Hepatotoxicity of Antiretrovirals

Nano-Selenium Modulates NF-κB/NLRP3 Pathway and Mitochondrial Dynamics to Attenuate Microplastic-Induced Liver Injury

BACKGROUND

Microplastics (PS-MPs) are a new type of pollutant with definite hepatotoxicity. Selenium, on the other hand, has natural, protective effects on the liver.

OBJECTIVES/METHODS

The purpose of this experiment is to find out whether nano-selenium (SeNP) can alleviate liver damage caused by microplastics. Initially, we established through in vitro experiments that SeNP has the ability to enhance the growth of healthy mouse liver cells, while microplastics exhibit a harmful impact on normal mouse hepatocyte cell suspensions, leading to a decrease in cell count. Subsequently, through in vivo experiments on male ICR mice, we ascertained that SeNPs alleviated the detrimental impacts of PS-MPs on mouse liver.

RESULTS

SeNPs hinder the signaling pathway of NF-κB/NLRP3 inflammatory vesicles, which is crucial for reducing inflammation induced by PS-MPs. In terms of their mechanism, SeNPs hinder the abnormalities in mitochondrial fission, biogenesis, and fusion caused by PS-MPs and additionally enhance mitochondrial respiration. This enhancement is crucial in averting disorders in energy metabolism and inflammation.

CONCLUSIONS

To summarize, the use of SeNPs hindered inflammation by regulating mitochondrial dynamics, thus relieving liver damage caused by PS-MPs in mice. The anticipated outcomes offer new research directions that can be referenced in terms of inflammatory injuries caused by PS-MPs.

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.

Acute hepatitis and acute liver failure: Pathologic diagnosis and differential diagnosis

Acute hepatitis and acute liver failure are severe medical conditions that require early clinical intervention. Histopathologic findings on a liver biopsy or a liver explant may help identify the underlying etiology or provide an important direction for further clinical, laboratory and radiographical investigation. This review is divided into two main portions. The first portion concentrates on various etiologies and discusses unique histologic features that can be associated with specific etiologies. The second portion describes the general morphologic features based on which the diagnosis of acute hepatitis and acute liver failure are made. Histopathologic distinction between collapse and cirrhosis and limitations of histopathologic assessment for underlying etiologies are addressed in this portion. Another focus of this review is non-necrotic acute liver failure, which typically features diffuse microvesicular steatosis secondary to various etiologies causing mitochondrial dysfunction. Molecular testing serves an increasingly important role in the diagnosis and management of this group of disorders.

Drug-drug interactions and clinical considerations with co-administration of antiretrovirals and psychotropic drugs

Psychotropic medications are frequently co-prescribed with antiretroviral therapy (ART), owing to a high prevalence of psychiatric illness within the population living with HIV, as well as a 7-fold increased risk of HIV infection among patients with psychiatric illness. While ART has been notoriously associated with a multitude of pharmacokinetic drug interactions involving the cytochrome P450 enzyme system, the magnitude and clinical impact of these interactions with psychotropics may range from negligible effects on plasma concentrations to life-threatening torsades de pointes or respiratory depression. This comprehensive review summarizes the currently available information regarding drug-drug interactions between antiretrovirals and pharmacologic agents utilized in the treatment of psychiatric disorders-antidepressants, stimulants, antipsychotics, anxiolytics, mood stabilizers, and treatments for opioid use disorder and alcohol use disorder-and provides recommendations for their management. Additionally, overlapping toxicities between antiretrovirals and the psychotropic classes are highlighted. Knowledge of the interaction and adverse effect potential of specific antiretrovirals and psychotropics will allow clinicians to make informed prescribing decisions to better promote the health and wellness of this high-risk population.

Hepatic and renal toxicity and associated factors among HIV-infected children on antiretroviral therapy: a prospective cohort study

OBJECTIVES

The aim of the study was to investigate the prevalence of renal function and liver enzyme abnormalities among HIV-infected children, changes in prevalence with time on combination antiretroviral therapy (cART), and the factors associated with these abnormalities.

METHODS

A prospective cohort study was conducted among HIV-infected children < 18 years old (n = 705) who were on first-line cART. Liver enzymes, renal function, haematology, immunology and virological response were assessed at enrolment and followed bi-annually for 18 months. Liver fibrosis and cirrhosis were assessed using noninvasive markers including the aspartate aminotransferase (AST) to platelet ratio index (APRI) and fibrosis score (FIB-4).

RESULTS

The median age was 12 [interquartile range (IQR) 8-14] years; 53.3% of patients were male. At enrolment, the median cART duration was 3.3 (IQR 1.1-6.1) years; 177 (25.1%) and 83 (11.8%) patients had elevated AST and alanine aminotransferase (ALT), respectively. A tenth of the children had an APRI score > 0.5, suggesting liver fibrosis. Being on a zidovudine (ZDV)- or nevirapine (NVP)-based regimen and having a viral load > 1000 HIV-1 RNA copies/mL were significantly associated with elevated ALT. Twenty-four (3.4%) and 84 (12.1%) patients had elevated creatinine and blood urea nitrogen (BUN), respectively. As cART duration increased by 6 months, median BUN increased by 1.6 [95% confidence interval (CI) 0.4-2.7] mg/dL (P = 0.01); the glomerular filtration rate (GFR) decreased by 35.6 (95% CI 17.7-53.4) mL/min/1.73 m² (P < 0.0001); and AST and ALT decreased by 1.4 (95% CI 0.4-2.5) IU/L (P = 0.01) and 1.4 (95% CI 0.2-2.6) IU/L (P = 0.01), respectively.

CONCLUSIONS

A high prevalence of liver enzyme and renal function abnormalities was observed at enrolment. Decreasing liver enzyme levels during follow-up are possibly reassuring, while the progressive reduction in GFR and the increase in BUN are worrisome and require further study.

Acute Care Management of the HIV-Infected Patient: A Report from the HIV Practice and Research Network of the American College of Clinical Pharmacy

OBJECTIVE

Patients infected with human immunodeficiency virus (HIV) admitted to the hospital have complex antiretroviral therapy (ART) regimens with an increased medication error rate upon admission. This report provides a resource for clinicians managing HIV-infected patients and ART in the inpatient setting.

METHODS

A survey of the authors was conducted to evaluate common issues that arise during an acute hospitalization for HIV-infected patients. After a group consensus, a review of the medical literature was performed to determine the supporting evidence for the following HIV-associated hospital queries: admission/discharge orders, antiretroviral hospital formularies, laboratory monitoring, altered hepatic/renal function, drug-drug interactions (DDIs), enteral administration, and therapeutic drug monitoring.

