Mucosal swabs detect HPV in laryngeal papillomatosis patients but not family members

Seven patients, aged 2-7 years, with active recurrent respiratory papilloma tosis (RRP) attending the University of Michigan Pediatric Otolaryngology C linic were studied to determine if human papillomavirus (HPV) is harbored i n sites of the upper aerodigestive tract other than in the laryngeal papill oma itself. We also determined if close family members had detectable virus in their oral cavities. Noninvasive swabs of buccal mucosa, posterior phar ynx, nasal vestibule, and tonsillar pillar of patients, as well as buccal m ucosa and posterior pharyngeal swabs of family members were studied. Swabs of the patients' papillomas served as the positive controls. HPV was detect ed using polymerase chain reaction (PCR amplification and Southern hybridiz ation techniques. Six of seven patients had detectable HPV in papilloma and endolaryngeal swabs. Four were HPV type 6, and two were HPV type Il. The p atient whose swab was negative for HPV was found to be biopsy negative for papilloma 3 weeks after a single laser excision which was performed 6 month s prior to the endolaryngeal swab. HPV types 16, 18 and 31 were not found i n any of the patients. No swabs from other sites in patients or family memb ers were HPV positive despite the presence of adequate DNA in the swabbed m aterial for successful amplification of beta-actin sequences. The absence o f HPV (other than in the papilloma itself) in the upper aerodigestive tract of patients and caregivers is consistent with the absence of reported case s of horizontal transmission to siblings or other family members. The findi ngs are also consistent with the conventional view that juvenile respirator y HPV is transmitted vertically from vaginal condylomas in the mother. (C) 2000 Elsevier Science Ireland Ltd. All rights reserved.