Hepatitis C virus-associated hepatitis following treatment of HIV-infected patients with HIV protease inhibitors: an immune restoration disease?

Immune reconstitution inflammatory syndrome (IRIS): review of common infectious manifestations and treatment options

The immune reconstitution inflammatory syndrome (IRIS) in HIV-infected patients initiating antiretroviral therapy (ART) results from restored immunity to specific infectious or non-infectious antigens. A paradoxical clinical worsening of a known condition or the appearance of a new condition after initiating therapy characterizes the syndrome. Potential mechanisms for the syndrome include a partial recovery of the immune system or exuberant host immunological responses to antigenic stimuli. The overall incidence of IRIS is unknown, but is dependent on the population studied and its underlying opportunistic infectious burden. The infectious pathogens most frequently implicated in the syndrome are mycobacteria, varicella zoster, herpesviruses, and cytomegalovirus (CMV). No single treatment option exists and depends on the underlying infectious agent and its clinical presentation. Prospective cohort studies addressing the optimal screening and treatment of opportunistic infections in patients eligible for ART are currently being conducted. These studies will provide evidence for the development of treatment guidelines in order to reduce the burden of IRIS. We review the available literature on the pathogenesis and epidemiology of IRIS, and present treatment options for the more common infectious manifestations of this diverse syndrome and for manifestations associated with a high morbidity.

Low incidence of severe liver events in HIV patients with and without hepatitis C or B coinfection receiving lopinavir/ritonavir

OBJECTIVES

To analyze the incidence of severe liver events in HIV patients treated with lopinavir/ritonavir and the role of coinfection in the development of this toxicity.

METHOD

This was a retrospective, multicenter, cohort study of all HIV-positive patients who started a regimen of HAART that included lopinavir/ritonavir (LPV/r). The main outcome variable was the emergence of a severe liver event, defined as decompensation of pre-existing chronic liver disease and grade 3-4 hypertransaminasemia (HT), that is, plasma AST or ALT values >5 times above the upper limit of normality, if baseline levels were normal, or >3.5 times the baseline values when they were abnormal.

RESULTS

388 HIV-infected patients were included, with a median follow-up of 25.6 months. Coinfection with HCV was present in 61% of the patients and with HBV in 6.7%. There were 6 cases of severe liver events, all involving patients who were coinfected with HCV and all within the first 6 months. This represents 0.72 events per 100 patient-years (95% confidence interval [CI] 0.36-2.98) and 1.21 events per 100 patient-years (95% CI 0.60-5.86) in coinfected patients. The only factors associated with severe liver events at 6 months were baseline HT and HCV coinfection.

CONCLUSION

The incidence of severe hepatic events in HIV-positive patients receiving a HAART regimen including LPV/r was very low, even in coinfected patients. HCV coinfection and baseline HT were the only factors associated with severe liver events. LPV/r can be considered a safe and well-tolerated option in HIV patients with hepatotropic virus coinfections.

Hepatitis C in HIV-positive patients--treatment and liver disease outcomes

Many human immunodeficiency virus (HIV) infected persons are coinfected with hepatitis C virus (HCV) and with the use of highly active antiretroviral therapy, liver disease from HCV has become an important cause of morbidity and mortality. The current guidelines recommend that human immunodeficiency virus and HCV coinfected patients be evaluated and treated for HCV if there are no major contraindications to treatment. Coinfected patients treated with pegylated interferon-a and ribavirin have sustained virologic responses (SVRs) of 27% to 40% which for a variety of reasons are lower than those reported in HCV mono-infected patients. Understanding that most patients will not achieve SVRs, strategies to evaluate for the role of maintenance interferon in delaying complications of liver disease are being evaluated. In patients who have failed prior treatment, cannot tolerate treatment, or who have contraindications to HCV treatment, the use of highly active antiretroviral therapy with careful monitoring for hepatotoxicity and aggressive counseling on alcohol and substance abuse may slow down fibrosis progression. As the data on liver transplantation in coinfected patients accumulate, patients with end stage liver disease should be referred early for evaluation in a transplant center. As new drugs for HCV are being developed, it will be of utmost importance to include coinfected patients earlier in the process on new drug trials and therapeutic strategies.

Antiretroviral medication considerations for individuals coinfected with HIV and hepatitis C virus

There is great need to treat HIV/hepatitis C virus (HCV)-coinfected individuals with both antiretroviral and anti-HCV pharmacotherapy. However, treatment for HIV may lead to hepatotoxicity, and there are potential interactions and synergistic effects between antiretrovirals and anti-HCV medications. The ideal antiretroviral therapy options for coinfected patients, in the setting of anti-HCV treatment, are unclear and present important challenges to clinicians. We review the current data on the use of antiretrovirals in HIV/HCV-coinfected patients and offer evidence-based recommendations on optimal selection and dosing of antiretroviral agents for this population.

Evidence base for using corticosteroids to treat HIV-associated immune reconstitution syndrome

Most of the evidence supporting the use of corticosteroids (steroids) for immune reconstitution syndrome (IRS) comes from case reports or retrospective series and is of low quality. However, when steroids are used, they have usually been associated with clinical improvement or resolution of IRS. Except in the case of hepatitis B- or C-associated IRS, there have been no reports of worsening of the IRS or adverse outcome due to steroid use. After ruling out other conditions which can mimic IRS, clinicians should strongly consider steroids when managing IRS associated with mycobacterial or fungal pathogens when there is severe disease, or when other measures have failed.

HIV-related liver disease: infections versus drugs

HIV-infected individuals have myriad causes of hepatotoxicity that range from mild hepatitis to significant liver failure with its associated morbidity and mortality, especially in the setting of chronic viral hepatitis (HCV and HBV). Immune restoration by HAART therapy can contribute liver-related toxicity in HIV-coinfected patients. Clinicians need to be aware of this problem and individualize management in this challenging clinical scenario. Avoidance of potentially hepatotoxic agents or close monitoring during treatment of HIV may prevent liver failure in patients who have HIV. Furthermore, vaccination against hepatitis A virus and HBV in nonimmune HIV individuals may prevent acquisition of hepatitis A virus and HBV infections in patients who have HIV. Finally, treatment of HIV, and, if appropriate, treatment of those who are coinfected with HCV and HBV with close monitoring, may improve the outcome of patients who have HIV and are at risk fo r significant hepatotoxicity during treatment from immune restoration or hypersensitivity reactions.

