Reciprocal interactions between human immunodeficiency virus and hepatitis C virus infections

Hepatitis C and human immune deficiency coinfection at the era of highly active antiretroviral therapy

Interactions between human immunodeficiency virus (HIV) and hepatitis C virus (HCV) have been widely studied before the introduction of highly active antiretroviral therapies (HAART). We reviewed the potential impact of HAART on hepatitis C as well as the interactions between HIV and HCV therapies. Physicians should be aware of the potential risk of: (i) symptomatic liver disease in HCV-HIV-coinfected patients at the era of triple antiretroviral therapy; (ii) potential liver deterioration paralleling immune restoration; (iii) lack of impact of triple antiretroviral therapy on HCV load; and (iv) potential drug-related hepatitis which may modify the natural history of HCV-related liver disease. Liver biopsies should be performed regularly in these patients in order to identify patients with severe liver disease who require early initiation of anti-HCV therapy under close monitoring of their immune status. Treatment is, to date, based on the combination of ribavirin and interferon with an expected sustained response rate around 25%. An important unresolved issue is to better delineate the temporal place of anti-HCV and anti-HIV antiviral therapies. At least in coinfected patients with significant liver disease, namely necro-inflammatory activity and/or fibrosis >or= 2, we believe that anti-HCV therapy is the priority since it lessens the risk of drug-induced hepatitis and of hepatitis due to immune restoration.

Evolution of coinfection with human immunodeficiency virus and hepatitis C virus in patients treated with highly active antiretroviral therapy

A retrospective analysis of data from a cohort of patients coinfected with human immunodeficiency virus (HIV) and hepatitis C virus (HCV) who were treated with highly active antiretroviral therapy (HAART) at 3 infectious diseases units in northern Italy was performed. While the patients were receiving HAART, CD4(+) cell counts significantly increased and HIV RNA serum levels decreased. However, no significant overall changes in alanine aminotransferase (ALT) levels and HCV RNA serum levels were observed. Fifteen (4.6%) of 323 patients died within 3 years of follow-up; death was related to cirrhosis in 5 patients (1.6%). No significant difference was observed between cirrhosis-related mortality and mortality related to other causes. Patients with ALT levels >4 times the normal values at initiation of HAART showed a significant decrease in ALT levels, whereas patients with normal ALT levels at initiation of HAART showed a significant increase over time, suggesting that HAART may have long-term beneficial or detrimental effects, depending on patient characteristics.

Prevalence of hepatitis C infection in Malawi and lack of association with sexually transmitted diseases

To investigate the role of sexual transmission for Hepatitis C virus (HCV) we studied its prevalence in sub-Saharan Africa where sexually transmitted diseases (STDs) are prevalent. Overall, HCV prevalence was 3.9% and similar in 206 STD patients, 127 dermatology patients, and 100 blood donors. No association with HIV or syphilis was observed. Despite high prevalence of STDs, sexual transmission does not appear to significantly contribute to HCV transmission in Malawi.

Comparison of hepatitis C viral loads in patients with or without human immunodeficiency virus

A better understanding of how human immunodeficiency virus (HIV) coinfection affects the course of hepatitis C virus (HCV) infection is required to select patients with HIV who would benefit from current HCV therapy. Between June 1996 and March 2000, HCV RNA levels were quantified for 1,279 patients at the Louisiana State University Health Sciences Center; 28 of these patients were coinfected with HIV. HCV loads were quantified by the Bayer branched-DNA assay with a lower limit of detection of 0.2 Meq/ml. We compared the median HCV RNA levels of for patients coinfected with HIV and HCV and patients infected only with HCV who were in the same age range (23 to 55 years). The median HCV load for the 28 patients coinfected with HCV and HIV (17.8 Meq/ml) was significantly greater (P < 0.05) than that for similarly aged patients infected only with HCV (6.1 Meq/ml). The HCV load did not correlate with age or sex for either group of patients. A significant (R = -0.4; P < 0.05) negative correlation was observed between HCV load and CD4 count in the coinfected group, for whom the CD4 counts at the time of HCV load analysis ranged from 6 to 1,773/mm(3). The increased HCV load in patients coinfected with HCV and HIV compared to that in patients infected only with HCV and the inverse relationship of the HCV load to the CD4 count indicate that immunosuppression results in decreased control of HCV replication. In addition, we report significantly higher HCV loads among coinfected African Americans than Caucasians.

