Prediction of Treatment Response of Verruca Vulgaris Based on Lesion Hardening

Background: Verruca vulgaris is a common cutaneous viral infectious disease caused by human papilloma virus (HPV). The main treatment modalities are cryotherapy, immunotherapy, laser therapy, intralesional injection of bleomycin, and salicylic acid therapy. However, there is no definitive tool for predicting clinical improvement or treatment response. Objective: This study was designed to evaluate clinical treatment response according to the hardness of verruca vulgaris skin lesions. We developed a new prediction tool called the “hardening sign” that divides the course of treatment into four categories based on inspection and palpation. Methods: We conducted a retrospective medical chart review of patients who visited Hanyang University Guri Hospital between January 2016 and January 2017 and were clinically diagnosed with verruca vulgaris. We divided the patients into four groups according to the grade of rigidity of their lesions. Results: Forty-seven patients (24 male and 23 female) were identified. The mean age at diagnosis was 17.2±8.5 years, and the mean duration of treatment was 28.8±27.7 weeks. The mean number of hospital visits was 16.5±12.4. Eleven patients underwent only cryotherapy, while 36 patients underwent combined cryotherapy and immunotherapy. We observed significantly shorter durations of treatment for patients with higher grades of hardening. There was no correlation between the hardening grade and the number of treatments required for patients to be completely cured. Conclusion: This study suggests that the therapeutic response of verruca vulgaris warts to cryotherapy can be easily predicted by careful consideration of the “hardening sign”. (Korean J Dermatol 2020;58(5):324∼329)