Hepatotoxicity associated with antiretroviral therapy containing dual versus single protease inhibitors in individuals coinfected with hepatitis C virus and human immunodeficiency virus

Substance Use, Highly Active Antiretroviral Therapy, and Liver Enzymes: Evidence From a Cross-Sectional Study of HIV-Infected Adult Patients Without Comorbidities on HAART in the University of Port Harcourt Teaching Hospital

This study applied a structural equation modeling (SEM) to evaluate the role of substance use (alcohol, smoking, and trado-medicine use) to changes in the liver enzymes (AST, ALT, and ALP) levels in HIV-infected adult patients on a highly active antiretroviral treatment (HAART) for not <1 year. The study was a cross-sectional, part of a randomized comparative trial (Ref: UPH/CEREMAD/REC/19), involving 129 (46 males and 83 females) HIV-infected adult patients. Liver enzyme levels were determined from analyzed blood samples using the Clinical Chemistry Analyser (VS10) manufactured by Vitro Scient, while the study determined substance use using a reliable (Cronbach alpha = 0.805) rapid-exploratory survey questionnaire. Liver enzyme values were further categorized into: normal or abnormal using normal reference ranges (ALT = 7–55 U/L, AST = 8–48 U/L, and ALP = 40–129 U/L). STATGRAPHICS V16.1.11 (StatPoint Tech., Inc.) and SPSS (IBM® Amos V21.0.0, USA) were used to analyze the data. Among the HIV-HAART patients, 27.9% were alcohol users, 20.9% smokers, and 20.1% trado-medicine users. In addition, ALP (71.3%) abnormality was higher than ALT (34.9%) and AST (28.7%). The result from the SEM provided only a partial support for our hypotheses of direct substance use effects on the liver enzyme levels and abnormalities; with a direct association of alcohol with an elevated AST (b = 0.170, p = 0.05) and smoking with a higher AST (b = 0.484, p < 0.01) and ALT (b = 0.423, p < 0.01) values. Trado-medicine use was not directly associated with enzyme elevation and abnormality. In conclusion, ALP abnormality was the most common, and there is a close association between an elevated ALT and AST, with or without an elevated ALP. The study found that HIV-HAART patients who drink or smoke will have at least one or more abnormal transaminases. The possible explanation to the increased risk among HIV-HAART patients could be associated with the metabolic pressures and supra-additive effects on the livers.

Hepatic Enzyme Alterations in HIV Patients on Antiretroviral Therapy: A Case-Control Study in a Hospital Setting in Ghana

BACKGROUND

Diagnosing hepatic injury in HIV infection can be a herculean task for clinicians as several factors may be involved. In this study, we sought to determine the effects of antiretroviral therapy (ART) and disease progression on hepatic enzymes in HIV patients.

METHODS

A case-control study conducted from January to May 2014 at the Akwatia Government Hospital, Eastern region, Ghana, The study included 209 HIV patients on ART (designated HIV-ART) and 132 ART-naive HIV patients (designated HIV-Controls). Data gathered included demography, clinical history and results of blood tests for hepatic enzymes. We employed the Fisher's, Chi-square, unpaired t-test and Pearson's correlation in analysis, using GraphPad Prism and SPSS. A P value < 0.05 was considered significant.

RESULTS

Median CD4 lymphocyte count of HIV-ART participants (604.00 cells/mm3) was higher than that of HIV-Controls (491.50 cells/mm3; P = 0.0005). Mean values of ALP, ALT, AST and GGT did not differ between the two groups compared (P > 0.05). There was a significant positive correlation between hepatic enzymes (ALP, ALT, AST and GGT) for both groups (p < 0.01 each). Duration of ART correlated positively with ALT (p < 0.05). The effect size of disease progression on hepatic enzymes for both groups was small.

CONCLUSION

Antiretroviral therapy amongst this population has minimal effects on hepatic enzymes and does not suggest modifications in therapy. Hepatic injury may occur in HIV, even in the absence of ART and other traditional factors. Monitoring of hepatic enzymes is still important in HIV patients.