RESULTS

With any hospital admission for an HIV-infected patient, a specific set of procedures should be followed including a thorough admission medication history and communication with the ambulatory HIV provider to avoid omissions or substitutions in the ART regimen. DDIs are common and should be reviewed at all transitions of care during the hospital admission. ART may be continued if enteral nutrition with a feeding tube is deemed necessary, but the entire regimen should be discontinued if no oral access is available for a prolonged period. Therapeutic drug monitoring is not generally recommended but, if available, should be considered in unique clinical scenarios where antiretroviral pharmacokinetics are difficult to predict. ART may need adjustment if hepatic or renal insufficiency ensues.

CONCLUSIONS

Treatment of hospitalized patients with HIV is highly complex. HIV-infected patients are at high risk for medication errors during various transitions of care. Baseline knowledge of the principles of antiretroviral pharmacotherapy is necessary for clinicians managing acutely ill HIV-infected patients to avoid medication errors, identify DDIs, and correctly dose medications if organ dysfunction arises. Timely ambulatory follow-up is essential to prevent readmissions and facilitate improved transitions of care.

Camel milk and bee honey regulate profibrotic cytokine gene transcripts in liver cirrhosis induced by carbon tetrachloride

The lack of studies regarding the mechanism of the protective effects of camel milk and bee honey against hepatotoxic compounds led us to perform this study. Thirty-six male rats were divided into two main groups. The first group (n = 9) comprised control non-cirrhotic rats. The rats of the second group (n = 27) were administered carbon tetrachloride (CCl4) by intraperitoneal injection to induce liver cirrhosis. The cirrhotic rats were then divided into three equal subgroups, each comprising nine animals, as follows: (i) cirrhotic rats, (ii) cirrhotic rats treated with camel milk, and (iii) cirrhotic rats treated with camel milk and bee honey. The present findings revealed that CCl4elevated the activities of liver enzymes, blood glucose levels, non-esterified fatty acids (NEFA) in the serum and glycogen content in the liver. On the other hand, CCl4significantly decreased phosphorylase activity in the liver tissue and significantly increased carbohydrate intolerance and insulin resistance index (HOMA-IR). Moreover, CCl4induced a significant increase in oxidative stress, along with increased expression of the profibrotic cytokine genes TNF-α and TGF-β. However, camel milk either alone or in combination with bee honey ameliorated these toxic actions. The antioxidant properties of these protective agents and their effects of downregulating certain procirrhotic cytokine gene transcripts underlie this protection.

Acrolein enhances epigenetic modifications, FasL expression and hepatocyte toxicity induced by anti-HIV drug Zidovudine

Zidovudine (AZT) remains the mainstay of antiretroviral therapy against HIV in resource-poor countries; however, its use is frequently associated with hepatotoxicity. Not all HIV patients on AZT develop hepatotoxicity, and the determining factors are unclear. Alcohol consumption and cigarette smoking are known risk factors for HIV hepatotoxicity, and both are significant sources of acrolein, a highly reactive and toxic aldehyde. This study examines the potential hepatotoxic interactions between acrolein and AZT. Our data demonstrate that acrolein markedly enhanced AZT-induced transcriptionally permissive histone modifications (H3K9Ac and H3K9Me3) allowing the recruitment of transcription factor NF-kB and RNA polymerase II at the FasL gene promoter, resulting in FasL upregulation and apoptosis in hepatocytes. Notably, the acrolein scavenger, hydralazine prevented these promoter-associated epigenetic changes and inhibited FasL upregulation and apoptosis induced by the combination of AZT and acrolein, as well as AZT alone. Our data strongly suggest that acrolein enhancement of promoter histone modifications and FasL upregulation are major pathogenic mechanisms driving AZT-induced hepatotoxicity. Moreover, these data also indicate the therapeutic potential of hydralazine in mitigating AZT hepatotoxicity.

Impact of Obliterative Portal Venopathy Associated With Human Immunodeficiency Virus

HIV-associated obstructive portopathy (HIVOP) is an obstruction of the hepatic microvasculature of unknown origin. The purpose of this study was to describe the clinical and paraclinical presentation of the disease and its impact in terms of morbidity. Twenty-nine HIV1-infected patients (average 12 years of infection, nadir of CD4 210/mm, including 7 patients with a history of opportunistic infection) with a biopsy-proven or likely HIVOP have been followed up for an average of 6.1 years. Modes of revelation of the HIVOP were: cytolysis and/or cholestasis (60%), occult (14%) or symptomatic (37%) portal hypertension (esophageal varices 17%, ascites 10%, cytopenia 10%), or fortuitous (8%). Hypoalbuminemia (≤35 g/L) was present in (31%), thrombocytopenia (<150,000 platelets) in 52% and prothrombin rate <70% in 10%. Esophageal varices were detected in 71%. Thrombophilia was present in 23 patients (80%): in head, protein S deficiency (87%). MRI showed in 82% at least 1 morphological abnormality. The average value of the liver stiffness by Fibroscan was 8.3 kPa. During follow-up, there was no radiological improvement, 15 (52%) patients presented with variceal hemorrhage, 10 patients (34%) ascites, 10 (34%) portal vein thrombosis, 7 (24%) an iron deficiency, and 2 (7%) with a protein-losing enteropathy, including 14 patients (48%) with several events. Four patients (14%) were transplanted, 1 (25%) recurred the HIVOP on the graft, and 1 patient is waiting for a transplant. HIVOP is a severe disease associated with high morbidity related to symptomatic portal hypertension, which occurred in 50% and required liver transplantation in 14%.

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.

A clinicopathological cohort study of liver pathology in 301 patients with human immunodeficiency virus/acquired immune deficiency syndrome

Liver disease complicates human immunodeficiency virus (HIV)/acquired immune deficiency syndrome; however, liver pathology data are limited, particularly from high HIV prevalence countries. We investigated the spectrum and clinicopathological correlates of liver pathology in a high HIV burden setting. In a single-center study, all HIV/acquired immune deficiency syndrome patients with complete clinical and demographic data who underwent liver biopsy were analyzed and clinicopathologically assessed by hepatologists and one of two experienced liver pathologists. We evaluated 301 patients, with a median age of 34 (interquartile range 29-40) years. Women (n = 143) were younger than men (n = 158), with a median age of 33 (interquartile range 28-37) versus 35 (interquartile range 31-41) years, P = 0.001. The majority, 76.1%, were black African. Median CD4 at time of biopsy was 127 (52-260) cells/mm(3) . Drug-induced liver injury was the predominant finding (42.2%), followed by granulomatous inflammation (29%), steatosis/steatohepatitis (19.3%), hepatitis B (19%), and hepatitis C coinfection (3.3%), with more than one pathology in 16.2%. With granulomatous inflammation, 52% met the criteria for tuberculosis immune reconstitution syndrome. By univariate analysis, cotrimoxazole and antiretroviral therapy conferred risk for drug injury (odds ratio [OR] = 2.78 [1.72-4.48], P < 0.001; OR = 1.69 [1.06-2.68], P = 0.027). In multivariate analysis, cotrimoxazole was associated with a cholestatic or ductopenic injury (OR = 7.05 [2.50-19.89], P < 0.001; OR = 17.6 [3.26-95.3], P < 0.0001); efavirenz was associated with nonspecific hepatitis or submassive necrosis (OR = 4.3 [1.92-9.83], P < 0.001; OR = 10.46 [2.7-40.5], P < 0.001). Cholestatic injury was associated with female gender and a CD4 of >200 cells/mm(3) , and submassive necrosis was associated with younger age. Hepatitis B demonstrated no association.

