About 7 percent of the general population tests positive for oral human papillomavirus (HPV) at any given time, but oral HPV is found almost universally among adults with recurrent respiratory papillomatosis (RRP), a rare disease of the larynx caused by HPV infection.
This discovery is among several recent insights of researchers at the Voice Center at NYU Langone that may contribute to the development of more effective treatment strategies for patients with RRP.
Although benign, RRP has no cure, is associated with significant morbidity, and typically requires multiple surgical interventions to keep symptoms at bay. Knowing that patients with RRP also have active HPV DNA in the oral cavity, researchers investigated the possibility that these patients have more global immune system deficiencies than the general population. Since HPV exposure is ubiquitous, the investigators looked for factors that underlie the acquisition of RRP in otherwise healthy patients.
Oral DNA Samples Collected for Trial
In a multicenter study published in December 2014 issue of Laryngoscope, Ryan C. Branski, PhD, associate professor of otolaryngology and associate director of the Voice Center, Milan R. Amin, MD, associate professor of otolaryngology, chief of the Division of Laryngology, and director of the Voice Center, and colleagues collected oral DNA samples from 27 adults with RRP and found that 96 percent tested positive for oral HPV infection. In addition, 67 percent of samples taken from long-term sexual partners of RRP patients tested positive for oral HPV. “These patients appear to have diffuse viral infection along the upper aerodigestive tract,” says Dr. Branski. Although RRP is classified as a sexually transmitted disease, whether the infection spreads solely through sexual contact is unclear. One possibility is that the virus is transmitted during birth—as is hypothesized in juvenile-onset RRP—and remains latent until adulthood.
Interestingly, another multicenter study led by the Voice Center, published in October 2014 in Laryngoscope, found that adult RRP patients are no different from matched controls with regard to birth history, suggesting that the juvenile and adult versions of the disease have distinct routes of transmission. In addition, contrary to previous studies, this study’s data indicate that laryngeal HPV may be transmitted via mouth-to-mouth, rather than orogenital, contact.
Although not the primary goal of the study, the researchers uncovered some compelling demographic data indicating that RRP appears to predominantly affect relatively healthy, affluent, Caucasian males. In contrast, no gender disparity has been found among children with RRP.
Counseling Patients is Critical
In a subsequent article, published in January 2015 in JAMA Otolaryngology–Head & Neck Surgery, Voice Center researchers offer guidance to clinicians on how to counsel patients, who often have myriad questions about disease acquisition, course, and transmission. Among the researchers’ recommendations: inform patients that their RRP may be related to a new or latent HPV infection.
Dr. Amin and Dr. Branski are expanding on their previous work. Supported by a grant from the American Society of Pediatric Otolaryngology, the team is seeking to determine the duration of oral HPV infection in RRP patients. The researchers will analyze DNA extracted from oral rinse samples taken every three months in order to determine whether oral HPV infection persists beyond six to seven months, which is the typical duration in the general population.