Eczematous dermatitis after vascular laser therapy: a report of two cases.

Eczematous dermatitis was found in two port wine stain (PWS) lesions in two different individuals following variable pulsed 532-nm laser therapy. Both of the individuals described in this report had received low-dose superficial X-ray several years prior to the development of the eczematous dermatitis. The eczematous dermatitis in the PWS lesions was characterized by oozing, crusting, and pruritus, which showed a tendency to expand to other sites when exacerbated. Treatment with topical corticosteroid ointments produced some temporary improvement, but the dermatitis in both cases recurred when the topical medications were stopped. The mechanism of action for the development of an eczematous dermatitis in a PWS remains unclear, but may be related to multiple factors including abnormal hemodynamic forces resulting from the malformed vessels, an abnormal production of cytokines, local pathophysiological and immunological changes resulting from either the X-ray therapy or the laser therapy, and atopic constitution inherent in these individuals. These hypotheses and ideas need further study for additional insight into this rare, but reported adverse event.