Medium-dose UVA1 Research Articles

Carcinogenic risk in patients treated with UVA-1 phototherapy: A 5-year retrospective study.

UVA-1 phototherapy was first used to treat atopic dermatitis and afterwards to several other skin diseases. The contribution of UVA-1 in human photocarcinogenesis, skin photoaging, immune suppression, and hyperpigmentation is now well established. The actual contribution of UVA-1 radiation to the development of malignant melanoma (MM) in humans cannot be excluded. The aim of the study is to evaluate the risk of developing skin cancers (non-melanoma skin cancers (NMSCs) and MM) in patients treated with UVA-1 phototherapy with a 5-year dermatological follow-up. We conducted a retrospective cohort study with 31 patients with morphea and atopic dermatitis treated with medium dose UVA-1 phototherapy (34 J/cm2). All enrolled patients underwent an oncologic prevention visit annually with a 5-year follow-up with clinical evaluation of the entire skin surface. During the 5-year follow-up, we recorded a case of basal cell carcinoma (BCC) in the cervical region and one case of MM on the back (pT1a). In both cases, the patients were female and affected by morphea. The Glogau 3 group is prevalent (42%), which is consistent with moderate to severe aging; the data appear to be compatible with the age. This study attests that medium-dose UVA-1 phototherapy does not increase the risk of developing skin tumors and that UVA-1 phototherapy is not a worsening factor of facial photoaging. The main limitation of the study is the small sample size, avoiding to obtain statistically significant values. It was not possible to analyze individually the actual daily sun exposure during the 5-year observation period and to correlate it in terms of time and tumor development. Further studies with large sample sizes will be needed to confirm our data. Our study reaffirms how the dermatological examination performed annually is essential in the follow-up of patients undergoing this type of therapy.

Definition of the Clinical Characteristics of Patients with Moderate and Severe Atopic Dermatitis for Whom Narrow-Band UVB (NB-UVB) and Medium-Dose UVA1 Phototherapies Are Still Valuable Treatment Options at the Age of Biologics.

Narrow-band (NB) UVB and UVA1 have been successfully used for the treatment of atopic dermatitis (AD) since the 1980s, but the clinical indications for their use "at the age of biologics" remain to be assessed. From 2013 to 2017, 145 patients underwent a first treatment cycle with phototherapy. They achieved a median final EASI score of 9.90 with UVA1 and 13.70 with NB-UVB. The rates of patients achieving an IGA score of 0/1 persistent for at least 6 months were 33% with UVA1 and 28% with NB-UVB, and the rates with an EASI90 improvement were 10.9% with UVA1 and 11.0% with NB-UVB. The cut-off baseline EASI values for a good probability to achieve a 0/1 IGA were 24.4 with UVA1 and 24.7 with NB-UVB. A 0/1 IGA persistent for at least 6 months was more likely to be achieved by patients with a history of flares interspersed with periods of mild or no disease. From 2018, we only enrolled patients with the above-mentioned characteristics. The number of treated patients was lower, but the final EASI score, the rate of patients achieving IGA 0/1 persistent for at least 6 months, and EASI90 were significantly higher. Medium-dose UVA1 and NB-UVB phototherapies remain useful for the treatment of AD patients with a baseline EASI score lower than 24.4 and 24.7, respectively, and a medical history of flares followed by prolonged periods of complete or near-complete remission.

Clinical and laboratory characterization of patients with localized scleroderma and response to UVA-1 phototherapy: In vivo and in vitro skin models.

