Lack of hepatitis C virus replication intermediate RNA in diseased skin tissue of chronic hepatitis C patients.
The extent of extrahepatic hepatitis C virus (HCV) replication seems to be low-level and confined to cells of hematopoietic lineage. However, given the spectrum of extrahepatic manifestations associated with HCV, several tissues other than the liver have been suggested as targets of HCV replication and damage. The presence and level of HCV RNA were examined in 19 skin tissue samples from patients chronically infected with HCV and referred for lichen ruber planus (n = 11) or cutaneous vasculitis associated with mixed cryoglobulinemia (n = 8). Serum HCV RNA was quantitated and genotyped by assays that are available commercially. Tissue HCV RNA of genomic- and minus-strand polarity was titrated by a strand-specific semiquantitative RT-PCR. Low titers of genomic-strand HCV RNA were found in three skin specimens from patients with cutaneous vasculitis due to mixed cryoglobulinemia, but in none with lichen ruber planus. The replication intermediate HCV RNA was not detected in any of the skin tissues examined, independent of the serum HCV RNA level or genotype. It is concluded that the occurrence of cutaneous vasculitis and lichen ruber planus in chronic hepatitis C patients is unlikely to be due to HCV replication in the skin.