CONCLUSION

In a high HIV burden area, drug-induced liver injury due to antiretroviral therapy and cotrimoxazole was a frequent clinicopathological finding; Mycobacterium tuberculosis was the leading opportunistic infection, with more than half of patients fulfilling criteria for tuberculosis immune reconstitution syndrome; liver biopsy remains a useful diagnostic procedure in this setting.

Liver enzyme elevation during darunavir-based antiretroviral treatment in HIV-1-infected patients with or without hepatitis C coinfection: data from the ICONA foundation cohort

OBJECTIVES

To investigate differences in liver enzyme elevation (LEE) between HIV-infected patients with and without HCV coinfection who start a darunavir/ritonavir-containing regimen.

METHODS

HIV-infected patients enrolled in the Italian Cohort of Naïve to Antiretrovirals (ICONA) Foundation Study were included if they started darunavir/ritonavir for the first time. Patients were classified as not HCV coinfected, HCV active coinfected (HCV RNA positive), and HCV nonactive coinfected (HCV-Ab positive/HCV RNA negative). Time to LEE endpoint was defined using the ACTG toxicity scale, based on changes relative to baseline. Kaplan-Meier was used to estimate 1-year and 2-year probability of LEE. The incidence rate ratios (IRRs) of LEEs were estimated until the last follow-up (intention-to-treat analysis [ITT]) and up to darunavir/ritonavir discontinuation (on-treatment analysis [OT]).

RESULTS

Overall, 703 patients were included. Ninety-one were HCV-Ab positive; of those, 68 (9.7%) had active HCV coinfection. In 879 person-years of follow-up, 101 LEEs occurred (ITT). No severe hepatotoxicity event was registered in active HCV coinfected patients. HCV active coinfection was predictive of LEE in the overall population (OT: adjusted incidence rate ratio (IRR), 2.25; 95% CI, 0.70-7.24; P = .17; ITT: adjusted IRR, 3.62; 95% CI, 1.67-7.83; P < .001) and in naïve patients (OT: adjusted IRR, 6.29; 95% CI, 2.54-15.55; P = .00; ITT: adjusted IRR, 3.87; 95% CI, 0.99-15.16; P = .05).

CONCLUSIONS

No grade 3-4 LEEs occurred in HCV active coinfected patients. HCV active coinfected patients experienced low grade LEEs more frequently than HCV-Ab negative patients. Darunavir/ritonavir seems to be safe whatever the HCV status, when liver enzymes are carefully monitored.

Costs of adverse events among patients with HIV infection treated with nonnucleoside reverse transcriptase inhibitors

OBJECTIVES

The aim of the study was to assess the incidence and costs of adverse events (AEs) among patients with HIV infection treated with nonnucleoside reverse transcriptase inhibitors (NNRTIs) from the health care system perspective.

METHODS

US medical and pharmacy claims during 2004-2009 were examined to select adult new NNRTI users with HIV infection. The incidence of selected AEs and time to occurrence were assessed during the first year. Episodes of care for each AE were identified using claims associated with AE management. For each AE, a propensity score model was used to match patients with an AE to those without (1:4) based on the propensity of having an AE. Mean total health care costs, AE-associated costs and incremental costs per episode, and annual total health care costs per patient were calculated.

RESULTS

Of the 2548 NNRTI-treated patients, 29.3% experienced AEs. The incidence ranged from 0.4 episodes/1000 person-years for suicide/self-injury to 14.9 episodes/1000 person-years for dizziness, 49.8 episodes/1000 person-years for depression and 150.3 episodes/1000 person-years for lipid disorder. The mean AE-associated cost (duration) per episode ranged from $586 (88 days) for lipid disorder to $975 (33 days) for rash, $2760 (73 days) for sleep-related symptoms and $4434 (41 days) for nausea/vomiting. The mean incremental cost per episode ranged from $1580 for rash to $2032 for lipid disorder, $8307 for sleep-related symptoms and $12 833 for nausea/vomiting. During the 12 months following NNRTI initiation, the mean annual total health care cost was $27 299 (efavirenz: $26 185; other NNRTIs: $34 993) and AE-associated costs were $608 (efavirenz: $554; other NNRTIs: $979) among all NNRTI users.

CONCLUSIONS

With treatment increasing patient survival, comparisons of therapeutic regimens should consider treatment-associated AEs. Findings from this study could be informative for clinicians and payers in managing HIV infection with NNRTIs.

Management of HIV and hepatitis C virus infections in resource-limited settings

PURPOSE OF REVIEW

To provide an update on the epidemiology and management of HIV and hepatitis C virus (HCV) in resource-limited settings (RLSs).

RECENT FINDINGS

The global prevalence of HIV is 33.3 million people of whom 22.5 million live in sub-Saharan Africa. Hepatitis C affects 170 million people globally with majority of the infected persons living in sub-Saharan Africa and other RLSs. Transmission of these viruses varies greatly even within the RLSs. In the RLSs in Europe, Asia and Central/South America, most transmissions occur through injection drug use, whereas in Africa use of needles for medical treatment and blood transfusion may be the main modes of transmission. However, generally there is a rise in injection drug use even in RLSs.

SUMMARY

Hepatitis C and HIV are common infections and are more prevalent in RLSs, but there are regional differences in transmission even in RLSs. Treatment is difficult in some of the RLSs and prevention by screening donor blood as well and use of sterile instruments in treatment of patients will be important in curbing transmission in some of these settings.