Mortality among human immunodeficiency virus-infected patients with cirrhosis or hepatocellular carcinoma due to hepatitis C virus in French Departments of Internal Medicine/Infectious Diseases, in 1995 and 1997

Several studies have suggested that the progression of hepatitis C virus (HCV) infection is more severe in patients infected by the human immunodeficiency virus (HIV). Two national retrospective multicenter cohort surveys were performed in France that included 17,487 HIV-infected patients during 1995 and 26,497 during 1997. The following data was evaluated: total number of deaths; number of deaths linked to AIDS, cirrhosis, or hepatocellular carcinoma (HCC); and number of deaths related to other (non-HCV--linked) causes. In 1995, the causes of death were as follows: AIDS, 1307 (7.47%); cirrhosis or HCC, 21 (0.12%); and other (non-HCV--linked) causes, 99 (0.56%). In 1997, the causes of deaths were as follows: AIDS, 459 (1.73%); cirrhosis or HCC 36 (0.13%); and other (non-HCV--linked) causes, 48 (0.18%). Comparative results between the 1995 and 1997 surveys showed a dramatic decrease in AIDS-related mortality rates (7.47% vs. 1.73%; P<.001) but not in HCV-related mortality rates (0.06% vs. 0.07%; P=.79). In France, despite the high prevalence of HCV infection in HIV-positive patients, the mortality rate in 1995 and 1997 caused by HCV-related cirrhosis or HCC was low.

High incidence of hepatitis B infections among chronic hepatitis cases of unknown aetiology

BACKGROUND/AIMS

In approximately 5% of chronic liver disease cases, no aetiology can be identified. We selected sera from 50 patients with chronic hepatitis of unknown aetiology who were enrolled in this follow-up study whose aim is to gain insight into the possible role of viruses and to define potential clinical outcomes.

METHODS

Patients' sera were screened with highly sensitive polymerase chain reaction assays for hepatitis B (HBV), C, D, and G viruses and TT virus. Sera were also retested for antibodies against the core antigen of HBV.

RESULTS

Surprisingly, HBV DNA was detected in both serum and liver in 15/50 (30%) patients. Immunostaining for HBV antigens on biopsies from patients positive for HBV DNA showed HBcAg and/or HBsAg expression at low levels in 9/15 samples. Eleven of the fifteen patients were anti-HBc positive. With one exception, all patients carried HBV genomes at low levels (10(4) copies/ml or less). Histological signs of chronic liver disease were observed in all patients.

CONCLUSION

Unrecognised HBV infections may account for a high proportion of chronic hepatitis cases of unknown aetiology. Improved HBV detection tests, which appear mandatory for the diagnosis and management of non-A non-E hepatitis as well as for improved safety of transfusions and transplantations are needed.

Hepatitis C virus seroprevalence and risk factors among patients with HIV infection

The objective of this study was to evaluate the prevalence and risk factors associated with HCV infection in a group of HIV seropositive patients. We analyzed the medical records of 1,457 patients. All patients were tested for HCV infection by third generation ELISA. Whenever possible, a sample of the positive patients was also tested for HCV by PCR. HCV positive patients were analyzed according to their risk factors for both infections. The prevalence of anti-HCV positive patients was 17.7% (258 patients). Eighty-two (82) of these patients were also tested by PCR and 81 were positive for HCV virus (98%). One hundred fifty-one (58.5%) were intravenous drug users (IDU); 42 (16.3%) were sexual partners of HIV patients; 23 (8.9%) were homosexual males; 12 (4.7%) had received blood transfusion; 61 (17.5%) had promiscuous sexual habits; 14 (5.4%) denied any risk factor; 12 (4.7%) were sexual partners of IDU. Two hundred four patients mentioned only one risk factor. Among them, 28 (10.9%) were sexual partners of HIV-positive patients. Although intravenous drug use was the most important risk factor for co-infection, sexual transmission seemed to contribute to the high HCV seroprevalence in this group of patients.