Immune restoration in human immunodeficiency virus and hepatitis C virus coinfected patients after highly active antiretroviral therapy

Objective

To evaluate the influence of hepatitis C virus on immunological and virological responses after highly active antiretroviral therapy initiation in human immunodeficiency virus/hepatitis C virus coinfected patients compared to monoinfected human immunodeficiency virus-infected patients.

Methods

The study enrolled 65 human immunodeficiency virus-1-infected subjects who initiated highly active antiretroviral therapy and attended follow-up visits over 48 weeks from 2008 to 2010. They were grouped based on hepatitis C virus-RNA results. Virological and immunological responses were monitored at baseline and at the end of weeks 12, 24, 36, and 48.

Results

There were 35 human immunodeficiency virus monoinfected and 30 human immunodeficiency virus/hepatitis C virus coinfected patients. In the present study human immunodeficiency virus/hepatitis C virus coinfection did not seem to influence CD4 T-lymphocytes recovery. There was no difference between the curves of CD4 T-lymphocytes raise of coinfected and monoinfected groups.

Conclusion

This prospective study confirms that hepatitis C virus infection does not seem to be associated with impaired CD4 T-lymphocytes recovery after HAART.

Abnormal liver stiffness assessed using transient elastography (Fibroscan®) in HIV-infected patients without HBV/HCV coinfection receiving combined antiretroviral treatment

Background and Aims

Liver stiffness measurement (LSM) using transient elastography (Fibroscan®) can identify individuals with potential underlying liver disease. We evaluated the prevalence of abnormal LSM values as assessed using LSM and its predictors in HIV-infected asymptomatic patients receiving combined antiretroviral treatment (cART) without HBV/HCV coinfection.

Methods

We prospectively recruited 93 patients who had consistently been undergoing cART for more than 12 months at Severance Hospital in Seoul, Republic of Korea, from June to December 2010. LSM values >5.3 kPa were defined as abnormal.

Results

Thirty-nine (41.9%) had abnormal LSM values. On multivariate correlation analysis, the cumulative duration of boosted and unboosted protease inhibitors (PIs) were the independent factors which showed a negative and positive correlation to LSM values, respectively (β = –0.234, P = 0.023 and β = 0.430, P<0.001). In multivariate logistic regression analysis, the cumulative exposure duration of boosted-PIs and γ-glutamyltranspeptidase levels were selected as the independent predictors which showed a negative and positive correlation with abnormal LSM values, respectively (odds ratio [OR], 0.941; 95% confidence interval [CI], 0.889–0.997; P = 0.039 and OR, 1.032; 95% CI, 1.004–1.060; P = 0.023).

Conclusion

The high percentage of HIV-infected asymptomatic patients receiving cART without HBV/HCV coinfection had abnormal LSM values. The cumulative exposure duration of boosted-PIs and γ-GT level were independent predictors which showed a negative and positive correlation with abnormal LSM values, respectively.

Increasing burden of liver disease in patients with HIV infection

Introduction of effective combined antiretroviral therapy has made HIV infection a chronic illness. Substantial reductions in the number of AIDS-related deaths have been accompanied by an increase in liver-related morbidity and mortality due to co-infection with chronic hepatitis B and C viruses. Increases in non-alcoholic fatty liver disease and drug-induced hepatotoxicity, together with development of hepatocellular carcinoma, also potentiate the burden of liver disease in individuals with HIV infection. We provide an overview of the key causes, disease mechanisms of pathogenesis, and recommendations for treatment options including the evolving role of liver transplantation.

Noninvasive procedures to evaluate liver involvement in HIV-1 vertically infected children

OBJECTIVES

: Progressive liver injury is a concern in HIV-infected children exposed to long-term antiretroviral drugs and to the cytopathic effect of HIV. Yet liver biopsy is usually considered too invasive to be repeated in these patients. The aims of this study are to evaluate the feasibility of noninvasive hepatic investigations in HIV-1-infected children, assess the prevalence of signs of liver affection, and analyse the influence of the HIV disease severity and the exposure to antiretroviral therapy.

MATERIALS AND METHODS

: A cross-sectional study conducted in 26 HIV-1 vertically infected children ages 8 to 18 years old. Liver function was assessed with standard serum biochemical markers, FibroTest, ActiTest, SteatoTest, Forns index, aspartate aminotransferase to platelet ratio index, ultrasound, and Fibroscan.