[Human immunodeficiency virus infection and viral hepatitis]

Hepatic complications currently represent one of the leading reasons for medical consultations, hospitalisation, and death in the HIV-infected population. This is due to a large extent to viral hepatitis, given its disproportionate frequency in this population. Chronic hepatitis B affects 5-10% of the HIV-infected population. Vaccination has reduced the incidence of liver disease related to hepatitis-B virus (HBV), and the availability of tenofovir has dramatically improved the prognosis of HIV/HBV carriers. Delta hepatitis affects around 15% of HIV-infected individuals in Europe harbouring positive HBsAg. It has the worst prognosis, given its accelerated course to cirrhosis and the absence of successful therapy. Lastly, chronic hepatitis C is the major cause of liver disease in the HIV population. Although classically linked to persons infected parenterally (i.e., intravenous drug users), outbreaks of acute hepatitis C among homosexual men have been reported over the last decade. Treatment with pegylated interferon plus ribavirin provides a cure in less than 40% of patients. However, the introduction of new direct acting antivirals against hepatitis- C virus (HCV) (telaprevir, boceprevir) has revolutionised the field, as HAART did in 1996 in the HIV field, improving the prognosis of co-infected patients. However, interactions between these drugs and antiretroviral agents and the risk of selective resistance pose huge threats in this population.

Hepatitis B in pregnancy: challenges and treatment

Hepatitis B virus (HBV) during pregnancy presents unique management challenges. Varying aspects of care must be considered, including the effects of HBV on maternal and fetal health, effects of pregnancy on the course of HBV infection, treatment of HBV during and after pregnancy, and prevention of perinatal infection. Antiretroviral therapy has not been associated with increased risk of birth defects or toxicity, but despite studies designed to elucidate the drug efficacy and safety in affected individuals and the developing fetus, recommendations are inconclusive. Clinicians and patients must make individualized decisions after carefully evaluating the risks and benefits summarized in this article.

Transient elastography: a non-invasive tool for assessing liver fibrosis in HIV/HCV patients

AIM

To assess the prevalence of advanced liver fibrosis (ALF) in human immunodeficiency virus (HIV), hepatitis C virus (HCV) and HIV/HCV patients using transient elastography, and to identify factors associated with ALF.

METHODS

Between September 2008 and October 2009, 71 HIV mono-infected, 57 HIV/HCV co-infected and 53 HCV mono-infected patients on regular follow-up at our Center were enrolled in this study. Alcohol intake, the main parameters of liver function, presence of HCV-RNA, HIV-RNA, duration of highly active anti-retroviral therapy (HAART) and CD4 cell count were recorded. ALF was defined as liver stiffness (LS) ≥ 9.5 kPa. To estimate liver fibrosis (LF) a further 2 reliable biochemical scores, aspartate aminotransferase platelet ratio index (APRI) and FIB-4, were also used.

RESULTS

LS values of co-infected patients were higher than in either HIV or HCV mono-infected patients (χ(2)(MH) = 4, P < 0.04). In fact, LS ≥ 9.5 was significantly higher in co-infected than in HIV and HCV mono-infected patients (χ(2) = 5, P < 0.03). Also APRI and the FIB-4 index showed more LF in co-infected than in HIV mono-infected patients (P < 0.0001), but not in HCV mono-infected patients. In HIV⁄HCV co-infected patients, the extent of LS was significantly associated with alcohol intake (P < 0.04) and lower CD4+ cell count (P < 0.02). In HCV patients, LS was correlated with alcohol intake (P < 0.001) and cholesterol levels (P < 0.03). Body mass index, diabetes, HCV- and HIV-viremia were not significantly correlated with LS. In addition, 20% of co-infected patients had virologically unsuccessful HAART; in 50% compliance was low, CD4+ levels were < 400 cells/mm(3) and LS was > 9.5 kPa. There was no significant correlation between extent of LF and HAART exposure or duration of HAART exposure, in particular with specific dideoxynucleoside analogues.

CONCLUSION

ALF was more frequent in co-infected than mono-infected patients. This result correlated with lower CD4 levels. Protective immunological effects of HAART on LF progression outweigh its hepatotoxic effects.

Incidence of Severe Hepatotoxicity Related to Antiretroviral Therapy in HIV/HCV Coinfected Patients

Introduction. Hepatotoxicity is a concern in HIV/hepatitis C virus (HCV) coinfected patients due to their underlying liver disease. This study assessed the incidence of hepatotoxicity in HIV/HCV co-infected patients in two outpatient infectious diseases clinics. Methods. HIV/HCV co-infected adults were included in this retrospective study if they were PI or NNRTI naïve at their first clinic visit and were initiated on an NNRTI- and/or PI-based antiretroviral regimen. Patients were excluded if they had active or chronic hepatitis B virus (HBV). The primary objective was to determine the overall incidence of severe hepatotoxicity. Results. Fifty-six of the 544 patients identified met inclusion criteria. The incidence of severe hepatotoxicity was 10.7% (6/56 patients). Severe hepatotoxicity occurred with efavirenz (N = 2), nevirapine (N = 1), indinavir (N = 1), nelfinavir (N = 1), and saquinavir/ritonavir (N = 1). Conclusion. The incidence of severe hepatotoxicity appears to be low in this retrospective analysis of HIV/HCV co-infected patients receiving a PI-and/or NNRTI-based regimen.

Clinical syndromes and consequences of antiretroviral-related hepatotoxicity

Highly active antiretroviral therapy (HAART)-related hepatotoxicity complicates the management of patients infected with human immunodeficiency virus (HIV), increases medical costs, alters the prescription patterns, and affects the guideline recommendations. Among the clinical consequences derived from HAART-related liver toxicity, hypersensitivity reactions and lactic acidosis are recognized as acute events with potential to evolve into fatal cases, whereas there seems to be other syndromes not as well characterized but of equal concern as possible long-term liver complications. Belonging to the latter category of syndrome, HAART-related nonalcoholic steatohepatitis, liver fibrosis, portal hypertension, and nodular regenerative hyperplasia are discussed in this review. Updated information on liver toxicity of current antiretroviral drugs, including the most recently licensed, is provided. Management and prevention of liver toxicity among HIV-infected patients treated with HAART are reviewed as well.

Low rates of hepatotoxicity in HIV-infected children on anti-retroviral therapy with and without isoniazid prophylaxis

This study investigates the incidence of hepatotoxicity in HIV-infected children during anti-retroviral therapy (ART) and the impact of concomitant use of isoniazid preventive therapy. It is a retrospective cohort analysis of HIV-infected children who commenced ART or were followed up between September 1998 and November 2005. Alanine transferase levels were measured at baseline, at 1, 3 and 6 months and then 6 monthly thereafter. Of the 598 children included in the study, 425 were taking ART alone, 73 ART and isoniazid, 39 isoniazid alone and 61 neither isoniazid nor ART. There was no increased risk of hepatotoxicity with ART with or without isoniazid compared to the control group over a 2-year period. Grade 3 or 4 ALT elevations occurred in 19 (3.4%) children, with no cases of fulminant hepatic failure. Severe hepatic events are uncommon in children on ART or isoniazid. There is no increased risk of hepatotoxicity with ART and concurrent isoniazid preventive therapy.

