Interferon as treatment for acute hepatitis C. A meta-analysis

[Current status of acute hepatitis C]

Acute hepatitis C (AHC) is an increasing health issue. Despite the decline of blood-to-blood transmission of hepatitis C virus (HCV) through donor screening programs and a decline in intravenous drug use, the incidence of sexual transmission has now increased, particularly in HIV-infected homosexual patients. The presentation is almost always asymptomatic, which complicates diagnosis. Spontaneous clearance of the virus occurs in 25% of cases and usually, within the first three months after onset of symptoms and in symptomatic patients. If serum HCV-RNA remains detectable after this period, antiviral treatment should be started without delay, since sustained viral response rate in the acute phase is higher than that achieved with chronic liver disease. The optimal treatment regimen (interferon alone or combined with ribavirin) and its duration are not clearly established at the present time.

Acute hepatitis C: current status and remaining challenges

The acute phase of hepatitis C virus (HCV) infection represents a key point in the evolution of hepatitis C. In some patients, the infection resolves spontaneously, whereas in others it develops into chronic disease. However, because acute hepatitis C is often asymptomatic, detection and diagnosis are usually difficult. What is more, there are no established treatment guidelines, leaving physicians to make several challenging decisions, such as whether to treat, when to treat and what treatment regimen to use. Pegylated interferon alfa monotherapy is most commonly used to treat patients with acute hepatitis C; the role of ribavirin has yet to be established. In this review, we discuss the epidemiology of acute hepatitis C, its risk factors and routes of transmission and current treatment practices. We also discuss data from published clinical studies and focus on unresolved issues for which additional studies are needed in order to establish standardized treatment guidelines for the management of acute hepatitis C.

Randomisation to protect against selection bias in healthcare trials

BACKGROUND

Randomised trials use the play of chance to assign participants to comparison groups. The unpredictability of the process, if not subverted, should prevent systematic differences between comparison groups (selection bias), provided that a sufficient number of people are randomised.

OBJECTIVES

To assess the effects of randomisation and concealment of allocation on the results of healthcare trials.

SEARCH STRATEGY

We searched the Cochrane Methodology Register, MEDLINE, SciSearch, reference lists up to August 2000 and used personal communication.

SELECTION CRITERIA

Cohorts of trials, systematic reviews or meta-analyses of healthcare interventions that compared outcomes or prognostic factors for one of the following comparisons: randomised versus non-randomised trials, randomised trials with adequately versus inadequately concealed allocation, or high versus low quality trials where selection bias could not be separated from other sources of bias.

DATA COLLECTION AND ANALYSIS

One of us went through all of the citations in the Cochrane Methodology Register and accumulated reference lists. Studies that appeared to meet the inclusion criteria were retrieved and assessed independently by two of the reviewers. The methodological quality of included studies was appraised and information extracted by one of us and checked by a second. Tabular summaries of the results were prepared for each comparison and the results across studies were assessed qualitatively to identify common trends or discrepancies.

MAIN RESULTS

We identified 32 studies including over 3000 trials. Twenty-two studies compared randomised versus non-randomised trials, three compared adequately versus inadequately concealed allocation, and nine compared high versus low quality trials (some studies included more than one comparison). Five studies were of high methodological quality. In 15 of the 22 studies that compared randomised and non-randomised trials of the same intervention, important differences were found in the estimates of effect. Some of these differences were due to a poorer prognosis in the control groups in the non-randomised trials. The results of the other seven studies that compared randomised and non-randomised trials across different interventions are less clear. Comparisons of adequately and inadequately concealed allocation in randomised trials of the same intervention provided high quality evidence that concealment can be crucial in achieving similar treatment groups and, therefore, unbiased estimates of treatment effects. Studies with inadequate concealment tended to overestimate treatment effects. Comparisons of high and low quality trials of the same intervention have found important differences in estimates of effect, but it is not possible to determine the extent to which these differences can be attributed to randomisation or concealment of allocation. Omitting comparisons between randomised trials and non-randomised trials using historical controls did not substantially alter the results or conclusions of our review.

AUTHORS' CONCLUSIONS

On average, non-randomised trials and randomised trials with inadequate concealment of allocation tend to result in larger estimates of effect than randomised trials with adequately concealed allocation. However, it is not generally possible to predict the magnitude, or even the direction, of possible selection biases and consequent distortions of treatment effects.

Treatment of anicteric acute hepatitis C with peginterferon alpha-2a plus ribavirin

BACKGROUND

Hepatitis C virus (HCV) infection is the most frequent cause of chronic hepatitis, cirrhosis, and hepatocellular carcinoma in the world. Acute hepatitis C is the most commonly asymptomatic liver disease with the development of chronic HCV infection in the majority of infected patients. Studies of the natural history of HCV infection suggest that only 15-30% of patients with acute infection recover spontaneously. Others, up to 85% of the infected patients develop chronic hepatitis C. Acute hepatitis C is so uncommon and with the unpredictable occurrence, and of the low frequency, that it is difficult to determine the optimal treatment of this disease. There have been many randomized, controlled trials of the therapy in patients with chronic hepatitis C, but none of an adequate size or rigor in patients with acute hepatitis C. Therefore, the causal treatment of patients with acute hepatitis C aimed at the prevention of chronic liver disease is necessary.

