C Seroprevalence in a Canadian Trauma Population

BACKGROUND

The current seroprevalence of human immunodeficiency virus (HIV), hepatitis B, and hepatitis C in the Canadian trauma population is unknown. Establishing the seroprevalence of these diseases is vital for education, postexposure prophylaxis, and counseling, and to establish potential screening guidelines. The purpose of this study was to determine the seroprevalence of HIV, hepatitis B, and hepatitis C in the trauma population of London, Ontario, Canada.

METHODS

All adult (aged > or = 18 years) trauma patients treated by the trauma team at London Health Sciences Centre were prospectively studied from January to December 2003. The study was conducted as a linked, confidential serosurvey with delayed full disclosure. Serum was analyzed for HIV, hepatitis C antibody, and Hepatitis B surface antigen.

RESULTS

A total of 287 (76%) of 377 consecutive trauma patients had blood testing completed. Of the 287 patients tested, 1 (0.3%) was positive for hepatitis B, 8 (2.8%) were positive for hepatitis C, and no patients tested positive for HIV. Hepatitis C-positive patients were predominantly men (63%) with a mean age of 46 years and a mean Injury Severity Score of 19; 63% were injured in a motor vehicle crash, and 88% were discharged alive. There were no statistically significant differences in the demographic and injury profiles from the hepatitis C-negative patients (p > 0.2 for all).

CONCLUSION

This is the first study to determine the rates of HIV, hepatitis B, and hepatitis C in the Canadian trauma population. Our trauma population demonstrated a threefold higher hepatitis C seroprevalence rate compared with the general population. Hepatitis C poses the highest risk to the trauma team of the three bloodborne diseases studied. With no vaccine or postexposure prophylaxis currently available for hepatitis C, this study highlights the importance of prevention and the strict use of universal precautions in the setting of trauma.

A comparison of disease severity and survival rates after liver transplantation in the United Kingdom, Canada, and the United States

The severity of preoperative liver disease influences the outcome of liver transplantation, is commonly used to determine priority on liver transplant waiting lists, and may differ between countries with different rates of liver disease and organ allocation systems. We compared the relative severity of liver disease in transplant recipients with chronic liver disease in the United States, Canada, and the United Kingdom and its relation to outcome. Data were obtained from national databases on patients who received transplants in the year 2000. The data included age, gender, diagnosis, the status at the time of transplantation, and indices of chronic liver disease [serum bilirubin and international normalized ratio (INR), and serum creatinine] from which a comparative score [model for end-stage liver disease (MELD) score] was calculated. The data revealed marked differences between the three countries. No patient in the United Kingdom was in intensive care before transplantation compared with 19.3% of recipients in the United States and 7.5% in Canada. The median model MELD score of recipients in the United Kingdom was 10.9 compared with 16.1 in the United States and 17 in Canada. The median MELD score of transplant recipients in North America did not vary according to diagnosis, whereas in the United Kingdom, patients with cholestatic liver disease had a lower median MELD score (8.5) than those with alcoholic liver disease (15.7) at the time of transplantation. In conclusion, the disease severity of UK liver transplant recipients varied by diagnosis and was lower than recipients in North America; the 1-year survival rate was, however, similar between the countries.