Effects of hepatic impairment on the steady-state pharmacokinetics of etravirine 200 mg BID: an open-label, multiple-dose, controlled Phase I study in adults

BACKGROUND

Etravirine is a non-nucleoside reverse transcriptase inhibitor (NNRTI) with activity against both wild-type HIV and viruses harboring NNRTI resistance. Etravirine is mainly eliminated via the hepatobiliary route.

OBJECTIVES

This study in HIV- patients with mild or moderate hepatic impairment and healthy matched controls was conducted to explore the effects of mild and moderate hepatic impairment on the steady-state pharmacokinetics of etravirine and to provide guidance for the treatment of HIV+ patients with hepatic impairment.

METHODS

This open-label, multiple-dose study enrolled HIV- patients aged 18 to 65 years with mild or moderate hepatic impairment (Child-Pugh score, 5-6 or 7-9, respectively) and healthy volunteers matched for age, sex, race, and body mass index (BMI). All subjects received etravirine 200 mg BID with food for 7 days and a morning dose on day 8. Etravirine pharmacokinetics over a period of 12 hours on days 1 and 8 were determined using noncompartmental methods and analyzed using linear mixed-effects modeling. Tolerability of etravirine was assessed based on the reported adverse events, laboratory investigations, ECG, and physical examination.

RESULTS

Each group comprised 8 subjects (mild hepatic impairment patients: 5 men, 3 women; median age, 57 years [range, 41-65 years]; BMI, 26 kg/m(2) [range, 20-32 kg/m(2)]; moderate hepatic impairment patients: 6 men, 2 women; age, 54 years [range, 44-64 years]; BMI, 26 kg/m(2) [range, 22-32 kg/m(2)]). All patients were white and light smokers. On day 8, the least squares mean ratios (90% CIs) of the log transformed pharmacokinetic properties in patients with mild and moderate hepatic impairment were, respectively: C(min), 0.87 (0.65-1.17) and 0.98 (0.68-1.42) microg/mL; C(max), 0.79 (0.63-1.00) and 0.72 (0.54-0.96) ug/mL; and AUC(0-12), 0.87 (0.69-1.09) and 0.82 (0.60-1.11) microg/mL/h. All treatment-emergent adverse events were considered mild to moderate; the most common were headache (50% in healthy controls) and fatigue and nausea (both 25% in patients with mild hepatic impairment). No clinically significant changes in laboratory parameters, physical examination including vital signs, or ECG were observed. One serious adverse event was reported during the follow-up period in a patient with moderate hepatic impairment due to hepatic cirrhosis secondary to alcoholism. This patient presented at screening with dilated cardiomyopathy and cardiac arrhythmia.

CONCLUSIONS

In this Phase I pharmacokinetic study, no clinically relevant differences were observed between patients with mild or moderate hepatic impairment and healthy matched subjects with regard to the pharmacokinetics of etravirine. Based on these findings in these HIV- volunteers, no dose adjustment of etravirine appears to be necessary in patients with mild or moderate hepatic impairment. Etravirine was generally well tolerated.

Metabolic and hepatobiliary side effects of antiretroviral therapy (ART)

Although antiretroviral therapy (ART) for human immunodeficiency virus (HIV) has been in use since 1987, the initiation of highly active ART has produced an increase in adverse drug reactions. This is a new challenge as many of the adverse drug reactions attributable to ART may be indistinguishable from non-drug-related illnesses. The emergency physician must be aware of the potential complications of ART as affected patients may present with nonspecific symptoms. The focus of this article is the metabolic and hepatobiliary adverse effects of ART.

[Adverse reactions of atazanavir, fosamprenavir and tipranavir in "real life"]

OBJECTIVE

To precise adverse effects of atazanavir, fosamprenavir and tipranavir "in real life".

METHOD

Descriptive study of 3 protease inhibitor adverse effects stored in the French Bank of Pharmacovigilance.

RESULTS

Nineteen adverse effects having at least possible links with antiretroviral drugs studied were reported. It was essentially hepatobiliary (atazanavir: 29/59, tipranavir: 4/6) and skin (fosamprenavir: 10/20) adverse reactions. These reactions, relatively "serious" (35.1%) led to the interruption of the person (or persons) medication (s) suspected (s) in 69 folds (82.1%) and evolved to healing without sequelae in 68 folds (81%).

CONCLUSION

The drug side effects were for the most expected. However, their frequency and their seriously underline the interest of a post-AMM monitoring to reassess the drugs risk-benefit report.

[Etravirine in special populations]

The choice of antiretroviral treatment in comorbidities requires thorough knowledge of the interactions, pharmacokinetics and adverse effects of the drug to be used. Most drugs carry some risk in certain processes associated or not with HIV infection and drugs that can be used in these situations are of great interest. The development of etravirine, a new non-nucleoside reverse transcriptase inhibitor, will allow its use in these processes, with a lower risk of secondary effects and therefore of worsening the course of the disease and of treatment withdrawal. This is the case of patients coinfected with active hepatitis B and/or C virus and patients with a history of psychiatric disorders or receiving psychotropic drugs. The possible use of etravirine in women of fertile age is also of interest, due to the lower risk of teratogenicity if pregnancy occurs during treatment. Other collectives, such as patients with renal insufficiency or children and adolescents should not be forgotten; although these populations are less well studied, data are beginning to become available.

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.

Mechanism-based bioanalysis and biomarkers for hepatic chemical stress

Adverse drug reactions, in particular drug-induced hepatotoxicity, represent a major challenge for clinicians and an impediment to safe drug development. Novel blood or urinary biomarkers of chemically-induced hepatic stress also hold great potential to provide information about pathways leading to cell death within tissues. The earlier pre-clinical identification of potential hepatotoxins and non-invasive diagnosis of susceptible patients, prior to overt liver disease is an important goal. Moreover, the identification, validation and qualification of biomarkers that have in vitro, in vivo and clinical transferability can assist bridging studies and accelerate the pace of drug development. Drug-induced chemical stress is a multi-factorial process, the kinetics of the interaction between the hepatotoxin and the cellular macromolecules are crucially important as different biomarkers will appear over time. The sensitivity of the bioanalytical techniques used to detect biological and chemical biomarkers underpins the usefulness of the marker in question. An integrated analysis of the biochemical, molecular and cellular events provides an understanding of biological (host) factors which ultimately determine the balance between xenobiotic detoxification, adaptation and liver injury. The aim of this review is to summarise the potential of novel mechanism-based biomarkers of hepatic stress which provide information to connect the intracellular events (drug metabolism, organelle, cell and whole organ) ultimately leading to tissue damage (apoptosis, necrosis and inflammation). These biomarkers can provide both the means to inform the pharmacologist and chemist with respect to safe drug design, and provide clinicians with valuable tools for patient monitoring.

