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A randomized controlled study of low-dose UVA1, medium-dose UVA1, and narrowband UVB phototherapy in the treatment of
Alexander Kreuter1, Julia Hyun, Markus Stücker
1Department of Dermatology and Allergology, Ruhr-University Bochum, Bochum, Germany. a.kreuter@derma.de
Background:
In previous trials, UV therapy has been demonstrated to be effective in the treatment of localized scleroderma (LS). To date, a randomized comparison study to evaluate the efficacy and safety of different, commonly used phototherapeutic modalities in LS is still outstanding.
Objective:
The aim of this study was to compare the safety and efficacy of low-dose (LD) UVA1, medium-dose (MD) UVA1, and narrowband (NB) UVB phototherapy in the treatment of LS.
Methods:
Sixty four patients with LS were consecutively included in a prospective, open, randomized controlled 3-arm study. Severity of LS was determined by means of a clinical score, and clinical improvement was also monitored by histopathologic analysis and 20-MHz ultrasound.
Results:
A total of 27 patients were treated with LD UVA1 (20 J/cm2), 18 patients received MD UVA1 (50 J/cm2), and 19 patients were treated with NB UVB dependent on their skin type. Phototherapy was performed 5 times weekly for 8 weeks. Two of the 64 patients included in this trial discontinued therapy. Skin status significantly improved in all patients who finished the treatment protocol, resulting in a reduction of the clinical score in all groups (LD UVA1, 7.6-5.0 [P < .001, 95% confidence interval 1.6-3.4]; MD UVA1, 11.1-6.6 [P < .001, 95% confidence interval 2.5-6.2]; NB UVB, 7.3-4.9 [P < .001, 95% confidence interval 1.6-3.2]). The reduction of the score was accompanied by an improvement of the visual analog scale for itching and tightness, histologic score, and 20-MHz ultrasound. MD UVA1 was significantly more effective than NB UVB (P < .05). There were no significant differences between LD UVA1 and NB UVB and the former and MD UVA1 (P > .05).
Limitations:
We had a relatively small study sample and nonblinded assessment of primary outcome.
Conclusion:
Phototherapy, as previously reported in several noncontrolled trials, is an effective therapeutic option in LS, with a favorable risk/benefit ratio. UVA1 phototherapy should be considered among the first approaches in the management of LS.