CASE REPORT

We have treated a patient with anicteric form of acute hepatitis C after a three-month outpatient follow-up using a combined therapy: pegylated interferon-alpha 2a, 180 microg, subcutaneously, once a week plus ribavirin 1000 mg orally once a day. The treatment lasted 24 weeks. Stable biochemical and virological response was achieved both at the end of the treatment and 6 months after the completion of the therapy.

CONCLUSION

We believe that the above mentioned might be one of the approaches to the treatment of acute hepatitis C. However, further prospective studies with significantly larger number of patients are necessary for the definite conclusions about the treatment of HCV infections.

Challenges and Controversies in the Management of Hepatitis C Virus Infection (Part 1)

Hepatitis C virus (HCV) is emerging as a public health issue in most counties worldwide. The prevalence of HCV infection varies among different geographical areas from 0.5% to 40% with an overall global prevalence of 3%. The WHO estimates that around 170 million people are chronically infected with HCV world wide. Hepatitis CV infection causes a slowly progressive liver disease in over 60% of infected individuals culminating into cirrhosis and ultimately leading to liver failure and hepatocellular carcinoma (HCC). Chronic liver disease due to HCV infection is now the leading indication for livertransplantation both in Europe and the USA. Although the incidence of acute hepatitis C has decreased over the last decade, the number of individuals with HCV-related liver disease continues to rise and is projected to peak around year 2015. As such HCV infection imposes a significant burden on the already exhausted health resources, particularly in the developing counties where the infection is endemic and its incidence is increasing.

[Therapy of acute hepatitis C infection]

BACKGROUND

Hepatitis C viral infection is a major cause of chronic hepatitis, liver cirrhosis and hepatocellular carcinoma. The progression of acute to chronic infection occurs in 50-90% of cases. There is no standard therapy for acute HCV infection. Comparative studies are required to verify the optimal doses, dosage schedules and the treatment duration, and to establish the optimal treatment for acute hepatitis C. Recent reports have demonstrated that early application of interferon alpha was a treatment of choice for acute HCV infection. The addition of ribavirinin in the treatment of acute HCV infection, and HCV genotype, did not improve the end-of-treatment responses. It is important to consider the treatment of acute HCV infection before it progresses to chronic state.

CASE REPORT

Beneficial effect of interferon therapy in a patient with acute hepatitis C is presented. Early treatment with 3 MIU interferon alpha, three times a week, within six-months, resulted in the normal serum aminotransferases, and good virological response in our patient.

CONCLUSION

Interferon therapy significantly increased the probability of obtaining normal serum aminotransferases and undetectable HCV RNA, following acute HCV infection.

Natural interferon alpha treatment and interferon alpha receptor 2 levels in acute hepatitis C

Efficacy of interferon (IFN) therapy during the acute phase of hepatitis C infection is promising, although the optimal regimen has yet to be determined. It is not known whether the known prognostic factors for chronic hepatitis C (CHC) influence the effect of IFN in acute hepatitis C (AHC). Seventeen patients with AHC were analyzed for hepatic IFN alpha receptor 2 (IFNAR2) prior to IFN treatment. All patients were subsequently treated with either 168 million units (MU) or 336 MU of natural IFN alpha. Seventeen age-matched samples of CHC were provided as controls. The overall sustained response rate was 64.7% (11/17). In patients who received a total dose of 168 MU IFN, the sustained response rate was 28.6% (2/7), and in those who received 336 MU of IFN, the sustained response rate was 90.0% (9/10). The peaks of ALT and HCV-RNA quantity were not associated with the response to IFN. The hepatic IFNAR2 levels were 1.52 +/- 0.34 densitometry units and 0.92 +/- 0.16 in AHC and CHC, respectively (P = 0.042). There was no difference in hepatic IFNAR2 levels between sustained virological responders (SVR) and nonsustained virological responders (NR). The hepatic receptor levels were higher in AHC than in CHC patients. The levels of hepatic IFNAR2 did not differ in SVR and NR, indicating that high-dose natural IFN alpha treatment is effective for AHC, irrespective of the levels of hepatic IFNAR2.

When and how to treat acute hepatitis C?

BACKGROUND

Appropriate treatment of acute hepatitis C is still a matter of controversy due to the lack of large controlled trials.

AIM

To assess the effectiveness of interferon as treatment for acute hepatitis C by meta-analysis.

METHODS

MEDLINE search (1985-2002) was supplemented with manual searches of reference lists. Studies were included if they were controlled trials comparing interferon to no treatment and if they included patients with either post-transfusion or sporadic acute hepatitis C. Twelve trials were analyzed (414 patients). The outcome assessed was the sustained virological response (SVR) rate (undetectable hepatitis C virus RNA in serum at least 6 months after cessation of therapy).

RESULTS

Interferon significantly increased the SVR (risk difference 49%; 95% confidence interval 32.9-65%) in comparison to no treatment. The risk difference of SVR increased from 5 to 90% when trials were ordered by increasing interferon weekly dose. Delaying therapy by 8-12 weeks after the onset of disease does not compromise the SVR rate.

