Eradication of skin microbiota restores cytokine production and release in polymorphic light eruption.

Polymorphic light eruption (PLE) has been mechanistically linked to cytokine abnormalities. Emerging preclinical evidence posits the skin microbiome as a critical modulator of ultraviolet (UV)-induced cytokine expression, thereby influencing subsequent immune responses. This intricate relationship remains underexplored in the context of PLE. Hence, we investigated the differential responses between disinfected and non-disinfected skin following both single and repetitive exposures to solar-simulated UV radiation in patients with PLE. An experimental, half-body pilot study was conducted involving six PLE patients and 15 healthy controls. Participants' skin was exposed to single and multiple doses of solar-simulated UV radiation, both in disinfected and in non-disinfected skin areas. The co-primary outcomes were PLE score and cytokine expression in blister fluid analysed through OLINK proteomic profiling. Secondary outcomes were erythema, pigmentation, induction of apoptotic cells in vacuum-generated suction blisters, and density of infiltrate in skin biopsies of PLE patients. Among the 71 cytokines analysed, baseline expression levels of 20 specific cytokines-integral to processes such as apoptosis, inflammation, immune cell recruitment, cellular growth, and differentiation-were significantly impaired in PLE patients compared with healthy controls. Notably, skin disinfection reversed the observed cytokine imbalances following a single UV exposure at the minimal erythema dose (MED) level and exhibited even more pronounced effects after multiple UV exposures. However, no significant differences were evident in PLE score, erythema, pigmentation, or rates of apoptotic cell induction upon UV radiation. These findings provide evidence for UV-driven cytokine regulation by the skin microbiota and imply microbiome involvement in the PLE immune response.

Narrowband-ultraviolet B vs Broadband-ultraviolet B in Treatment of Chronic Pruritus: A Randomized, Single-blinded, Non-inferiority Study.

Narrowband-ultraviolet B has shown increased efficacy over broadband-ultraviolet B in pruritic skin diseases, such as psoriasis and atopic dermatitis. In patients with chronic pruritus, e.g. in end-stage renal disease, broadband-ultraviolet B is recommended, but narrowband-ultraviolet B has also shown efficacy in reducing pruritus. This randomized, single blinded, non-inferiority study investigated the effects of narrowband-ultraviolet B compared with broadband-ultraviolet B. Patients with chronic pruritus were treated with either broadband- or narrowband-UVB 3 times a week for 6 weeks and clinical response was monitored. Pruritus, sleep disturbance, and the patients' subjective overall response to treatment were evaluated by the patients on a visual analogue scale (0-10). Skin excoriations were evaluated by investigators on a 4-point scale (0-3). Both phototherapeutic modalities showed significant antipruritic activity (itch reduction 48% and 66.4%, respectively) by broadband-ultraviolet B and narrowband-ultraviolet B. Narrowband-ultraviolet B proved to be not inferior to broadband-ultraviolet B in treating pruritus in patients with chronic pruritus, assuming a 20% non-inferiority margin.

Evolution of characteristics and biologic treatment effectiveness in patients of the Austrian psoriasis registry from 2004-2022.

BACKGROUND AND OBJECTIVES: This study analyzed the extent to which the recent introduction of more effective treatments has led to an improvement in real-world psoriasis patients. PATIENTS AND METHODS: Patient characteristics and the first-year treatment effectiveness in biologic-naive patients have been analyzed since 2004 until now, irrespective of treatment switches. RESULTS: Data from 2,729 patients were eligible for this analysis. The proportion of female patients increased significantly over the years from 29.9% to 36.2% (p < 0.028), while the number of patients with psoriatic arthritis declined from 36.6% to 30.0% (p < 0.001). Moreover, the duration of psoriatic disease and PASI at the start of the treatment significantly decreased. Last observation carrief forward (LOCF) analysis indicated that PASI 90 response increased from 18.9 to 44.6% at 3 months and from 32.9 to 66.8% at 12 months after treatment started. Similary, the PASI ≤ 3 rates increased from 33.2% to 66.0% at 3 months and from 41.9% to 78.9% at 12 months after the treatment started. CONCLUSIONS: The continuous introduction of more efficient biologics has led to significant improvements in patient care and clinical outcomes. Though one out of three to five patients, depending on the endpoint selected, nowadays still does not achieve an entirely satisfactory treatment response (i.e., PASI 90 or PASI ≤ 3).