Localized scleroderma (LS) is a rare disease leading to progressive hardening and induration of the skin and subcutaneous tissues. LS is responsive to UVA-1 phototherapy, though its exact mechanism of action dermal fibrosis is yet to be fully elucidated. We aimed to investigate the molecular changes induced by UVA-1 rays in human primary fibroblasts cultures. A total of 16 LS patients were treated with medium-dose UVA-1 phototherapy. At baseline, during and after therapy, Localized Scleroderma Assessment Tool, Dermatology Life Quality Index and lesions' staging and mapping were performed along with high-frequency ultrasound (HFUS) examination for dermal thickness assessment. Gene expression analysis for 23 mRNA transcripts, in vitro UVA-1 irradiation and viability tests were realized on lesional fibroblasts' primary cultures, before and 3 months after therapy. The dermal thickness, the LoSCAT and the DLQI progressively decreased starting from the last phototherapy session up to the 6 and 9 month follow-ups (-57% and -60%, respectively). Molecular gene analysis (rt-PCR) revealed that UVA-1 phototherapy exerts multiple effects: the activation of specific anti-fibrotic pathways (e.g., overexpression of CTHRC1 and metalloproteases 1, 2, 7, 8, 9, 12, suppression of TIMP-1), the downregulation of peculiar pro-fibrotic pathways (e.g., downregulation of TGF-ß, TGF-ßrII, Grb2, SMAD 2/3, TNRSF12A, CTGF) through a significant overexpression of IL-1ß; the stabilization of collagen synthesis acting on genes COL1A1, COL3A1, COL8A1, COL10A1, COL12A1. UVA-1 phototherapy adds significant benefits in local tissue remodeling, rebalancing the alteration between pro-fibrotic and anti-fibrotic pathways; these changes can be well monitored by HFUS.

The impact of medium dose UVA1 phototherapy on pruritus, DLQI and SCORAD index in patients with atopic dermatitis.

IntroductionAtopic dermatitis (AD) is featured by pruritus, which causes diminished quality of life. Little clinical data exists concerning the use, efficacy and side effects of UVA1 phototherapy in AD patients.AimTo determine the effectiveness of medium-dose UVA1 phototherapy in AD treatment.Material and methodsThirty-six patients with AD were irradiated with medium-dose UVA1 (45 J/cm2) as monotherapy for 4 weeks for a total of 20 sessions (daily irradiations during weekdays only). Clinical status was evaluated with the visual analogue scale for pruritus, Dermatology Life Quality Index (DLQI) for evaluating general well-being and the SCORAD index. All parameters were measured twice: before and after phototherapy.ResultsUVA1 phototherapy resulted in a significant (p < 0.001) decrease in pruritus, improvement in DLQI (p < 0.001) and SCORAD (p < 0.001). Before phototherapy, the intensity of pruritus and SCORAD index correlated with DLQI (r = 0.34, p < 0.05 and r = 0.61, p < 0.05, respectively). Similarly, after irradiation, pruritus correlated with DLQI, and SCORAD index correlated with DLQI (r = 0.51, p < 0.05 and r = 0.55, p < 0.05, respectively). No severe adverse effects were noted during the study.ConclusionsPhototherapy with medium-dose UVA1 irradiation exerts a significant antipruritic effect, decreases the severity of the disease and improves the quality of life of AD patients. This technique can therefore be used as a safe and effective treatment method.

Interventions for morphea.

Interventions for morphea.

Medium-dose ultraviolet A1 phototherapy improves SCORAD index and increases mRNA expression of interleukin-4 without direct effect on human β defensin-1, interleukin-10, and interleukin-31.

Effectiveness of ultraviolet (UV)A1 in flares of atopic dermatitis (AD) is thought to influence the expression of cytokines involved in its pathogenesis. The aim of the study was to investigate whether mRNA expression of human β defensin-1 (hβD-1) correlates with that of interleukin (IL)-4, IL-10, and IL-31 in skin lesions in AD before and after UVA1 phototherapy, to determine whether UVA1 decreases the expression of the aforementioned mediators, and to confirm whether changes in mRNA expression correspond with the clinical efficacy of UVA1. Twenty-five patients with AD underwent medium-dose UVA1 phototherapy. Before and after UVA1, biopsies from acute skin lesions were studied using reverse transcription and real-time polymerase chain reaction. Levels of mRNA hβD-1 correlated with those of IL-10 and IL-31, levels of IL-4 mRNA correlated with those of IL-10 and IL-31, and IL-10 expression correlated with that of IL-31, both before and after UVA1. Phototherapy with UVA1 improved SCORing of Atopic Dermatitis (SCORAD) values, decreased pruritus, and increased expression of IL-4. After UVA1, no difference was found in the mRNA expression of other molecules. The SCORAD index did not correlate with the expression of any examined mRNA either before or after UVA1. hβD-1, IL-4, IL-10, and IL-31 are expressed in acute skin lesions in AD, and their levels correlate with each other. UVA1 improves SCORAD and pruritus and increases the expression of IL-4 without direct effect on other molecules.

