Mitochondrial toxicity associated with HAART following liver transplantation in an HIV-infected recipient

Nucleoside reverse transcriptase inhibitors induced hepatocellular mitochondrial DNA lesions and compensatory enhancement of mitochondrial function and DNA repair

Nucleoside reverse transcriptase inhibitors (NRTIs) are the backbone of combined antiretroviral therapy (cART) and are widely used in anti-human immunodeficiency virus (HIV) therapy. Long-term administration of NRTIs can result in mitochondrial dysfunction in certain HIV-1-infected patients. However, NRTI-associated liver mitochondrial toxicity is not well known. Herein, the liver autopsy of acquired immune deficiency syndrome (AIDS) patients and the liver tissues of mice with 12 months of NRTI exposure were used to identify NRTI-associated liver toxicity with immunofluorescence, quantitative real-time polymerase chain reaction (qPCR), Amplex red and horseradish peroxidase, and cloning and sequencing. Laser capture microdissection was used to capture hepatocytes from liver tissues. We observed DNA oxidative damage and mitochondrial DNA (mtDNA) loss in the livers of AIDS patients, and cART patients had higher DNA oxidative damage and lower DNA repair function in liver tissues than non-cART patients. We also observed liver oxidative damage, increased DNA repair and mtDNA loss in mice with exposure to four different NRTIs for 12 months, and hepatocytes had no more mtDNA loss than liver tissues. Although NRTIs could induce mitochondrial hydrogen peroxide production, increased mitochondrial oxygen consumption was found with a Clark-type electrode. The captured hepatocytes had greater diversity in their mtDNA D-loop, dehydrogenase subunit1 (ND1) and ND4 than the controls. Long-term NRTI exposure induced single nucleotide variation in hepatocellular mtDNA D-loop, ND1 and ND4. Our findings indicate that NRTIs can induce liver mtDNA lesions, but simultaneously enhance mitochondrial function and mtDNA repair.

Successful Treatment of Mitochondrial Toxicity in an HIV-Positive Patient After Liver Transplantation

Liver transplantation in patients infected with the human immunodeficiency virus (HIV) has been increasingly performed with reasonable outcomes; however, medical management of both immunosuppression and antiretroviral therapy can be challenging owing to drug toxicities and interactions. Nucleoside reverse transcriptase inhibitors (NRTIs), a common backbone of highly active antiretroviral therapy (HAART), were the first class of effective antiretroviral drugs developed. NRTIs are commonly used for posttransplant HAART therapy and have a rare but fatal complication of mitochondrial toxicity, manifesting as severe lactic acidosis, hepatic steatosis, and lipoatrophy. Herein, we have reported on the first known successful treatment of severe mitochondrial toxicity secondary to NRTIs in an HIV-infected transplant recipient.

Drug-drug interactions between antiretroviral and immunosuppressive agents in HIV-infected patients after solid organ transplantation: a review

Since the introduction of combination antiretroviral therapy (cART) resulting in the prolonged survival of HIV-infected patients, HIV infection is no longer considered to be a contraindication for solid organ transplantation (SOT). The combined management of antiretroviral and immunosuppressive therapy proved to be extremely challenging, as witnessed by high rates of allograft rejection and drug toxicity, but the profound drug-drug interactions between immunosuppressants and cART, especially protease inhibitors (PIs) also play an important role. Caution and frequent drug level monitoring of calcineurin inhibitors, such as tacrolimus are necessary when PIs are (re)introduced or withdrawn in HIV-infected recipients. Furthermore, the pharmacokinetics of glucocorticoids and mTOR inhibitors are seriously affected by PIs. With the introduction of integrase inhibitors, CCR5-antagonists and fusion inhibitors which cause significantly less pharmacokinetic interactions, have minor overlapping toxicity, and offer the advantage of pharmacodynamic synergy, it is time to revaluate what may be considered the optimal antiretroviral regimen in SOT recipients. In this review we provide a brief overview of the recent success of SOT in the HIV population, and an update on the pharmacokinetic and pharmacodynamic interactions between currently available cART and immunosuppressants in HIV-infected patients, who underwent SOT.