RESULTS

: Nineteen (>60%) children had signs of liver affection on at least 1 of the test results: 13 (50%) had elevated liver enzymes, 15 (63%), 8 (33%), 5 (21%), and 5 (21%) had abnormal FibroTest, ActiTest, Forns index, and aspartate aminotransferase to platelet ratio index results, respectively. Four children (17%) had mild liver steatosis on ultrasound. Fibroscan measures were significantly higher in patients than in age-matched healthy children. Patients with elevated Fibroscan measures also had significantly higher FibroTest results. Age, HIV stage N in the Centers for Disease Control and Prevention classification and exposure duration to nucleoside reverse transcriptase inhibitor and non-nucleoside reverse transcriptase inhibitor drugs were the main risk factors for hepatotoxicity.

CONCLUSIONS

: More than half of our population of HIV-infected children had biological and/or radiological signs of liver affection. Regular follow-up of liver function is necessary in these patients, which is now possible with noninvasive procedures.

Drug-induced hepatotoxicity or drug-induced liver injury

Drug-induced hepatotoxicity is underreported and underestimated in the United States. It is an important cause of acute liver failure. Common classes of drugs causing drug-induced hepatotoxicity include antibiotics, lipid lowering agents, oral hypoglycemics, psychotropics, antiretrovirals, acetaminophen, and complementary and alternative medications. Hepatotoxic drugs often have a signature or pattern of liver injury including patterns of liver test abnormalities, latency of symptom onset, presence or absence of immune hypersensitivity, and the course of the reaction after drug withdrawal.

Management complexities of HIV/hepatitis C virus coinfection in the twenty-first century

Because of shared routes of transmission, hepatitis C virus (HCV) coinfection is common among HIV-infected persons. Because of the effectiveness of antiretroviral therapy, chronic HCV has now emerged as a major cause of morbidity and mortality in this population. Because chronic HCV is highly prevalent among HIV-infected patients and has a rapid disease progression, antiviral therapy with pegylated interferon plus ribavirin is critical for the long-term survival of HIV/HCV-coinfected patients. In this article, the authors review the (1) epidemiology of HCV among HIV-infected individuals, (2) effect of HIV on the natural history of chronic HCV, (3) impact of antiretroviral therapy on HCV coinfection, and (4) management of chronic HCV in the HIV-infected person.

Management of hepatic complications in HIV-infected persons

In the era of effective antiretroviral therapy (ART), liver disease is the second most common cause of death among persons with human immunodeficiency virus (HIV) infection. Liver disease-related deaths mostly result from chronic infection with hepatitis B virus (HBV) and/or hepatitis C virus (HCV). In addition, recent reports suggest that HCV infection may be transmitted sexually between HIV-infected men who have sex with men. Management of these conditions in HIV-infected persons requires careful consideration, balancing the potential benefits of therapy with the potential for significant treatment-related adverse effects (HCV infection) and viral resistance and/or hepatitis flares (HBV infection). Furthermore, several antiretroviral agents are active against HBV infection, including lamivudine, emtricitabine, tenofovir, and, more recently, entecavir. Despite the complexity and potential for antiretroviral-associated hepatotoxicity, ART usually is safe for patients with viral hepatitis coinfection, and, in some cases, treatment for HIV infection may be beneficial for the liver.

An overview of HIV and chronic viral hepatitis co-infection

Combination antiretroviral therapy often controls HIV disease, may indirectly slow HCV progression, and creates an immune environment which may optimize HCV drug therapy response. Monitoring for antiretroviral-related liver adverse events is vital. However, this complication infrequently causes clinically significant liver toxicity. HCV antiviral therapy should, in most cases, be reserved for those abstaining from alcohol and achieving HIV RNA suppression and immune restoration on combination antiretroviral therapy or for those with nadir CD4 counts above 350 cells/mul. Given the high prevalence of HBV and HCV co-infection, chronic viral hepatitis will influence the health and treatment of HIV-infected individuals for the foreseeable future.

