Human papillomaviruses (HPV) are epitheliotropic viruses, with some types suggested to be associated with skin cancer. In this study, swab samples collected from five different sites on the skin of renal transplant recipients, dialysis patients, and age-and sex-matched healthy controls were analyzed for HPV DNA by a newly designed PCR test. Most individuals were found to have asymptomatic HPV infections; more specifically, 94% of the renal transplant patients, 82% of the dialysis patients, and 80% of the healthy controls were positive for HPV DNA. The multiplicity of the HPVs detected was astounding: 20 previously described and 30 putatively new types were identified by cloning and sequencing of 33 samples from 13 individuals. These results demonstrate that normal human skin harbors an array of papillomaviruses, most of them previously unknown.To date, 85 different genotypes of the human papillomaviruses (HPV) have been fully characterized. In addition to being the causative agents of common skin warts, there is evidence that certain types of HPV play a role in the pathogenesis of skin cancer associated with the rare hereditary disease epidermodysplasia verruciformis (EV) (22, 27), and they are therefore designated EV-associated HPV.Renal transplant recipients given immunosuppressive therapy for long periods of time have an increased incidence of cutaneous neoplasia (2,10,29). Also, more than 90% of kidney recipients develop skin warts and 40% develop skin cancer within 15 years of transplantation, a 50-to 100-fold increase compared to the general population (7), and EV-associated HPV types have been found in skin tumors from such patients (5,12,16,21,28). Interestingly, EV HPV types have also been detected in hairs plucked from normal skin of 94% of renal transplant recipients (8) and 67% of healthy controls (9), and in another study (1), 35% of biopsy specimens of normal skin obtained during cosmetic surgery were positive for HPV DNA.In a recent report (20), we presented a PCR test that holds promise as a potent tool for exploring HPV both in skin tumors and in normal skin. In the present investigation, we used the test to study the presence of HPV at various sites on normal skin of both renal patients who were or were not on immunosuppression and matched healthy controls, and there is a serendipitous aspect to the results.
MATERIALS AND METHODSSubjects. We studied 52 of about 130 renal transplant recipients being followed up at the outpatient clinic of nephrology of Malmö University Hospital, Malmö, Sweden. The median time since transplantation was 5 years and 2 months, and the range was 2 months to 26 years. Also included in the study were 28 of the 67 patients being treated at the Dialysis Unit; the median length of dialysis treatment was 2 years and 5 months (range, 1 month to 14 years). All of the transplant and dialysis patients were randomly selected, and a sex-and age-matched healthy control was recruited for each of the patients. The age range of the individuals in the three groups was 21 to 80 years,...