Immunologic dynamics in hemophiliac patients infected with hepatitis C virus and human immunodeficiency virus: influence of antiretroviral therapy

Infection with hepatitis C virus (HCV) or human immunodeficiency virus (HIV) or both is common in hemophiliac patients due to putative transmission through clotting factor concentrates. Recently, highly active antiretroviral therapy (HAART) has been found to markedly improve viremia and immunologic parameters in patients infected with HIV. This report considers interactions between these viral infections, the immune system, and antiretroviral therapy. A total of 130 male hemophiliac patients were grouped according to type of viremia (HCV, HIV, both, or neither). Along with 30 healthy men age-matched to viremic patients, these groups were compared with respect to viral load and immunologic parameters. Thirty-five patients treated as above for HIV were serially followed up. HCV infection was associated with reduced peripheral B-cell and CD4+-cell counts and with increased serum IgG and IgM levels, whereas HIV infection was associated with reduced peripheral CD4+-cell counts and increased serum IgG and IgA levels. In patients with both viruses, HCV and HIV RNA load correlated inversely with peripheral B-cell and CD4+-cell counts, respectively. HAART reduced levels of both viruses in the blood. Of the 25 patients with both viruses, HAART eliminated HCV in 2. In conclusion, immunologic dynamics differed between hemophiliac patients infected with HCV, HIV, or both. The relative dynamics of HCV viral load, peripheral B-cell count, and serum IgM level were similar to those of HIV viral load, CD4+-cell count, and serum IgA.

Immunologic dynamics in hemophiliac patients infected with hepatitis C virus and human immunodeficiency virus: influence of antiretroviral therapy

Infection with hepatitis C virus (HCV) or human immunodeficiency virus (HIV) or both is common in hemophiliac patients due to putative transmission through clotting factor concentrates. Recently, highly active antiretroviral therapy (HAART) has been found to markedly improve viremia and immunologic parameters in patients infected with HIV. This report considers interactions between these viral infections, the immune system, and antiretroviral therapy. A total of 130 male hemophiliac patients were grouped according to type of viremia (HCV, HIV, both, or neither). Along with 30 healthy men age-matched to viremic patients, these groups were compared with respect to viral load and immunologic parameters. Thirty-five patients treated as above for HIV were serially followed up. HCV infection was associated with reduced peripheral B-cell and CD4+-cell counts and with increased serum IgG and IgM levels, whereas HIV infection was associated with reduced peripheral CD4+-cell counts and increased serum IgG and IgA levels. In patients with both viruses, HCV and HIV RNA load correlated inversely with peripheral B-cell and CD4+-cell counts, respectively. HAART reduced levels of both viruses in the blood. Of the 25 patients with both viruses, HAART eliminated HCV in 2. In conclusion, immunologic dynamics differed between hemophiliac patients infected with HCV, HIV, or both. The relative dynamics of HCV viral load, peripheral B-cell count, and serum IgM level were similar to those of HIV viral load, CD4+-cell count, and serum IgA.

