View clinical trials related to Hepatitis A.
Filter by:This protocol represents a continuation of a series of prospective studies to define the incidence and etiology of transfusion-associated hepatitis (TAH) and to examine the impact on TAH of various modifications in the selection of blood donors. The primary goal of the study will be to determine TAH incidence after the institution of a variety of interventive measures to exclude hepatitis and AIDS virus carriers: including surrogate assays (ALT, anti-HBc), a specific assay for the hepatitis C virus (HCV), a specific assay for the human immunodeficiency virus (HIV) and intensified donor questioning for high-risk behavior patterns. There is high probability that the exclusion of donors at high risk for AIDS transmission will also exclude donors at high risk for hepatitis transmission. Incidence data obtained in the study will be enhanced by the simultaneous follow-up of a control population undergoing identical surgical procedures, but receiving no blood or only autologous blood. This control population, made possible by the recent dramatic increase in the amount of autologous blood utilized, will allow for a clear distinction between transfusion-associated hepatitis and that due to nosocomial transmission or other background causes of hepatocellular inflammation in cardiac surgery patients.
OBJECTIVES: I. Determine whether the initial response to interferon alfa (IFN-A) can be increased by starting at a dose of 5 MU three times a week in patients with chronic hepatitis C. II. Determine whether patients who had normalized alanine aminotransferase (ALT) levels can maintain normal ALT during stepwise dose reduction from 5 MU to 3 MU to 1.5 MU.
Hepatitis C is a disease of the liver caused by the Hepatitis C Virus (HCV). Patients with hepatitis C may feel well and show no signs or symptoms of being ill. However, researchers would like to study the long-term effects of this disease. Volunteer blood donors diagnosed with chronic hepatitis C viral (HCV) and various levels of liver enzyme activity will be offered a complete medical evaluation and liver biopsy. The tests will enable researchers to provide the patients with an idea of how severe their liver disease is. The virus and patient will be studied in order to understand why patients with hepatitis C develop different levels of liver damage.
The proposed study aims to evaluate, investigate, and follow-up patients suffering from acute and chronic liver disease. The study will focus on understanding diseases affecting the liver. Patients participating in the study will first undergo a routine check-up as an outpatient. They will be asked to provide blood and urine samples for laboratory testing and will undergo an ultrasound of the liver. Ultrasound examinations use sound waves to determine the size and texture of the liver. After the initial visit subjects will be requested to follow-up once a year at the outpatient department for a similar check-up. Additional tests may be requested throughout the study to provide information for other research studies and individual consent will be requested. These tests may include liver biopsies, skin biopsies, and / or specialized blood, plasma, and lymphocyte examinations. Subjects that qualify for medications presently being studied may be offered the opportunity to benefit from experimental therapy.
Hepatitis is an inflammation of the liver. Hepatitis can be caused by an infection with a virus, but poisonous (toxic) substances can also cause it. Researchers have identified several of the viruses responsible for hepatitis, however some patients with hepatitis show no evidence of being infected with known hepatitis viruses. Researchers call conditions like this, seronegative hepatitis. It means that a patient has hepatitis but he/she does not have evidence in their blood of a viral infection. Seronegative hepatitis is often complicated by autoimmune disorders and associated severe disorders especially, fulminant hepatitis of childhood and post-hepatitis aplastic anemia. Researchers have attempted to identify the cause of these conditions but have been unsuccessful. Therefore, this study was developed to collect blood and stool samples from patients with seronegative hepatitis in order to help identify the virus responsible.
Chronic hepatitis C is a disease of the liver caused by the hepatitis C virus. The disease can be serious and even fatal. Approximately 25% of patients with chronic hepatitis C will develop cirrhosis and some of these patients will develop cancer of the liver or liver failure. Presently the disease is treated with a combination of alpha interferon or peginterferon (antiviral and immune stimulating drugs) and ribavirin (an antiviral drug). Alpha interferon is given by injection three times a week whereas peginterferon is given by injection only once a week. Ribavirin is given as a tablet by mouth twice a day. The combination therapy is given for 6 to months. About half of the patients given these medications will receive a lasting benefit and many patients do not respond well to the combination therapy. This study will select up to 50 patients will chronic hepatitis C who have not responded to combination therapy or who could not stand the side effects associated with interferon or peginterferon therapy. These subjects will be evaluated and undergo liver biopsy to determine their present liver condition. If selected as subjects they will be started on single drug therapy with ribavirin. The drug will be given orally twice a day at a dose based on the patient's body weight. The patients will be followed on an out-patient basis. They will we asked to return for regular check-ups and blood tests every 2 to 8 weeks for the duration of the study. After 6 months, the medication will be stopped or adjusted based on the results of the subject's blood tests (liver enzymes). A response is considered if a decrease of 50% or more of the initial liver enzyme (alanine aminotransferase, ALT) is noted. A complete response will be considered if liver enzymes return to normal levels. Therapy will be discontinued after 6 months if patients do not respond. However, patients that respond to the single drug therapy will continue to receive the medication at a decreased dose. The patients will remain on an appropriate dose for up to 8 years with repeat liver biopsies at 2, 4 and 8 years to assess progress. This study will determine if long-term therapy with ribavirin is safe and effective.
