Histopathology and immunohistochemistry of cutaneous lupus erythematosus after pulsed dye laser treatment.

BACKGROUND: Cutaneous lupus erythematosus (CLE) is a heterogeneous autoimmune disorder with a wide range of skin manifestations. Current treatment options include topical and systemic approaches. Few controlled prospective studies have been performed using the pulsed dye laser (PDL). Based on previous experience that supported the efficacy of PDL treatment of CLE, we decided to study the histological changes induced by PDL.

OBSERVATIONS: A prospective study was performed on nine patients with histologically confirmed CLE treated with PDL. Biopsies were taken before, immediately after, and 4 weeks after treatment and stained with hematoxylin and eosin and with commercially available antibodies to intercellular adhesion molecule (ICAM)-1 and vascular cell adhesion molecule (VCAM)-1. Evaluation after PDL treatment showed a significant reduction of the dermal lymphocytic infiltrate in six of nine patients (66.7%) and an important reduction of the basal damage in six of seven patients (85.7%). Other epidermal changes improved in four of six patients (66.7%). Mucin deposition persisted in two patients. ICAM and VCAM expression was reduced in seven of seven patients (100%) and five of six patients (83.3%) (p<.05). Clinical improvement was present in eight of nine patients (88.9%), without side effects.

CONCLUSIONS: PDL therapy is an effective treatment for CLE. Immunohistologic improvement has been confirmed in this study.