Antiretroviral treatment of HIV infection: Swedish recommendations 2007

On 3 previous occasions, in 2002, 2003 and 2005, the Swedish Medical Products Agency (Läkemedelsverket) and the Swedish Reference Group for Antiviral Therapy (RAV) have jointly published recommendations for the treatment of HIV infection. An expert group, under the guidance of RAV, has now revised the text again. Since the publication of the previous treatment recommendations, 1 new drug for the treatment of HIV has been approved - the protease inhibitor (PI) darunavir (Prezista). Furthermore, 3 new drugs have become available: the integrase inhibitor raltegravir (MK-0518), the CCR5-inhibitor maraviroc (Celsentri), both of which have novel mechanisms of action, and the non-nucleoside reverse transcriptase inhibitor (NNRTI) etravirine (TMC-125). The new guidelines differ from the previous ones in several respects. The most important of these are that abacavir is now preferred to tenofovir and zidovudine, as a first line drug in treatment-naïve patients, and that initiation of antiretroviral treatment is now recommended before the CD4 cell count falls below 250/microl, rather than 200/microl. Furthermore, recommendations on the treatment of HIV infection in children have been added to the document. As in the case of the previous publication, recommendations are evidence-graded in accordance with the Oxford Centre for Evidence Based Medicine, 2001 (see http://www.cebm.net/levels_of_evidence.asp#levels).

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.

Drug-Induced Liver Injury Network (DILIN) prospective study: rationale, design and conduct

BACKGROUND

Drug-induced liver injury (DILI) is an uncommon adverse drug reaction of increasing importance to the medical community, pharmaceutical industry, regulatory agencies and the general public.

OBJECTIVES

The Drug-Induced Liver Injury Network (DILIN) was established to advance understanding and research into DILI by initiating a prospective registry of patients with bona fide DILI for future studies of host clinical, genetic, environmental and immunological risk factors. The DILIN was also charged with developing standardized nomenclature, terminology and causality assessment instruments.

METHODS

Five clinical sites, a data coordinating centre and senior scientists from the National Institute of Diabetes and Digestive and Kidney Diseases initiated the DILIN prospective study in September 2004. Eligible patients are required to meet minimal laboratory or histological criteria within 6 months of DILI onset and have other competing causes of liver injury excluded. Patients in the general community setting with pre-existing HIV, hepatitis B virus or hepatitis C virus infections and/or abnormal baseline liver biochemistries are eligible for enrollment. In addition, subjects with liver injury due to herbal products are eligible to participate. Control patients without DILI are also to be recruited in the future.

RESULTS

All referred subjects undergo an extensive review of available laboratory, pathology and imaging studies. Subjects who meet pre-defined eligibility criteria at the 6-month study visit are followed for 2 years to better define the natural history of chronic DILI. Causality assessment is determined by a panel of three hepatologists who independently assign a causality score ranging from 1 (definite) to 5 (unlikely) as well as a severity score ranging from 1 (mild) to 5 (fatal). During the first 3 years, 367 subjects were enrolled into the DILIN prospective study.

CONCLUSION

DILIN is a multicentre research network charged with improving our understanding of the aetiologies, risk factors and outcomes of DILI in the US. The network is meeting the targeted enrollment of ten patients per month and is developing a repository of clinical data and biological samples for future studies of DILI pathogenesis and outcome.

Drug-Induced Liver Injury Network (DILIN) prospective study: rationale, design and conduct

BACKGROUND

Drug-induced liver injury (DILI) is an uncommon adverse drug reaction of increasing importance to the medical community, pharmaceutical industry, regulatory agencies and the general public.

OBJECTIVES

The Drug-Induced Liver Injury Network (DILIN) was established to advance understanding and research into DILI by initiating a prospective registry of patients with bona fide DILI for future studies of host clinical, genetic, environmental and immunological risk factors. The DILIN was also charged with developing standardized nomenclature, terminology and causality assessment instruments.

METHODS

Five clinical sites, a data coordinating centre and senior scientists from the National Institute of Diabetes and Digestive and Kidney Diseases initiated the DILIN prospective study in September 2004. Eligible patients are required to meet minimal laboratory or histological criteria within 6 months of DILI onset and have other competing causes of liver injury excluded. Patients in the general community setting with pre-existing HIV, hepatitis B virus or hepatitis C virus infections and/or abnormal baseline liver biochemistries are eligible for enrollment. In addition, subjects with liver injury due to herbal products are eligible to participate. Control patients without DILI are also to be recruited in the future.

RESULTS

All referred subjects undergo an extensive review of available laboratory, pathology and imaging studies. Subjects who meet pre-defined eligibility criteria at the 6-month study visit are followed for 2 years to better define the natural history of chronic DILI. Causality assessment is determined by a panel of three hepatologists who independently assign a causality score ranging from 1 (definite) to 5 (unlikely) as well as a severity score ranging from 1 (mild) to 5 (fatal). During the first 3 years, 367 subjects were enrolled into the DILIN prospective study.

CONCLUSION

DILIN is a multicentre research network charged with improving our understanding of the aetiologies, risk factors and outcomes of DILI in the US. The network is meeting the targeted enrollment of ten patients per month and is developing a repository of clinical data and biological samples for future studies of DILI pathogenesis and outcome.

Drug-Induced Liver Injury Network (DILIN) prospective study: rationale, design and conduct

BACKGROUND

Drug-induced liver injury (DILI) is an uncommon adverse drug reaction of increasing importance to the medical community, pharmaceutical industry, regulatory agencies and the general public.

OBJECTIVES

The Drug-Induced Liver Injury Network (DILIN) was established to advance understanding and research into DILI by initiating a prospective registry of patients with bona fide DILI for future studies of host clinical, genetic, environmental and immunological risk factors. The DILIN was also charged with developing standardized nomenclature, terminology and causality assessment instruments.

METHODS

Five clinical sites, a data coordinating centre and senior scientists from the National Institute of Diabetes and Digestive and Kidney Diseases initiated the DILIN prospective study in September 2004. Eligible patients are required to meet minimal laboratory or histological criteria within 6 months of DILI onset and have other competing causes of liver injury excluded. Patients in the general community setting with pre-existing HIV, hepatitis B virus or hepatitis C virus infections and/or abnormal baseline liver biochemistries are eligible for enrollment. In addition, subjects with liver injury due to herbal products are eligible to participate. Control patients without DILI are also to be recruited in the future.

RESULTS

All referred subjects undergo an extensive review of available laboratory, pathology and imaging studies. Subjects who meet pre-defined eligibility criteria at the 6-month study visit are followed for 2 years to better define the natural history of chronic DILI. Causality assessment is determined by a panel of three hepatologists who independently assign a causality score ranging from 1 (definite) to 5 (unlikely) as well as a severity score ranging from 1 (mild) to 5 (fatal). During the first 3 years, 367 subjects were enrolled into the DILIN prospective study.