Hepatitis C is a major cause of liver disease in the United States and leads to cirrhosis of the liver in approximately one-third of patients some of whom will ultimately suffer from liver failure or liver cancer. At present, the recommended therapy of hepatitis C is the combination of alpha interferon and ribavirin given for 6 to 12 months. Ribavirin is a antiviral drug that is given by mouth. Interferon is both an antiviral and an immune medication which must be given by injections (three times a week) and has many difficult side effects. The purpose of this study is to determine whether the combination of ribavirin and interferon improve the liver disease of hepatitis C and whether improvements can be maintained by continuing ribavirin therapy long-term. This study will take 100 to 120 patients suffering from hepatitis C and place them under combination drug therapy with alpha interferon and ribavirin. The course of drug therapy is scheduled to last 6 to 12 months. Patients will be selected after appropriate screening for hepatitis C virus and elevated liver enzymes are conducted and liver biopsy shows chronic hepatitis with some degree of injury and scarring. During the first 6 months of the study, subjects will be asked to return to the outpatient clinic for routine check-ups and blood tests every 2 to 4 weeks. Blood tests will include tests for hepatitis C virus. If the virus test becomes negative on treatment, the therapy will be considered successful and will be continued for a full 6 or 12 months (depending upon the strain of virus). If the virus test does not become negative during the first six months of treatment, subjects will be considered "non-responders" and will stop taking interferon but will continue on ribavirin alone or an identically appearing placebo tablet. These non-responsive subjects will continue this therapy for an additional 12 months. (A year-and-a-half total). Upon completion of the drug therapies, subjects will be requested to submit blood samples and undergo a liver biopsy to determine if the therapy was successful. Test results that reveal a loss of hepatitis C antibodies or normal levels of liver enzymes will be deemed successful. Patients that have successful laboratory test results will be considered for continuation of ribavirin therapy. Patients that received placebo for a year will be eligible to receive ribavirin long-term at the end of the study.
Following guidelines issued by the Centers for Disease Control, the Clinical Center implemented a Universal Precautions policy in November 1987 in an attempt to reduce healthcare workers' risks for occupational exposures to bloodborne pathogens. All hospital personnel whose jobs entailed potential exposure to patients' blood and body substances were required to attend a training session and complete a written examination. Based on data from surveys conducted before and twelve months after training in Universal Precautions, the frequency of cutaneous exposure to blood decreased by 50% in temporal association with implementation of Universal Precautions. Staff at the Clinical Center are required to take a refresher course in Universal Precautions annually. The prevalence of bloodborne infections is high in Japan; however, Universal Precautions are not widely practiced in Japan. This study is designed: 1) to evaluate and compare nurses' knowledge of the epidemiology, pathogenesis, occupational risks, and appropriate prevention strategies for managing patients infected with bloodborne pathogens in the healthcare setting in seven university hospitals in Japan and at the Clinical Center of the National Institutes of Health in the US; 2) to compare self-reported levels of compliance with existing infection control recommendations designed to limit risk for exposure to bloodborne pathogens in all four institutions; 3) to compare self-reported frequencies of cutaneous exposures to blood at the four hospitals in the study; and 4) to evaluate the effect of educational intervention on nurses perceived compliance with recommendations and on the frequency of self-reported exposures to blood.
Chronic hepatitis B is a disease of the liver caused by the hepatitis B virus. It affects nearly 1 million Americans. Approximately 25% of patients with chronic hepatitis B will develop liver cirrhosis and 5% of patients will develop liver cancer. Presently, two medications have been shown effective in the treatment of hepatitis B: lamivudine and alpha interferon. Alpha interferon (an antiviral drug that acts through the immune system) is given by injection once daily or three times a week for four to six months. Lamivudine (also known as 3-thiacytidine: 3TC) is an antiviral medication given as a pill once a day for twelve months. These treatments have been known to provide long-term improvement in one third of patients receiving them. In previous research, the drug lamivudine was shown to stop the growth of the hepatitis B virus and to lead marked decreases in the levels of hepatitis B virus and to improvements in the disease in 50 to 70% of patients. However, once lamivudine therapy was discontinued the virus returned to levels noted before the therapy began. In those studies lamivudine was given for 3 to 12 months then discontinued. This study will investigate the safety and effectiveness of long-term therapy with lamivudine. This study will select 60 patients diagnosed with hepatitis B. After a thorough medical examination and liver biopsy, subjects will be given lamivudine. The drug will be taken by mouth in tablet form (100 mg) once a day for up to 5 years. Subjects will undergo regular check-ups and after 1 year of therapy be admitted to the Clinical Center for another medical examination and liver biopsy to assess progress. Patients who have benefitted from the therapy will continue taking the medication for up to 5 years. A third liver biopsy will be done during the last year of treatment. The effectiveness of lamivudine will be determined by whether levels of hepatitis B virus decrease in the blood, whether liver enzymes improve, and whether inflammation and scarring decreases in the liver biopsies.
This study evaluates patients infected with both HIV and Hepatitis C virus (HCV) who are receiving anti-HIV drugs. The purpose of this study is to learn more about HCV infection in patients whose HIV blood level decreases to less than 500 copies/ml.