Phototherapy for atopic dermatitis.

The aim of these guidelines is to review the available published literature regarding the effectiveness of phototherapy and photochemotherapy in atopic dermatitis and put forward recommendations regarding their use in atopic dermatitis. A literature search was performed to collect data from PubMed, EMBASE, and the Cochrane Library published till March 2014. Keywords used were "phototherapy", "photochemotherapy", "NB-UVB", "BBUVB", "PUVA", "UVA1", "atopic dermatitis", and "atopic eczema". Systematic reviews, meta-analysis, national guidelines, randomized controlled trials, prospective open label studies, and retrospective case series in English literature mentioning use of above-mentioned keywords were reviewed. Six hundred and eighty eight studies were evaluated, 38 of which fulfilled the criteria for inclusion in the guidelines. Both UV1 and narrow-band UVB are effective in significantly decreasing the eczema severity although UV1 may be preferred in acute flares and narrow-band UVB in chronic eczema, especially in adults (Level of evidence 1+, Grade of recommendation A). Among various doses of UVA1, medium dose UVA1 may be preferred over others as its efficacy is similar to high dose and better than low dose UVA1 phototherapy. Narrow-band UVB is preferred to broad-band UVB (Level of evidence 1+, Grade of recommendation A). Medium-dose UVA1 is similar in efficacy to narrow-band UVB (Level of evidence 1+, Grade of recommendation A). In children, despite its efficacy, narrow-band UVB phototherapy should be used only as a second line therapy due to its potential for long-term adverse effects (Level of evidence 2+, Grade of recommendation B).

Interventions for morphea

Interventions for morphea

UV-A1 Phototherapy vs Clobetasol Propionate, 0.05%, in the Treatment of Vulvar Lichen Sclerosus

Topical corticosteroids are the current first-line therapy for vulvar lichen sclerosus (VLS). UV-A1 phototherapy may be a promising alternative treatment option, but controlled studies are lacking. To compare the efficacy of high-potent topical corticosteroids with UV-A1 phototherapy in the treatment of VLS. A 2-arm randomized clinical trial was conducted at a university hospital dermatology department according to the intention-to-treat principle with last observation carried forward. The study population comprised 30 female patients with VLS. Treatment of VLS with clobetasol propionate, 0.05%, ointment applied once daily for 3 months or medium-dose UV-A1 (50 J/cm²) home-based phototherapy, performed 4 times weekly for 3 months. Mean relative reduction of the total clinician's score (TCS) was considered the primary outcome measure. Secondary outcome measures included the reduction of pruritus and burning and/or pain according to a visual analog scale (VAS), a health-related quality of life score (Skindex-29), 20-MHz ultrasonography, and histopathological analysis before and after 3 months of therapy. Fifteen patients were randomized in each treatment arm, and 2 patients dropped out in both treatment arms. After therapy, both therapies resulted in a significant decrease in mean TCS (51.4% [95% CI, 39.7% to 63.0%] for clobetasol ointment [P < .001] and 35.6% [95% CI, 18.2% to 53.1%] for UV-A1 phototherapy [P = .006]). No significant difference was found between both treatments (P > .05). The Skindex-29 (mean difference [MD], 29.6 [95% CI, 7.9 to 51.2] [P = .009]) and the VAS score for pruritus (MD, 4.6 [95% CI, 1.5 to 7.7] [P = .005]) and burning and/or pain (MD, 4.2 [95% CI, 1.9 to 6.6] [P = .001]) significantly decreased after clobetasol treatment. After UV-A1 phototherapy, the VAS score for burning and/or pain (MD, 3.2 [95% CI, 0.7 to 5.7] [P = .01]) was also significantly reduced; however, there was no significant reduction in pruritus (MD, 2.1 [95% CI, 0.5 to 3.7] [P = .16]) and in the Skindex-29 score (MD, 4.9 [95% CI, -12.6 to 22.4] [P > .99]). A significant reduction of the corium thickness and a significant increase in dermal density in 20-MHz ultrasonography as well as significant histopathological reduction of the inflammatory infiltrate was observed after clobetasol treatment but not after UV-A1 phototherapy. Although resulting in a significant clinical improvement, UV-A1 phototherapy was inferior to the current gold standard treatment with topical high-potent corticosteroids with respect to practicability, relief of itch, and improvement in quality of life. UV-A1 phototherapy may be considered a potential second-line treatment for VLS. clinicaltrials.gov Identifier: NCT01400022.

