Hematoporphyrin monomethyl ether-mediated photodynamic therapy temporarily relieves severe pruritis from phakomatosis pigmentovascularis: A case report.

Phakomatosis pigmentovascularis (PPV) is a rare congenital syndrome characterized by (a) capillary malformations, such as port-wine stain (PWS), and (b) pigmented lesions, such as pigmented trichoepidermal nevus, café-au-lait spots, and dermal melanocytosis with or without systemic damage. Severe pruritus has not previously been reported among PPV patients. Here, we report a pediatric case of PPV with severe pruritus, which was refractory to various long-term oral antiallergic agents and topical tacrolimus but was temporarily responsive to hematoporphyrin monomethyl ether-mediated photodynamic therapy (HMME-PDT). HMME-PDT is the latest technology used in treating PWS following the basic principle of targeted photodynamic destruction of the vascular wall of the lesion. Furthermore, many studies have confirmed the safety and efficacy of HMME-PDT for PWS in both adults and children. Specific pathophysiologic mechanisms and treatment methods must be further explored to advance our understanding of the disease and improve the quality of life in PPV patients.