RESUMO
IMPORTANCE: Fractionated, ultrapulsed carbon dioxide (CO2) laser therapy is a powerful tool for the treatment of scars. Common adverse effects of this therapeutic modality have been previously documented. We describe 2 unreported adverse effects of ultrapulsed CO2 laser treatment of mature scars in a patient previously treated with silver-impregnated dressings. OBSERVATIONS: A teenage survivor of toxic epidermal necrolysis presented with faint but diffuse dyschromia clinically and histologically consistent with localized argyria secondary to silver-impregnated dressings used years earlier. The patient was subsequently treated with fractionated CO2 for her scarring, but her hyperpigmentation worsened with each treatment. A subsequent biopsy specimen revealed a zone of dystrophic calcification with adjacent pseudo-ochronotic fibers that were not appreciated on biopsy specimens taken before CO2 laser treatment, suggesting unique complications not previously reported. CONCLUSIONS AND RELEVANCE: We present 2 unique complications secondary to ultrapulsed, fractionated CO2 laser treatment in a patient previously treated with silver-impregnated dressings: (1) the appearance of pseudo-ochronotic fibers in areas of worsening pigmentation and (2) evidence of dystrophic calcification limited to columns of fractionated laser ablation. Therefore, a history of argyria or treatment with silver-impregnated dressings should be considered before treatment with fractionated CO2 lasers.