Delayed viral clearance of chronic hepatitis C in patients after treatment failure.

Hepatitis C virus (HCV) infection usually progresses to chronic hepatitis, with rare cases of spontaneous viral eradication. We present herein four cases involving patients that were initially declared to have failed to respond to treatments, based on the presence of HCV RNA that was still detectable after completion of the standard treatment for chronic hepatitis C with genotype 2. However, the HCV RNA became undetectable, with a delayed response, after discontinuation of therapy. Two of the four patients were diagnosed as treatment failures after extended treatment, and the other two received no further treatment after the standard treatment. All four patients maintained a sustained virological response during the periodic follow-up after delayed viral clearance.