Association of human papillomavirus subtype and clinical course in respiratory papillomatosis.

The relationship of human papillomavirus type 6 (HPV-6) subtypes to the clinical manifestations of respiratory papillomatosis was investigated. DNA was isolated from biopsy specimens of 21 patients and the viral genome analyzed by molecular hybridization. Four subtypes, designated HPV-6c through HPV-6f, were distinguishable by restriction endonuclease cleavage patterns of the viral genome. Patient records were reviewed to identify associations between viral subtype and sex, race, age at onset of papilloma, duration of disease, frequency of operations, history of tracheotomy and anatomical extension of papilloma. HPV-6c was present in 13 cases which were characterized by extensive anatomical spread of disease, higher frequency of operations, and a need for tracheotomy. HPV-6d occurred in 4 black patients with juvenile onset papilloma. HPV-6c was found in 2 white patients--1 with juvenile onset and 1 with adult onset papilloma. HPV-6f was identified in 2 white patients with adult onset disease.