Frequency of occurrence of polymorphic light eruption in patients treated with photohardening and patients treated with phototherapy for other diseases.

BACKGROUND: Medical phototherapy can lead to the manifestation of polymorphic light eruption (PLE), though little is known about the frequency of such events. AIMS: The aim of this Austrian single center study was to retrospectively investigate over a 4-year time period the frequency of PLE in patients prone to the condition and patients with other diseases under phototherapy (mainly narrow-band and broad-band UVB). MATERIALS AND METHODS: The data for analysis were obtained from the electronic health and patient record database and patient files of the Photodermatology Unit, Department of Dermatology, Medical University of Graz, Austria. RESULTS: PLE occurred in 24.3% (18/74) of PLE patients but only 0.7% (3/421) of psoriasis patients under phototherapy (chi-square; P < 0.0001). PLE also occurred in 1.2% (3/257) of patients with atopic eczema, 0.8% (1/118) with prurigo, 3.5% (4/115, P = 0.0206) with parapsoriasis en plaques/mycosis fungoides, 7.4% (2/27, P = 0.0013) with granuloma anulare, 14.3% (1/7, P = 0.0002) with scleroderma, and 16.7% (1/6, P < 0.0001 vs. psoriasis) with pityriasis lichenoides chronica or pityriasis lichenoides eruptiva et varioliformis acuta. DISCUSSION AND CONCLUSION: These results are helpful for treatment allocation and risk estimation of PLE occurrence with regard to obtaining informed consent not only from PLE-prone patients but also from patients with other skin disorders commonly treated by phototherapy.

Unique profile of antimicrobial peptide expression in polymorphic light eruption lesions compared to healthy skin, atopic dermatitis, and psoriasis.

BACKGROUND: Polymorphic light eruption (PLE) has been attributed to type IV, most likely delayed-type hypersensitivity response (adaptive immunity) but little is known on innate immunity, especially antimicrobial peptides (AMPs) in the disease. Abnormalities in AMP expression have been linked to pathological skin conditions such as atopic dermatitis (AD) and psoriasis. METHODS: Antimicrobial peptide profiling was carried out in PLE skin samples (n,12) compared with that of healthy (n,13), atopic (n,6), and psoriatic skin (n,6). RESULTS: Compared to healthy skin, we observed increased expression of psoriasin and RNAse7 (both mostly in stratum granulosum of the epidermis), HBD-2 (in the cellular infiltrate of the dermis), and LL37 (mostly in and around blood vessels and glands) in PLE lesional skin, a similar expression profile as present in psoriatic skin and different to that of AD (with little or no expression of psoriasin, RNAse7, HBD-2, and LL37). HBD-3 was downregulated in PLE compared to its high expression in the epidermis and dermis of healthy skin, AD, and psoriasis. CONCLUSION: The unique profile of differentially expressed AMPs in PLE implies a role in the pathophysiology of the disease, possibly directly or indirectly linked to the microbiome of the skin.

Nodular Sclerodermatous Chronic Cutaneous Graft-Versus-Host Disease (GvHD): A New Clinicopathological Variant of Cutaneous Sclerodermatous GvHD Resembling Nodular/Keloidal Scleroderma.

Cutaneous chronic graft-versus-host disease (GvHD) has a broad spectrum of clinicopathological presentations, the most common ones being poikiloderma, lichen planus-like eruptions, lichen sclerosus-like lesions, morphea-like plaques, and deep sclerosis. New forms of chronic cutaneous GvHD with different clinicopathological characteristics have been described, most of them mimicking cutaneous manifestations of autoimmune diseases. We report the case of a 35-year-old man who underwent allogenic stem cell transplantation for a therapy-associated acute myeloid leukemia and developed an acute GvHD with involvement of skin and gastrointestinal tract. He subsequently presented with chronic sclerodermatous cutaneous GvHD, followed by the appearance of indurated erythematous papules and plaques located on his back, resembling the nodular/keloidal form of cutaneous scleroderma on both clinical and histopathological grounds. This peculiar clinicopathologic presentation of chronic cutaneous GvHD was never described previously.