Photo(chemo)therapy in the management of atopic dermatitis: an updated systematic review with implications for practice and research

Photo(chemo)therapy is a common treatment modality in patients with atopic dermatitis (AD), but evidence on its effectiveness has not been recently systematically reviewed. To evaluate the effect of treatment with photo(chemo)therapy in patients with AD and to make treatment recommendations on basis of the evidence. We performed an electronic literature search in MEDLINE (OVID), EMBASE (OVID), the Cochrane Central Register of Controlled Trials (CENTRAL), Global Resource of EczemA Trials (GREAT) and prospective trial registers, complemented with a search of PubMed to find recent studies not yet available in OVID MEDLINE. All randomized controlled trials (RCTs) on phototherapy for the treatment of AD were considered for data extraction. Nineteen studies were included (905 participants). The identified RCTs were generally clinically and qualitatively heterogeneous. Therefore a formal meta-analysis was not feasible. Conclusions must be drawn carefully because of small sample sizes, varying study quality and sometimes the absence of direct comparisons, but on the basis of the included evidence, ultraviolet (UV) A1 and narrowband (NB)-UVB appeared the most effective treatment modalities for the reduction of clinical signs and symptoms. No difference between high-dose UVA1 and medium-dose UVA1 was seen. UVAB was shown to be more effective than UVA and broadband-UVB for the improvement of clinical symptoms, but not compared with UVA1. Other effective treatment options include full-spectrum light, psoralen plus UVA and balneophototherapy. No serious side-effects were reported. Phototherapy can be a valid therapeutic option for patients with AD. Based on the results of this review, preference is given to UVA1 and NB-UVB. Further well-designed, adequately powered RCTs are required.

Altered global methylation and hydroxymethylation status in vulvar lichen sclerosus: further support for epigenetic mechanisms

Epigenetics refers to functionally relevant changes in the genome other than those of DNA sequence that can lead to changes in gene expression or cellular phenotype. There is evidence that epigenetics is relevant in the pathogenesis of autoimmune diseases such as vulvar lichen sclerosus (VLS), as well as in cancer, including cutaneous squamous cell carcinoma, which is frequently associated with VLS. To study the global methylation and hydroxymethylation status in healthy controls and VLS lesions before and after long-term ultraviolet (UV)A1 treatment. We studied 12 controls and 10 patients with VLS who were treated with medium-dose UVA1 four times weekly for 3 months. Immunohistochemistry and mutation analyses (polymerase chain reaction) were performed for 5-methylcytosine (5mC), 5-hydroxymethylcytosine (5hmC), isocitrate dehydrogenases (IDHs) and the ten-eleven translocation (TET)2 enzyme. After 3 months of treatment, 5mC was significantly increased in VLS compared with baseline and controls. However, compared with controls 5hmC levels were significantly reduced in baseline VLS, but normalized after UVA1 treatment. Compared with controls, IDH1 expression was significantly higher in both treated and baseline VLS. By contrast, IDH2 levels were significantly reduced in baseline VLS compared with controls and UVA1-treated VLS. However, gene sequencing of the IDH1, IDH2 and TET2 genes did not reveal evidence of mutations. VLS is associated with altered expression of IDH enzymes and aberrant hydroxymethylation, indicating an epigenetic background for the pathogenesis of VLS. UVA1 phototherapy may cause normalization of 5hmC patterns, but also global DNA hypermethylation in VLS lesions, raising concerns with respect to an increased risk of photocarcinogenesis.