Liver transplantation for patients with human immunodeficiency virus and hepatitis C virus coinfection with special reference to hemophiliac recipients in Japan

Liver transplantation for patients with hepatitis C virus (HCV) and human immunodeficiency virus (HIV) remains challenging. The advent of highly active antiretroviral therapy (HAART) for HIV has reduced mortality from opportunistic infection related to acquired immunodeficiency syndrome dramatically, while about 50% of patients die of end-stage liver cirrhosis resulting from HCV. In Japan, liver cirrhosis frequently develops after HCV-HIV coinfection resulting from previously transfused infected blood products for hemophilia. The problems of liver transplantation for those patients arise from the need to control calcineurin inhibitor with HAART drugs, the difficulty of using interferon after liver transplantation with HAART, and the need to control intraoperative coagulopathy associated with hemophilia. We review published reports of liver transplantation for these patients in the updated world literature.

Liver transplant outcomes in HIV-infected patients: a systematic review and meta-analysis with synthetic cohort

OBJECTIVES

The relative success of liver transplantation in those with HIV compared to HIV-uninfected individuals remains a point of intense debate. We aimed to evaluate the effectiveness of liver transplantation in HIV-hepatitis co-infected patients using a meta-analysis and individual patient data meta-analysis as a synthetic cohort.

METHODS

We searched MEDLINE via PubMed, EMBASE, Cochrane CENTRAL, AIDSLINE (inception to 2010), AMED, CINAHL, TOXNET, Development and Reproductive Toxicology, Hazardous Substances Databank, Psych-info and relevant conferences. We included cohort studies and individual case-reports evaluating survival of co-infected transplant patients. We abstracted data on cohort and case demographics and outcomes. We pooled cohorts using a random-effects analysis and created a synthetic cohort of cases using individual patient data. We confirmed this with the pooled cohort analysis.

RESULTS

We included 15 cohort studies and 49 case series with individual patient data. At 12 months, 84.4% [95% confidence interval (CI) 81.1-87.8%] of patients had survived. Within the HIV-infected population evaluated, HIV-hepatitis B virus (HBV) co-infection was associated with optimal survival. In an adjusted model, individuals positive for HBV were 8.28 (95% CI 2.26-30.33) times more likely to survive when compared to those without HBV. Further, individuals with an undetectable HIV viral load at the time of transplantation were 2.89 (95% CI 1.41-5.91) times more likely to survive when compared to those with detectable HIV viremia. Hepatitis C virus was not a predictor of patient survival when adjusted for by other key predictors [0.54 (95% CI 0.17-1.80)].

Liver transplantation in HCV/HIV positive patients

Since the introduction of highly active antiretroviral therapy (HAART) in 1996 for human immunodeficiency virus (HIV)-infected patients, the incidence of liver diseases secondary to co-infection with hepatitis C has increased. Although data on the outcome of liver transplantation in HIV-infected recipients is limited, the overall results to date seem to be comparable to that in non-HIV-infected recipients. Liver transplant centers are now accepting HIV-infected individuals as organ recipients. Post-transplantation HIV replication is controlled by HAART. Hepatitis C re-infection of the liver graft, however, remains an important problem because cirrhotic changes of the liver graft may be more rapid in HIV-infected recipients. Interactions between the HAART components and immunosuppressive drugs influence drug metabolism and therefore meticulous monitoring of drug blood level concentrations is required. The risk of opportunistic infection in HIV-positive transplant patients seems to be similar to that in HIV-negative transplant recipients.