CONCLUSION

DILIN is a multicentre research network charged with improving our understanding of the aetiologies, risk factors and outcomes of DILI in the US. The network is meeting the targeted enrollment of ten patients per month and is developing a repository of clinical data and biological samples for future studies of DILI pathogenesis and outcome.

Hepatitis B virus infection and response to antiretroviral therapy (ART) in a South African ART program

BACKGROUND

Coinfection with hepatitis B virus (HBV) and human immunodeficiency virus (HIV) is common in Africa; however, the impact of HBV infection on the outcomes of antiretroviral therapy programs is unclear. We evaluated the impact of chronic hepatitis B on HIV virologic response, changes in CD4 cell count, hepatotoxicity, and mortality among Africans receiving highly active antiretroviral therapy (HAART).

METHODS

We conducted a retrospective cohort study involving a workplace HAART program in South Africa. Participants received HAART according to a protocol and were followed up for up to 72 weeks. On the basis of pre-HAART serum assays, patients were classified as being hepatitis B surface antigen (HBsAg) negative, HBsAg positive with a low HBV DNA level (</= 1 x 10(4) copies/mL), and HBsAg positive with a high HBV DNA level (> 1 x 10(4) copies/mL). The relationships between HBV status and HIV RNA suppression, change in CD4 cell count, mortality, and hepatotoxicity were assessed with use of regression techniques.

RESULTS

Five hundred thirty-seven individuals fulfilled the inclusion criteria; 431 (80.3%) of these patients were HBsAg negative, 60 (11.2%) were HBsAg positive with a low HBV DNA level, and 46 (8.6%) were HBsAg positive with a high HBV DNA level. All groups had similar rates of HIV RNA suppression (P = .61), CD4 cell count increases (P =.75), and mortality (17 total deaths; P=.11) for up to 72 weeks after the initiation of HAART. Baseline transaminase levels were highest in the group with high HBV DNA levels (P=.004). Hepatotoxicity was similar between the HBsAg-negative group and the group with low HBV DNA levels but was higher in the group with high HBV DNA levels (incidence rate ratio, 4.4).

CONCLUSIONS

We revealed that HBV status does not affect HIV RNA suppression, CD4 cell count response, or mortality during the first 72 weeks of HAART in an African setting. The risk of HBV-associated hepatotoxicity, however, is associated with the baseline HBV DNA level.

Review article: The use of potentially hepatotoxic drugs in patients with liver disease

BACKGROUND

Misconceptions surround the use of hepatotoxic drugs in chronic liver disease. While many prescription and over-the-counter (OTC) agents can be used safely, this often runs counter to labelled warnings/contraindications, especially for the statins and other commonly used agents.

AIM

To evaluate published data on the use of hepatotoxic drugs in chronic liver disease including pharmacokinetic changes in cirrhosis and drug interactions, where available, to formulate recommendations on their use.

METHODS

Using a combination of PubMed searches, review texts, the Physicians' Desk Reference and expert opinion, drugs considered at higher risk of hepatotoxicity in chronic liver disease were evaluated.

RESULTS

Most drugs and OTC products including herbals have not been formally studied in chronic liver disease, but available data suggest that several of the most commonly used agents, especially the statins, can be used safely. While there is an increased risk of drug-induced liver injury for drugs used in the treatment of tuberculosis and HIV patients with hepatitis B or C, recommendations for their safe use are emerging.

CONCLUSIONS

Although many clinicians remain hesitant to use hepatotoxic drugs in chronic liver disease, the database supporting this view is limited to just a few agents. Most medications can be used safely in patients with chronic liver disease with appropriate monitoring.

Hepatic ultrastructural mitochondrial changes prior to antiretroviral therapy in HIV-infected patients in Brazil

The use of antiretroviral (ARV) medications has been linked to the emergence of severe adverse effects, including mitochondrial toxicity. The liver also appears to be among the affected organs. Nevertheless, different studies suggest that these patients' mitochondrial alterations could be associated to other etiological factors. The goal of this study was to analyze hepatic mitochondria ultrastructural changes in HIV-infected patients under investigation for hepatopathy. Semiquantitative analysis of mitochondria was performed in liver biopsies from 10 patients divided into 2 groups: Group 1 consisted of 5 patients who had never used ARV medications; group 2 consisted of 5 patients who reported previous use of either zidovudine or didanosine. Significant mitochondrial alterations were found in both groups. The summation of the mitochondrial alterations was higher in group 1 (P < .05) when compared with those who had previously used ARV medications. Therefore, the authors conclude that severe mitochondrial alterations occur in HIV-infected patients who have never been submitted to antiretroviral therapy.

Liver cirrhosis in HIV-infected patients: prevalence, aetiology and clinical outcome

Liver disease is frequently seen in HIV+ patients as a result of coinfection with hepatitis B (HBV) or C (HCV) viruses, alcohol abuse and/or exposure to hepatotoxic drugs. The aim of this study was to assess the prevalence of liver cirrhosis, its main causes and clinical presentation in HIV+ patients. Observational, cross-sectional, retrospective study of all HIV+ individuals followed at one reference HIV outpatient clinic in Madrid. Liver fibrosis was measured in all cases using transient elastometry (FibroScan). All 2168 HIV+ patients on regular follow-up (76% males, 46% injecting drug users) were successfully examined by FibroScan) between October 2004 and August 2006. Liver cirrhosis was recognized in 181 (overall prevalence, 8.3%), and the main aetiologies were HCV, 82.3%; HBV, 1.6%; dual HBV/HCV, 2.8%; and triple HBV/HCV/ hepatitis delta virus (HDV) infection, 6.6%. The prevalence of cirrhosis differed among patients with distinct chronic viral hepatitis: HCV, 19.2%; HBV, 6.1%; HBV/HCV, 41.7%; and HBV/HCV/HDV, 66.7%. In 12 patients with cirrhosis (6.7%), no definite aetiology was recognized. Overall, cirrhotics had lower mean CD4 counts than noncirrhotics (408 vs 528 cells/microL respectively; P = 0.02), despite similar proportion of subjects with undetectable viraemia on highly active antiretroviral therapy. Clinical manifestations of liver cirrhosis were: splenomegaly, 61.5%; oesophageal varices, 59.8%; ascites, 22.6%; encephalopathy, 12.1%; and variceal bleeding, 6.1%. Liver cirrhosis and hepatic decompensation events are relatively frequent in HIV+ individuals. Chronic HCV and alcohol abuse, but not chronic HBV, play a major role. Transient elastometry may allow the identification of a significant number of HIV+ individuals with asymptomatic liver cirrhosis.