Hepatotoxicity of antiretrovirals: incidence, mechanisms and management

One of the toxicities linked to the use of antiretrovirals is the elevation of transaminases. Liver toxicity is a cause of morbidity, mortality, and treatment discontinuation in HIV-infected patients. While several antiretrovirals have been reported to cause fatal acute hepatitis, they most often cause asymptomatic elevations of transaminases. Liver toxicity is more frequent among subjects with chronic hepatitis C and/or B. The incidence of drug-induced liver toxicity is not well known for most antiretrovirals. The contribution of each particular drug to the development of hepatotoxicity in a HAART regimen is difficult to determine. Possible pathogenic mechanisms involved in hepatotoxicity are multiple, including direct drug toxicity, immune reconstitution in the presence of HCV and/or HBV co-infections, hypersensitivity reactions with liver involvement, and mitochondrial toxicity. Other pathogenic pathways may be involved, such as insulin resistance caused by several antiretrovirals, which may contribute to the development of steatohepatitis. The management of liver toxicity is based mainly on its clinical impact, severity and pathogenic mechanism.

Natural history and predictors of severity of chronic hepatitis C virus (HCV) and human immunodeficiency virus (HIV) co-infection

Co-infection by the hepatitis C virus (HCV) is observed in up to 30% of HIV-infected individuals. In studies conducted in the 'pre-HAART era', the late consequences of HCV-related chronic liver disease were overshadowed by extra-hepatic causes of deaths, related to severe immune deficiency, and the impact of HCV infection on mortality of HIV-infected patients was low. While the development of HAART has resulted in a significant decrease in morbidity and mortality amongst HIV-infected patients, this clear benefit allowed the expression of liver-related complications associated with HCV chronic infection. The impact of HCV on HIV remains debated but HIV infection significantly modifies the natural history of HCV infection. HIV infection increases levels of HCV viraemia by 2- to 8-fold, resulting in a significant decrease in spontaneous recovery of acute hepatitis. HIV co-infection also worsens the histological course of HCV infection by increasing and accelerating the risk of cirrhosis or leading to rare but lethal fibrosing cholestatic hepatitis. Liver disease is now one of the leading causes of morbidity and mortality in co-infected patients, even if HAART and especially protease inhibitors, may decrease the severity of the liver disease and the liver-related mortality. Several non-exclusive pathogenic processes explain the increasing rate of liver complications associated with HCV-related liver disease.

HBV plus HCV, HCV plus HIV, HBV plus HIV

Coinfection of hepatitis C virus (HCV), hepatitis B virus (HBV), and HIV is common due to shared modes of transmission. These coinfections accelerate the course of chronic liver disease and facilitate progression to cirrhosis and hepatocellular carcinoma. The viral interactions between these viruses are complex, and their treatment may be challenging for clinicians.

Liver enzyme elevation in hepatitis C virus (HCV)-HIV-coinfected patients prior to and after initiating HAART: role of HCV genotypes

Transaminase elevation is frequently seen in hepatitis C virus (HCV)-HIV-coinfected patients receiving antiretroviral therapy (ART), representing an increase in the immune response against HCV and being one of the mechanisms proposed to be involved. There is a report claiming that HCV genotype 3 is an independent risk factor. Our objectives were to assess the incidence of liver toxicity in an HIV-HCV-coinfected population with relatively preserved cellular immunity, and the role of HCV genotypes in the elevation of liver enzymes, both at baseline and after initiating ART. All HIV(+) patients with positive anti-HCV serology and CD4(+) cell counts above 100/mm(3) who began triple ART were identified, and their HCV-RNA levels and HCV genotype were determined. Liver enzymes were determined at baseline and bimonthly during follow-up. Of anti-HCV patients 147 were included, 128 (87.1%) of whom had detectable plasma HCV-RNA. HCV-1 and HCV-4 genotypes were found to confer an increased probability of having at baseline transaminases within normal limits over the other genotypes. Severe transaminase elevations (grades 3 and 4) occurred in 5/124 patients (4.0%), all with high pre-HAART ALT and positive HCV-RNA levels. Multivariate analysis showed that patients with genotype HCV-3 had a 3.27 times higher risk of developing HAART-related transaminase elevations of any grade. In conclusion, subjects with the HCV-1 genotype more often had transaminases within normal limits at baseline. The incidence of severe transaminase elevation after initiating ART was very low (4%) in this HIV(+) population with relatively preserved cellular immunity. HCV genotype 3 was identified as a risk factor for the development of transaminase elevation of any grade.

Clinical outcomes of first antiretroviral regimen in HIV/hepatitis C virus co-infection

OBJECTIVES

Despite the benefits of HAART, initiation of antiretroviral therapy in HIV-HCV co-infected patients is often delayed as a consequence of patient and physician concern pertaining to liver toxicity. It is unclear whether this is justified.

METHODS

We retrospectively evaluated treatment duration and outcome in 186 patients initiating a first HAART regimen.

RESULTS

Despite frequent HIV RNA suppression and CD4 T-cell increase following initiation of HAART, the median duration of therapy was only 8 months. Therapy was discontinued primarily for gastrointestinal intolerance (26%), poor adherence (19%), neurocognitive side effects (13%), and substance abuse (6%). Regimes were changed to reduce pill burden and/or frequency of dosing as well (11%). Only six (4%) subjects interrupted therapy as a result of clinically apparent liver toxicity. None were on low dose ritonavir-containing therapy. In those subjects remaining on HAART for at least 12 months, the median ALT level increased marginally from a baseline of 44 IU/mL to 56 IU/mL. The median AST was 44 IU/mL at baseline and at month 12.

CONCLUSIONS

These results support our contention that regimen potency, durability, and extrahepatic side effect profile should remain the paramount considerations related to the selection of HAART regimen in HIV-HCV co-infection.

Is there evidence for an increase in the death rate from liver-related disease in patients with HIV?

BACKGROUND

Increases in deaths due to liver-related disease (LRD) among HIV-infected individuals have been reported although the influence of combination antiretroviral therapy (cART) on LRD is controversial.

AIMS

To determine changes over time in the death rate from LRD and if longer exposure to cART was associated with an increased death rate from LRD in 10 937 patients from EuroSIDA, an observational longitudinal cohort study.

RESULTS

A total of 184 (1.7%) died from LRD during 52 236 person-years of follow-up (PYFU). The death rate from LRD declined from 6.9 per 1000 PYFU before 1995 [95% confidence interval (CI), 3.9-9.9] to 2.6 at/after 2004 (95% CI, 1.6-4.0). When the current CD4 cell count and other factors were taken into account, there was a 13% increase in the death rate from LRD per year (95% CI, 5-20%, P = 0.0008). In patients who had started cART, there was a 12% increase in the death rate from LRD per additional year exposure to cART (95% CI, 4-20%, P = 0.022) after adjustment for current CD4 cell count and other factors.

