Nodular amyloidosis treated with a pulsed dye laser.

BACKGROUND Nodular amyloidosis is a rare form of primary localized cutaneous amyloidosis which is characterized by single or multiple nodules located on the extremities, trunk, genitalia, or face. OBJECTIVE To determine the clinical and histologic response of nodular amyloidosis to pulsed dye laser treatment. METHODS Biopsy-proven amyloid nodules were treated with a 585-nm pulsed dye laser (average fluence 5.25 J/cm2; 10 mm spot) at 6- to 8-week time intervals. Clinical and histologic examination of laser-irradiated nodules were performed before and 6 weeks after the final laser treatment. RESULTS Clinical improvement in the color, size, and pliability of nodules was noted and maintained for 6 months. Histologic examination revealed decreased inflammation and improvement in dermal collagen after laser irradiation. CONCLUSIONS Since amyloid fibrils may be formed in association with dermatan sulfate-an essential matrix component in collagen fiber formation, it is postulated that the improvement seen in amyloid nodules after pulsed dye laser treatment may be attributed to a mechanism similar to that seen with hypertrophic scars.