Interferon treatment of chronic hepatitis C

Retrospective Comparative Study of Topical Interferon α2b Versus Mitomycin C for Primary Ocular Surface Squamous Neoplasia

PURPOSE

To compare the efficacy and safety of topical interferon alpha 2b (IFNα2b) and mitomycin C (MMC) for ocular surface squamous neoplasia.

METHODS

In this retrospective study, medical records of 51 eyes of 50 patients with a diagnosis of primary ocular surface squamous neoplasia were included. All cases were treated with either topical IFNα2b (1 million IU/mL) or MMC (0.4 mg/mL) 4 times a day. The primary outcome measure was frequency of clinical resolution of tumors along with failure and recurrence rates after treatment. Other outcome measures included the duration of treatment and adverse effects associated with both topical therapies.

RESULTS

Twenty-six eyes were treated with topical IFNα2b and 25 eyes were treated with topical MMC. A complete response was achieved in 23 (89%) and 23 (92%) eyes with topical IFNα2b and MMC, respectively (P = 0.67). The median time to lesion resolution was significantly different between the groups (median 3.5 months in the IFNα2b group and 1.5 months in the MMC group) with an average difference of 1.7 months (P < 0.005). Five (10%) of 51 patients showed no or partial response to topical therapy. Subsequently, they underwent surgical excision. Adverse effects occurred in 3 (12%) patients using IFNα2b and 22 (88%) patients using MMC (P < 0.005).

CONCLUSIONS

Both IFNα2b and MMC seemed to be equally effective topical monotherapies. Despite a prolonged time to lesion resolution, IFNα2b-treated eyes had better safety and tolerance in comparison with MMC-treated eyes.

Topical interferon alpha-2b for treatment of noninvasive ocular surface squamous neoplasia with 360° limbal involvement

PURPOSE

To report the results of topical interferon alpha-2b (IFNα2b) for the treatment of ocular surface squamous neoplasia (OSSN) with 360° limbal involvement.

METHODS

In a prospective observational study, five patients with biopsy proven primary or recurrent OSSN with 360° limbal involvement received topical IFNα2b (3 million IU/ml, 4 times daily) and were followed from 8 to 12 months. Outcome measures included resolution of the lesion, relief of symptoms, systemic and ocular side effects, and recurrence rate.

RESULTS

Five patients including 4 primary OSSNs and one recurrent OSSN received topical interferon alpha-2b. The mean age was 60.2 (range: 52-73) years and mean follow up duration was 10.2 months. Clinical resolution of the tumor occurred in all cases 2 months after initiation of treatment and no patient developed ocular or systemic complications. No recurrence of OSSN developed during the follow up period.

CONCLUSION

Topical recombinant IFNα2b appears to be an effective alternative treatment for OSSN with 360° limbal involvement. This approach precludes the high risk of limbal stem cell deficiency which results from surgical excision or topical chemotherapeutic agents.

A model for the hepatitis C virus envelope glycoprotein E2

Several experimental studies on hepatitis C virus (HCV) have suggested the envelope glycoprotein E2 as a key antigen for an effective vaccine against the virus. Knowledge of its structure, therefore, would present a significant step forward in the fight against this disease. This paper reports the application of fold recognition methods in order to produce a model of the HCV E2 protein. Such investigation highlighted the envelope protein E of Tick Borne Encephalitis virus as a possible template for building a model of HCV E2. Mapping of experimental data onto the model allowed the prediction of a composite interaction site between E2 and its proposed cellular receptor CD81, as well as a heparin binding domain. In addition, experimental evidence is provided to show that CD81 recognition by E2 is isolate or strain specific and possibly mediated by the second hypervariable region (HVR2) of E2. Finally, the studies have also allowed a rough model for the quaternary structure of the envelope glycoproteins E1 and E2 complex to be proposed. Proteins 2000;40:355-366.

Iron depletion is not effective in inducing a virologic response in patients with chronic hepatitis C who failed to respond to interferon therapy

OBJECTIVE

Some studies have suggested that increased iron stores may impact negatively on the response to interferon in patients with chronic hepatitis C infection. We performed this prospective trial to determine the effects of iron depletion on ALT and HCV-RNA levels in patients with chronic hepatitis C infection and to assess whether the response to interferon in patients who had previously failed to respond to interferon was enhanced by iron depletion.

METHODS

Patients with chronic hepatitis C resistant to interferon therapy and no evidence of iron overload underwent weekly phlebotomies until the serum ferritin level was below lower limits of normal for the subject's age and sex. Patients were then started on interferon-alpha2b, 3 million units subcutaneously three times per week for a period of 24 weeks. Iron studies, ALT, and HCV-RNA levels were monitored at baseline, after phlebotomy and at 12 and 24 weeks of interferon therapy.