Idiosyncratic drug-induced liver injury: an overview

Drug-induced liver injury (DILI) encompasses a spectrum of clinical disease ranging from mild biochemical abnormalities to acute liver failure. The majority of adverse liver reactions are idiosyncratic, occurring in most instances 5-90 days after the causative medication was last taken. The diagnosis of DILI is clinical, based on history, probability of the suspect medication as a cause of liver injury and exclusion of other hepatic disease. DILI can be hepatocellular (predominant rise in alanine transaminase), cholestatic (predominant rise in alkaline phosphatase) or mixed liver injury. An elevated bilirubin level more than twice the upper limit of normal in patients with hepatocellular liver injury implies severe DILI, with a mortality of approximately 10% and with an incidence rate of 0.7-1.3 per 100,000. Although acute liver failure is rare, 13-17% of all acute liver failure cases are attributed to idiosyncratic drug reactions. Response to drug withdrawal may be delayed up to 1 year with cholestatic liver injury with occasional subsequent progressive cholestasis known as the vanishing bile duct syndrome. Overall, chronic disease may occur in up to 6% even if the offending drug is withdrawn. Antibiotics and NSAIDs are the most common cause of DILI. Statins rarely cause significant liver injury whereas antiretroviral therapy is associated with hepatotoxicity in 10% of treated patients. Multiple mechanisms of DILI have been implicated, including TNF-alpha-activated apoptosis, inhibition of mitochondrial function and neoantigen formation. Risk factors for DILI include age, sex and genetic polymorphisms of drug-metabolising enzymes such as cytochrome P450. In patients with human immunodeficiency virus, the presence of chronic viral hepatitis increases the risk of antiretroviral therapy hepatotoxicity. Over the next decade, the combination of accurate case ascertainment of DILI via clinical networks and the application of genomics and proteomics will hopefully lead to accurate prediction of risk of DILI, so that pharmacotherapy can be optimised with avoidance of adverse hepatic events.

Drug-induced liver injury associated with HIV medications

Antiretroviral therapy (ART) for HIV infection frequently has been associated with elevated liver enzyme levels. Determining the cause of elevated liver enzyme levels in patients who have HIV is difficult because ART usually consists of three different drugs, patients may be taking additional hepatotoxic medications and patients who have HIV often suffer from other liver diseases. Several agents, however, are recognized as having noteworthy and specific patterns of toxicity. This article reviews the different HIV drug classes, incidence of elevated liver enzyme values by class and by individual drug, risk factors, specific toxicities, and possible mechanisms of injury.

Risk factors for grade 3-4 liver enzyme elevation in HIV and hepatitis C coinfected patients on combination antiretroviral therapy

Although coinfection with hepatitis C (HCV) is an established risk factor for hepatotoxicity in HIV-positive patients receiving combination antiretroviral therapy (cART), specific variables that may be predictive of severe hepatotoxicity among co-infected patients receiving cART remain poorly defined. A retrospective cohort study of HIV/HCV coinfected adults from two HIV treatment centers covering the period between December 1998 and December 2003 was conducted to address this question. The primary endpoint of the study was the occurrence of grade 3 or 4 elevation of serum alanine aminotransferase (ALT) during follow-up and the primary predictors of interest were specific antiretrovirals. One hundred five coinfected patients receiving cART for a median of 70 months (interquartile range [IQR], 37, 83) were included in the analysis. Twenty-three (22%) patients developed a grade 3 or 4 increase in serum ALT at least once in follow-up. In univariate analysis, current receipt of lopinavir/ritonavir (LPV/r) (odds ratio [OR] 3.09, 95% confidence interval [CI] 1.14-8.34, p = 0.03), baseline ALT (OR 1.01, 95% CI 1.00-1.02, p = 0.004), and current use of boosting ritonavir (OR 2.84, 95% CI 1.16-7.00, p = 0.02) were significantly associated with a grade 3 or 4 increase in serum ALT, although most patients receiving boosting ritonavir were on lopinavir/ritonavir based regimens. Patients receiving LPV/r had been previously exposed to significantly more antiretrovirals (p < 0.0001), protease inhibitors (p < 0.0001), and nucleoside analogues (p = 0.0009) compared to the rest of the cohort. Further research to better clarify risk factors for hepatotoxicity in coinfected patients is warranted given the challenges in treating this population.