CONCLUSIONS

Current evidence is sufficient to recommend interferon treatment of patients with acute hepatitis C. A later initiation of therapy yields the same likelihood of response as early treatment. A daily induction dose during the 1st month is the best option of treatment.

Acute hepatitis C: high rate of both spontaneous and treatment-induced viral clearance

BACKGROUND & AIMS

Acute hepatitis C virus infection accounts for approximately 20% of cases of acute hepatitis today. The aim of this study was to define the natural course of the disease and to contribute to the development of treatment strategies for acute hepatitis C virus.

METHODS

The diagnosis of acute hepatitis C virus in 60 patients was based on seroconversion to anti-hepatitis C virus antibodies or clinical and biochemical criteria and on the presence of hepatitis C virus RNA in the first serum sample.

RESULTS

Fifty-one of 60 (85%) patients presented with symptomatic acute hepatitis C virus. In the natural (untreated) course of acute symptomatic hepatitis C (n = 46), spontaneous clearance was observed in 24 patients (52%), usually within 12 weeks after the onset of symptoms, whereas all asymptomatic patients (n = 9) developed chronic hepatitis C. The start of antiviral therapy (interferon-alpha with or without ribavirin) beyond 3 months after the onset of acute hepatitis induced sustained viral clearance in 80% of treated patients.

CONCLUSIONS

The management of acute hepatitis C has to take into account the high rate of spontaneous viral clearance within 12 weeks after the onset of symptomatic disease. Treatment of only those patients who remain hepatitis C virus RNA positive for more than 3 months after the onset of disease led to an overall viral clearance (self-limited and treatment induced) in 91% of patients, and unnecessary treatment was avoided in those with spontaneous viral clearance. Patients with asymptomatic acute hepatitis C virus infection are unlikely to clear the infection spontaneously and should be treated as early as possible.

Natural course of acute hepatitis C: a long-term prospective study

BACKGROUND

Acute hepatitis C has a high chronicity rate which appears to be significantly reduced by early antiviral treatment. However, it is unclear if all acutely infected patients should be treated, and when. In this prospective study, patients with a well-documented diagnosis of acute hepatitis C were evaluated to define the natural course, the rate of chronicity, and host and virus-related factors which might predict a self-limiting or chronic evolution requiring early antiviral treatment.

METHODS

From 1995 to 2000, 40 consecutive patients with a community-acquired AHC were enrolled. Liver tests, anti-hepatitis C virus antibodies and hepatitis C virus RNA levels were monitored. Median follow-up was 35 months (range 12-68).

RESULTS

A total of 24/40 patients had symptomatic disease including 20 with jaundice; 13/40 patients had prompt serum hepatitis C virus RNA clearance and ALT normalisation within 12 weeks; in 12/13 patients this pattern remained unchanged during follow-up. Overall, 27/40 patients remained hepatitis C virus RNA positive with fluctuating ALT levels. Older age and jaundice were predictive of resolution whereas there was no correlation with other host factors, viral genotype or viral load.

CONCLUSIONS

Our data demonstrate that spontaneous resolution can occur in about 30% of AHC patients. This favourable outcome rarely occurs in patients with anicteric AHC or in those with jaundice but with persistent viremia for more than 12 weeks from onset; early antiviral treatment for these patients may avoid or reduce chronicity.

[Role of interferons in the treatment of hepatitis B and hepatitis C virus infections]

BACKGROUND

Since the discovery of hepatitis C (HCV), the efficacy of treatment has significantly progressed using standard mono-therapy: with Interferon alpha (IFN) during six months we obtained approximately 10% sustained response and currently with the association of pegylated IFN and Ribavirin a 55% sustained response was achieved.

CURRENT POSITION AND MAJOR POINTS

HCV infection continues to present therapeutic problems which have not entirely been solved, mainly related to clinical and biological tolerance, and non-responders. Moreover, the care of patients with extra-hepatic localization, cirrhotic patients, as well as therapeutic problems of co-infected HIV-HCV patients. As regards hepatitis B (HBV) new effective treatments against this virus have appeared, IFN then nucleoside analogs, some of which are available in France (i.e. lamivudine, adefovir, dipovoxil). The main objective of chronic hepatitis B treatment is to obtain the complete inhibition of the HBV virus by Hbe-antigen antibody seroconversion which would therefore significantly increase patient survival. In this article the advantages and disadvantages of the different treatments are assessed.

FUTURE PERSPECTIVES

Despite the considerable and rapid progress obtained in the therapeutic treatment of infection due to HCV and HBV a number of unknown factors remain, which warrants further trials, in particular to evaluate the efficacy as well as the tolerance of the antiviral agent association.

Interferon for interferon naive patients with chronic hepatitis C

BACKGROUND

A previous meta-analysis of interferon therapy in naive patients with chronic hepatitis C has documented its efficacy in achieving virologic clearance, and improving liver biochemistry and histology; however, since its publication additional trials have been reported.

OBJECTIVES

To evaluate the response to interferon in interferon naive patients with chronic hepatitis C. The effect of treatment dose and duration, and the response in patients with cirrhosis and those with normal aminotransferases was also investigated.

SEARCH STRATEGY

The Cochrane Controlled Trials Register (Cochrane Library Issue 1, 1999), MEDLINE (January 1966 to December 1999), and reference lists were searched, and pharmaceutical companies were contacted for unpublished trials.