Liver transplant in patients with HIV: infection risk associated with HIV and post-transplant immunosuppression

Before the introduction of highly active antiretroviral therapy, HIV-infected patients who underwent liver transplantation (LT) had poor survival, mainly because of a rapid progression to AIDS and its infectious complications during the post-LT immunosuppression phase. However, in the era of highly active antiretroviral therapy, under some specific and well-determined conditions, LT might be as safe and efficacious in HIV patients as it is in non-HIV-infected patients. End-stage liver failure as caused by hepatitis B virus, cirrhosis, and hepatotoxicity should be considered indications for LT in every transplant center. Because of the almost universal hepatitis C virus reinfection and its accelerated course post-LT, LT in hepatitis C virus-coinfected patients deserves more caution and more extended follow-up before it is accepted as a standard indication for LT in HIV-infected patients.

Liver transplantation in HIV-positive patients

This article reviews the worldwide evolution of liver transplantation as a therapeutic intervention in HIV-infected patients. Since the introduction of highly active antiretroviral therapy (HAART), liver disease secondary to viral hepatitis has become a leading cause of morbidity and mortality among HIV-positive individuals. The authors contrast survival data from pilot studies in the pre-HAART era to those data emerging from more recent trials. Particular emphasis is placed on current selection criteria for HIV-positive transplant candidates. Additional consideration is given to the effect of prolonged transplant waiting time on survival outcome. The complexity of the post-transplant medication regime, including drug interactions, optimal immunosuppression and most appropriate HAART regimes, are discussed in detail. Postoperative challenges including optimal management of hepatitis B virus and recurrent hepatitis C virus post-transplant are reviewed separately. The ethical and practical arguments relating to the use of a scarce and valuable resource in this population are debated. The authors conclude with several recommendations to assist pretransplant assessment and postoperative management of such complex patients and speculate on the direction and evolution of this field in the coming years.

Survival and recurrence of hepatitis C after liver transplantation in patients coinfected with human immunodeficiency virus and hepatitis C virus

Liver transplantation in patients coinfected with human immunodeficiency virus (HIV) and hepatitis C virus (HCV) is a recent indication. In a single center, we have compared the survival and severity of recurrent HCV infection after liver transplantation in HIV-HCV-coinfected and HCV-monoinfected patients. Seventy-nine patients receiving a first liver graft for HCV-related liver disease between 1999 and 2005 were included. Among them, 35 had highly active antiretroviral therapy-controlled HIV infection. All patients were monitored for HCV viral load and liver histology during the posttransplantation course. Coinfected patients were younger (43 +/- 6 versus 55 +/- 8 years, P < 0.0001) and had a higher Model for End-Stage Liver Disease (MELD) score (18.8 +/- 7.4 versus 14.8 +/- 4.7; P = 0.008). The 2-year and 5-year survival rates were 73% and 51% and 91% and 81% in coinfected patients and monoinfected patients, respectively (log-rank P = 0.004). Under multivariate Cox analysis, survival was related only to the MELD score (P = 0.03; risk ratio, 1.08; 95% confidence interval, 1.01, 1.15). Using the Kaplan-Meier method, the progression to fibrosis >or= F2 was significantly higher in the coinfected group (P < 0.0001).

CONCLUSION

The results of liver transplantation in HIV-HCV-coinfected patients were satisfactory in terms of survival benefit. Earlier referral of these patients to a liver transplant unit, the use of new drugs effective against HCV, and an avoidance of drug toxicity are mandatory if we are to improve the results of this challenging indication for liver transplantation.

Liver transplantation in HIV-HCV coinfected patients: a case-control study

Liver transplantation (LT) for hepatitis C virus (HCV)-associated cirrhosis in human immunodeficiency virus (HIV)-infected patients was compared with non-HIV patients. Nine patients with HIV-HCV coinfection were compared with patients transplanted before and after each HIV patient (control group). Immunosuppression consisted in tacrolimus with steroids or mycophenolate mofetil. Acute cellular rejection and three-year actuarial patient survival were respectively 44% and 87.5% in HIV group and 22% and 93.7% in the control group (P=NS). Acute hepatitis C virus occurred earlier (2.3 vs. 4.3 months) and was more cholestatic (mean bilirubin: 10.8 vs. 1.6 mg/dL) in the HIV group. Eight (100%) HIV and nine (64.3%) control patients received antiviral treatment with pegylated interferon and ribavirin. One patient (11.1%) of the control group and one patient (20%) of the HIV group presented a sustained virologic response (P=NS). Short- to midterm results of LT in HIV-HCV co-infected patients were excellent and similar to non-HIV patients.

