Low-dose UVA1 phototherapy for scleroderma: what benefit can we expect?

Efficacy of ultraviolet A1 phototherapy for inflammatory, sclerotic and neoplastic dermatological diseases: A 10-year tertiary referral center experience

BACKGROUND

Ultraviolet (UV) A1 phototherapy is considered a beneficial treatment for various inflammatory, sclerotic, malignant, and other skin conditions. However, the available data regarding its efficacy for different indications, the potential side effects, and the recommended treatment protocols are sparse.

OBJECTIVES

To assess the efficacy of UVA1 phototherapy and identify correlation between different indications and treatment protocols to response rates.

METHODS

We performed a retrospective study of a cohort of 335 patients treated with UVA1 phototherapy at the Department of Dermatology at Hadassah Medical Center, Jerusalem, Israel, between 2008 and 2018.

RESULTS

The study population included 163 patients with inflammatory diseases (mainly atopic dermatitis and other types of eczema), 67 patients with sclerotic diseases (morphea and graft versus host disease), nine patients with neoplastic diseases (cutaneous T cell lymphoma), and 188 patients with other cutaneous disorders. Response rates ranged between 85% and 89% across indications, without differences in response rates among the indication groups (p = .941). In a multivariant logistic regression model, increased number of treatments and higher maximal dosages were associated with response to treatment (p < .001). Using ROC analysis, a cut-off of 8 UVA1 phototherapy treatments was chosen as predictive for beneficial response (86.4% sensitivity, 78% specificity). A cut-off of 40 J/cm² was chosen as an optimal maximal dosage for differentiating between responders and non-responders (51.1% sensitivity, 83.1% specificity).

CONCLUSIONS

UVA1 phototherapy is an effective treatment for a variety of skin conditions. In most patients, at least eight treatments of a medium-high dosage are required for clinical response.

Utility of phototherapy in patients with systemic sclerosis: systematic review

Phototherapy is a recommended treatment regimen for different scleroderma spectrum disorders, but so far it has been included neither by European nor by worldwide experts committee in recommendations for the treatment of systemic sclerosis (SSc). The aim of the study was to revisit the utility of dermatological phototherapy in patients with SSc. PubMed using medical subject headings was searched to identify studies evaluating response to dermatological phototherapy in SSc patients. Both UVA1 (340-400 nm) and PUVA (psoralen plus UVA) treatments were found to reduce skin thickening and increase skin elasticity, therefore allowing for the improvement of joint tension mobility, especially in hands. At least several papers showed efficacy of phototherapy in patients who remained non-responsive to previous immunosuppressive therapies. The most probable mechanisms of action of phototherapy in SSc include inhibition of T-cells and prevention from dermal fibrosis. Although most data on the efficacy of phototherapy come from small experimental studies and case reports, phototherapy based on UVA of wavelength manifests relatively mild spectrum of side effects and this should be considered as a treatment option for SSc with dominant cutaneous involvement. This article is protected by copyright. All rights reserved.

Utilizing UVA-1 Phototherapy

There is a long history of utilization of phototherapy for treatment of skin conditions. Because of its longer wavelength, UVA1 phototherapy is able to penetrate into the dermis and subcutis. This depth of penetration, combined with its unique immunomodulating properties, makes UVA1 an effective treatment modality for many immune-mediated skin diseases. In some cases, it performs better than other types of phototherapy.

Ultraviolet A1 Phototherapy for Fibrosing Conditions

In this article we describe efficacy and safety aspects of ultraviolet A1 (UV-A1) phototherapy in fibrosing conditions. UV-A1 is a specific phototherapeutic modality that is defined by a selective spectral range (340–400 nm). UV-A1 includes distinct modes of action qualifying this method for therapy of a variety of conditions, in particular fibrosing skin diseases. Concerning efficacy of UV-A1 phototherapy in fibrosing conditions, the best evidence obtained from randomized controlled trials exists for localized scleroderma. Moreover, fibrosing disorders such as lichen sclerosus and graft-vs.-host disease can be treated successfully by means of UV- A1. Regarding the optimal dosage regimen medium-dose UV-A1 seems to be linked to the best benefit/risk ratio. Possible acute adverse events of UV-A1 phototherapy include erythema and provocation of photodermatoses. Skin ageing and skin cancer formation belong to the chronic adverse events that may occur after long-term UV-A1 phototherapy.

Pruritus in Autoimmune Connective Tissue Diseases

Pruritus in autoimmune connective tissue diseases is a common symptom that can be severe and affect the quality of life of patients. It can be related to disease activity and severity or occur independent of the disease. Appropriate therapy to control the itch depends on the etiology, and it is therefore essential to first work-up these patients for the underlying trigger.