SELECTION CRITERIA

Randomised clinical trials comparing interferon with placebo, no treatment, or different regimens of interferon were selected. Abstracts were excluded.

DATA COLLECTION AND ANALYSIS

The primary outcome measure was sustained disappearance of serum HCV RNA (virologic sustained response (SR)). Biochemical and end of treatment responses, liver histology, and adverse events were also recorded. Assessment of drug efficacy used the methods of Peto and Der Simonian and Laird.

MAIN RESULTS

Fifty-four trials enrolling 6545 patients were included. Compared with no treatment, interferon 3 MU thrice weekly for 12 months increased the probability of a virologic SR (Peto odds ratio (OR) 4.60; 95% confidence interval (CI) 1.53 to 13.85). At this dosage and duration of therapy, the rate of virologic SR was 17% (95% CI 10 to 28%) in interferon-treated patients versus 3% (95% CI 1 to 10%) in controls. A dose of 6 MU was more effective than 3 MU thrice weekly (OR for 12 months treatment, 2.21; 95% CI 1.10 to 4.45), as were durations of 12 months or greater versus six months (OR 1.87; 95% CI 1.30 to 2.67). Adverse events were more common with higher doses and prolonged durations of treatment. Compared with no therapy, interferon increased the probability of histologic improvement (OR 9.22; 95% CI 5.69 to 14.94). The response to interferon in cirrhotic patients (virologic SR, 17%; 95% CI 11 to 26%) was similar to that in non-cirrhotic patients. However, interferon was no more effective than control in patients with normal aminotransferases.

REVIEWER'S CONCLUSIONS

Interferon is effective in achieving viral clearance and improving liver biochemistry and histology in interferon naive patients with chronic hepatitis C. Higher doses and prolonged durations are more effective, but associated with more frequent adverse events. Interferon is associated with similar benefits in patients with cirrhosis, but the efficacy in patients with normal aminotransferases is unproven.

Interferon for acute hepatitis C

BACKGROUND

Acute hepatitis C virus (HCV) infection progresses to chronicity in the majority of patients. In order to prevent the progression to chronic disease, several studies have assessed interferon in patients with acute hepatitis C.

OBJECTIVES

The aim of this review was to assess the efficacy of interferon in acute HCV infection.

SEARCH STRATEGY

We searched MEDLINE, the Cochrane Controlled Trials Register, and the abstracts of the American Association for the Study of Liver Diseases (June 2001). We also contacted pharmaceutical companies to obtain unpublished trials.

SELECTION CRITERIA

Randomised clinical trials comparing interferon with placebo or no treatment, and published as an article, abstract, or letter were selected. No language limitations were used.

DATA COLLECTION AND ANALYSIS

Two reviewers independently assessed trial quality and extracted data. The following endpoints were analysed: normalization of alanine aminotransferase (ALT) activity at the end of treatment (biochemical ETR); sustained ALT normalization at the end follow-up (biochemical SR); disappearance of serum HCV RNA by polymerase chain reaction assay at the end of treatment (virologic ETR) and at the end of follow-up (virologic SR). Histologic data and adverse events were also recorded. Assessment of drug efficacy used the methods of Peto and Der Simonian and Laird.

MAIN RESULTS

Six randomised trials involving 206 patients with acute hepatitis C met the inclusion criteria. Four trials assessing interferon alfa-2b in 141 patients, all with transfusion-acquired acute hepatitis C, were included. They demonstrated no significant heterogeneity in the outcomes assessed. When compared with no treatment, interferon alfa-2b was associated with an increase in the rates of virologic ETR and SR by 45% (95% CI 31-59%, P < 0.00001) and 29% (95% CI 14-44%, P = 0.0002), respectively. The virologic ETR was 42% (95% CI: 30-56%) in the interferon alfa-2b group versus 4% (95% CI 0-13%, P < 0.00001) in the control group. At the end of follow-up, a virologic SR was seen in 32% (95% CI 21-46%) of interferon-treated patients versus only 4% (95% CI 0-13%, P = 0.00007) of controls. The tolerability of therapy, or the impact of interferon alfa-2b on hepatic histology, was not reported. Two trials assessed interferon beta in a total 65 patients. The efficacy of interferon beta could not be assessed, however, due to heterogeneity of these trials.

REVIEWER'S CONCLUSIONS

Interferon alfa is effective in improving biochemical outcomes and achieving sustained virologic clearance in patients with transfusion-acquired acute hepatitis C. The effect on long-term clinical outcomes could not be assessed due to limitations in the current data.

Combination therapy with interferon-alpha and ribavirin for hepatitis C: practical treatment issues

Combination therapy with ribavirin and interferon (IFN)-alpha for 6 to 12 months is currently the treatment of choice for chronic hepatitis C infection. The overall sustained response rate to treatment, defined as loss of hepatitis C virus (HCV) from serum 6 months after completion of treatment, is 40%. The indications for treatment are serum HCV RNA positivity, abnormal serum transaminases and the presence of portal fibrosis and/or moderate/severe inflammation. Response rates are lower in genotype 1 than in genotype 2 or 3 and in the presence of a high viral load. Anaemia is the most common adverse event and is due to ribavirin; neuropsychiatric adverse effects due to IFNalpha lead to premature cessation of therapy in 10 to 20% of patients. The current recommended dose of interferon is 3MU given subcutaneously 3 times a week. However, it is likely that longer-acting pegylated interferons, which may be more effective and can be administered once weekly, will in the future replace currently used IFNalpha.