Desired response to phototherapy vs photoaggravation in psoriasis: what makes the difference?

Psoriasis commonly responds beneficially to UV radiation from natural sunlight or artificial sources. Therapeutic mechanisms include the proapoptotic and immunomodulating effects of UV, affecting many cells and involving a variety of pro- and anti-inflammatory cytokines, downregulating the Th17/IL-23 response with simultaneous induction of regulatory immune cells. However, exposure to UV radiation in a subset of psoriasis patients leads to exacerbation of the disease. We herein shed light on the predisposing factors of photosensitive psoriasis, including genetics (such as HLA-Cw*0602 or CARD14), gender and coexisting photodermatoses such as polymorphic light eruption (PLE) in the context of potential molecular mechanisms behind therapeutic photoresponsiveness or photoaggravation. UV-induced damage/pathogen-associated molecular patterns, damage to self-coding RNA (signalling through Toll-like receptors), certain antimicrobial peptides and/or inflammasome activation may induce innate immunity, leading to psoriasis at the site of UV exposure when there is concomitant, predisposing resistance against UV-induced suppression of the adaptive immune response (like in PLE) that otherwise would act to reduce psoriasis.

Correction: Patients with polymorphic light eruption have decreased serum levels of 25-hydroxyvitamin-D(3) that increase upon 311 nm UVB photohardening.

Correction for 'Patients with polymorphic light eruption have decreased serum levels of 25-hydroxyvitamin-D(3) that increase upon 311 nm UVB photohardening' by Peter Wolf et al., Photochem. Photobiol. Sci., 2012, 11, 1831-1836.

Survival and Effectiveness of Tumour Necrosis Factor-alpha Inhibitors in the Treatment of Plaque Psoriasis under Daily Life Conditions: Report from the Psoriasis Registry Austria.

This retrospective multicentre analysis from the Psoriasis Registry Austria (PsoRA) was conducted to determine drug effectiveness and survival of anti-tumour necrosis factor alpha (anti-TNF-α) agents in patients with moderate-to-severe chronic plaque psoriasis over a 9-year period. Data on 1,019 treatment cycles with adalimumab (n = 460), etanercept (n = 501), and/or infliximab (n = 58) administered to 827 patients (272 women, 555 men) were available for analysis. Compared with etanercept, adalimumab and infliximab showed superior short-term effectiveness. Intention-to-treat-calculated median drug survivals for adalimumab (1,264 days) and etanercept (1,438 days) were similar to each other (p = 0.74), but significantly superior to that of infliximab (477 days) (p = 7.0e-07 vs. adalimumab and p=2.2e-07 vs. etanercept, respectively). Their drug survival rates at 36 months were 51.6%, 56.0%, and 22.6%, respectively. Survival rates correlated significantly with effectiveness for adalimumab and etanercept, but not for infliximab.

Photohardening of polymorphic light eruption patients decreases baseline epidermal Langerhans cell density while increasing mast cell numbers in the papillary dermis.

The pathogenesis of polymorphic light eruption (PLE) has been linked to a lack of UV-induced immune suppression. To determine the role of Langerhans cells (LC), mast cells and regulatory T cells, biopsies from PLE patients were taken from exposed sites in spring before and after photohardening with 311 nm or PUVA as well as again in summer. Skin sections were assessed for the presence of Langerin/CD1a+ LC and CD3+, CD4+, CD25+ or FoxP3+ T cells and mast cells. Photohardening transiently decreased the density of epidermal LC and significantly increased a low baseline mast cell density in the papillary dermis of PLE patients. Baseline T cell numbers in the skin were low, and there was no difference in PLE patients among any time point. This suggests that LC suppression together with recruitment of mast cells into photohardened skin may be a key cellular event underlying the mechanism by which phototherapy protects from PLE.

Comedonal graft-vs-host disease: a distinct clinical expression of a lichenoid follicular GVHD.