CONCLUSIONS

Death rates from LRD appeared to decrease across Europe. However after adjustment for the current CD4 cell count, and therefore increases in CD4 cell counts in patients taking cART, there was a significant increase over time in death rates from LRD. In patients with similar CD4 cell counts, longer exposure to cART was associated with an increased death rate from LRD. This may be due to direct liver toxicity of antiretrovirals, progression of liver disease due to hepatitis B virus or hepatitis C virus over time as patients survive longer, or some other factor.

Progression of HIV infection in the post-HAART era among a cohort of HIV+ Greek haemophilia patients

AIM

The study aims to describe the course of HIV-1 infection in the pre- and post-HAART period in a cohort of HIV+ haemophilia patients followed up for up to 21 years.

METHODS

The cohort includes 158 haemophilic men with known seroconversion dates followed up prospectively for a median time of 12 and 5.7 years in the pre- (1980-96) and post-HAART period (1997-2003), respectively.

RESULTS

The risk of developing AIDS was lowered by 56% in the post- as compared to the pre-HAART period. Of the 158 patients 69 developed AIDS in the pre-HAART period while of the 59 subjects still alive and AIDS free on 1/1/1997 six developed AIDS. The rate of PCP (12.0 cases per 1000 person-years) and NHL (5.4 cases per 1000 person-years), the most common causes of AIDS diagnosis in the pre-HAART era, were remarkably reduced in the post-HAART era (both rates: 2.8 cases per 1000 person-years). On the contrary, the corresponding risk for non-AIDS deaths was fourfold increased in the post-HAART period. Of the 38 non-AIDS related deaths in both periods, 13 occurred post-HAART. The predominant cause of non-AIDS mortality in both periods was end-stage liver disease (ESLD) (7 pre- and 4 post-HAART). The rate of non-AIDS related cancers was also increased during the post-HAART period.

CONCLUSION

In this haemophilia cohort the risk of AIDS has substantially reduced in the post-HAART period, but the rate of non-AIDS mortality tended to increase. Among haemophilia subjects, due to the high rates of HCV/HIV coinfection, ESLD, the predominant cause of non-AIDS mortality, will become an increasingly important clinical problem.

HIV and liver diseases: recent clinical advances

Because the life expectancy of patients infected with HIV has been prolonged, liver diseases have assumed far greater importance as a cause of morbidity and mortality in these patients. Given the shared risks of transmission, patients who have HIV often are coinfected with hepatotrophic viruses such as hepatitis C and hepatitis B. Further, antiretroviral therapy (ART) used by patients who have HIV is often hepatotoxic, contributing to liver damage. With increasing immunosuppression caused by AIDS, patients who have HIV have to deal with these issues and the increased risk of infection with opportunistic viral, fungal, bacterial, and protozoal pathogens. In addition, steatosis and lipodystrophy now are recognized more commonly in patients who have HIV, particularly in the setting of ART. Thus, understanding of liver diseases in the setting of HIV infection becomes an important focus in caring these individuals. There have been numerous advances in the treatment of liver disease in patients who have HIV, particularly in treating viral hepatitis C and B. This article reviews various liver manifestations in patients who have HIV and the recent advances in diagnostic and therapeutic options.

Management and treatment of hepatitis C virus infection in HIV-infected adults: recommendations from the Veterans Affairs Hepatitis C Resource Center Program and National Hepatitis C Program Office

Nearly 40% of human immunodeficiency virus- (HIV-) infected veterans on highly active antiretroviral therapy (HAART) in the United States are coinfected with hepatitis C virus (HCV). With the increased survival due to declining opportunistic infections as a result of HAART, HCV-associated liver disease has become a leading cause of death in HIV-infected individuals. HCV infection has been shown to lead to rapid progression of HCV-related liver disease in HIV infection. Results from recent clinical trials in HIV/HCV-coinfected patients show improved response rates using pegylated formulations of interferon plus ribavirin when compared to standard interferon plus ribavirin. However, the treatment of HCV in HIV/HCV-coinfected patients can be complicated by the hepatotoxic and myelosuppressive effects of HIV therapy and HIV infection itself. Prior to initiating HCV therapy, HIV therapy should be optimized by improving immune suppression and avoiding specific antiretroviral drugs that may cause hepatotoxicity and myelosuppression. In the event of treatment-related neutropenia or anemia during HCV therapy, the use of growth factors should be considered to maximize sustained virologic response to HCV therapy. In HIV/HCV-coinfected patients with end-stage liver disease, liver transplantation is being investigated and shows promise as a potential therapeutic option. With the recent advances in the treatment of HCV in HIV/HCV-coinfected individuals, all HIV/HCV-coinfected patients eligible for HCV treatment should be evaluated for HCV combination therapy with careful consideration of their HIV disease.

Prevalence of hepatitis C in an ethnically diverse HIV-1-infected cohort in south London

OBJECTIVES

There is limited information on the prevalence of and risk factors for hepatitis C virus (HCV) infection among HIV-1-infected patients in the UK. Our objective was to determine the prevalence of HCV infection among an ethnically diverse cohort of HIV-infected patients in south London, and to extrapolate from these data the number of co-infected patients in the UK.

METHODS

A total of 1017 HIV-1-infected patients who had attended King's College Hospital HIV clinic between September 2000 and August 2002 were screened for HCV antibody using a commercial enzyme-linked immunosorbent assay (ELISA). Positive results were confirmed by polymerase chain reaction (PCR) or recombinant immunoblot assay. Demographic, clinical and laboratory data were obtained from the local computerized database and medical records. We applied our HCV prevalence rates in the different HIV transmission groups to the estimated number of HIV-infected persons in these groups in the UK, to obtain a national estimate of the level of HIV-HCV co-infection.

RESULTS

Of the 1017 HIV-1-infected patients, 407 (40%) were white men, 158 (15.5%) were black African men, 268 (26.3%) were black African women, and 61 (6%) and 26 (2.6%) were black Caribbean men and women, respectively. Heterosexual exposure was the most common route of HIV acquisition (53.5%), followed by men having sex with men (36.9%), and current or previous injecting drug use (IDU) (7.2%). The overall prevalence of HCV co-infection was 90/1017 (8.9%), but this varied substantially according to route of transmission, from 82.2% among those with a history of IDU (which accounted for 67% of all HCV infections), to 31.8% in those who had received blood products, to 3.5% and 1.8% in those with homosexually and heterosexually acquired infection, respectively. Multivariate logistic regression analysis identified several independent risk factors for HCV infection: a history of IDU [odds ratio (OR) = 107.2; 95% confidence interval (CI) = 38.5-298.4], having received blood products (OR = 16.5; 95% CI = 5.1-53.7), and either being from a white ethnic group (OR = 4.3; 95% CI = 1.5-12.0) or being born in Southern Europe (OR = 6.7; 95% CI = 1.5-30.7). Based on the 35,473 known HIV-1-infected persons in the UK and the 10 997 estimated to be unaware of their status, we projected that there are at least 4136 HIV-HCV co-infected individuals in the UK and 979 who are unaware of their status.