Trends in bloodborne pathogen exposure and follow-up at an urban teaching hospital: 1987 to 1997

Health care workers (HCWs) risk occupational exposure to bloodborne pathogens. Effective postexposure treatment and testing depend on compliance with follow-up, but compliance rates are poorly understood. We examined trends in exposure and follow-up at a large teaching hospital after interventions to improve compliance. We reviewed exposures from October 1987 to September 1988 (group 1) and July 1996 to June 1997 (group 2). Data were analyzed for HCW demographics, source patient characteristics, and follow-up outcomes. We found that group 2 source patient serologic data were obtained more often. Group 1 source patients were more likely to be positive for the human immunodeficiency virus (HIV). Group 2 HCWs were more likely to be immune to hepatitis B virus, to agree to HIV testing, and to comply with follow-up. Follow-up rates remained suboptimal, even after high-risk exposures. Non-licensed HCWs were less likely to accept postexposure testing than physicians or nurses in group 2. General and targeted interventions to improve compliance and follow-up are still needed.

Management of occupational exposures to hepatitis C virus: current practice and controversies

Unlike hepatitis B virus and human immunodeficiency virus, there currently are no immunization or chemoprophylactic interventions available to prevent infection after an occupational exposure to hepatitis C virus (HCV). A "Reality Check" session was held at the 4th Decennial International Conference on Nosocomial and Healthcare-Associated Infections to gather information on current practices related to management of occupational exposures to HCV, generate discussion on controversial issues, and identify areas for future research. Infection control professionals in attendance were knowledgeable in most issues addressed regarding the management of occupational exposures to HCV. Areas of controversy included the use of antiviral therapy early in the course of HCV infection and the appropriate administrative management of an HCV-infected healthcare worker.

Meta-analysis of interferon randomized trials in the treatment of viral hepatitis C in naive patients: 1999 update

The aim of this study was to update our previous meta-analysis of interferon (IFN) in the treatment of hepatitis C and to analyse new factors, namely, HCV RNA end-point, patients with cirrhosis and patients with normal ALT. We use the Der Simonian and Laird method, with heterogeneity and sensitivity analyses. Seventy-six randomized control trials (RCTs) in naive patients were found but we focused our analysis on 59 RCTs with chronic hepatitis C (26 vs. controls and 33 comparing different regimens) and on seven RCTs in acute hepatitis. Interferon-alpha (IFN-alpha) at 3 MU thrice weekly (TIW) for 12 months exhibited 39% of virological end-of-treatment response (ETR) and 17% of virological sustained response (SR), respectively, vs. 1% and 3% in untreated controls (all P < 0.001). There was a significant dose effect (in favour of 6 vs. 3 MU TIW): the virological SR at 6 months were 35% in the 6 MU group (95% CI: 24-47) and 16% in the 3 MU group (95% CI: 8-27) and were at 12 months 43% in the 6 MU group (95%CI: 31-56) and 25% in the 3 MU group (95% CI: 16-37). There was a significant duration effect (12 vs. 6 months) upon the virological SR rate both at 3 and 6 MU: 3 MU provided 14% of virological SR (95% CI: 11-19) in the 12 months group vs. 7% (95% CI: 5-11) in the 6 months group and 6 MU provided 22% (95% CI: 17-29) and 16% (95% CI: 11-22) virological SR in the 12 and 6 months groups, respectively. Cirrhotic treated patients had 17% of virological SR (95 CI: 9-24%; P < 0.001) vs. 0% in controls and provided a 20% reduction rate (95 CI: -2% to -37%, P=0.03) in hepatocellular carcinoma incidence. In acute hepatitis C, a 3-month treatment with IFN-alpha showed significant efficacy vs. controls upon the virological SR rate (32% vs. 4%, P < 0.001). In conclusion, we confirm the dose and duration effect of IFN in chronic hepatitis C, and the efficacy of IFN-alpha in the treatment of acute hepatitis and in cirrhotic patients.

Interferon therapy in haemodialysis patients with acute hepatitis C virus infection and factors that predict response to treatment

In view of the high rate of chronicity of acute hepatitis C and the low efficacy of interferon (IFN) treatment in advanced liver disease, it may be beneficial to treat patients during the acute phase of the infection. Here we assessed the effects of variable-dose IFNalpha-2b treatment in haemodialysis patients with acute hepatitis C virus (HCV) infection, and identified factors that may predict response to this therapy. The study population included 67 patients, but 14 were excluded due to side-effects or because they were lost to follow-up. Seventeen patients who received no specific treatment were used as controls (Group 1). Sixteen and 20 patients received low-(3 MU) and high-dose (6-10 MU) IFNalpha-2b three times weekly for 3 months (Groups 2 and 3, respectively). Virological end-of-treatment response (ETR) was observed in 1 (5.6%), 13 (56.5%), and 17 (65.4%) patients in Groups 1, 2, and 3, respectively, and virological sustained response (SR) was observed in 1 (5.6%), 6 (26.1%), and 13 (50%) patients in the three groups. The rates of virological ETR and SR in the treated groups were significantly higher than those of the control group (P < 0.01 for all comparisons). In multivariate logistic regression analysis, single stranded confirmational polymorphysm (SSCP) band number (P=0.02) was the only factor that was significantly associated with virological SR. In conclusion, IFN-alpha treatment initiated during the acute phase of HCV infection is associated with a higher rate of virological ETR and SR. This study suggested that quasispecies heterogeneity has predictive value with regard to virological SR.

