Treatment of subclinical intraurethral human papilloma virus infection with interferon alfa-2B

Abstract

Anogenital human papilloma virus (HPV) infection represents a growing concern among physicians in the United States. An intraurethral reservoir of the virus has been suggested as a possible source for reinfection between sexual partners, and may contribute to the increase in the number of affected individuals. Treatment reports of intraurethral HPV infection with adequate follow-up have been lacking. Our goals in this study were to identify the patients with cytologic evidence of HPV intraurethral infection, and to attempt treatment with intraurethral instillations of interferon alfa-2b. Eighty-nine men with anogenital lesions or known exposure to HPV underwent cytologic examination using a urethral swab after all visible disease was adequately treated. Sixteen patients with positive cytology results were treated with weekly instillations of 25 million U of interferon alfa-2b solution for 6 weeks. Urethral cytology was monitored at 2 and 6 weeks post-treatment, as well as every 3 months thereafter up to a year. Those who had a recurrence during the study were retreated with a 6-week course using 50 million U per instillation. Patients were monitored for possible side effects. Seventeen (19%) of 89 patients who entered the study had urethral cytology positive for HPV infection with no evidence of visible disease. Seven (41%) of these 17 patients did not show external (meatal or skin) manifestations of the disease. Fourteen of 16 (88%) men who underwent the therapy were followed for an average of 11.8 months. Nine of those 14 (64%) remained disease free throughout the follow-up. Of the 5 who had a recurrence, 3 were successfully retreated, with a mean of 7.2 months of disease-free follow-up after the second course. No adverse effects of the treatment were noted by blood testing, semen analysis, and patient report. The urethra is a significant HPV reservoir and should be investigated in patients exposed to the virus. Interferon is a potentially safe and effective treatment option for intraurethral HPV.