AN, Moncau JEC, Marcopito LF, Marques HHDS, Succi RCM, Della Negra M, Hearst N. AIDS by mother-to-child transmission: survival analysis of cases followed from 1983 to 2002 in different regions of Brazil

Antiretroviral therapy contributes to decreasing morbidity and mortality, and ultimately to increasing survival. In Brazil, there are regional differences in HIV epidemiology regarding pregnant women and children with HIV/AIDS. This study evaluates survival time after AIDS diagnosis in 914 children infected by mother-to-child transmission, reported between 1983 and 1998 and followed until 2002, in Brazil's five regions. Time between birth and HIV diagnosis decreased over the years, mainly in the South and Southeast Regions. There was a significant improvement in survival; more than 75% of cases were still living four years after diagnosis in the 1997-1998 group. This Brazilian study demonstrates that even with regional inequalities in health care infrastructure it is possible for a developing country to establish an effective system of universal and free access to antiretroviral therapy that produces a significant increase in survival for children with AIDS.

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.

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.

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.

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.

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.

Role of Liver Biopsy in the Evaluation of Hepatitis C Virus Infection in HIV Coinfection

Hepatitis C virus (HCV) coinfection is common in patients infected with human immunodeficiency virus (HIV), because the viruses share common routes of transmission. With the marked increase in life expectancy of HIV-infected patients associated with the use of highly active antiretroviral therapy, HCV infection has become a significant cause of morbidity and mortality in coinfected patients. As a result, there has been increasing attention to adequate assessment of HCV infection during the last several years. Unlike liver enzymes and HCV RNA levels, which can fluctuate widely and do not correlate with the severity of disease, liver biopsy has become the cornerstone in the evaluation of chronic HCV infection. However, there remain important questions and controversies related to adequately determining the histological severity of liver disease and the role of liver biopsy in HIV-HCV-coinfected patients.

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.

Inhibition of human organic anion transporting polypeptide OATP 1B1 as a mechanism of drug-induced hyperbilirubinemia

OATP1B1 (a.k.a. OATP-C, OATP2, LST-1, or SLC21A6) is a liver-specific organic anion uptake transporter and has been shown to be a higher affinity bilirubin uptake transporter than OATP1B3. Using human embryonic kidney (HEK 293) cells stably transfected with OATP1B1, we have studied the effects of indinavir, saquinavir, cyclosporin A, and rifamycin SV on human OATP1B1 transport function. These drugs are potent inhibitors of OATP1B1 transport activity in vitro. We further provide evidence that the calculated fraction of OATP1B1 inhibited at the clinical exposure level correlated very well with the observed hyperbilirubinemia outcome for these drugs in humans. Our data support the hypothesis that inhibition of OATP1B1 is an important mechanism for drug-induced unconjugated hyperbilirubinemia. Inhibition of OATPs may be an important mechanism in drug-drug and drug-endogenous substance interactions.

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.

Positive virological outcome after lopinavir/ritonavir salvage therapy in protease inhibitor-experienced HIV-1-infected children: a prospective cohort study

BACKGROUND

Lopinavir/ritonavir has demonstrated antiviral activity in the HIV-infected patient.

OBJECTIVE

To analyse virological response to lopinavir/ritonavir therapy in previously protease inhibitor (PI)-experienced HIV-1-infected children.

MATERIALS AND METHODS

Sixty-seven HIV-1-children on lopinavir/ritonavir were studied in a multicentre prospective cohort observational study. The outcome variables were undetectable viral load (uVL; VL < or =400 copies/mL) and virological failure after uVL with a rebound of VL >400 copies/mL. VL and genotype of HIV-1-isolates were measured using standard assays.

RESULTS

83.5% of children had a 1 log10 VL decrease including 65.6% who reached uVL. Children with >2 changes of antiretroviral therapy (ART) or >5 drugs needed a median time of 3-4 months higher than children with < or =2 changes of ART or < or =5 drugs previous to lopinavir/ritonavir, to reach those values, and the relative proportions (RP) were 2.2 (P =0.038) and 1.9 (P=0.050), respectively. Children with CD4+>15% (P=0.122), VL < or =30,000 (P < 0.001) copies/mL, and age >12 years (P=0.096) achieved an earlier control of VL during the follow-up. The children with virological failure or rebound of VL had higher baseline VL and lower CD4+ T-lymphocytes/mm3 and had taken a greater number of drugs previous to lopinavir/ritonavir. HIV-children with a new nucleoside reverse transcriptase inhibitor (NRTI), or protease inhibitor (PI) or PI plus non-nucleoside reverse transcriptase inhibitors (NNRTI) in the current regimen had a better virological response than children without these new drugs. Also, children with <6 protease mutations had an RP of 2.31 of achieving uVL.

