Koebnerization phenomenon after broadband light therapy in a patient with cutaneous sarcoidosis

ALA: aminolevulinic acid BBL: broadband light IPL: intense pulse light Nd:YAG: neodymium-doped yttrium aluminium garnet PDT: photodynamic therapy INTRODUCTION Sarcoidosis is an inflammatory disease characterized by noncaseating epithelioid cell granulomas. Skin involvement is seen in approximately onequarter of patients. Multiple cutaneous variants in sarcoidosis include lupus pernio, Lofgren syndrome, Darier-Roussy, and erythematous papules and nodules arising within pre-existing scars. Treatment consists of potent topical steroids, intralesional corticosteroids, systemic corticosteroids, antimalarial agents, and methotrexate. More recently, in-office treatments involving light-based therapies such as photodynamic therapy (PDT), intense pulse light (IPL), and broadband light (BBL) are being used. Additionally, vascular laser treatments including the pulse dye laser (PDL) and fractionated resurfacing lasers have produced significant improvement in cutaneous sarcoidosis. As with other inflammatory skin conditions, such as lichen planus, vitiligo, and psoriasis, sarcoidosis can exhibit the koebnerization phenomenon. Laser surgeons need to be aware of this potential complication when treating cutaneous sarcoidosis. Cases of adverse reactions to lightand laser-based devices are rare but are characterized by crusting, scabbing, blistering, scarring, hyperpigmentation, hypopigmentation, bruising, or incomplete response. We present a case of a bullous reaction with koebnerization after BBL therapy in a patient with good response in the past to BBL treatments. We also review the literature regarding various light-based treatments for cutaneous sarcoidosis.