Efficacy and safety of 88% phenol application versus cryotherapy in repigmentation of idiopathic guttate hypomelanosis: A prospective study

Abstract

Background: Idiopathic guttate hypomelanosis (IGH) is a common, acquired dermatosis characterized by multiple, round or oval, hypopigmented to depigmented macules. A variety of therapies with variable success are described, despite that, the treatment remains still unsatisfactory and a therapeutic challenge for the treating specialist. Objective: The objective of this study is to compare the safety and efficacy of 88% phenol application and cryotherapy in repigmentation of IGH macules. Materials and Methods: A total of 30 patients with more than 10 IGH macules were selected. For each enrolled patient, 88% phenol was applied to 5 IGH macules and single cryotherapy for 3–5 s was applied for another 5 IGH macules once in a month till the repigmentation for maximum of 3 applications. Patients were assessed monthly for 3 months for the side effects and improvement in pigmentation. The degree of improvement in pigmentation was assessed using a grading system, 75% - excellent response (Grade-4). Results: A total of 25 patients completed the study. At the end of the treatment period, out of 125 macules treated with short contact cryotherapy 75 (60%) macules showed excellent response and 20 (16%) macules showed good response. In phenol group, out of 125 macules 37 (29.6%) and 29 (23.2%) macules showed excellent and good improvement in pigmentation respectively, with P < 0.05. Side effects such as persistent scabbing, ulceration were more common with 88% phenol application compared to cryotherapy. Conclusion: Short contact cryotherapy of 3–5 s was found to be more efficacious and safe compared to therapeutic wounding with 88% phenol in inducing pigmentation of IGH macules.

Keywords

• 88% phenol
• cryotherapy
• idiopathic guttate hypomelanosis