CONCLUSIONS

Overall, 9% of our cohort was HIV-HCV co-infected. The prevalence was highest among intravenous drug users (82%), who accounted for most of our HCV cases, and lowest among heterosexual men and women from sub-Saharan Africa and the Caribbean [< 2%]. Our estimate that a significant number of co-infected persons may be unaware of their HIV and HCV status, highlights an urgent need to increase the uptake of HCV and HIV testing, particularly among injecting drug users, to reduce the risk of onward transmission.

Therapeutic Interventions for HIV Infection and Chronic Viral Hepatitis

Combination antiretroviral therapy reduces overall and liver-specific morbidity and mortality in coinfection with human immunodeficiency virus (HIV) and hepatitis C virus (HCV) and represents the most beneficial pharmaceutical treatment intervention for most coinfected patients. Antiviral therapy for HCV infection is potentially organ- and life-saving but, in general, should be reserved for patients who achieve suppression of HIV RNA and immune restoration from combination antiretroviral therapy or for patients with nadir CD4+ T lymphocyte levels of >350 cells/microL. Safe and virologically active treatment of coinfection with HIV and hepatitis B virus can be concurrently achieved by the use of combination antiretroviral therapy regimens containing lamivudine and/or tenofovir.

Update on Hepatitis B and C Coinfection in HIV

Coinfection with hepatitis B virus (HBV) or hepatitis C virus (HCV) is common in patients with HIV infection. HIV infection and immunosuppression alter the natural history of chronic viral hepatitis, and some patients experience accelerated progression to clinically significant liver disease. Therapies used in the treatment of HBV or HCV monoinfection have been applied to the treatment of HIV-coinfected patients. However, development of viral resistance and lack of virologic response remain significant areas of concern. Timely diagnosis and clinical staging of chronic hepatitis infection are critical in the management of HIV-coinfected patients.

Unsafe sex and increased incidence of hepatitis C virus infection among HIV-infected men who have sex with men: the Swiss HIV Cohort Study

BACKGROUND

Data on the incidence of hepatitis C virus (HCV) infection among human immunodeficiency virus (HIV)-infected persons are sparse. It is controversial whether and how frequently HCV is transmitted by unprotected sexual intercourse.

METHODS

We assessed the HCV seroprevalence and incidence of HCV infection in the Swiss HIV Cohort Study between 1988 and 2004. We investigated the association of HCV seroconversion with mode of HIV acquisition, sex, injection drug use (IDU), and constancy of condom use. Data on condom use or unsafe sexual behavior were prospectively collected between 2000 and 2004.

RESULTS

The overall seroprevalence of HCV infection was 33% among a total of 7899 eligible participants and 90% among persons reporting IDU. We observed 104 HCV seroconversions among 3327 participants during a total follow-up time of 16,305 person-years, corresponding to an incidence of 0.64 cases per 100 person-years. The incidence among participants with a history of IDU was 7.4 cases per 100 person-years, compared with 0.23 cases per 100 person-years in patients without such a history (P<.001). In men who had sex with men (MSM) without a history of IDU who reported unsafe sex, the incidence was 0.7 cases per 100 person-years, compared with 0.2 cases per 100 person-years in those not reporting unsafe sex (P=.02), corresponding to an incidence rate ratio of 3.5 (95% confidence interval, 1.2-10.0). The hazard of acquiring HCV infection was elevated among younger participants who were MSM.

CONCLUSIONS

HCV infection incidence in the Swiss HIV Cohort Study was mainly associated with IDU. In HIV-infected MSM, HCV infection was associated with unsafe sex.

Hepatotoxicity and nelfinavir: a meta-analysis

BACKGROUND & AIMS

The inclusion of protease inhibitors in 3-drug highly active antiretroviral regimens for treating patients who are infected with human immunodeficiency virus-1 has had a significant impact in increasing survival and decreasing morbidity. However, the effectiveness of this class of drugs may be compromised by the occurrence of drug-related hepatotoxicity, which is problematic especially in individuals co-infected with hepatitis viruses. Based on its clinical and pharmacologic profile, especially its unique pattern of resistance, nelfinavir has been used frequently as a first-line protease-inhibitor therapy for human immunodeficiency virus-1-infected patients. The aim of this study was to identify the relative potential for developing hepatotoxicity for nelfinavir vs other protease inhibitors.

METHODS

An exploratory meta-analysis of liver enzyme level increases was conducted in a combined total of 4268 patients derived from 3 large recently conducted prospective and retrospective clinical trials and a prospective cohort study.

RESULTS

The results indicate that among 4 commercially available protease inhibitors and a 2-protease inhibitor combination, nelfinavir and indinavir are associated with the lowest rates of occurrence of severe hepatotoxicity (ie, combined estimates of liver enzyme level increases of 2.9% and 3.1%, respectively). The low rate of occurrence of severe hepatotoxicity for nelfinavir was shown even among patients co-infected with hepatitis viruses.

CONCLUSIONS

In conclusion, these data provide support for the conclusion that differences in the potential for hepatotoxicity do exist among the commercially available protease inhibitors.

Therapies for HIV and viral hepatitis coinfection

The natural history of chronic viral hepatitis is altered by HIV coinfection. Liver fibrosis rates and clinical features of liver disease develop more rapidly. Although HIV-hepatitis C virus coinfected subjects may progress more rapidly to AIDS, this is probably explained by comorbid illness, substance abuse and socioeconomic circumstances. Safe and virologically active treatment of HIV-hepatitis B virus coinfection can be concurrently achieved by the use of highly active antiretroviral therapy regimens containing lamivudine and/or tenofovir. In most cases, highly active antiretroviral therapy represents the most beneficial initial pharmaceutical intervention for HIV-hepatitisC virus coinfection. HepatitisC virus antiviral therapy should, in most cases, be reserved for those achieving HIV RNA suppression and immune restoration from highly active antiretroviral therapy or with nadir CD4 T-lymphocytes above 350 cells/microl.

