- Hepatitis: known to have serologic evidence of hepatitis B infection based on the results of testing for hepatitis B surface antigen (HBsAg), or antibodies against hepatitis B core antigen (HBc) and/or hepatitis B surface antigen (HBs) as follows: a) Patients positive for HBsAg are excluded; ) Patients negative for HBsAg and anti-HBc antibody but positive for anti-HBs antibody and with no history of hepatitis B vaccination are excluded; c) Patients negative for HBsAg but positive for both anti-HBc and anti-HBs antibodies are excluded; d) Patients negative for HBsAg and anti-HBs antibody but positive for anti-HBc antibody are excluded; e) Or has known serologic evidence of hepatitis C infection based on the results of testing for hepatitis C antibody and hepatitis C recombinant immunoblot assay (RIBA) as follows: Patients with a positive test for Hepatitis C antibody confirmed on the same sample with a Hepatitis C RIBA immunoblot assay. Patients who are positive for Hepatitis C antibody, and who are negative when the Hepatitis C RIBA immunoblot assay is performed on the same sample, will be eligible to participate. Patients who are positive for Hepatitis C antibody and who have a positive or indeterminate result when the Hepatitis C RIBA immunoblot assay is performed on the same sample, will not be eligible to participate.