Nonhealing Erosions With Granulation Tissue in the Treatment of Acne Lesions During Isotretinoin Therapy

To the Editor.—  We read with interest the article by Exner et al¹ in the October Archives that described pyogenic, granuloma-like acne lesions that occurred during isotretinoin therapy. We² also noted this unusual reaction and reported it in the Mayo Clinic Proceedings. This reaction occurred in three of the patients we treated who had the most severe acne lesions that began to appear at approximately one month of therapy. These painful, nonhealing erosions with granulation tissue persisted until completion of therapy. They healed when isotretinoin therapy was discontinued; therefore, they are likely related to vitamin A—like side effects such as epidermal thinning or delayed epithelialization.We believe that these lesions are better described as persistent erosions with granulation tissue and are not actually pyogenic granulomas. The biopsy specimen from case 3 of Exner et al¹ is more consistent with granulation tissue than with a true pyogenic granuloma.