Serological pattern "anti-HBc alone": report on a workshop

In areas with low hepatitis B virus (HBV) endemicity such as most parts of Europe and the United States "anti-HBc alone" is found in 10-20% of all individuals with HBV markers, i.e., 1-4% of the population. In about 10% of these individuals HBV DNA is detected by PCR, the proportions varying greatly depending on the population studied, being highest in individuals coinfected with hepatitis C virus (HCV) (above 35%) and HIV (above 85%). A small proportion of individuals with "anti-HBc alone" are in the window phase of an HBV infection or in a stage of late HBV immunity. For the large proportion of these individuals this is not the case and they are thought to have an unresolved HBV-infection or a chronic infection in a late or "low grade" productive state. Currently, limited studies have been performed concerning the clinical aspects of individuals with "anti-HBc alone" and suspected chronic HBV infection. The majority of these individuals seem to be healthy. Some chronic carriers with "anti-HBc alone," however, do present signs of chronic hepatitis. Individuals with "anti-HBc alone" are potentially infectious. This is exemplified by a few case reports of HBV transmission to sexual contacts, perinatal transmission between mother and newborns and in blood recipients. Recommendations are given in relation to both the diagnostic and therapeutic procedures in the individuals with "anti-HBc alone" and in the blood banking and transplantation services.

Coinfection with HIV and HCV: more questions than answers?

Chronic infection with the hepatitis C virus (HCV) is a major public health threat in the United States and worldwide. By sharing some routes of transmission, persons infected with the human immunodeficiency virus (HIV) are at risk for coinfection with HCV As a result, hepatic cirrhosis, end-stage liver disease, and hepatocellular carcinoma due to chronic infection with HCV are important causes of both morbidity and mortality in coinfected patients. The advent of highly active antiretroviral therapy improved the management of patients with HIV, leading to decreased morbidity and better survival. As patients infected with HIV live longer, their risk of long-term sequelae from chronic HCV increases. Coinfection with HIV may be associated with rapid progression of chronic HCV. In contrast, the effect of HCV on the natural history of HIV is less clear. Data regarding treatment of HCV in HIV-coinfected patients are limited.

Hepatitis C virus/human immunodeficiency virus coinfection: clinical management issues

The use of highly active antiretroviral therapy (HAART) has extended the healthy lifespan of patients infected with human immunodeficiency virus (HIV); deaths among people with AIDS declined for the first time in 1996, after the institution of this therapeutic approach. As the life expectancy of HIV-infected patients increases, greater attention will need to be focused on the recognition and management of potentially severe concurrent illnesses that may increase their mid- to long-range morbidity and mortality. The incidence of infection by hepatitis C virus (HCV) is increased among patients with HIV disease, reflecting shared epidemiological risks. HCV not only may have an impact on the health status of HIV-infected patients but also may decrease their quality of life and increase their health care costs. Although clinicians have been reluctant to treat viral hepatitis C in the HIV-infected population, this therapeutic nihilism is unwarranted. The majority of studies have concluded that treatment of hepatitis C in HIV-infected patients results in an initial efficacy and long-term response similar to those in the HIV-seronegative population. Furthermore, treatment of HCV infection in HCV/HIV-coinfected patients may improve tolerance for antiretroviral medications. Physicians caring for patients with HIV infection require up-to-date information to make rational decisions regarding HCV coinfection to ensure that morbidity and mortality are minimized and that quality of life and medical care costs are optimized.

HIV and Hepatitis Virus Infection

As the life expectancy of patients with HIV infection increases, greater attention will need to be focused on concurrent illnesses, such as viral hepatitis, that may increase mid- to long-range morbidity and mortality. The incidence of viral hepatitis is increased in patients with HIV disease, reflecting the epidemiologic risks that these two conditions share. Coinfection with HIV seems to adversely affect the natural history of hepatitis C but may actually reduce the hepatic damage associated with hepatitis B. Immunosuppression due to HIV does not seem to significantly affect hepatitis A, E, or G. Clinicians have been reluctant to treat viral hepatitis in the HIV-infected population, but this therapeutic nihilism is unwarranted. Most studies have concluded that the treatment of hepatitis C in HIV-infected patients results in an initial efficacy and a long-term response similar to those seen in the HIV-seronegative population. Although the efficacy of interferon is reduced against hepatitis B, some nucleoside analogues are effective.

