Histopathology of skin lesions with warty appearance in renal allograft recipients.

Warts are common in renal allograft recipients, with a reported incidence of warts ranging from 24% to 100%. These patients also demonstrate an accelerated course from wart to carcinoma. Although the histologic appearance of common warts is predictable in immunocompetent patients, this has not been shown in renal allograft recipients. The purpose of the study was to evaluate the histopathologic findings of warty lesions in renal allograft recipients and to determine the degree of dysplasia or malignant transformation in such lesions. We examined 55 renal allograft recipients for warty lesions. We obtained biopsy specimens from 50 lesions that appeared on clinical examination to be common warts and evaluated their histopathologic features. Median time from transplantation was 49 months (<5 years). All patients were treated with cyclosporine, azathioprine, and prednisolone. Among 55 renal allograft recipients, 17 patients (30.9%) had warty lesions. Forty-seven lesions (94%) showed changes of verruca vulgaris on histologic examination, and only three lesions (6%) showed warts with mild dysplasia. No malignant transformation was reported. Our findings were in contrast to a previous, similar study. This may be attributable to the relatively short period from transplantation to biopsy in our patients.