CONCLUSIONS

Highly active antiretroviral therapy (HAART) including lopinavir/ritonavir induces beneficial effects in terms of virological outcome responses, and it is an effective option for salvage therapy in PI-experienced HIV-1-infected children.

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.

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.

Cardiovascular disease risk factors and antiretroviral therapy in an HIV-positive UK population

AIM

Although the benefits of antiretroviral therapy (ART) have been dramatic, studies have started to report a variety of drug-related side effects and toxicities. We sought to characterize the risk factors for cardiovascular disease present in an HIV-positive population.

METHODS

A total of 394 HIV-positive ambulant patients attending the Royal Free Hospital, London, were asked to complete a questionnaire. Questions focused on smoking habits and general health.

RESULTS

In total, 38% of patients were aged >40 years, 37% had a family history of heart disease, 3% had diabetes, 14% suffered from raised blood pressure, 20% had a body mass index (BMI)>26 kg/m3, 7% had an alcohol consumption above the recommended UK limit, and 18% had total cholesterol levels >6.3 mmol/L [corrected]. The rate of smoking observed (45%) was much higher than that observed amongst the general population in the British Health Survey for England (34%). There were significant differences between those receiving and not receiving ART. Those on ART tended to be younger (P<0.0001) and less likely to smoke cigarettes (P=0.06) or have an alcohol consumption above the recommended limit (P=0.08), but were more likely to have diabetes (P=0.05). More patients receiving ART reported, and so perceived themselves to have, raised blood fats (P<0.0001). This was confirmed when considering blood lipid levels, where those on ART had significantly raised total cholesterol levels compared to those not currently receiving ART (P<0.0001).

CONCLUSION

We have demonstrated an excess of cardiovascular risk factors in this cohort. These issues must be addressed if we wish to maintain the benefit of treating HIV infection.

Extensive implementation of highly active antiretroviral therapy shows great effect on survival and surrogate markers in vertically HIV-infected children

We performed a retrospective observational study of 253 children vertically infected with human immunodeficiency virus (1994-2001) to assess the effectiveness of antiretroviral therapies (ARTs) on survival and surrogate markers at the population level. Children were divided into 3 groups according to the ART protocols used during the follow-up period: calendar period (CP) 1 (1994-1996) received combined therapy with 2 nucleoside reverse transcriptase inhibitors (NRTIs); CP2 (1997-1998) received implementation of highly active ART (HAART) with 3 drugs (NRTIs, protease inhibitors, and non-NRTIs); and CP3 (1999-2001) received extensive HAART. The children in the CP3 group had statistically significant longer survival periods, lower virus load (VL), highest undetectable VL proportion, and highest CD4+ T cell counts. HAART is effective at the population level at decreasing VL, increasing CD4+ T cells, and increasing the survival in a higher percentage of HIV-infected children.