Expression of regeneration and tolerance factor correlates directly with human immunodeficiency virus infection and inversely with hepatitis C virus infection

Hepatitis C virus (HCV) and human immunodeficiency virus (HIV) cause two of the most prevalent debilitating viral infections. HIV appears to induce a skewing toward a Th2 response, while in HCV infection a Th1 response appears to dominate. Regeneration and tolerance factor (RTF) may participate in driving or sustaining a Th2 cytokine response. The expression of RTF on CD3(+) T cells of HIV-seropositive (HIV(+)) individuals is increased. The purpose of this study was to compare the expression of RTF during HIV infections with that during HCV infections. Three-color flow-cytometric analysis of peripheral blood collected from HIV(+) HCV-seropositive (HCV(+)), HIV- and HCV-seropositive (HIV(+) HCV(+)), and HIV- and HCV-seronegative (HIV(-) HCV(-)) individuals was performed. Levels of RTF expression on T-lymphocyte subsets from these groups were compared, as were levels of RTF expression on activated T cells expressing CD38 and HLA-DR, to determine the relationship of RTF expression to these infections. We demonstrated that the expression of RTF on surfaces of T cells from HIV(+) individuals is upregulated and that its expression on T cells from HCV(+) individuals is downregulated. A twofold increase in the mean channel fluorescence of RTF on CD3(+) T cells was seen in both HIV(+) and HIV(+) HCV(+) individuals compared to HIV(-) HCV(-) individuals. HCV(+) individuals had lower levels of RTF expression than HIV(-) HCV(-) individuals (P < 0.005 for CD4(+); P < 0.0005 for CD8(+)). In terms of percentages of T cells expressing RTF, the groups were ranked as follows: HIV(+) > HIV(+) HCV(+) > HIV(-) HCV(-) > HCV(+). The results indicate that RTF expression correlates with HIV-associated immune activation and may be associated with Th2-type responses.

Prevalence of hepatitis B and C in the sera of patients with HIV infection in São Paulo, Brazil

The objective of this study was to evaluate the prevalence of hepatitis B and C viruses in a group of HIV infected patients, followed at a single institution since 1996. 1,693 HIV positive patients (1,162 male, 531 female) were tested for HBV infection. Virological markers for HBV included HBsAg and total anti-HBc by ELISA. 1,457 patients (1,009 male, 448 female) were tested for HCV infection. Detection of HCV antibodies was carried out by ELISA. A sample of HCV antibody positive patients was tested for HCV by PCR to confirm infection. Of 1,693 patients tested for HBV, 654 (38.6%) and 96 (5.7%) were anti-HBc and HBsAg positive, respectively. Of 1, 457 patients tested for HCV, 258 (17.7%) were anti-HCV positive. 82 of these patients were also tested by PCR and 81 were positive (98%). Of 1,411 patients tested for HBV and HCV 26 (1.8%) were positive for both viruses.

Current Views on Hepatitis C Virus Infection

Hepatitis C virus infection affects more than 4 million people in the United States and is a leading cause of liver failure necessitating transplantation. Effective combination therapies are now available for subgroups of patients at risk for progression to cirrhosis. The benefits of therapy in immunosuppressed hosts, such as HIV-infected patients and liver transplant recipients, are less well established.

Diagnostic tests for hepatitis C

Two categories of virological assays are in practice used for the diagnosis and management of hepatitis C virus (HCV) infection, including serological and molecular biology-based assays. Serological assays include: screening tests based on enzyme immunoassays (EIAs); supplemental "analytical" assays based on immunoblot testing; and serological assays detecting genotype-specific antibodies for the serological determination of HCV genotype, so-called "serotyping" assays. Molecular assays include: qualitative assays, detecting HCV RNA in body fluids; quantitative assays measuring HCV viral load, a parameter that estimates the level of HCV replication in the liver; and tests analyzing the sequence of HCV genomes (genotyping assays).

Meningococcemia in a patient coinfected with hepatitis C virus and HIV

We describe the first reported case of meningococcemia in a patient coinfected with hepatitis C virus and HIV. Hypocomplementemia secondary to hepatic dysfunction may have enhanced the patient's susceptibility to meningococcal infection.