Acute Viral Hepatitis

The mainstay of treatment for acute viral hepatitis is supportive care, as most cases are self-limited. General measures in all types of acute viral hepatitis include bedrest if the patient is very symptomatic, a high-calorie diet, avoidance of hepatotoxic medications, and abstinence from alcohol with the anticipation that most patients will recover uneventfully. In severe cases, hospitalization may be necessary for intravenous rehydration if the patient is unable to maintain adequate oral intake due to nausea and vomiting or if there is any alteration of mental status to suggest evolving fulminant hepatic failure. Acute hepatitis A is a self-limited disease, but can be fulminant. Lamivudine at a dosage of 100 mg/d orally may be beneficial in acute hepatitis B. Interferon-alpha therapy in acute hepatitis C may decrease the risk of developing chronic hepatitis C. Fulminant liver failure due to acute viral hepatitis is uncommon, but orthotopic liver transplantation occasionally may be life saving.

Viral hepatitis. From prevention to antivirals

The challenge of viral hepatitis has been acknowledged and confronted in the last decade. Significant progress in prevention of infection with HAV and HBV may eradicate these serious infections from the United States and other parts of the world in the coming decades. Application of prophylactic strategies to children will be a major mechanism in accomplishing this task. The quest for potent antiviral medications continues. The next critically important development will be ways to prevent new HCV infections and to treat the millions of already infected individuals at risk for the serious consequences of this disease. For pediatricians, realizing these goals requires a greater understanding of perinatal HCV transmission, use of vaccines for prevention of viral hepatitis, and identification of HCV-infected children who are likely to benefit from new therapeutic strategies as they become available.

Risk and management of blood-borne infections in health care workers

Exposure to blood-borne pathogens poses a serious risk to health care workers (HCWs). We review the risk and management of human immunodeficiency virus (HIV), hepatitis B virus (HBV), and hepatitis C virus (HCV) infections in HCWs and also discuss current methods for preventing exposures and recommendations for postexposure prophylaxis. In the health care setting, blood-borne pathogen transmission occurs predominantly by percutaneous or mucosal exposure of workers to the blood or body fluids of infected patients. Prospective studies of HCWs have estimated that the average risk for HIV transmission after a percutaneous exposure is approximately 0.3%, the risk of HBV transmission is 6 to 30%, and the risk of HCV transmission is approximately 1.8%. To minimize the risk of blood-borne pathogen transmission from HCWs to patients, all HCWs should adhere to standard precautions, including the appropriate use of hand washing, protective barriers, and care in the use and disposal of needles and other sharp instruments. Employers should have in place a system that includes written protocols for prompt reporting, evaluation, counseling, treatment, and follow-up of occupational exposures that may place a worker at risk of blood-borne pathogen infection. A sustained commitment to the occupational health of all HCWs will ensure maximum protection for HCWs and patients and the availability of optimal medical care for all who need it.

Risk and management of blood-borne infections in health care workers

Exposure to blood-borne pathogens poses a serious risk to health care workers (HCWs). We review the risk and management of human immunodeficiency virus (HIV), hepatitis B virus (HBV), and hepatitis C virus (HCV) infections in HCWs and also discuss current methods for preventing exposures and recommendations for postexposure prophylaxis. In the health care setting, blood-borne pathogen transmission occurs predominantly by percutaneous or mucosal exposure of workers to the blood or body fluids of infected patients. Prospective studies of HCWs have estimated that the average risk for HIV transmission after a percutaneous exposure is approximately 0.3%, the risk of HBV transmission is 6 to 30%, and the risk of HCV transmission is approximately 1.8%. To minimize the risk of blood-borne pathogen transmission from HCWs to patients, all HCWs should adhere to standard precautions, including the appropriate use of hand washing, protective barriers, and care in the use and disposal of needles and other sharp instruments. Employers should have in place a system that includes written protocols for prompt reporting, evaluation, counseling, treatment, and follow-up of occupational exposures that may place a worker at risk of blood-borne pathogen infection. A sustained commitment to the occupational health of all HCWs will ensure maximum protection for HCWs and patients and the availability of optimal medical care for all who need it.