HIV and hepatitis C coinfection within the CAESAR study

The declining incidence of AIDS-related opportunistic diseases among people with HIV infection has shifted the focus of clinical management to prevention and treatment of comorbidities such as chronic liver disease. The increased risk of hepatitis C virus (HCV)-related advanced liver disease in people with HIV infection makes early HCV diagnosis a priority. To assess HCV prevalence and predictors of HIV/HCV coinfection, we have conducted a retrospective analysis of people enrolled in the CAESAR (Canada, Australia, Europe, South Africa) study, a multinational randomized placebo-controlled study of the addition of lamivudine to background antiretroviral therapy. The impact of HCV on HIV disease progression was also examined. Anti-HCV antibody testing on 1649 CAESAR study participants demonstrated a HIV/HCV coinfection prevalence of 16.1%, which varied from 1.9% in South Africa to 48.6% in Italy. The strongest predictor of HIV/HCV coinfection was HIV exposure category (P<0.0001), with odds ratios (ORs) compared to homosexual as follows: injecting drug use (IDU), 365 [95% confidence interval (CI): 179-742]; transfusion or blood products, 32.2 (95% CI: 15.2-67.6); homosexual and IDU, 22.9 (95% CI: 8.5-62.1). The prevalence of HIV/HCV was low (3.7%) among homosexual men without reported IDU. Other predictors of HIV/HCV coinfection were alanine aminotransferase (ALT), country of residence, ethnicity and stage of HIV disease. A history of IDU or ALT > or =40 U/L at baseline had a positive predictive value (PPV) of 35%, negative predictive value (NPV) of 96%, sensitivity of 82% and specificity of 71% for HIV/HCV coinfection. HIV disease progression was similar in HIV monoinfected and HIV/HCV coinfected patients. People with HIV and a history of IDU or elevated liver function tests should be targeted for HCV testing. The low prevalence of HIV/HCV coinfection among homosexual men without a history of IDU suggests low efficiency of sexual HCV transmission.

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.

Acute liver enzyme elevations in HIV-1-infected patients

BACKGROUND

Acute liver enzyme elevations (ALEE) have been associated with a first-line highly active antiretroviral therapy (HAART) and/or viral hepatitis coinfections in HIV-infected patients. By comparison, the frequency and the risk factors of ALEE in untreated patients and in patients treated with several antiretroviral regimens need to be assessed.

PURPOSE

To describe the long-term frequency and the characteristics of ALEE in antiretroviral treated and untreated patients and to define risk factors for ALEE in a retrospective cohort of HIV-1-infected patients.

METHOD

An HIV-infected cohort was retrospectively examined. ALEE was defined as levels of alanine amino transferase and/or alkaline phosphatase rising to at least 2.5 times above baseline values. Hazard ratios (HR) for ALEE were estimated using an extension of the Cox proportional model taking into account recurrent events.

RESULTS

Out of 239 assessable patients, 12 (5%) were coinfected with hepatitis B virus (HBV) and 34 (14.2%) with hepatitis C virus (HCV). The incidence rate of ALEE was 9.9/100 patients-year and the cumulative incidence was 20.9%. HCV genotype 3 tended to give a higher risk of ALEE. Independent factors for developing ALEE in multivariate logistic regression were HBV (HR = 4.0) and HCV (HR = 3.4) coinfections, antiretroviral therapy (HR = 2.6), CDC stage C (HR = 2.5), and high alkaline phosphatase baseline values (HR = 1.7).

CONCLUSION

The occurrence of ALEE is influenced more by the past medical history and the clinical background of the patients than by antiretroviral therapy. These patient-linked variables must be taken into account to avoid unwarranted treatment withdrawal.

Challenges in the Management of HIV and Hepatitis C Virus Co-infection

Hepatitis C virus (HCV) has become a significant contributor to morbidity and mortality to those infected with HIV since the introduction of highly active antiretroviral therapy (HAART). The presence of HIV clearly has a negative effect on the natural history of HCV, although there is some debate over whether HCV influences the natural history of HIV. Given the prevalence of co-infection and the accelerated liver damage from HCV, treatment of chronic HCV infection is an important consideration in patients co-infected with HIV. There are few studies of pegylated interferon and ribavirin in co-infected populations, but it seems that the treatment is well tolerated, although it is possibly less effective in this group. HAART in the setting of HCV infection also requires some special consideration, namely an increased incidence of hepatotoxicity. Treatment of co-infected patients requires close monitoring as current therapies are not ideal in terms of effectiveness, and toxicity may be severe.