Management of Hepatitis C in HIV-infected Patients

As the survival of HIV-infected patients has been lengthening over the past 10 years as a consequence of effective antiretroviral therapy, hepatitis C virus (HCV) coinfection has emerged as a major cause of morbidity and mortality in this population. HCV/HIV coinfection is associated with accelerated progression of liver disease, untoward effects on the immunologic and virologic response to antiretroviral medications, and possibly with a more aggressive course of HIV disease. The results of major trials of combination therapy for HCV in coinfected patients have clearly established the combination of pegylated interferon-alpha with ribavirin as the treatment of choice in this population. However, the effectiveness and tolerability of this regimen remains suboptimal, particularly in patients with genotype 1 HCV infection. This paper reviews the impact of HCV coinfection in HIV-infected patients, outlines current concepts on management and antiviral treatment, and discusses some of the newer agents, currently in the therapeutic pipeline, that are directed against novel molecular targets.

Hepatitis C coinfection increases the risk of fulminant hepatic failure in patients with HIV in the HAART era

BACKGROUND/AIMS

It is uncertain if patients coinfected with hepatitis C and HIV are more likely to suffer fulminant hepatic failure (FHF) when compared to patients with HIV-only.

METHODS

We conducted a retrospective cohort study using national administrative databases from the Department of Veterans Affairs in patients hospitalized for the first time with HIV and/or hepatitis C between 10/1991 and 9/2000. Fulminant hepatic failure was defined as occurring after the index hospitalization through 9/2001 in the absence of pre-existing liver disease. We calculated incidence rates, Kaplan Meier cumulative incidence curves, and Cox proportional hazards ratios while adjusting for demographics and other potential confounders.

RESULTS

We identified 11,678 patients with HIV-only and 4761 patients with coinfection. There were 92 cases of fulminant hepatic failure yielding an incidence rate of 1.1/1000 person-years and 2.5/1000 person-years in the HIV-only and coinfected groups. The cumulative incidence of fulminant hepatic failure in the coinfected group was higher than in the HIV-only group (P<0.0001). The risk of fulminant hepatic failure in patients with coinfection compared to HIV-only during the HAART era was several folds higher than that during the pre-HAART era.

CONCLUSIONS

HAART and hepatitis C coinfection appeared to act synergistically in HIV-infected patients to increase the risk of fulminant hepatic failure, a rare but often fatal disease.

A Study to Investigate the Impact of the Initiation of Highly Active Antiretroviral Therapy on the Hepatitis C Virus Viral Load in HIV/HCV-Coinfected Patients

Changes in the hepatitis C virus (HCV) viral load (VL) were assessed in a retrospective study of 50 HIV/HCV-coinfected patients who initiated highly active antiretroviral therapy (HAART). Most patients responded to HAART [during the first 6 months, plasma HIV VL fell by a mean 1.39 log10, becoming undetectable (<400 copies/ml) in 22% and CD4+ T cells increased by a mean of 100 cells/μl], but surprisingly, 27 (54%) showed some rise and 25 (50%) showed a significant increase in the HCV VL. This figure was considered to be a minimum estimate. A majority of the patients showed an increase of less than 1 log10 that was associated with a rapid decrease in the HIV VL, whereas an increase in the HCV VL of greater than 1 log10, noted in eight patients, was associated with a baseline CD4+ cell count of less than 200 cells/μl. The increase in the HCV VL was not associated with hepatitis as determined by raised alanine transferase.

Longitudinal study in HIV/HCV-coinfected HAART-naive patients and role of HCV genotype

To evaluate the impact of highly active antiretroviral therapy (HAART) on the course of hepatitis C (HCV) infection, we studied the biological and virological characteristics of 23 HCV/HIV-coinfected HAART-naive patients. The HCV genotype, HCV and HIV viral loads, serum alanine aminotransferase, CD4+ and CD8+ cell/mm3 were determined at baseline, 1 month, 6 months and 12 months after initiation of HAART. Results were analyzed both in terms of total population and of HCV genotype. The study of the total population suggests that this therapy did not determine a significant alteration of HCV viremia and levels of ALT, while a significant decrease in HIV viremia (-1.7log10 at one year from the start of HAART) and increase in CD4+ counts was observed (P < 0.005). The biological and virological parameters of HCV/HIV coinfection differed according to the HCV genotype. In particular, only genotype 4 showed a significant inverse correlation between HCV and HIV viral loads.

Influence of liver fibrosis on highly active antiretroviral therapy-associated hepatotoxicity in patients with HIV and hepatitis C virus coinfection

BACKGROUND

Coinfection with hepatitis C virus (HCV) and human immunodeficiency virus (HIV) is a known risk factor for hepatotoxicity in patients receiving highly active antiretroviral therapy (HAART). The aim of this study was to evaluate the role of HCV-related liver fibrosis in HAART-associated hepatotoxicity.

METHODS

In a prospective study involving 107 patients who underwent liver biopsy, fibrosis was graded according 5 stages, from F0 (no fibrosis) to F4 (cirrhosis). Hepatotoxicity was defined as an increase in levels of aspartate aminotransferase and alanine aminotransferase to >5 times the upper limit of normal, or a >3.5-fold increase if baseline levels were abnormal. The incidence of hepatotoxicity was compared with liver fibrosis stage and with time and composition of HAART.

RESULTS

Overall, 27 patients (25%) had hepatotoxic events (5.1 events/100 person-years of therapy). The incidence was greater for patients with stage F3 or F4 fibrosis (38%) than for those with stage F1 or F2 fibrosis (15%; 7.6 vs. 3 events/100 person-years; relative risk, 2.75; 95% confidence interval, 1.08-6.97; P=.013). Duration of HCV infection, duration of HAART, diagnosis of acquired immunodeficiency syndrome, HCV load, HCV genotype, and nadir CD4(+) cell count did not affect the risk of hepatotoxicity. Of the 86 patients who received nonnucleoside reverse-transcriptase inhibitors (NNRTIs), 11 (13%) developed liver toxicity. In these patients, fibrosis stages F1 and F2 were associated with similar rates of toxicity (3 events/100 person-years for patients who received nevirapine, 3.3 events/100 person-years for those who received efavirenz, and 3.4 events/100 person-years for those who received non-NNRTIs). There was a greater incidence among patients with F3 or F4 fibrosis who received NNRTIs (11.7 events/100 person-years for patients who received nevirapine, and 8.6 events/100 person-years for those who received efavirenz), compared with those who received non-NNRTIs (4 events/100 person-years).

CONCLUSIONS

HAART-associated hepatotoxicity correlates with liver histological stage in patients coinfected with HIV and HCV. There was no difference in hepatotoxicity risk for different antiretroviral therapies in patients with mild-to-moderate fibrosis.