Primer on hepatitis C for hospital epidemiologists

First identified in the late 1980s as the main causative agent of non-A, non-B hepatitis, hepatitis C virus (HCV) infection is now the most common chronic bloodborne infection in the United States. It is likely that the number of deaths attributable to HCV-related chronic liver disease will increase substantially during the next 2 decades, and the potential economic and clinical burden related to HCV is staggering. Accordingly, it is essential to identify risk factors for transmission of HCV and implement appropriate precautions to decrease the prevalence of this emerging infection. The relative importance of the two most common types of exposures associated with transmission of HCV, ie, blood transfusion and injection drug use, has evolved over time. Strict blood-donor selection and the use of reliable serological tests have led to a significant reduction in transfusion-associated risk. Injection drug use is currently the single most important risk factor for HCV infection in the United States. Transmission of HCV poses a serious threat to healthcare workers and patients if infection control techniques or disinfection procedures are inadequate. Potential exposures include contact of the eyes, mucous membranes, broken skin, or needlestick injury. Hospitalized patients may serve as a reservoir for transmission, and the prevalence of anti-HCV seropositivity among such patients can be as high as 20%. The infected healthcare worker is a potential source of transmission. A recent molecular phylogenetic analysis demonstrated that a cardiac surgeon likely transmitted HCV to five of his patients during open heart surgery. In summary, nosocomial transmission has been unequivocally confirmed and underscores the need for strict infection control practices.

Treatment of acute hepatitis C virus infection

Chronic hepatitis C is the leading cause of liver-related morbidity and mortality in the Western world. Treatment response in the chronic phase of the disease is still unsatisfactory. Acute hepatitis C takes a chronic course in more than 50% of cases. Interferon therapy treatment in the acute presentation phase is, according to some studies, more efficient than in the chronic phase of disease. The aim of this study was to analyse the response to interferon in acute hepatitis C. This review is based on three published meta-analyses performed using the methods of DerSimonian and Laird. Outcome was assessed by normalisation of serum aminotransferases and clearance of HCV-RNA. Data were presented by calculating the risk difference, which estimated efficacy by calculating the proportion of patients in treatment groups who responded better (0 to 1.0) or worse (0 to -1.0) than untreated control groups. Three mega units of interferon-a2b (IFN) three times a week for 6-24 weeks produced a significant response as measured by long-term normalisation of aminotransferases and clearance of HCV-RNA. Overall rate differences were +0.31 (p<0.01; 95% confidence interval +0.19-0.43) and +0.33 (p<0.001; 95% confidence interval +0.08-0.58). Six MU of IFN three times a week for 16-24 weeks produced better results with a risk difference of +0.53 (95% confidence interval +0.17-0.89) for normalisation of aminotransferases and +0.44 (95% confidence interval +0.06-0.82) for clearance of HCV-RNA. In an uncontrolled trial, 10 MU IFN daily for 4-6 weeks produced clearance of HCV-RNA and normalisation of transaminases in 90% of patients. Twelve weeks' treatment of symptomatic acute hepatitis C with interferon produced a response similar to that of long-term treatment for chronic hepatitis C. More studies are needed to define the role of a higher dose and the start of treatment.

Acute hepatitis C complicated by pancreatitis: another extrahepatic manifestation of hepatitis C virus?

In hepatitis C virus (HCV) infection a number of extrahepatic manifestations have been described, generally caused by immune phenomena. Here we report a case of acute pancreatitis, detected during an acute hepatitis C infection, in an elderly female patient.

Emergency department management of blood and body fluid exposures

Exposure to blood and body fluids that may be contaminated with infectious agents is a common occupational hazard for health care workers. Health care workers in the emergency department or out-of-hospital setting are at especially high risk for exposure to blood or body fluids. Nonemergency health care workers are frequently referred to hospital EDs for immediate treatment of occupation exposures. A series of recommendations by the Centers for Disease Control and Prevention evolved over the past decade, and changes are expected to continue. This state-of the-art article reviews current recommendations for management of persons exposed to blood or body fluids and discusses the scientific basis for recommendations regarding hepatitis B virus, hepatitis C virus, and HIV.

Quasispecies in viral persistence and pathogenesis of hepatitis C virus

Hepatitis C virus (HCV) is an important cause of chronic liver disease worldwide. This RNA virus circulates as a quasispecies and its genetic heterogeneity has been implicated in the lack of protective immunity against HCV and in its persistence following infection. HCV might escape from immune surveillance by developing mutations in proteins that are subject to immune pressure.

Risk and prevention of hepatitis C virus infection. Implications for dentistry

BACKGROUND

The occupational risk of hepatitis C virus, or HCV, infection in dentistry is very low. Nonetheless, the lack of an effective vaccine, the high rates of chronic infection and the limited effectiveness of treatment may cause concern for dental workers who come into contact with blood in their daily practices.

DESCRIPTION OF THE DISORDER

The authors discuss the natural history, diagnosis and treatment, and patterns of transmission of HCV infection, including the Centers for Disease Control and Prevention's recommendations for management and follow-up of health care workers after occupational exposure to HCV.

CLINICAL IMPLICATIONS

In the absence of an effective vaccine or postexposure prophylaxis, prevention of occupational transmission of HCV in dental settings continues to rely on the use of universal precautions, including barrier precautions and the safe handling of sharp instruments.

Hepatitis C virus infection: Review and implications for the dentist

OBJECTIVE

The purpose of this report was to review the current literature on hepatitis C virus infection, with particular attention to the aspects of interest for dental health care staff.

MATERIAL AND METHODS

The authors searched original research and review articles on specific aspects of hepatitis C virus infection, including articles on virology, epidemiology, transmission, diagnosis, natural history, extrahepatic manifestations, therapy and oral aspects of hepatitis C virus infection. The relevant material was evaluated and reviewed.