S1-Leitlinie zur UV-Phototherapie und Photochemotherapie

Die heilsame Wirkung des Sonnenlichts war teilweise schon im Altertum bekannt und fand in der zweiten Hälfte des 19. Jahrhunderts wieder zunehmend Beachtung. Den Beginn der modernen Phototherapien markiert die Entwicklung einer Apparatur zur ultravioletten Bestrahlung der Hauttuberkulose durch Finnsen zu Beginn des zwanzigsten Jahrhunderts. Zur Therapie von Hauterkrankungen finden beinahe ausschließlich die spektralen Bereiche unterhalb des sichtbaren Lichtes (ultraviolett) Anwendung. Seit den 1970er Jahren stehen zunehmend leistungsfähige künstliche Strahlenquellen bereit für die Therapie mit UVB, UVA und die Kombination von UVA mit Photosensibilisatoren (Photochemotherapie). Hohe strukturelle und prozedurale Qualitätsstandards sind unabdingbare Voraussetzung für die Durchführung einer gleichermaßen wirkungsvollen wie auch sicheren Phototherapie. Die Leitlinie formuliert den aktuellen Konsens führender Experten auf dem Gebiet der Phototherapie in Bezug auf die Indikationen für die jeweiligen Therapieverfahren, deren Gegenanzeigen und Nebenwirkungen und insbesondere für die Wahl der korrekten Dosis zu Beginn und im Verlauf einer Therapie sowie das Management von Nebenwirkungen.

Phototherapy in systemic sclerosis: Review

Systemic scleroderma-also known as systemic sclerosis (SSc)-is a chronic systemic connective tissue disease characterized by collagen deposition in cutaneous and internal organs, leading to skin sclerosis and multiple organ fibrosis. The pathogenesis is complex and remains poorly understood. Treatment is based on organ involvement and requires a multidisciplinary approach. Skin sclerosis can cause disability, leading to decreasing quality of life. Various systemic antifibrotic therapies have been used; however, most have unsatisfactory results. Recently, phototherapy and in particular ultraviolet A (UVA) has been used to treat skin sclerosis in SSc patients with satisfactory results. The main mechanisms include lymphocyte apoptosis, cytokine alteration, inhibition of collagen synthesis and increased collagenase production, and neovascularization, leading to the breakdown of collagen fibrils resulting in skin softening or even healing digital ulcers. Most studies reported that psoralen plus UVA (PUVA) and UVA1 phototherapy improved clinical outcomes vis-à-vis skin sclerosis, joint mobility, ulcers, and histopathology. PUVA and UVA1 phototherapy therefore have potential as an alternative or adjunctive therapy for patients with SSc.

Phototherapy in Scleroderma

Systemic and localized scleroderma are difficult to manage diseases with no accepted gold standard of therapy to date. Phototherapeutic modalities for scleroderma show promise. A PubMed search of information on phototherapy for scleroderma was conducted. The information was classified into effects on pathogenesis and clinical outcomes. Studies on photopheresis were excluded. There were no randomized, double-blind, placebo-controlled studies, and only three controlled studies. The vast majority of identified studies evaluated ultraviolet A1 (UVA1) phototherapy. More rigorous studies are needed to evaluate phototherapy in the treatment of scleroderma. Based on the limited studies available, 20-50 J/cm² of UVA1 therapy 3-4 times a week for 30 treatments is recommended.

Fractional carbon dioxide laser versus low-dose UVA-1 phototherapy for treatment of localized scleroderma: a clinical and immunohistochemical randomized controlled study

Morphea is a rare fibrosing skin disorder that occurs as a result of abnormal homogenized collagen synthesis. Fractional ablative laser resurfacing has been used effectively in scar treatment via abnormal collagen degradation and induction of healthy collagen synthesis. Therefore, fractional ablative laser can provide an effective modality in treatment of morphea. The study aimed at evaluating the efficacy of fractional carbon dioxide laser as a new modality for the treatment of localized scleroderma and to compare its results with the well-established method of UVA-1 phototherapy. Seventeen patients with plaque and linear morphea were included in this parallel intra-individual comparative randomized controlled clinical trial. Each with two comparable morphea lesions that were randomly assigned to either 30 sessions of low-dose (30 J/cm²) UVA-1 phototherapy (340-400 nm) or 3 sessions of fractional CO₂ laser (10,600 nm-power 25 W). The response to therapy was then evaluated clinically and histopathologically via validated scoring systems. Immunohistochemical analysis of TGF-ß1 and MMP1 was done. Patient satisfaction was also assessed. Wilcoxon signed rank test for paired (matched) samples and Spearman rank correlation equation were used as indicated. Comparing the two groups, there was an obvious improvement with fractional CO₂ laser that was superior to that of low-dose UVA-1 phototherapy. Statistically, there was a significant difference in the clinical scores (p = 0.001), collagen homogenization scores (p = 0.012), and patient satisfaction scores (p = 0.001). In conclusion, fractional carbon dioxide laser is a promising treatment modality for cases of localized morphea, with proved efficacy of this treatment on clinical and histopathological levels.

