ULTRASTRUCTURE AND HUMAN PAPILLOMAVIRUS DNA IN PAPILLOMATOSIS OF EXTERNAL AUDITORY-CANAL

Background. A viral etiology has been suspected in papillomatosis of t he external auditory canal (PEAC), but virus particles have not been d etected so far, although they are easily demonstrable in skin warts. T he purpose of the study was to solve this discrepancy by the use of po lymerase chain reaction (PCR). Materials and Methods. Specimens from t he external auditory canal of 14 patients with PEAC, but no human papi lloma virus infection of the genital areas, were examined histological ly by light and electron microscopy, as well as by PCR to detect viral DNA. Results. Histologically, papillomatosis was present in all speci mens; Vacuolated cells were found in the upper part of the stratum mal pighii in five cases. On electron microscopy, the numbers of perichrom atin 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.