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28 result(s) for "Seeff, Leonard"
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Scientific and Regulatory Perspectives in Herbal and Dietary Supplement Associated Hepatotoxicity in the United States
In the United States (US), the risk of hepatotoxicity linked to the widespread use of certain herbal products has gained increased attention among regulatory scientists. Based on current US law, all dietary supplements sold domestically, including botanical supplements, are regulated by the Food and Drug Administration (FDA) as a special category of foods. Under this designation, regulatory scientists do not routinely evaluate the efficacy of these products prior to their marketing, despite the content variability and phytochemical complexity that often characterizes them. Nonetheless, there has been notable progress in the development of advanced scientific methods to qualitatively and quantitatively measure ingredients and screen for contaminants and adulterants in botanical products when hepatotoxicity is recognized.
Peginterferon and Ribavirin for Chronic Hepatitis C
A 44-year-old woman with chronic hepatitis C has intermittent fatigue and persistent elevations in serum alanine aminotransferase levels. Treatment with peginterferon and ribavirin is recommended. Combination therapy with these two agents can lead to sustained viral control and improvement in histologic features of the liver. Side effects of therapy and treatment failures are common. Combination therapy with peginterferon and ribavirin can lead to sustained viral control and improvement in histologic features of the liver. Side effects of therapy and treatment failures are common. Foreword This Journal feature begins with a case vignette that includes a therapeutic recommendation. A discussion of the clinical problem and the mechanism of benefit of this form of therapy follows. Major clinical studies, the clinical use of this therapy, and potential adverse effects are reviewed. Relevant formal guidelines, if they exist, are presented. The article ends with the authors' clinical recommendations. A 44-year-old woman with chronic hepatitis C has intermittent fatigue and persistent elevations in serum alanine aminotransferase levels. She has had hepatitis C for 10 years. The diagnosis was made after she attempted to donate blood and was found to have antibodies against the hepatitis C virus (HCV). On questioning, she reports having used illicit injection drugs in her early 20s. The physical examination is normal except for obesity. The results of laboratory tests show an alanine aminotransferase level of 86 U per liter (normal value, <42); the alkaline phosphatase level, direct and total bilirubin levels, albumin level, prothrombin time, and complete blood count are normal. The serum HCV RNA level is 3.5 million IU per milliliter (genotype 1), and a liver biopsy specimen shows bridging fibrosis. The patient is evaluated by a hepatologist, who recommends treatment with pegylated interferon and ribavirin. The Clinical Problem Chronic hepatitis C is the major cause of chronic liver disease, cirrhosis, and liver cancer in most of the Western world, 1 and it affects approximately 3.2 million Americans. 2 The most common forms of HCV transmission, in descending order of frequency, are injection drug use, blood transfusion (before the advent of screening for the virus in the blood supply), and sexual exposure. After the discovery of HCV in 1989 and the availability of tests for antibodies against the virus in 1992, the rate of new cases of hepatitis C fell by more than 80%. 3 Although acute cases are . . .
Causality Assessment for Suspected DILI During Clinical Phases of Drug Development
Causality assessment is a critical step in establishing the diagnosis of drug induced liver injury (DILI) during drug development. DILI may resemble almost any type of liver disease, and often presents a serious challenge to clinical investigators and drug makers. The diagnosis of DILI is largely based upon a combination of a compatible clinical course, exclusion of all other reasonable causes, resemblance of clinical and pathological features to known features of liver injury due to the drug (i.e., “drug’s signature”), and incidence of liver injury among patients treated with the drug compared to placebo or comparator. Causality assessment for suspected DILI is currently performed using either evaluation by physicians with expertise in liver disorders (i.e., expert opinion) or standardized scoring instruments such as the Roussel Uclaf Causality Assessment Method (RUCAM). Both approaches are widely used in the post marketing setting. Causality assessment based on expert opinion is considered superior to standardized instruments such as RUCAM, in the setting of drug development, and is currently the preferred approach during clinical trials. There is a need for a systematic revision of RUCAM that will render it more suitable for the setting of clinical trials and drug development. Careful monitoring and meticulous data collection during clinical trials are essential in all cases with established liver injury to allow for a proper causality assessment. A workshop was convened to discuss best practices for the assessment of drug-induced liver injury (DILI) in clinical trials. This publication is based on the conclusions of this workshop.
