Lichen planus in children: a possible complication of hepatitis B vaccines.

Lichen planus (LP) has been reported as a complication of hepatitis B vaccination in both adults and children. According to published observations, an autoimmune reaction may be triggered by the viral S epitope. In children, LP is uncommon and, because of its atypical clinical presentation, definitive diagnosis may require biopsy. We investigated the possible association of recombinant hepatitis B virus (HBV) vaccines with childhood LP or LP-like eruptions seen in our hospital over the last 3 years. Only biopsy-confirmed cases in which the clinical history could be thoroughly scrutinized were included. We report five patients less than 16 years of age in whom such an association could be supported by relevant data. Thirteen similar pediatric and 15 adult cases have been reported from various countries in the last 5 years. The data indicate that LP is a complication that rarely occurs in children receiving the HBV vaccine. It appears without known predisposing factors and has variable clinical presentations while the histologic findings are consistent and, with minor variations, typical of LP.