Antiretroviral-Associated Portal Hypertension: A New Clinical Condition? Prevalence, Predictors and Outcome

Background

Cases of severe unexplained liver disease in HIV-infected individuals have recently been reported and are often associated with exposure to didanosine (ddI) and nodular regenerative hyperplasia. Herein, we examine the clinical outcome following ddI removal.

Methods

From 3,300 HIV-infected patients attending three clinics since 2004, all who exhibited persistently elevated aminotransferases and/or significant liver fibrosis in the absence of any known cause of liver damage were identified.

Results

Thirty-two individuals (prevalence ∼1%) met the inclusion criteria - all were on antiretroviral therapy. Of these, 84% were male and 68% had acquired HIV through homosexual contact. Liver biopsy was performed in 12, of whom three showed nonspecific advanced liver fibrosis, two nodular regenerative hyperplasia and three showed only periportal fibrosis. On follow up, nine patients developed episodes of hepatic decompensation, mainly as a consequence of portal hypertension; in eight cases (25%) portal thrombosis was diagnosed. No association was found with plasma HIV RNA or CD4+ T-cell count. All patients but three had been exposed to ddI for a median of 44 months; removal of ddI in 27 was followed 12 months later by improvement in clinical and laboratory parameters in 13 (48%) patients. Finally, a trend towards liver fibrosis improvement was recognised using FibroScan®.

Conclusions

Idiopathic persistent liver enzyme elevations in HIV-infected individuals are often associated with cirrhotic and non-cirrhotic portal hypertension. Although this is a relatively rare condition, prolonged exposure to ddI seems to play a pathogenic role and removal of the drug is associated with clinical and laboratory improvements.

Darunavir: a nonpeptidic antiretroviral protease inhibitor

BACKGROUND

Protease inhibitors were a major therapeutic breakthrough in the mid-1990s for the treatment of HIV infection, which resulted in improved life expectancy for patients who had failed previous therapies. With time and evolution of the virus, however, there is a new population of patients with treatment-resistant disease and few treatment options. Darunavir is a synthetic nonpeptidic analogue of amprenavir with enhanced activity against resistant virus that became available in 2006.

OBJECTIVES

The purpose of this review was to describe the clinical pharmacology, pharmacokinetic and pharmacodynamic properties, and clinical efficacy of darunavir. Also discussed are the published clinical experience with darunavir, its adverse events, drug interactions, pharmacoeconomics, and dosing and administration.

METHODS

A MEDLINE and EMBASE search (English-language only) was performed from January 1996 through April 2007 using the key words darunavir and TMC114. Abstracts from relevant scientific meetings were searched for the years 2000 through 2007. Additionally, the US Food and Drug Administration Web site was accessed to review the new drug application summary and data presented therein.

RESULTS

Darunavir was found to maintain antiretroviral activity against HIV with protease inhibitor mutations in 6 studies. Clinical efficacy and safety data are limited to 4 controlled and 2 uncontrolled trials. In 2 large Phase IIb clinical studies, viral suppression at 48 weeks to undetectable levels in heavily pretreated patients was achieved in 45% of patients compared with 10% of patients in the control group (P < 0.001). The addition of enfuvirtide enhanced this response rate to 58% compared with 11% of the patients who did not receive enfuvirtide (P < 0.001). Gastrointestinal symptoms, nausea, and headache were the most commonly reported events.

CONCLUSIONS

Darunavir has improved activity against resistant HIV isolates in patients with few treatment choices, particularly when enfuvirtide is added. The safety profile of darunavir is comparable to other protease inhibitors based on early data.

Is it safe to switch between efavirenz and nevirapine in the event of toxicity?

The non-nucleoside reverse transcriptase inhibitors (NNRTIs) efavirenz and nevirapine are chemically distinct, but both may cause cutaneous hypersensitivity and hepatotoxicity. We reviewed the literature to assess the evidence for cross-reactivity between nevirapine and efavirenz. All papers, abstracts, or presentations, regardless of study design, that made reference to the response of patients who were switched from one NNRTI to another as a result of an adverse drug reaction were included. Most of the studies were retrospective. Recurrent reactions occurred in 30 (12.6%) of 239 reported patients with rash who were switched from nevirapine to efavirenz, compared with eight (50%) of 16 patients switched from efavirenz to nevirapine. Hepatitis did not recur in either the 11 reported patients switched from nevirapine to efavirenz, or in the single reported patient who was switched from efavirenz to nevirapine. Substituting efavirenz for nevirapine following hepatotoxicity or cutaneous hypersensitivity appears to be reasonable, providing that the adverse reaction to nevirapine was not life-threatening. There is insufficient evidence to recommend substituting nevirapine for efavirenz following either hepatotoxicity or cutaneous hypersensitivity.

Strategies to reduce late-stage drug attrition due to mitochondrial toxicity

Mitochondrial dysfunction is increasingly implicated in the etiology of drug-induced toxicities and negative side-effect profiles. Early identification of mitochondrial liabilities for new chemical entities is therefore crucial for avoiding late-stage attrition during drug development. Limitations of traditional methods for assessing mitochondrial dysfunction have discouraged routine evaluation of mitochondrial liabilities. To circumvent this bottleneck, a high-throughput screen has been developed that measures oxygen consumption; one of the most informative parameters for the assessment of mitochondrial status. This technique has revealed that some, but not all, members of many major drug classes have mitochondrial liabilities. This dichotomy encourages optimism that efficacy can be disassociated from mitochondrial toxicity, resulting in safer drugs in the future.

Inhibition of HIV replication: A powerful antiviral strategy by IFN-β gene delivery in CD4+ cells

In this study, we demonstrated the efficiency and feasibility of a gene therapy protocol against HIV infection using the antiviral effects of IFN-beta expression. Lentiviral vectors containing the human or the simian IFN-beta sequences under the influence of the murine moderate H2-kb promoter were constructed. To examine the capacity of IFN-beta to inhibit the replication of HIV in human CD4(+) cells, a transduction protocol permitting to efficiently transduce CD4(+) cells or PBMC (85+/-12% of CD4(+)-transduced cells) with a moderate expression of IFN-beta was developed. Results indicate that enforced expression of IFN-beta has no negative effects in terms of apoptosis and proliferation. In human CD4(+) cells, it drastically inhibits (up to 99.9%) replication after challenging with different strains of HIV-1. The expression of exogenous IFN-beta leads to an amplification of the CD4(+) cells (11-fold) and to a drastic decrease of the p24 protein. Micro-array analyses indicated that antiviral effect of IFN-beta could be due to a major regulation of the inflammatory response. These results are encouraging for the development of a clinical study of gene therapy against AIDS using IFN-beta.