Frequency of Elevated Hepatocellular Carcinoma (HCC) Biomarkers in Patients With Advanced Hepatitis C
Prospective studies of serum hepatocellular carcinoma (HCC) biomarkers in patients with advanced hepatitis C are lacking. The aim of this study was to determine the frequencies and performance of elevated α-fetoprotein (AFP), AFP-L3, and des-γ-carboxy prothrombin (DCP) levels as HCC biomarkers in advanced hepatitis C. Patients in the HALT-C Trial were tested every 3 months for 42 months. Screening ultrasound was performed every 12 months. Levels of biomarkers were compared in patients in whom HCC did or did not develop. In all, 855 patients were evaluated; HCC developed in 46. Among patients without HCC, 73.2% had AFP consistently <20, 24.5% had at least one AFP between 20 and 199, and 2.3% had at least one AFP value ≥200 ng/ml; 73.7% had DCP consistently <90, 11.6% had at least one DCP between 90 and 149, and 14.7% had at least one DCP value ≥150 mAU/ml. AFP-L3 ≥10% was present at least once in 9.0% and in 17.1% of those with AFP ≥20 ng/ml. Among all patients with elevated biomarkers, a diagnosis of HCC was made in 0-31.6% (depending on the biomarker and cutoff) during the subsequent 24 months. AFP ≥200 ng/ml had the highest specificity (99%), but sensitivity was ≤20%. DCP ≥40 mAU/ml had the highest sensitivity (76%), but specificity was ≤58%. Independent predictors of elevated AFP were gender (female), race (Black), more advanced disease, and HCC. Elevated DCP was associated with more advanced disease and HCC. Mild-moderate elevations in total AFP and DCP but not in AFP-L3 occur frequently in patients with chronic hepatitis C and advanced fibrosis, are related to factors other than HCC, and are poor predictors of HCC.
Hepatotoxicity Due to Hydroxycut: A Case Series
Muscletech Hydroxycut (Iovate Health Sciences Research, Oakville, Ontario, Canada) was a popular weight-loss supplement that was recalled by the manufacturer in May 2009 on the basis of reports of hepatotoxicity associated with this supplement. We sought to characterize the clinical presentation of Hydroxycut-associated liver injury and to adjudicate these cases for causal association with Hydroxycut. We assessed the causality and grading of severity of liver injury using methodology developed by the Drug-Induced Liver Injury Network (DILIN) study. Eight patients who developed liver injury after taking Hydroxycut treated at different medical centers were identified. All were hospitalized, and three of eight patients required liver transplantation. Nine other cases with adequate clinical information were obtained from the FDA MedWatch database, including one fatal case of acute liver failure. Usual symptoms were jaundice, fatigue, nausea, vomiting, and abdominal pain. Most patients exhibited a hepatocellular pattern of injury. Adjudication for causality revealed eight cases as definite, five highly likely, two probable, and two were considered to be possible. Hydroxycut has been clearly implicated as a cause for severe liver injury that may lead to acute liver failure and death. Weight-loss supplements represent a class of dietary supplements that should be regarded as capable of causing severe hepatic toxicity when the usual causes of identified liver injury cannot be otherwise elucidated.
The Contents of Herbal and Dietary Supplements Implicated in Liver Injury in the United States Are Frequently Mislabeled
The U.S. Drug Induced Liver Injury Network assayed the contents of herbal and dietary supplements collected from patients enrolled into its prospective study. The aim was to determine the accuracy of product labels, and to identify known hepatotoxins. Using high‐performance liquid chromatography coupled with mass spectrometry to assay 272 product, 51% were found to be mislabeled; that is, to have chemical contents that did not match the label. Appearance enhancement, sexual performance, and weight loss products were most commonly mislabeled. Whether the mislabeling contributed to liver injury is under study; however, the high mislabeling rate underscores the need for more stringent regulation of supplements. Herbal and dietary supplements can cause liver injury. The precise cause for injury due to supplements is difficult to determine, as this studies shows that labels are largely unreliable.
Hepatitis C Virus Infection as an Opportunistic Disease in Persons Infected with Human Immunodeficiency Virus
Hepatitis C virus (HCV) is an RNA virus of the Flaviviridae family and is a major cause of chronic hepatitis, cirrhosis, and hepatocellular carcinoma. Owing to shared routes of transmission, HCV and human immunodeficiency virus (HIV) coinfection are common, affecting approximately one-third of all HIV-infected persons in the United States. In addition, HIV coinfection is associated with higher HCV RNA level and a more rapid progression of HCV-related liver disease, which leads to an increased risk of cirrhosis. HCV infection may also impact the course and management of HIV disease, particularly by increasing the risk of antiretroviral drug-induced hepatotoxicity. Thus, chronic HCV infection acts as an opportunistic disease in HIV-infected persons, because the incidence of infection is increased and the natural history of HCV infection is accelerated in coinfected persons. Strategies to prevent primary HCV infection and to modify the progression of HCV-related liver disease are urgently needed for HIV-HCV-coinfected individuals.