Extrahepatic manifestations associated with hepatitis C virus infection. A prospective multicenter study of 321 patients. The GERMIVIC. Groupe d'Etude et de Recherche en Medecine Interne et Maladies Infectieuses sur le Virus de l'Hepatite C

From January 1996 to January 1997, 321 patients with an average age of 46 +/- 16 years and chronically infected with hepatitis C virus (HCV) were prospectively enrolled in a study designed to determine the prevalence of extrahepatic manifestations associated with HCV infection in a large cohort of HCV patients, to identify associations between clinical and biologic manifestations, and to compare the results obtained in human immunodeficiency virus (HIV)-positive versus HIV-negative subsets. In a cross-sectional study, clinical extrahepatic manifestations, viral coinfections with HIV and/or hepatitis B virus, connective tissue diseases, and a wide panel of autoantibodies were assessed. Thirty-eight percent (122/321) of patients presented at least 1 clinical extrahepatic manifestation including arthralgia (60/321, 19%), skin manifestations (55/321, 17%), xerostomia (40/321, 12%), xerophthalmia (32/321, 10%), and sensory neuropathy (28/321, 9%). Main biologic abnormalities were mixed cryoglobulins (110/196, 56%), thrombocytopenia (50/291, 17%), and the presence of the following autoantibodies: antinuclear (123/302, 41%), rheumatoid factor (107/280, 38%), anticardiolipin (79/298, 27%), antithyroglobulin (36/287, 13%) and antismooth muscle cell (27/288, 9%). At least 1 autoantibody was present in 210/302 (70%) of sera. By multivariate logistic regression analysis, 4 parameters were significantly associated with cryoglobulin positivity: systemic vasculitis (p = 0.01, odds ratio OR[ = 17.3), HIV positivity (p = 0.0006, OR = 10.2), rheumatoid factor positivity (p = 0.01, OR = 2.8), and sicca syndrome (p = 0.03, OR = 0.27). A definite connective tissue disease was noted in 44 patients (14%), mainly symptomatic mixed cryoglobulinemia and systemic vasculitis, HIV coinfection (23%) was associated with 3 parameters: anticardiolipin (p = 0.003, OR = 4.18), thrombocytopenia (p = 0.01, OR = 3.56), and arthralgia or myalgia (p = 0.017, OR = 0.23). HIV-positive patients presented more severe histologic lesions (p = 0.0004). Extrahepatic clinical manifestations in HCV patients involve primarily the skin and joints. The most frequent immunologic abnormalities include mixed cryoglobulins, rheumatoid factor, antinuclear, anticardiolipin, and antithyroglobulin antibodies. Cryoglobulin positivity is associated with systemic vasculitis and rheumatoid factor and HIV positivity. HIV coinfection is associated with arthralgia or myalgia, anticardiolipin antibodies, and thrombocytopenia.

[Interactions between the human immunodeficiency virus and hepatitis C virus]

INTRODUCTION

Prevalence of hepatitis C virus (HCV) infection in human immunodeficiency virus (HIV)-infected subjects is around 9%, varying according to the mode of contamination. Reciprocal interactions between the two viruses have to be evaluated.

CURRENT KNOWLEDGE AND KEY POINTS

HCV infection is usually associated with chronic hepatitis and detectable viremia in HIV-infected patients. HIV infection enhances HCV replication, leading to more severe liver lesions and to a more rapid occurrence of cirrhosis. This underlines the need for both early diagnosis and therapy in order to avoid severe evolution of the liver disease.

FUTURE PROSPECTS AND PROJECTS

Even though the rate of long-term responses to interferon alpha is low, improvement may be expected from combined therapies, especially with combination including ribavirin. The impact of both antiretroviral triple therapy and accompanying immune restoration on natural history and treatment of HCV infection has to be assessed, as the above mentioned consensual conclusions may be modified in a near future.

HIV-1 genetic subtype A/B recombinant strain causing an explosive epidemic in injecting drug users in Kaliningrad

OBJECTIVES

To investigate the molecular epidemiology and genetic structure of the virus strain(s) causing an outbreak of HIV-1 infection in the Kaliningrad province of the Russian Federation and to investigate the relationship of this outbreak to some other emerging HIV-1 epidemics in the countries of the former Soviet Union.

