Background: Lichen planus is a papulosquamous dermatosis which has recently been linked to infection with hepatitis C virus. It is unclear whether or not viral antigens may be present in the cutaneous lesions of lichen planus.
Materials and methods: Twenty-five paraffin-embedded samples of glabrous lichen planus were evaluated using immunoperoxidase staining for the presence of hepatitis C virions. Control tissues consisted of hepatitis C-infected hepatic tissue (n = 2), normal hepatic tissue (n = 2), normal human skin (n = 1), and two cutaneous biopsies of lichen planus from persons known to be infected with hepatitis C.
Results: The sections of hepatitis C-infected liver tissue stained positive for hepatitis C virions. The 25 biopsies of glabrous lichen planus, the two biopsies of lichen planus from hepatitis C patients, the two sections of normal liver, and the one normal skin sample all failed to take up the stain.
Conclusions: Cutaneous lesions of lichen planus are more probably reactive to the underlying infection than a manifestation of skin involvement by this disease. This theory is supported by the histologic findings in a lichenoid drug eruption, which are virtually identical to those of idiopathic lichen planus. Insufficient sensitivity by the immunoperoxidase procedure used is a possible explanation for our results; however, it appears more probable that no virus exists at the sites of cutaneous involvement.