Ultraviolet A1 Phototherapy of Mycosis Fungoides

Ultraviolet A1 Phototherapy of Mycosis Fungoides

Effects of ultraviolet A (UVA)-1/UVA irradiation on type I collagen synthesis and matrix metalloproteinase 1 expression by fibroblasts from patients with localized scleroderma

Objective To evaluate the effects of UVA and UVA-1 irradiation on type I collagen （COL1A1） synthesis and matrix metalloproteinase 1 （MMP-1） expression by fibroblasts from patients with localized scleroderma （LS）. Methods Fibroblasts were isolated from the lesions of 6 patients with LS and normal skin of 4 healthy human controls followed by a primary culture in vitro. After 3 to 8 passages, the fibroblasts were irradiated with different doses of UVA-1 （0, 2.5, 5, 10, 20, 40 J/cm2） and UVA （5 and 20 J/era2）. After additional 24-hour culture, RNA was extracted from the cells followed by fluorescence-based quantitative reverse transcription PCR for the detection of MMP-1 and COL1A1 mRNA expression. Results Compared with control skin fibroblasts, LS-derived fibroblasts showed a higher expression level of COL1A1 but a lower level of MMP-1 （both P 〈 0.05）. The irradiation with UVA-1 of the tested doses （2.5-40 J/era2） had no significant influence on the expression of COL1A1 mRNA （all P 〉 0.05）, but significantly increased the expression of MMP-1 reRAN （all P 〈 0.05）. The effect of UVA on COL1A1 synthesis and MMP-1 expression appeared superior to that of UVA-1 at the same doses （5 and 20 J/cm2）. Conclusions UVA-1 irradiation can suppress the synthesis of COL1A1, but stimulate the expression of MMP-1, in LS-derived fibroblasts, and the effect of medium dose UVA-1 seems superior to that of low dose UVA-1. At same irradiation doses, UVA shows a stronger effect than UVA-1. Key words: Scleroderma, localized; Ultraviolet rays; Collagen type I; Matrix metalloproteinase 1

Effectiveness of medium‐dose ultraviolet A1 phototherapy in localized scleroderma

Recently, ultraviolet (UV) A1 phototherapy has been suggested as an effective treatment for localized scleroderma (LS); however, the optimal dose of UVA1 still has not been determined. We aimed to evaluate the therapeutic effectiveness of medium-dose (30 J/cm(2) ) UVA1 phototherapy and to show that 13MHz ultrasound is a valuable tool for assessing the results of UVA1 phototherapy in LS. Thirty-five patients with LS were treated with medium-dose (30J/cm(2) ) UVA1. In total, 30-45 treatments and 900-1350J/cm(2) cumulative UVA1 doses were evaluated by clinical scoring in all patients. In 14 patients, skin thickness was also determined by 13MHz ultrasound examination. In all patients, medium-dose UVA1 therapy softened sclerotic plaques, and marked clinical improvement was observed in 29 of 35 (82. 85%) patients. Ultrasound measurements showed that skin thickness was significantly reduced. No side effects were observed during or after treatment. Medium-dose UVA1 phototherapy is a highly effective, safe, and well-tolerated therapeutic modality for treatment of all types of LS. A 13MHz ultrasound probe may be used for evaluating UVA1 phototherapy results.