Avances en el diagnóstico y tratamiento de la infección por el VHC en pacientes con y sin infección por el VIH

The chronic infection by the hepatits C virus represents a serious sanitary problem affecting 1-3% of the world-wide population. It is transmitted by sexual route, vertical route and mainly after blood exposure by percutanea route. While HIV shares similar routes of transmission, the co-infection HCV-HIV is very frequent and the chronic hepatopathy and complications associated with its clinical course are an important cause of morbi-mortality in this population. The gold standard of the treatment for the HCV, has been the interferon and later the combination therapy of interferon plus ribavirine. Currently, the combination of ribavirine and a new pegilated formulation of the interferon has become the standard in the treatment reaching rates of sustained viral response around 40-80%.

Hepatotoxicity of Antiretrovirals

Hepatotoxicity is a relevant adverse effect derived from the use of antiretrovirals that may increase the morbidity and mortality among treated HIV-infected patients and challenges the treatment of HIV infection. Although several antiretrovirals have been reported to cause fatal acute hepatitis, they most often cause an asymptomatic elevation of transaminase levels. In addition to ruling out a variety of processes not related to the use of antiretrovirals or to the HIV infection, for appropriate management of the complication it is necessary to deduce the possible pathogenic mechanisms of the hepatotoxicity. Among these mechanisms, direct drug toxicity, immune reconstitution in the presence of hepatitis C virus (HCV) and/or hepatitis B virus (HBV) co-infections, hypersensitivity reactions with liver involvement and mitochondrial toxicity play a major role, although several other pathogenic pathways may be involved. Liver toxicity is more frequent among subjects with chronic HCV and/or HCB co-infections and alcohol users. Complex immune changes that alter the response against hepatitis virus antigens might be involved in the elevation of transaminase levels after suppression of the HIV replication by highly active antiretroviral therapy (HAART) in patients co-infected with HCV/HBV. The contribution of each particular drug to the development of hepatotoxicity in a HAART regimen is difficult to determine. The incidence of liver toxicity is not well known for most of the antiretrovirals. Although it is most often mild, fatal cases of acute hepatitis linked to the use of HAART have been reported across all families of antiretrovirals. Acute hepatitis is related to hypersensitivity reactions in the case of non-nucleosides and to mitochondrial toxicity in the case of nucleoside analogues. Alcohol intake and use of other drugs are other co-factors that increase the incidence of transaminase level elevation among HIV-infected patients. The management of liver toxicity is based mainly on its clinical impact, severity and pathogenic mechanism. Although low-grade HAART-related hepatotoxicity most often spontaneously resolves, severe grades may require discontinuation of the antiretrovirals, for example when there is liver decompensation, hypersensitivity reaction or lactic acidosis.

Differing patterns of liver disease progression and hepatitis C virus (HCV) quasispecies evolution in children vertically coinfected with HCV and human immunodeficiency virus type 1

Hepatitis C virus (HCV) quasispeciation was studied in two children vertically coinfected with HCV and human immunodeficiency virus type 1 (HIV-1). HCV quasispecies diversification and liver injury were more significant in patient C1, who was immunocompetent with anti-HIV therapy, than in patient C2, who was immunosuppressed, in consistency with modulation of HCV quasispeciation and liver injury by immunocompetence in coinfected children.

Differing patterns of liver disease progression and hepatitis C virus (HCV) quasispecies evolution in children vertically coinfected with HCV and human immunodeficiency virus type 1

Hepatitis C virus (HCV) quasispeciation was studied in two children vertically coinfected with HCV and human immunodeficiency virus type 1 (HIV-1). HCV quasispecies diversification and liver injury were more significant in patient C1, who was immunocompetent with anti-HIV therapy, than in patient C2, who was immunosuppressed, in consistency with modulation of HCV quasispeciation and liver injury by immunocompetence in coinfected children.

Illness of Immune Reconstitution: Recognition and Management

Some individuals who initiate highly active antiretroviral therapy (HAART) develop new or worsening opportunistic infections or malignancies despite improvements in surrogate markers of HIV-1 infection. These events of paradoxical clinical worsening, also known as immune reconstitution syndromes (IRS), are increased in individuals with prior opportunistic infections or low CD4+ T-cell nadirs. They are thought to result from reconstitution of the immune system's ability to recognize pathogens or tumor antigens that were previously present, but clinically asymptomatic. There is no consensus regarding the diagnostic criteria or pathogenesis of IRS. Knowledge of their presentation and treatment is largely based on case reports. With the introduction of HAART into resource-limited settings, it is likely that significantly more and distinct forms of IRS will be observed. Prospective studies of the incidence and treatment of IRS in multiple settings are critical to better understand their pathogenesis and optimal management.

Special considerations in the initiation and management of antiretroviral therapy in individuals coinfected with HIV and hepatitis C

BACKGROUND

Although hepatitis C (HCV) treatment efficacy has improved in recent years, the majority of HIV/HCV-coinfected individuals may not enjoy the full benefits of these treatments and appropriate HIV management is crucial. Evidence is accumulating regarding the impact of HIV/HCV coinfection on the response to, and safety and tolerability of, antiretroviral therapy (ART) in this population.

METHODS

Computerized, English-language literature searches of MEDLINE and PubMed databases (January 1985 to May 2004) for studies of HIV and HCV infection in humans to examine critically (a) the impact of HCV on the HIV virologic and immunologic response to ART; (b) the safety and tolerability of ART in coinfected individuals; and (c) the relationship between immune suppression and immune restoration on hepatic injury.

RESULTS

Three key messages emerged regarding the use of ART in HIV/HCV-coinfected individuals: (a) although HCV appeared to have no impact on HIV virologic response, the data are equivocal regarding immunologic response; (b) morbidities associated with HCV infection, such as insulin resistance, diabetes, mitochondrial dysfunction, and liver inflammation, are also associated toxicities of ART, and (c) both immune suppression and restoration can contribute to the onset and acceleration of HCV-related liver disease.

CONCLUSIONS

The CD4 cell count threshold for initiating ART in HIV/HCV-coinfected patients may be higher because of the impact of immune suppression and restoration on the onset of HCV-associated liver disease and the possibility of a blunted immune response to ART at lower CD4 cell counts. Further, overlapping morbidity between HCV-related mitochondrial and metabolic disease manifestations and ART toxicities warrant careful attention by clinicians.

Tumid lupus erythematosus occurring following highly active antiretroviral therapy for HIV infection: A manifestation of immune restoration

Tumid lupus erythematosus (LE) is a relatively rare and only recently recognized subset of chronic cutaneous lupus. We report a case occurring in a male with HIV infection whereby his rash was only unmasked by immune restoration following highly active antiretroviral therapy (HAART). The phenomenon of latent inflammatory or autoimmune disease appearing following HAART is now recognized as the "immune restoration syndrome" and tumid LE has not been reported in this setting previously. Fortunately this variant of lupus does not result in scarring and is responsive to anti-malarials, allowing continuation of HAART in this patient.