Dermal damage promoted by repeated low-level UV-A1 exposure despite tanning response in human skin

IMPORTANCE

Solar UV irradiation causes photoaging, characterized by fragmentation and reduced production of type I collagen fibrils that provide strength to skin. Exposure to UV-B irradiation (280-320 nm) causes these changes by inducing matrix metalloproteinase 1 and suppressing type I collagen synthesis. The role of UV-A irradiation (320-400 nm) in promoting similar molecular alterations is less clear yet important to consider because it is 10 to 100 times more abundant in natural sunlight than UV-B irradiation and penetrates deeper into the dermis than UV-B irradiation. Most (approximately 75%) of solar UV-A irradiation is composed of UV-A1 irradiation (340-400 nm), which is also the primary component of tanning beds.

OBJECTIVE

To evaluate the effects of low levels of UV-A1 irradiation, as might be encountered in daily life, on expression of matrix metalloproteinase 1 and type I procollagen (the precursor of type I collagen).

DESIGN, SETTING, AND PARTICIPANTS

In vivo biochemical analyses were conducted after UV-A1 irradiation of normal human skin at an academic referral center. Participants included 22 healthy individuals without skin disease.

MAIN OUTCOMES AND MEASURES

Skin pigmentation was measured by a color meter (chromometer) under the L* variable (luminescence), which ranges from 0 (black) to 100 (white). Gene expression in skin samples was assessed by real-time polymerase chain reaction.

RESULTS

Lightly pigmented human skin (L* >65) was exposed up to 4 times (1 exposure/d) to UV-A1 irradiation at a low dose (20 J/cm2), mimicking UV-A levels from strong sun exposure lasting approximately 2 hours. A single exposure to low-dose UV-A1 irradiation darkened skin slightly and did not alter matrix metalloproteinase 1 or type I procollagen gene expression. With repeated low-dose UV-A1 irradiation, skin darkened incrementally with each exposure. Despite this darkening, 2 or more exposures to low-dose UV-A1 irradiation significantly induced matrix metalloproteinase 1 gene expression, which increased progressively with successive exposures. Repeated UV-A1 exposures did not suppress type I procollagen expression.

CONCLUSIONS AND RELEVANCE

A limited number of low-dose UV-A1 exposures, as commonly experienced in daily life, potentially promotes photoaging by affecting breakdown, rather than synthesis, of collagen. Progressive skin darkening in response to repeated low-dose UV-A1 exposures in lightly pigmented individuals does not prevent UV-A1-induced collagenolytic changes. Therefore, for optimal protection against skin damage, sunscreen formulations should filter all UV wavelengths, including UV-A1 irradiation.

Updates on morphea: role of vascular injury and advances in treatment

Morphea and systemic sclerosis are fibrosing disorders of the skin that share common inflammatory and immunologic pathways that are responsible for the vascular changes, increased collagen production, and extracellular matrix proliferation seen in both conditions. Recent advances in molecular biology techniques have furthered our knowledge of the potential underlying pathogenic mechanisms and offer new and provocative areas of research for novel diagnostic and therapeutic interventions. This review focuses on the role of vascular injury in the development of morphea, the use of ultrasonography as a diagnostic modality, and well-established and newly proposed treatments.

UVA-1 therapy of localized scleroderma and other diseases accompanied by skin sclerosis

The study results confirm the efficacy of the UVA-1 therapy for patients with localized scleroderma, extragenital lichen sclerosus et atrophicus, sclerodermatous chronic graft-versus-host disease and scleredema adultorum. The therapy has an anti-inflammatory and anti^m^ action, arrests progression and reduces the activity of the disease process, and has a good efficacy and safety profile.

UVA-induced protection of skin through the induction of heme oxygenase-1

UVA (320-400 nm) and UVB (290-320 nm) are the major components of solar UV irradiation, which is associated with various pathological conditions. UVB causes direct damage to DNA of epidermal cells and is mainly responsible for erythema, immunosuppression, photoaging, and skin cancer. UVA has oxidizing properties that can cause damage or enhance UVB damaging effects on skin. On the other hand, UVA can also lead to high levels of heme oxygenase-1 (HO-1) expression of cells that can provide an antioxidant effect on skin as well as anti-inflammatory properties in mammals and rodents. Therefore, this review focuses on the potential protection of UVA wavebands for the skin immune response, instead of mechanisms that underlie UVA-induced damage. Also, the role of HO-1 in UVA-mediated protection against UVB-induced immunosuppression in skin will be summarized. Thus, this review facilitates further understanding of potential beneficial mechanisms of UVA irradiation, and using the longer UVA (UVA1, 340-400 nm) in combination with HO-1 for phototherapy and skin protection against sunlight exposure.