Successful treatment of microstomia with UVA1 phototherapy in systemic sclerosis

To the Editor, The introduction of phototherapy has substantially changed the therapeutic response of localized scleroderma (LS). Systemic agents have been proposed for the treatment of LS, some with potential side effects and varying degrees of success. There is sufficient evidence in the literature to demonstrate that low dose (20 J/cm) and medium dose (50 J/cm) UVA1 phototherapy is beneficial in LS. The development of a metal halide lamp emitting high levels of UVA1 radiation (340–400 nm) was first described in 1981 (1), but the therapeutic potential for UVA1 phototherapy did not emerge until 1992 with the first successful report of treating patients for acute exacerbations of atopic dermatitis. It has now been shown to soften thickened plaques, increase skin elasticity and reduce lesional skin thickness in scleroderma (2–4). Recently (4), low-dose UVA1, mediumdose UVA1 and narrowband UVB phototherapy were compared demonstrating comparable efficacy of narrowband UVB and low-dose UVA1 but medium-dose UVA1 being more effective. In systemic sclerosis (SSc), studies of UVA1 are limited. Improvement has been documented in acrosclerosis in those patients with SSc (5). There is no documentation of treatment of other features of SSc by phototherapy in the literature. We describe a case of successful treatment of microstomia with UVA1 phototherapy in a patient with SSc. Case report

5-Methoxypsoralen plus ultraviolet (UV) A is superior to medium-dose UVA1 in the treatment of severe atopic dermatitis: a randomized crossover trial

5-Methoxypsoralen plus ultraviolet (UV) A is superior to medium-dose UVA1 in the treatment of severe atopic dermatitis: a randomized crossover trial

5-Methoxypsoralen plus ultraviolet (UV) A is superior to medium-dose UVA1 in the treatment of severe atopic dermatitis: a randomized crossover trial

Ultraviolet (UV) A1 and psoralen plus UVA (PUVA) are effective treatment options for severe atopic dermatitis (AD); however, their relative efficacy has not yet been determined in a head-to-head study. To compare UVA1 and oral 5-methoxypsoralen (5-MOP) plus UVA with respect to efficacy, tolerability and duration of response in patients with severe generalized AD. Forty patients were included in this randomized observer-blinded crossover trial. The patients received either 15 exposures to medium-dose UVA1 as the first treatment and, in cases of relapse, another 15 exposures to 5-MOP plus UVA as the second treatment, or vice versa. All patients were followed until 12 months after discontinuation of the last treatment. The SCORAD score was determined by a blinded investigator at baseline, after 10 and 15 treatments each and during the follow-up period. In addition, all adverse events were recorded during the whole study period. Twenty-three patients completed the crossover treatment. Both phototherapies resulted in clinical improvement; however, PUVA reduced the baseline SCORAD score to a significantly greater extent than UVA1 (mean +/- SD 54.3 +/- 25.7% vs. 37.7 +/- 22.8%; P = 0.041). The median length of remission was 4 weeks (interquartile range 4-12) after UVA1 and 12 weeks (interquartile range 4-26) after PUVA therapy (P = 0.012). PUVA provides a better short- and long-term response than medium-dose UVA1 in patients with severe AD.

Successful ultraviolet A1 phototherapy in the treatment of localized scleroderma: a retrospective and prospective study

Ultraviolet (UV) A1 phototherapy is an effective anti-inflammatory treatment modality that influences fibroblast functions. To document the effects of UVA1 treatment in patients with localized scleroderma (LS) in a retrospective study (at least 6 months after UVA1 treatment) and in a prospective study before and immediately after medium-dose UVA1 irradiation. In total, 30 patients (retrospective study n = 17, prospective study n = 13) with LS receiving UVA1 phototherapy five times weekly (for 3-6 weeks) were investigated. Improvement was documented using standardized questionnaires and clinical evaluation (using modified Rodnan skin score, Cutometer and 7.5-MHz ultrasound measurements). Levels of collagen I and collagen III metabolites were measured in serum and urine. In the retrospective study, medium-dose UVA1 phototherapy had been performed 6 months-3 years earlier (cumulative dose 750-1400 J cm(-2); mean + or - SD number of irradiations 19.3 + or - 3.8). Fourteen of 17 patients (82%) reported an improvement in symptoms following UVA1 therapy. In the prospective study, skin elasticity increased in 77% of the patients following medium-dose UVA1 phototherapy (cumulative dose 750-1250 J cm(-2); mean + or - SD number of irradiations 20.8 + or - 4.0). 7.5-MHz ultrasound measurements showed a mean reduction of lesional skin thickness of 13% compared with skin thickness before UVA1 phototherapy. The ratio of deoxypyridinoline to creatinine was significantly elevated in about two-thirds of the patients. This open study showed a positive short- and long-term efficacy of UVA1 phototherapy in patients with LS, with a reduction in sclerotic plaques, an increase in skin elasticity and a reduction of lesional skin thickness. UVA1 phototherapy had a significant effect on collagen metabolism. UVA1 phototherapy can be regarded as a safe treatment modality for patients with LS.