Lymphocyte T helper-specific reactivity in sustained responders to interferon and ribavirin with negativation (seroreversion) of anti-hepatitis C virus

BACKGROUND

Seroreversion, negativation of anti-hepatitis C virus previously positive, is sometimes found in some chronic hepatitis C-sustained responders (SRs) to antiviral therapy.

AIMS

To determine the probability of seroreversion in SR treatment with Interferon and Ribavirin, and lymphocyte T helper (CD4+) reactivity to HCV antigens.

METHODS

Thirty SR were followed on average for 54.8 months. Anti-HCV was tested by third generation test. Peripheral blood mononuclear cells (PBMCs) were isolated from venous blood and cultured to evaluate CD4+ proliferation in response to 2 microg/ml of eight HCV recombinant antigens from core, NS3, NS4, NS5 regions.

RESULTS

Seroreversion was verified in 23% of patients (7/30), appearing at 47.5+/-24.0 months. The probability of anti-HCV loss in this group was 25% at 56 months after ending therapy. In 57% (4/7), anti-HCV returned to positive. These 7 SR patients with seroreversion also showed weaker CD4+ reactivity in 5% of tests (3/56) than the remaining 23 anti-HCV-positive SRs who showed stronger reactivity in 18% of tests (33/184), P=0.036.

CONCLUSIONS

One-quarter of the SR showed seroreversion of anti-HCV and weaker CD4+ specific HCV proliferation than those who remained anti-HCV positive. The data suggest that complete viral eradication is a possible and achievable clinical objective.

Lopinavir/ritonavir treatment in HIV antiretroviral-experienced patients: evaluation of risk factors for liver enzyme elevation

OBJECTIVES

To evaluate the risk factors for lopinavir/ritonavir (LPV/r)-related liver enzyme elevation (LEE) in HIV antiretroviral-experienced patients.

METHODS

An open prospective observational study was carried out to analyse the incidence and time of LEE development during LPV/r treatment, and to determine whether LEE development was correlated with epidemiological, clinical and biochemical data, immune and virological profiles, concomitant hepatic diseases, antiretroviral therapy, or histological and ultrasonography liver examination results. A diagnosis of LEE was considered when LEE symptoms occurred after LPV/r introduction and was confirmed by a second control within 2 weeks.

RESULTS

A total of 782 HIV-positive outpatients have been enrolled in six different Infectious Diseases Departments in Northern Italy since August 2000. Of these patients, 71 (9.1%) developed LEE within 115+/-85 days (mean+/-standard deviation); 13 of these subjects discontinued LPV/r and four were hospitalized. Of the patients with LEE, 74.6% and 25.4% had grade 2 and > or =3 toxicity, respectively. No correlation between LEE and sex, baseline CD4 cell count, viral load, HIV stage, triglyceride values, histological and ultrasonography liver examination results, nevirapine use, or increase in CD4 cell count was observed. Higher baseline alanine aminotransferase (ALT) and gamma-glutamyltransferase (GGT) values (P < 0.0001 and P=0.004, respectively), younger age (P=0.008), previous hepatitis B virus (HBV) infection (P=0.012), efavirenz use (P=0.04), and hepatitis C virus (HCV) and/or HBV coinfection (P < 0.0001, relative risk 4.78) were significantly related to LEE. No correlations between LEE and the same risk factors as investigated in the whole study population were found in subgroups of patients with HCV and/or HBV infection.

CONCLUSIONS

HCV and HBV testing and measurement of baseline ALT values are essential for screening subjects at risk of LEE before starting LPV/r. Strict monitoring of clinical and biochemical parameters should be performed in these patients.

Immune restoration disease after antiretroviral therapy

Suppression of HIV replication by highly active antiretroviral therapy (HAART) often restores protective pathogen-specific immune responses, but in some patients the restored immune response is immunopathological and causes disease [immune restoration disease (IRD)]. Infections by mycobacteria, cryptococci, herpesviruses, hepatitis B and C virus, and JC virus are the most common pathogens associated with infectious IRD. Sarcoid IRD and autoimmune IRD occur less commonly. Infectious IRD presenting during the first 3 months of therapy appears to reflect an immune response against an active (often quiescent) infection by opportunistic pathogens whereas late IRD may result from an immune response against the antigens of non-viable pathogens. Data on the immunopathogenesis of IRD is limited but it suggests that immunopathogenic mechanisms are determined by the pathogen. For example, mycobacterial IRD is associated with delayed-type hypersensitivity responses to mycobacterial antigens whereas there is evidence of a CD8 T-cell response in herpesvirus IRD. Furthermore, the association of different cytokine gene polymorphisms with mycobacterial or herpesvirus IRD provides evidence of different pathogenic mechanisms as well as indicating a genetic susceptibility to IRD. Differentiation of IRD from an opportunistic infection is important because IRD indicates a successful, albeit undesirable, effect of HAART. It is also important to differentiate IRD from drug toxicity to avoid unnecessary cessation of HAART. The management of IRD often requires the use of anti-microbial and/or anti-inflammatory therapy. Investigation of strategies to prevent IRD is a priority, particularly in developing countries, and requires the development of risk assessment methods and diagnostic criteria.

Dissociation of serum and liver hepatitis C virus RNA levels in patients coinfected with human immunodeficiency virus and treated with antiretroviral drugs

We examined hepatitis C virus (HCV) RNA levels in serum, peripheral blood mononuclear cells (PBMC), and the liver for 135 patients with chronic HCV infections, 44 of whom were human immunodeficiency virus (HIV) positive and treated with highly active antiretroviral therapy (group A), 66 of whom were HIV negative (group B), with abnormal serum alanine aminotransferase (ALT) values, and 25 of whom were HIV negative, with ALT values of </=1.5 times the normal value (group C). Patients had not been treated with interferon, with or without ribavirin, at the time of the study. A statistically significant correlation between HCV RNA levels in the liver and serum was reproducibly documented, whereas this was inconsistent for serum and PBMC. A comparative evaluation of HCV RNA levels in the liver and PBMC showed significantly lower values for group A than for groups B and C (P < 0.01 and P < 0.0001, respectively). In contrast, HCV RNA levels in serum were significantly higher for group A than for group B (P < 0.001). A dissociation between HCV RNA levels in serum and the liver was found for patients with HIV-HCV coinfections. Although the relative contribution of extrahepatic reservoirs, including lymphoid cells, to HCV RNA levels in serum is unclear, it may be speculated that a low intrahepatic HCV burden is caused by restored immunocompetence after successful antiretroviral therapy in coinfected patients.

