If you haven’t begun treatment for HCV yet, this might be something called ‘
PCT’ or ‘Porphyria Cutanea Tarda. It typically manifests as blisters on the upper body, particularly in those areas that are in contact with the sun. it is also strongly associated with Hep C.
It involves iron management by the liver, and may require phlebotomy, or bloodletting, to help resolve it. Look for small blisters on sun-exposed areas; they may leave small scars as they heal over.