Early Antiviral Treatment of Hepatitis C Virus Recurrence after Liver Transplantation in HIV-Infected Patients

Objective

To investigate the efficacy of early antiviral treatment for hepatitis C virus (HCV) recurrence in HIV/HCV-coinfected patients undergoing liver transplantation for end-stage liver disease.

Methods

Open prospective trial of early treatment of HCV recurrence in consecutive HIV/HCV-coinfected patients transplanted at a tertiary hospital in Barcelona between 2002 and 2004. All patients had indication for liver transplantation, no previous CDC class C HIV-associated opportunistic events, a CD4+ T-cell count >100 cells/fxl, and undetectable plasma HIV RNA on highly active antiretroviral therapy. Treatment with pegylated interferon-a2b (1.5 μg/kg/week) and ribavirin (800–1000 mg/day) was given for 24 to 48 weeks, as soon as HCV recurrence was histologically documented.

Results

Of six patients who underwent transplant, five patients surviving the early post-transplantation period developed HCV recurrence, presenting as severe cholestatic hepatitis in three, and were started on antiviral treatment a median of 12 weeks (range: 5–31) after transplantation. After a median follow-up of 24 months all treated patients were alive. Biochemical response was achieved in all patients, although only one achieved a sustained virological response. Mild rejection before HCV recurrence occurred in two cases. Treatment was well tolerated with no episodes of rejection or mitochondrial toxicity. No patient required modification of the antiretroviral regimen. Liver biopsies performed in patients without virological response, 12–34 months after transplantation, showed cirrhosis in two and moderate chronic active hepatitis in the remainder.

Conclusions

Despite early antiviral treatment, severe HCV recurrence after liver transplantation may compromise long-term survival in HIV-infected patients. Improved treatment strategies for these patients are urgently required.

Hepatobiliary pathology

PURPOSE OF REVIEW

This review highlights recent publications on hepatobiliary pathology concerning several unusual types of hepatitis, fatty liver disease, disorders of the biliary tree and other topics that have a substantial impact on liver biopsy interpretation.

RECENT FINDINGS

In the outbreak of severe acute respiratory syndrome (SARS), many patients had abnormalities in liver function tests. Liver biopsy findings in three cases were reported that showed a generic picture of hepatitis, with exceptionally increased mitotic activity. The role of portal myofibroblasts in cirrhosis was examined in several studies. A newly described lesion, isolated ductular hyperplasia (IDH) was found in patients with prolonged abnormalities of liver function tests of uncertain origin. Hyperplastic, well-differentiated bile ductules were seen on liver biopsy in the absence of any identifiable biliary disease. Hereditary hemochromatosis is now a complex entity with various clinicopathological forms based on mutations in the HFE gene and other iron-homeostatic genes such as transferrin receptor 2 and ferroportin 1. In some of these heritable forms of primary iron overload, stainable iron is present in both hepatocytes and Kupffer cells. After liver transplantation, differentiating recurrent HCV infection from acute rejection on liver biopsy is problematic, with exceptionally low inter- and intra-observer reliability shown in one study.

SUMMARY

The hepatitis associated with the SARS coronavirus, Isolated Ductular Hyperplasia in patients with liver function test abnormalities and other topics with pathologic relevance are reviewed.

Drug-induced liver disease 2004

PURPOSE OF REVIEW

To summarize the salient reviews, studies and case reports and series that dealt with clinical, pathological, methodological, and epidemiological descriptions of drug-induced liver disease in the calendar year 2004.