RESULTS

Thirty-three patients were enrolled, 28 completed the study. A mean of 7.2 units of blood were removed to achieve iron depletion. ALT levels decreased significantly with phlebotomy (142 IU/L before phlebotomy vs 82 IU/L after phlebotomy; p < 0.001), but log HCV-RNA levels remained unchanged (6.49 before phlebotomy vs 6.51 after phlebotomy). Interferon therapy did not improve ALT levels further. HCV-RNA levels were minimally reduced during interferon therapy (log HCV-RNA 6.49 before interferon vs 6.00 after 24 weeks of interferon therapy). Two patients achieved a virologic end of treatment response, both relapsed within 3 months after discontinuation of interferon. No patient achieved a sustained virologic response.

CONCLUSIONS

In patients who previously failed treatment with interferon, iron depletion induced by phlebotomy improves ALT levels but is ineffective in achieving viral eradication in patients retreated with interferon 3 million units three times per week.

Interferon alfa subtypes and levels of type I interferons in the liver and peripheral mononuclear cells in patients with chronic hepatitis C and controls

Viral infections stimulate the transcription of interferon type I, which includes IFN-alfa (IFN-alpha) (13 subtypes) and IFN-beta (a single substance). Hepatitis C virus (HCV) infection is remarkable by its ability to evade host antiviral defenses; however, there is little information as to whether endogenous IFN is activated or not in this disease. Additionally, despite the fact that the various IFN-alpha subtypes may differ in biological activity, there are no data concerning the IFN-alpha subtypes specifically expressed in normal and diseased liver tissue. Thus, we have analyzed the IFN-alpha subtypes and the mRNA levels of type I IFNs in samples of normal liver tissue and in liver from patients with chronic hepatitis C. Similar studies were performed in peripheral blood mononuclear cells (PBMC) from patients and controls. After amplification and cloning of IFN-alpha cDNA, we observed that 98 of the 100 clones from normal liver tissue corresponded to the IFN-alpha5 subtype. However, in livers with chronic hepatitis C and in PBMC from controls and patients, a variety of subtypes, in addition to IFN-alpha5, were detected, suggesting a participation of infiltrating leukocytes in the production of IFN-alpha in livers with chronic hepatitis C. As compared with controls, patients with chronic hepatitis C showed a significant increase in IFN-beta mRNA in both the liver and PBMC, while IFN-alpha mRNA was significantly increased in PBMC but markedly reduced in liver tissue. In conclusion, IFN-alpha5 is the sole IFN-alpha subtype expressed in normal liver tissue. The hepatic levels of IFN-alpha are reduced in chronic hepatitis C, an event that may favor viral persistence.

Case report: interferon induced coma in Sheehan's syndrome

A 54-year-old woman who was being treated with 10 million units (mu) of natural interferon (IFN)-alpha per day for chronic active hepatitis C at a local clinic, developed coma on the fourth day of treatment. On admission to Yamagata University Hospital, she was still in a state of semicoma with severe hyponatraemia (122 mEq/L) and hypochloraemia (89 mEq/L). After the administration of electrolytes, her condition improved remarkably. Endocrinological loading tests showed a hypofunction of the anterior pituitary gland. In consideration of these results, and her past experiences of haemorrhage during childbirth and subsequent amenorrhoea, we diagnosed her illness as a coma as a result of Sheehan's syndrome which had become overt during IFN therapy. She recovered completely after treatment with hydrocortisone and l-thyroxine.

Viral hepatitis in older adults

The objective of this paper is to review the epidemiology, manifestations, therapy, and prevention of viral hepatitis in older people and to discuss issues of prevention and management. In developed countries a significant portion of the adult population is not immune to Hepatitis A virus (HAV). Morbidity and mortality from HAV infection increases with age. A safe and effective hepatitis A vaccine is available and health authorities should consider immunization early in life and for healthy adults as well as for potential high risk groups such as nursing home residents. Acute hepatitis due to Hepatitis B virus (HBV) is rare in older people and is usually a mild disease. Most older patients with chronic HBV infection who suffer from advanced liver disease have no evidence of ongoing viral replication. Therefore, they are not candidates for interferon therapy. Those with evidence of ongoing viral replication and compensated liver disease should be offered interferon or be included in clinical trials with new antiviral drugs such as lamivudine. Since the response rate to hepatitis B vaccination decreases with age, developing vaccines with greater immunogenicity is crucial. Hepatitis C virus (HCV) is the most frequent cause of acute viral hepatitis in older people. Acute hepatitis C is usually a mild disease in this age group. Because many older patients with chronic HCV infection have compensated liver disease, they could benefit from antiviral therapy. In light of the low response rate to interferon in older patients with chronic hepatitis C and the side effects of the drug, interferon therapy should be reserved for those with the best chance of response. "Combination" antiviral therapy should be on trial for older patients with chronic HCV infection who do not respond to interferon. The recently discovered RNA virus, Hepatitis G (HGV), has been associated with liver disease in older people. It's role in the pathogenesis of liver injury remains to be elucidated.

