Deciphering the Mechanisms Involved in Microbial Translocation Across the Spectrum of HCV Associated Liver Fibrosis

Background: \- Hepatitis C infection (HCV) is a leading cause of liver disease. Normal bacteria from the intestines may spread to the liver and blood during liver disease. This is called bacterial translocation (BT). Researchers think BT may cause liver disease to worsen. Objectives: \- To study the mechanisms involved in BT in early and advanced liver disease. To find out whether BT causes liver disease to worsen. Eligibility: \- People over age 18 with HCV and clinically stable liver disease. Design: * Participants will be screened with medical history and physical exam. They will have blood tests and imaging studies. * Participants will have 2 outpatient visits and a 3-day stay at the clinic. * At visit 1, participants will have urine and blood tests. They will have a magnetic resonance imaging (MRI) scan. A solution will be injected into a vein. The MRI scanner is a metal cylinder surrounded by a magnetic field. The participant will lie on a table that slides in and out of the cylinder. * At visit 2, a substance will be injected into a vein and swallowed. Participants will then have blood drawn 5 times over 90 minutes. * During the inpatient stay, serial blood tests will be drawn. * Participants will give 2 stool samples and have another MRI. * A needle will be inserted through the chest wall into a vein inside the liver, guided by ultrasound. The blood pressure inside this vein will be measured and blood will be drawn from it. About 1 inch of liver tissue will be removed. * A study investigator will call participants to discuss all test results.

* INCLUSION CRITERIA: 1. All age greater than 18 male or female 2. Capacity to provide written informed consent 3. Evidence of HCV RNA in 2 serum samples at least 6 months apart. 4. All HCV genotypes 5. Liver biopsy in the last 2 years prior to enrollment showing Ishak fibrosis score of either 0-1 or 5-6. An alternative to liver biopsy will be a Fibroscan study performed in the 6 months prior to study enrollment showing a score of either kPa \