RECENT FINDINGS

While no new causes of drug-induced liver injury were reported for 2004, several new reports of previously recognized hepatotoxins, including herbal products, were published. These include the antiretroviral drugs for HIV and agents to manage tuberculosis. Acetaminophen (APAP) retained its preeminent position as the leading cause of drug-induced acute liver failure, currently accounting for nearly 50% of cases according to the latest figures from the U.S. Acute Liver Failure Study Group. Not surprisingly, APAP also heads the list of drugs and toxins leading to liver transplantation for acute hepatic failure. Efforts to reduce the number of cases of intentional APAP poisonings by restricting the number of tablets sold at any one time in the UK are ongoing, but the success of the program may be lessening, as was pointed out this year. The use of potentially hepatotoxic medications in patients with underlying liver disease was examined with the statins, and they emerged as a safe class for use in this setting.

SUMMARY

Given the apparent increasing incidence of acute liver failure attributable to APAP in the US, additional efforts are still needed to better define the risks associated with its use and to further reduce the incidence of severe liver injury from this widely used agent.

Hepatitis C virus viral recurrence and liver mitochondrial damage after liver transplantation in HIV-HCV co-infected patients

BACKGROUND/AIMS

As life expectancy in HIV-HCV co-infected patients improves, end stage liver disease requiring liver transplantation (LT) may become an emerging problem. We report the Paul Brousse Hospital experience of transplantation for end stage cirrhosis in HIV-HCV co-infected patients.

METHODS

Seven consecutive HIV-HCV co-infected patients were transplanted between December 1999 and December 2002 for end stage liver disease due to HCV. All patients were treated by highly active antiretroviral therapy (HAART), HIV plasma viral load was <400 copies/ml and median CD4 lymphocyte count was 306 cells/mm3 (range, 103-510) before LT. At the time of evaluation (March 2003), the median follow-up was 21 months (range, 4-40).

RESULTS

Two patients died, 4 and 22 months, respectively after LT. At the last biopsy, METAVIR score was staged F4 in two patients, F3 in two, and F1 in one. Microvesicular steatosis was noted in nearly all patients. The ratio of mitochondrial to nuclear DNA was low in three of four patients examined as compared with the amount of liver mtDNA found in eight HIV-negative, HCV-infected controls (P=0.01).

CONCLUSIONS

A significant defect in the activity of the respiratory chain complex IV was noted in all five patients studied. Mitochondrial hepatotoxicity and severe HCV recurrence occur in HIV-HCV co-infected patients after LT.

The Role of Hepatitis C Virus (HCV) in Mitochondrial Dna Damage in HIV/HCV-Coinfected Individuals

Oxidative stress accompanying hepatitis C virus (HCV) infection seems to result in mitochondrial (mt) dysfunction. In HIV/HCV-coinfected individuals, HCV-related mt damage could be further enhanced and clinical manifestations of mt damage may appear, particularly following exposure to some antiretroviral drugs. Furthermore, when HCV medications are used together with certain antiretrovirals, the risk of developing mt adverse events may be particularly frequent, such as development of pancreatitis when ribavirin and didanosine are coadministered. The management of HIV/HCV-coinfected individuals needs to consider the high risk of mitochondria-associated toxicities in this population, which may significantly influence treatment decisions and therapeutic modalities.

Liver transplantation in patients with HIV infection

1. Liver transplantation for human immunodeficiency virus (HIV)-positive patients with end-stage liver disease in the era of highly active retroviral therapy has proven to be an effective treatment. The concerns of HIV progression have not been borne out by the growing worldwide experience. 2. CD4 counts are stable and HIV viral load is controllable with medication following liver transplantation. 3. Hepatitis C virus (HCV) coinfection in HIV-positive recipients is universal, but the severity of recurrence does not appear to be different from that in HIV-negative patients with HCV liver disease. 4. Complex pharmacokinetic interactions between the calcineurin inhibitors used for immunosuppression along with protease inhibitors are present, but management directed at recognizing the need for monitoring levels does not appear to increase the risk of toxicity. 5. The degree of immunosuppression from iatrogenic drug therapy and HIV does not lead to increased risk of infectious complications.