Viral Load and CD4+ T Lymphocyte Response to Highly Active Antiretroviral Therapy in Human Immunodeficiency Virus Type 1-Infected Children: An Observational Study

An observational study was performed involving 95 children with vertically transmitted human immunodeficiency virus type 1 infection to assess the sustainability of undetectable viral loads (VLs) and increased CD4+ T lymphocyte percentages after 48 months of highly active antiretroviral therapy (HAART). The median time to achieve a 10% increase in the CD4+ T lymphocyte percentage was 11.01 months. The median time to achieve an undetectable VL was 6.4 months. At the end of the study, 64.2% of the children had achieved an undetectable VL. Of the patients with an initial VL of >3.6 log10 copies/mL, 74.7% had a decrease in the VL of 1 log10 copies/mL. By contrast, of the patients who presented with an initial VL of >4.6 log10 copies/mL, 37.9% had a decrease of >2 log10 copies/mL. Higher VL at baseline, antiretroviral therapy regimens received before HAART, and multiple drug switches while receiving antiretroviral therapy were all inversely associated with an undetectable VL. A CD4+ T lymphocyte percentage of >25% was directly associated with undetectable VL during the follow-up period. In conclusion, first-line HAART induces beneficial virological and immunological outcome responses in children.

Challenges facing health professionals caring for HIV-infected drug users

Although injection drug use accounts for only 5% to 10% of cumulative HIV infections globally, it is a more efficient way of spreading HIV than sexual intercourse. HIV epidemics among injection drug users (IDUs) have a potential for rapid spread of the virus within the IDU community and outward into the general population. Effective interventions addressing this mode of HIV transmission are needed because part of a comprehensive strategy to curb the spread of HIV infection. IDUs, often marginalized, pose serious health challenges that can no longer be overlooked. Health care providers need to familiarize themselves with these challenges in order to meet the needs of this disenfranchised population. Providers need to have a clear understanding of targeted behavior and their patients' environmental context. Efforts must be made to foster healthy behavior among IDUs to assist them in managing their infection effectively and become productive members of society. This paper reviews these challenges and outlines selected models that may assist health care providers in fostering behavior changes among HIV-positive injection drug users.

Correlation of single photon emission computed tomography parameters as a noninvasive alternative to liver biopsies in assessing liver involvement in the setting of HIV and hepatitis C virus coinfection: a multicenter trial of the Adult AIDS Clinical Trials Group

Performing a liver biopsy in patients infected with HIV and hepatitis C virus (HCV) is considered the standard of practice to assess hepatic involvement but carries risks to patients. This pilot study was designed to identify single photon emission computed tomography (SPECT) parameters that correlate with liver disease stage. HIV-coinfected and HCV-coinfected individuals undergoing a liver biopsy had a SPECT scan performed. The results showed that a number of SPECT parameters were associated with histologic changes in architecture, fibrosis, and cirrhosis, of which two SPECT parameters, the minimum pixel count for spleen region of interest and maximum pixel count for right hepatic lobe, correctly classified 39 of 46 SPECT/biopsy pairs. In conclusion, this pilot trial identified SPECT parameters that correlated with liver histology changes. A larger study is needed to demonstrate whether SPECT parameters alone or with other markers can provide information on fibrosis with the clinical significance obtained through liver biopsy.

A review of low-dose ritonavir in protease inhibitor combination therapy

The pharmacokinetics of protease inhibitors center around the microsomal enzyme cytochrome P-450 3A4. As a potent inhibitor of this enzyme, ritonavir can increase the bioavailability and half-life of coadministered protease inhibitors. Evidence suggests that increased exposure to protease inhibitors is clinically relevant. Antiretroviral treatment with low-dose ritonavir-boosted lopinavir, indinavir, and saquinavir has durable virological activity and shows impressive immune reconstitution. Although tolerable in most cases, gastrointestinal side effects, hepatotoxicity, and blood lipid abnormalities remain relevant issues. Additional study will elucidate the advantages and disadvantages of twice-daily, low-dose ritonavir-boosted regimens and determine whether once-daily regimens based on this principle will have a lasting role in clinical practice.

Antiretroviral-associated liver injury

ART-related hepatotoxicity can manifest in a variety of ways. Although benign, asymptomatic LEEs predominate, liver injury occurring in the context of either hypersensitivity or hyperlactatemia, represents a medical emergency and mandates immediate cessation of ART. Underpinning this broad spectrum of presentations are several, as yet poorly understood, mechanisms of liver damage that reflect contributions by constituents of HAART and host factors. Thus far, the most significant predisposing condition to emerge from clinical studies is chronic viral hepatitis. A more precise understanding, however, of the processes and factors that underlie ART-related hepatotoxicity is critical not only to the management of liver injury from current antiretroviral drugs but also to the design of safer drugs in the future.