Evolutionary analysis of hepatitis C virus gene sequences from 1953
Reconstructing the transmission history of infectious diseases in the absence of medical or epidemiological records often relies on the evolutionary analysis of pathogen genetic sequences. The precision of evolutionary estimates of epidemic history can be increased by the inclusion of sequences derived from ‘archived’ samples that are genetically distinct from contemporary strains. Historical sequences are especially valuable for viral pathogens that circulated for many years before being formally identified, including HIV and the hepatitis C virus (HCV). However, surprisingly few HCV isolates sampled before discovery of the virus in 1989 are currently available. Here, we report and analyse two HCV subgenomic sequences obtained from infected individuals in 1953, which represent the oldest genetic evidence of HCV infection. The pairwise genetic diversity between the two sequences indicates a substantial period of HCV transmission prior to the 1950s, and their inclusion in evolutionary analyses provides new estimates of the common ancestor of HCV in the USA. To explore and validate the evolutionary information provided by these sequences, we used a new phylogenetic molecular clock method to estimate the date of sampling of the archived strains, plus the dates of four more contemporary reference genomes. Despite the short fragments available, we conclude that the archived sequences are consistent with a proposed sampling date of 1953, although statistical uncertainty is large. Our cross-validation analyses suggest that the bias and low statistical power observed here likely arise from a combination of high evolutionary rate heterogeneity and an unstructured, star-like phylogeny. We expect that attempts to date other historical viruses under similar circumstances will meet similar problems.
Testing for Hepatitis C Virus Infection Should Be Routine for Persons at Increased Risk for Infection
In the United States, chronic hepatitis C virus (HCV) infection affects an estimated 3 million persons, most younger than 50 years of age. It is one of the leading causes of chronic liver disease morbidity and mortality and the most common indication for liver transplantation. Effective treatment can eradicate the virus and eliminate or reduce liver inflammation and fibrosis, and counseling and immunization can modify or prevent the adverse effect of cofactors (for example, alcohol consumption or co-infections) on disease progression. However, controversy surrounds the need to routinely identify asymptomatic HCV-infected persons. Because no data currently demonstrate that treatment or other interventions will reduce future cases of HCV-related chronic disease and deaths, the U.S. Preventive Services Task Force found insufficient evidence to recommend for or against routine screening for HCV infection in adults at high risk. Chronic hepatitis C would require many years of follow-up to determine the incidence of complication after treatment of or other interventions in asymptomatic persons. It seems inappropriate to wait several decades to measure the impact of early identification of this viral infection when current data support a positive therapeutic effect that points to long-term benefits. In addition, treatment and other interventions must be provided before cirrhosis or liver failure occurs. Therefore, medical and public health professionals should continue the practice of screening persons for risk factors; offering testing to those at increased risk for HCV infection; and providing infected persons with appropriate counseling, medical evaluation, and treatment.
Use of complementary and alternative medicine in patients with liver disease
OBJECTIVES: Complementary and alternative medicine (CAM) is used by 42% of the U.S. population. Its use among patients with chronic liver disease has not been well defined. Toward that end, we surveyed patients in six geographically diverse liver disease clinics in the United States for use of CAM. METHODS: Patients attending six liver disease clinics were polled via a common questionnaire regarding their use of CAM. Demographic information was obtained to identify predictors of CAM use. Statistical analysis included univariate and multivariate analysis using logistic regression. RESULTS: A total of 989 patients completed the questionnaire. Of these, 389 (39%) admitted to using some form of CAM at least once during the preceding month; 21% admitted to using herbal preparations, and 13% used herbs to treat their liver disease. Five variables were found to be predictive of alternative therapy use: female sex, young age, level of education, annual income, and geographic location. In all, 74% of patients reported using CAM in addition to the medications prescribed by their physician, but 26% did not inform their physician of their CAM use. CONCLUSIONS: CAM use is as common among patients visiting liver disease clinics in the United States as in the general population (39% vs 42%). Many patients are using herbs to treat their liver disease but are declining to discuss this use with their physician.