Medium-dose is more effective than low-dose ultraviolet A1 phototherapy for localized scleroderma as shown by 20-MHz ultrasound assessment

Recent studies suggest that ultraviolet (UV) A1 phototherapy is an effective treatment for localized scleroderma (LS); however, the optimum UVA1 dose remains to be determined. We sought to compare the immediate and long-term efficacy of low- versus medium-dose UVA1 phototherapy for plaque-type LS. Three comparable plaques in 16 patients were treated with 20 J/cm2 UVA1, 70 J/cm2 UVA1, or no irradiation. In total, 30 treatments were given. Skin thickness was determined by high-frequency ultrasound examination and clinical scoring. Assessments were done at baseline, immediately after treatment, and 3, 6, and 12 months thereafter. Ultrasound measurement showed a significantly greater reduction of skin thickness with 70 J/cm2 than with 20 J/cm2 at all time points of the study except immediately after UVA1 treatment. The clinical score of the irradiated plaques also decreased substantially but failed to detect a significant difference between the two dose regimens. Our results only pertain to plaque-type LS and are limited by a small sample size. Medium-dose provides for better long-term results than low-dose UVA1 in LS as shown by ultrasound assessment. With clinical scoring, no significant difference between the two UVA1 dose regimens was detected, indicating that ultrasound measurement is a more sensitive method for quantifying treatment-induced skin changes in patients with LS.

Experimental study on the effect of different doses of UVA1 irradiation in the treatment of mouse model of scleroderma.

Objective To compare the changes of skin thickness and collagen content in mouse models of scleroderma after irradiated with different doses of UVA1, so as to seek the suitablc irradiation dose in the treatment for scleroderma. Methods Sixty mice were randomly and equally divided into 6 groups: blank control group (no injection and no irradiation), model control group (injected only and killed 2 days after the last injection), high-dose (HD) UVA1 group (injected with bleomycin and irradiated with UVA1 of 100 J/cm2), medium-dose (MD) UVA1 group (injected with bleomycin and irradiated with UVA1 of 60 J/cm2), low-dose (LD) UVA1 group (injected with bleomycin and irradiated with UVA1 of 20 J/cm2), and negative control group (injected only and killed until the end of irradiation). Experimental mouse models of scleroderma were established by subcutaneous injection of 100 μL bleomycin (BLM) at 400 μg/mL into the back of BALB/c mouse once a day for 4 weeks. Phototherapy was performed 3 times weekly for 10 weeks. Thereafter, skin specimens were obtained from the injected or irradiated back of mice, and subjected to an observation on pathological changes of skin tissue and thickness, as well as the measurement of collagen content. Results There was statistical differences between blank control group and model control group in both the skin thickness (t= 4.945, P<0.001) and collagen content (t=3.712, P<0.01). UVAI phototherapy improved the skin sclerosis and reduced the thickness in mouse models, but significant effect was only observed with HD-UVA1 in both the parameters(both P<0.05). There was significant difference among the 3 groups receiving phototherapy in the changes of skin thickness (F=14.853, P<0.01) and collagen content (F= 6.317, P<0.01), and HD-UVAI was significantly more effective than MD-UVA1 and LD-UVA1. Conclusion High-dose UVAI irradiation could significantly reduce the changes in skin thickness and col- lagen content in mouse model of sclerosis induced by bleomycin,which may be related to its inhibition on collagen fiber proliferation and decrease in collagen content. Key words: Sclerodelma, limited; Ultraviolet ray; Disease models, animal