RESULTS

Hepatitis C virus is an RNA virus that is present throughout the world and has major geographic variations. The virus, transmitted mainly by means of blood contact, causes chronic hepatitis in up to 80% of cases and may give rise to hepatic cirrhosis and hepatocellular carcinoma in a significant proportion of patients. Although it is of limited efficacy, interferon alpha is currently the drug of choice in the treatment of the infection. Hepatitis C virus infection is associated with a number of extrahepatic manifestations that may include oral diseases such as lichen planus or sialadenitis. Although there are documented cases of nosocomial transmission to health care workers after percutaneous exposure, the prevalence of hepatitis C virus among dental staff members is probably similar to that in the general population.

CONCLUSION

Hepatitis C virus infection is a relatively common infection worldwide (1.4% in the US general population) that causes significant chronic hepatic disease. The dentist is thus likely to face a growing number of patients with a diagnosis of hepatitis C virus infection. For this reason it is essential for dental health care workers to be aware of the principal features of the disease and of its oral and dental implications.

Interferon therapy for acute hepatitis C viral infection--a review by meta-analysis

BACKGROUND

Hepatitis C viral (HCV) infection poses a major health problem for Australia. Currently interferon therapy is approved only for people with chronic infection, yet the literature contains a number of studies that show that there is a better response to interferon in symptomatic acute HCV.

AIM

To review the response to interferon therapy in acute HCV by way of meta-analysis.

METHODS

This study was a retrospective review of the data on the use of interferon therapy in acute HCV. The meta-analysis was performed using the methods of DerSimonian and Laird. Data were presented by calculating the risk difference which estimated efficacy by calculating the proportion of patients in treatment groups who responded better (0 to +1.0) or worse (0 to -1.0) than untreated control groups.

RESULTS

A meta-analysis of six studies on the use of 3MU of interferon alpha 2b (IFN-alpha 2b) three times a week for six to 24 weeks showed a significant response as measured by long term (> 12 months) normalisation of alanine aminotransferase (ALT) and clearance of HCV RNA (as measured by polymerase chain reaction). The risk of difference was +0.31 (95% CI of +0.19 to +0.43, p < 0.01) and +0.33 (95% CI of +0.08 to +0.58, p < 0.001) respectively. Slightly better results were seen with daily doses of 3MU of interferon beta (IFN-beta) given intravenously over four to seven weeks. This produced a risk difference of +0.57 (95% CI of +0.26 to +0.88, p < 0.02) for normalisation of ALT and +0.83 (95% CI of +0.61 to 1.00, p < 0.001) for clearance of HCV. Results for higher daily doses of both IFN alpha and beta were limited to a few studies and most were uncontrolled. 6MU of IFN-alpha 2b three times a week for 16 to 24 weeks produced a risk difference of +0.53 (95% CI +0.17 to +0.89, p < 0.05) for normalisation of ALT and +0.44 (95% CI +0.06 to +0.82) for clearance of HCV RNA. Results with 6MU daily for eight weeks of IFN-beta in an uncontrolled study, showed up to 90% patients cleared HCV long term. Preliminary results with 10MU of IFN-alpha 2b daily for four to six weeks also showed long term clearance of HCV RNA and normalisation of ALT in 90% of treated patients.

CONCLUSION

Short term (six weeks to six months) treatment of symptomatic acute HCV with interferon (both alpha and beta) produced a better long term response rate than prolonged therapy (> 12 months) in chronic HCV. Daily doses of 6MU and 10MU produced better responses than 3MU but more studies are needed to determine the optimum regime.

[Therapy of hepatitis C]

The purpose of this review is an update of the therapy of hepatitis C especially with Interferon-alpha. From the large number of publications on this topic the established facts were worked out. Taking these facts as a base guidelines for the therapy in practical use were defined. In addition the aspects of therapeutic strategies of chronic hepatitis C which until now can not definitely be judged are discussed. In the relatively few patients in whom hepatitis C is diagnosed already in the acute phase, Interferon-alpha-treatment (3 x 3 million units 3 times a week) for 3 to 4 months increases the percentage of patients in whom HCV-RNA in the serum is eliminated. In patients with chronic hepatitis C, after decision finding for treatment, a standard scheme is recommended which consists of a monotherapy with recombinant Interferon-alpha. The dosage of Interferon-alpha is in the first 12 to 16 weeks 5 up to 6 million units given 3 times a week. For the further therapy 3 million units 3 times a week seems to be appropriate. The recommended duration of Interferon-alpha-therapy is 12 months. A long-term benefit of about 20% can be achieved in unselected groups of patients when judged on the permanent normalisation of serum transaminases and elimination of HCV-RNA in the serum. Important factors which may influence the probability of a sustained response, like HCV genotype, virus titer in serum, duration of the disease, high hepatic iron content and the presence of cirrhosis, are discussed. Up to now there exist no reliable guidelines in the case of a "no change" situation and for patients with a flare-up of inflammatory activity during or after therapy. Combination therapy of Interferon-alpha with other drugs like analogous of nucleotides (for example ribavarin), non steroidal antirheumatic drugs and ursodesoxycholic acid (UDCA) have still to be evaluated in controlled clinical trials.