Hepatitis C and HIV co-infection

HIV accelerates progression of hepatitis C virus (HCV)-related liver disease. There are conflicting data on the effect of HCV on the risk of HIV progression and CD4 response to highly active antiretroviral therapy (HAART). Long-term prospective cohort studies are clearly required to resolve these issues. The optimal management of the co-infected patient is also unclear. For the co-infected patient, the optimal HAART regimen for best immune CD4 recovery and least adverse reactions remains unclear. Unfortunately, current HCV treatment is associated with significant side effects and a considerable proportion of HIV co-infected patients are poor candidates for HCV treatment. Better and more effective treatment for HCV (preferably not based on interferon) is urgently required for this group of patients. Patients with good CD4 cell count and with HCV genotypes 2 and 3 are likely to have a reasonable response to treatment.

Longitudinal effect of antiretroviral therapy on markers of hepatic toxicity: impact of hepatitis C coinfection

To characterize longitudinal hepatic toxicity of antiretroviral therapy in HIV-infected women with and without hepatitis C virus (HCV) infection, we measured alanine and aspartate aminotransferase values among women initiating highly active antiretroviral therapy (HAART). For 312 HIV/HCV coinfected women who received HAART for a mean of 1.8 years, the prevalence of elevated aminotransferase levels >3 times and >5 times the upper limit of normal (ULN) was low (<12% and <4%, respectively), and the prevalence of elevated aminotransferase levels declined over time. When we analyzed trends in aminotransferase levels according to type of HAART received among HCV-infected and uninfected women, we found that mean aminotransferase levels declined among 539 women receiving therapy with protease inhibitors (decreases of 5.34%-4.23% of the ULN per year; P values for trend of.007-.06), but mean values among 128 women receiving therapy with nonnucleoside reverse-transcriptase inhibitors remained stable (from decreases of 1.65% to increases of 7.57% of the ULN per year; P values of.19-.71). Our findings lend support to assertions that antiretroviral therapy is safe for women with HCV infection.

Cerebral CD8+ lymphocytosis in HIV-1 infected patients with immune restoration induced by HAART

In HIV infected persons, highly active antiretroviral therapy (HAART) has reduced both the morbidity and incidence of several disorders. Its effects on direct HIV-induced damage to the CNS remain controversial. In addition, HAART may provoke an "immune reconstitution inflammatory syndrome" (IRIS). Herein we report two patients who, despite HAART, developed a diffuse encephalopathy. Their clinical, radiological and neuropathological features are described. Immunohistochemical and PCR analyses were used to detect HIV and to exclude other viruses in brain tissue. The unusual inflammatory reaction in the brain tissue was defined by immunohistochemistry. Both patients had advanced HIV disease with low CD4 counts and high HIV "viral loads" before starting HAART. In both, HAART induced an increase in CD4 count and a marked reduction in HIV viral load, which was accompanied, in patient one, by worsening of pre-existing, and, in patient two, by development of, acute encephalopathy. At post-mortem examination, the brain of patient one showed HIV encephalitis. In addition, the brains of both patients revealed HIV-DNA by PCR, diffuse microglial hyperplasia and massive and diffuse perivascular and intraparenchymal infiltration by CD8+/CD4- lymphocytes. We suggest that the rapid immune reconstitution induced by HAART in these two patients led to a redistribution of lymphocytes into peripheral blood. This was followed by recruitment of CD8+ lymphocytes into the brain, which resulted in the diffuse infiltration described. The appearances in patient two further suggest that HIV brain infection, even without encephalitis, is sufficient to trigger this response.

Immune reconstitution in HIV-infected patients

The prognosis of patients infected with human immunodeficiency virus (HIV) type 1 has dramatically improved since the advent of potent antiretroviral therapies (ARTs), which have enabled sustained suppression of HIV replication and recovery of CD4 T cell counts. Knowledge of the function of CD4 T cells in immune reconstitution was derived from large clinical studies demonstrating that primary and secondary prophylaxis against infectious agents, such as Pneumocystis jirovecii (Pneumocystis carinii), Mycobacterium avium complex, cytomegalovirus, and other pathogens, can be discontinued safely once CD4 T cell counts have increased beyond pathogen-specific threshold levels (usually >200 CD4 T cells/mm3) for 3-6 months. The downside of immune reconstitution is an inflammatory syndrome occurring days to months after the start of ART, with outcomes ranging from minimal morbidity to fatal progression. This syndrome can be elicited by infectious and noninfectious antigens. Microbiologically, the possible pathogenic pathways involve recognition of antigens associated with ongoing infection or recognition of persisting antigens associated with past (nonreplicating) infection. Specific antimicrobial therapy, nonsteroidal anti-inflammatory drugs, and/or steroids for managing immune reconstitution syndrome should be considered.

HIV infection and hepatic enzyme abnormalities: intricacies of the pathogenic mechanisms

Liver enzyme elevations are common in human immunodeficiency virus (HIV)-infected patients, and their diagnosis or management may be difficult because of the intricacies of the pathogenic mechanisms involved. These include hepatotoxicity related to the highly active antiretroviral therapy (HAART) regimen, idiosyncratic or immunoallergic mechanisms, and direct cytotoxicity enhanced by an underlying liver disease. Liver enzyme abnormalities may also reflect hepatitis B (HBV) or hepatitis C (HCV) infection, which each have their own risks for chronic immune-mediated liver disease (including hepatitis flare after immune reconstitution) and of direct cytotoxicity. Finally, other factors may affect liver deterioration, including alcohol-related liver disease, nonalcoholic steatohepatitis associated with metabolic syndromes (e.g., hyperlipidemia, diabetes, or being overweight) that are potentially HAART related, and use of medication or illicit drugs (e.g., methamphetamine). A better understanding of these complex interactions, including adjustments of dosages of antiretroviral drugs, will probably help in the management of HIV-infected patients with liver enzyme abnormalities.

Drug-Induced Liver Injury Associated with Antiretroviral Therapy that Includes HIV-1 Protease Inhibitors

Since their introduction, hepatotoxicity has been associated with the use of human immunodeficiency virus (HIV)-1 protease inhibitors (PIs). However, the complexity of the HIV-infected patient and the combinations of medications used to treat HIV complicate the understanding of the independent effects of PIs in the development of drug-induced liver injury (DILI). I discuss the current understanding of PI-associated hepatotoxicity. Of the PI regimens studied, the greatest risk of DILI has been observed among patients receiving full-dose ritonavir. Similarly, hepatitis B and/or C virus coinfection has been associated with a greater risk of DILI, compared with those with no hepatitis. Although the specific mechanism by which viral hepatitis increases this risk is not known, patients with cirrhosis may have decreased cytochrome P450 activity, leading to increased PI exposure. Clearly, further research is needed to define the interaction of PIs and chronic viral hepatitis in the development of DILI.