Long-term outcome of hepatitis C virus infection after liver transplantation

We analyzed the long-term clinical course of 71 patients with RNA-positive hepatitis C virus (HCV) infection after liver transplantation. Patients with reinfection after transplantation for HCV-related liver disease, or de novo infection at transplantation were followed for up to 12 years. Cumulative survival for patients with HCV infection at 2, 5, and 10 years after transplantation was 67%, 62%, and 62%, respectively. It was not significantly different from that in patients transplanted for other nonmalignant diseases without HCV infection. The main factor determining long-term survival was the presence or absence of hepatocellular carcinoma (HCC) at transplantation. The 5-year survival rate for HCV patients with or without HCC was 35% versus 73%, respectively (P < .05). No deaths because of viral hepatitis of the graft were observed. Deaths in the first year after transplantation were caused by infectious complications, cardiovascular problems, or rejection; deaths after more than 12 months were exclusively because of recurrence of HCC. Biochemical and histological evidence of hepatitis was found in the majority of the patients, only 16% had normal alanine aminotransferase (ALT) values throughout. Twenty-two percent of patients complained of symptoms, with hepatitis C being the cause in 82% of these. Two patients lost their HCV-RNA for prolonged, ongoing periods of time. The severity of the posttransplantation hepatitis was unrelated to age, sex, severity of liver disease before transplantation, cold ischemic time of the graft, duration of the operation, transfusions, the number of rejection episodes, or the long-term immunosuppressive regime. Only initial short-term therapy with interleukin 2 (IL2) receptor antibodies adversely influenced inflammatory activity. Viral genotype did not influence the course of the graft hepatitis in our series. Histology showed inflammation in 88% of the biopsies and signs of fibrosis in 24%. Mean ALT values correlated with inflammation but not with fibrosis in the biopsies. Porto-portal bridging was observed in six patients, one patient developed cirrhosis within 2 years after orthotopic liver transplantation (OLT). We conclude that chronic hepatitis develops in the majority of patients with HCV infection after liver transplantation. Carrier states without significant laboratory abnormalities are observed in approximately 16%, biochemical abnormalities without symptoms are seen in 60%, and symptomatic disease develops in a quarter of the patients. The disease course closely resembles that seen in nontransplanted hepatitis C patients. It is generally mild but little over 10% of patients develop signs of fibrosis of the graft during the first decade.

Evaluation of Western Blot in Routine Diagnosis of Hepatitis C Virus

Hepatitis C virus (HCV) is among the major causes of parenterally transmitted hepatitis. Detection of infected persons would greatly diminish transmission rates and is therefore a significant parameter for prevention. Current assays are not able to resolve all cases and sometimes the results are controversial. The present study outlines problems that arise during routine testing. Two ELISA tests and three confirmatory tests were used and Polymerase Chain Reaction (PCR) data were available for some of the samples. The results of this study show that only 77.4% of samples positive for both ELISAs were confirmed as being positive. Controversial ELISA results remained controversial, depending on the confirmatory test used. PCR results, though not complete, point to the major problem of Western blot (WB) negative sera that prove positive for the viral genome and have to be excluded from screening for blood and organ donation. Since PCR cannot be used as a routine screening procedure, improvement of the routine assays is needed to minimize ambiguous results.

Mixed cryoglobulinemia as a model of systemic vasculitis

Leukocytoclastic vasculitis is the dominant lesion of mixed cryoglobulinemia (MC). The high prevalence of antibodies to hepatitis C virus (HCV) in association with the higher concentration of HCV RNA genomic sequences in the cryoglobulins suggests a close relationship between MC and HCV infection and strongly supports the view that this virus plays a key role in causing vascular damage. Analysis of the composition of immune complexes (ICs) provides evidence that cryoglobulins include virions mostly bound to IgG that is specifically reactive with HCV-related proteins, which in turn are crosslinked by monoclonal IgM with rheumatoid factor (RF) activity, frequently bearing the WA crossidiotype (XId). This structure is similar (if not identical) to that of circulating ICs from HCV-infected patients without cryoglobulins, suggesting that the virus may be directly responsible for the production of WA RF. Evidence for the role of circulating cryoproteins in the pathogenesis of cutaneous and renal vasculitis stems from the demonstration of HCV-related proteins and/or HCV RNA genomic sequences in the vessel wall of patients with MC. Our data indicate that endothelial cells are fully susceptible to infection by and replication of HCV, and support the contention that they serve as sufficient targets for the binding of HCV proteins expressed on the cell surface to serum immunoglobulins. The in situ demonstration of IgM RF WA XId adds further evidence that RF of the WA group participates in the development of vasculitis and probably stabilizes the binding of IgG antibodies. Lymphocytes may be crucial in the infection of endothelial cells by acting as a circulating viral reservoir. After encouraging initial results, controlled trials have defined the substantive efficacy of IFN-alpha in the treatment of MC. A response of IFN can be achieved in more than 50% of patients and includes improvement of cutaneous vasculitis and renal function. This clinical response is accompanied by a reduction in hepatitis C viremia, serum cryoglobulin concentration, and IgM RF synthesis. However, almost 80% of responders eventually have a clinical and biochemical relapse. Additional studies are required to improve the outcome and extension of this therapy, define the best candidates, and indicate the situations in which it is needed.

