Verrucae Planae Within Previous Xenograft Sites of Burn Wounds.

Burn injuries are known to compromise host immune defenses through disruption of mucocutaneous barriers and suppression of cell-mediated immune responses, which may render patients with burn injuries susceptible to viral infections in the days to years after an initial insult. We report a case of verrucae planae developing as a secondary condition confined to former xenograft sites in a child, appearing more than 3.5 years after initial second-degree burn injuries. Only a few reports have previously described the development of verrucae in former burn sites, with most reporting latency to onset of verrucae appearance of months rather than years. Current hypotheses suggest that the postburn immune response shifts from an early proinflammatory to a late antiinflammatory response characterized by altered cytokine profiles and diminished cellular cytotoxicity mediated by cytotoxic T-lymphocytes, natural killer cells, and epidermal antigen-presenting cells, which together likely contribute to an enduring postburn regional immunosuppression that allows for the seeding and proliferation of viral agents.