Ultrastructure and human papillomavirus DNA in papillomatosis of external auditory canal.

BACKGROUND

A viral etiology has been suspected in papillomatosis of the external auditory canal (PEAC), but virus particles have not been detected so far, although they are easily demonstrable in skin warts. The purpose of the study was to solve this discrepancy by the use of polymerase chain reaction (PCR).

MATERIALS AND METHODS

Specimens from the external auditory canal of 14 patients with PEAC, but no human papilloma virus infection of the genital areas, were examined histologically by light and electron microscopy, as well as by PCR to detect viral DNA.

RESULTS

Histologically, papillomatosis was present in all specimens. Vacuolated cells were found in the upper part of the stratum malpighii in five cases. On electron microscopy, the numbers of perichromatin and interchromatin granules were increased, but no viral granules were observed. In all specimens, DNA of HPV 6 was detected using PCR, but there was no evidence of DNA of other HPV.

CONCLUSIONS

Papilloma of the external auditory canal is produced by infection with HPV 6.