Elimination of hepatitis C virus RNA in infected human hepatocytes by adenovirus-mediated expression of ribozymes

Hepatitis C virus (HCV), a positive-strand RNA virus, is the major infectious agent responsible for causing chronic hepatitis. Currently, there is no vaccine for HCV infection, and the only therapy for chronic hepatitis C is largely ineffective. To investigate new genetic approaches to the management of HCV infection, six hammerhead ribozymes directed against a conserved region of the plus strand and minus strand of the HCV genome were isolated from a ribozyme library, characterized, and expressed from recombinant adenovirus vectors. The expressed ribozymes individually or in combination were efficient at reducing or eliminating the respective plus- or minus-strand HCV RNAs expressed in cultured cells and from primary human hepatocytes obtained from chronic HCV-infected patients. This study demonstrates the potential utility of ribozyme therapy as a strategy for the treatment of hepatitis C virus infection.

Evaluation and treatment of chronic hepatitis C infection

Hepatic C virus (HCV) has been recognized increasingly as a major public health crisis in the United States, causing infection in an estimated 3.5 million people and resulting in 8000 to 10,000 deaths annually from liver-related complications. This article focuses on the clinical aspects and diagnosis of hepatitis C, the importance of excluding other chronic liver diseases, and the current basis and strategy for treatment of HCV infection with interferon. Ideally, it will help primary care providers with the task of evaluating, diagnosing, teaching, and caring for patients with this chronic, potentially debilitating, and lethal disease.

Hepatitis C virus genotypes in the liver and serum of patients with chronic hepatitis C

OBJECTIVE: To evaluate the prevalence of hepatitis C virus (HCV) genotypes in a central area of Italy (Umbria); to analyze the correspondence of the genotypes detected in serum and liver samples; to study the relationship between HCV genotypes and severity of liver disease; to test whether co-infection with more than one HCV subtype could be influenced by the source of infection. METHODS: Genotyping by polymerase chain reaction with core-specific primers (Okamoto method) was performed in the serum and liver from 48 consecutive patients with histologically confirmed chronic C hepatitis. RESULTS: HCV genotype 1b was the prevalent strain and was not associated with more severe histologic damage. Data show a very good correspondence between genotypes identified in serum and liver specimens (91%). Mixed infections (with subtypes 1b and 2a) correlated significantly with intravenous drug abuse (p=0.001). CONCLUSION: We confirmed that subtype 1b is prevalent in central Italy. Co-infection with more than one subtype is not rare in intravenous drug abusers.

Hepatitis C virus RNA in peripheral blood mononuclear cells: relation with response to interferon treatment

The polymerase chain reaction (PCR) was used to investigate the presence of positive and negative hepatitis C virus (HCV) RNA strands in serum and peripheral blood mononuclear cells (PBMC) of 20 patients with histologically proven HCV-related chronic liver disease. All patients completed a course of interferon (IFN) treatment (6 MU of IFN-alpha 2b three times a week for 24 weeks) and were followed-up for 12 months after treatment was discontinued. Pre-treatment, end-treatment and 6-month follow-up serum and PBMC samples were examined. At enrollment, the positive strand of HCV-RNA was detected in serum of 18 patients (90%), the negative strand in none. Positive-stranded HCV-RNA was detected in PBMC of 15 patients (75%), 13 of whom also had detectable levels of negative-stranded HCV-RNA in PBMC. By the end of the treatment, 12 patients (60%) were responders. The pre-treatment HCV infection of PBMC, indicated by the presence of both RNA strands, was found in 8 (66.7%) responders compared to 5 (62.5%) non-responders (P = n.s.). End-treatment loss of PBMC HCV-RNA correlated significantly with the response since it occurred in all responders compared to 2 non-responders (P = 0.02). However, end-treatment-negative serum and PBMC HCV-RNA did not predict the occurrence of a sustained response, which was observed at month 12 in 5 of 12 responders (P = n.s.). On the other hand, the persistent absence of HCV RNA in serum and PBMC at the end of the 6-month follow-up was significantly associated with the occurrence of a sustained response (P < 0.0001).