DESIGN

A molecular epidemiological investigation was conducted in the city of Kaliningrad amongst individuals recently diagnosed as HIV-1-positive. Samples were also collected from neighbouring Lithuania and from the Ukraine.

METHODS

Incident and population data was collected from official health statistics in Kaliningrad. A standardized questionnaire was administered to newly diagnosed individuals to assess risk factors for HIV-1 infection. For genotyping, two regions of the virus (env C2-V3 and gag NCp7) were directly sequenced.

RESULTS

The number of newly diagnosed individuals testing seropositive for HIV-1 infection in Kaliningrad rose from less than one per month to more than 100 per month during the period of July-October 1996. A total of 1335 new infections were identified between 1 July 1996 and 30 June 1997. The main reported risk factor for HIV-1 infection (80%) was injecting drug use, in particular with a locally produced opiate. Sequence analysis of patient viruses in Kaliningrad (n = 50) showed that the epidemic was caused by a highly homogenous HIV-1 strain, recombinant between the genetic subtypes A and B. Comparison with subtype A strains prevalent amongst injecting drug users (IDU) in the Ukraine showed that one of these strains was the direct subtype A parent of the epidemic A/B recombinant strain in Kaliningrad.

CONCLUSIONS

The HIV-1 epidemic in Kaliningrad probably started from a single source, with rapid spread of the virus through the IDU population. The origin of the epidemic strain is a recombination event occurring between the subtype A strain virus prevalent among IDU in some southern CIS countries, and a subtype B strain of unknown origin.

Review article: interferon and hepatitis C--factors predicting therapeutic outcome

Hepatitis C chronically infects approximately 1.5% of Americans and is the most common clinical problem facing hepatologists. Since the virus was initially described in 1989, development of an effective therapy has been challenging. Although several different therapeutic agents have been used, no therapy has been shown to reliably eradicate the virus. Interferon-alpha, a cytokine with immunostimulatory and anti-viral properties, has become the therapy of choice for patients with chronic hepatitis C infection. Trials assessing the efficacy of interferon-alpha have characterized host and viral factors predictive of responses to treatment. A thorough understanding of these predictive factors is requisite to providing cost-effective therapeutic decisions for the patient with chronic hepatitis C infection.

Hepatobiliary and pancreatic infections in AIDS: Part one

Infections of the liver and biliary tract are common during the course of AIDS. A variety of viral, bacterial, fungal, and other opportunistic infections can present with hepatobiliary involvement as either the primary site of infection or secondary to a disseminated process. Coinfection with hepatitis B and C are particularly common due to the shared means of transmission of these viruses with HIV. The typical presenting features of hepatobiliary infections are right upper quadrant (RUQ) pain and abnormal liver function tests. Initial evaluation should include an RUQ ultrasonogram, which will usually identify abnormalities in the biliary tract and may demonstrate some parenchymal abnormalities as well. A liver biopsy is necessary to determine the etiology of focal hepatic lesions or opportunistic infections within hepatic parenchyma when other less invasive tests are negative or inconclusive. Special stains and culture techniques are required to identify specific organisms in the biopsy specimen. HIV-related biliary disorders include acalculous cholecystitis, which is a potentially serious condition requiring prompt recognition and gallbladder decompression. AIDS-cholangiopathy is a form of cholangitis involving the intra- and/or extrahepatic biliary tree. Endoscopic retrograde cholangio-pancreatography (ERCP) is the test of choice, demonstrating the stricturing, dilatation, and beading of bile ducts seen in this condition. Endoscopic sphincterotomy of the papilla of Vater may provide symptomatic relief for patients with papillary stenosis. Opportunistic infections of the pancreas have been reported. Evaluation should include a computerized tomogram of the abdomen and possible pancreatic tissue aspiration or biopsy. Management of pancreatitis is supportive.