Assessment of the patient who failed treatment for chronic hepatitis C.

Chronic hepatitis C virus (HCV) infection affects more than 4 million people in the United States and 170 million people in the world, making it a major public health problem. Currently, about one half of the patients undergoing hepatitis C treatment do not experience a sustained viral response. With time, this high nonresponse rate has created a large pool of such patients (nonresponders), many of whom have advanced fibrosis or cirrhosis.