We report two cases of chronic follicular graft-vs-host disease (GVHD) that resemble closed and open acne-like comedones. We propose the term 'comedonal GVHD' for this variant. A 47-year-old man presented with multiple 2-4-mm acne-like follicular papules in facial areas on day 82 status post bone marrow transplantation. A biopsy showed follicular infundibular dilation with keratotic plugs, hypergranulosis and vacuolar alteration (hydropic degeneration) of the basal layer, with dyskeratotic (apoptotic) keratinocytes, scattered lymphocytes and vascular ectasia of the superficial dermal plexus. We diagnosed chronic follicular lichenoid GVHD. The second patient was a 53-year-old female. On day 420 after transplantation, she presented with generalized dark to grayish, confluent, indurated lesions with confluent papules and unevenly distributed comedo-like lesions. Skin biopsy showed sclerotic dermis and also dilated follicular infundibula with keratotic plugging, hypergranulosis and vacuolar alteration (hydropic degeneration) of the basal layer of the epidermis. We established the diagnosis of chronic sclerodermoid GVHD with follicular lichenoid involvement. The presence of open and closed comedones on the trunk and facial region of an adult raises several differential diagnosis but in our patients, histopathologic study demonstrated typical features of GVHD, which led to this diagnoses despite the peculiar clinical findings.

Mast cells express IL17A, IL17F and RORC, are activated and persist with IL-17 production in resolved skin of patients with chronic plaque-type psoriasis.

Little is known about IL-17 expression in psoriasis and the actual cellular source of IL-17 remains incompletely defined. We show that high numbers of IL-17 + mast cells persisted in resolved lesions after treatment (anti-IL-17A, anti-IL-23, UVB or topical dithranol) and correlated inversely with the time span in remission. IL-17 + mast cells were found in T cell-rich areas and often close to resident memory T cells (Trm) in active psoriasis and resolved lesional skin. Digital cytometry by deconvolution of RNA-seq data showed that activated mast cells were increased in psoriatic skin, while resting mast cells were almost absent and both returned to normal levels after treatment. When primary human skin mast cells were stimulated with T cell cytokines (TNFα, IL-22 and IFNγ), they responded by releasing more IL-17A, as measured by ELISA. In situ mRNA detection using padlock probes specific for transcript variants of IL17A, IL17F, and RORC (encoding the Th17 transcription factor RORγt) revealed positive mRNA signals for IL17A, IL17F, and RORCin tryptase + cells, demonstrating that mast cells have the transcriptional machinery to actively produce IL-17. Mast cells thus belong to the center of the IL-23/IL-17 axis and high numbers of IL-17 + mast cells predict an earlier disease recurrence.

Phototherapeutic hardening modulates systemic cytokine levels in patients with polymorphic light eruption.

The etiopathogenesis of polymorphic light eruption (PLE) has been linked to impaired UV-immunosuppression, Langerhans cell (LC) retention, and an absence of neutrophil infiltration into UV-exposed PLE skin. We have previously shown that photohardening restores the impaired neutrophil responsiveness to the chemoattractants leucotriene B4 and formyl-methionyl-leucyl-phenylalanin in PLE patients. The aim of this study was to investigate whether photohardening modulates baseline chemokine and cytokine levels which would alter chemoresponsiveness and hence immune function in PLE patients. Sixteen PLE patients received photohardening therapy for 4-9 weeks by 311 nm UVB. Plasma samples were taken both before and within 48 h of the penultimate phototherapeutic exposure. Plasma from these 16 patients, 8 non-irradiated PLE patients, and 14 control subjects was analyzed for IL-1ß, CXCL8 (IL-8), IL-10, IL-17, TNF, CCL2 (MCP-1), CCL5 (RANTES), CCL11 (eotaxin), and CCL22 (MDC). These cytokines and chemokines were measured in early spring (March to April) and again in late spring (April to June). PLE patients had a significantly elevated level of CCL11 (p = 0.003) and IL-1ß (p = 0.002) in early spring (before phototherapy). In late spring, after phototherapy, PLE patients had significantly elevated CCL2 (p = 0.002) and TNF (p = 0.002) but a trend for lowered plasma levels of CXCL8 (p = 0.021). When comparing the cytokine shifts from early to late spring, while healthy controls and non-UV-irradiated PLE patients showed an increase, PLE patients undergoing photohardening exhibited a trend for decrease in IL-1ß (p = 0.012). Taken together, our results indicate that photohardening may alter the complex cytokine milieu in PLE, in particular via IL-1ß, helping to normalise the pathophysiologic response to subsequent UV exposure.

Patients with polymorphic light eruption have decreased serum levels of 25-hydroxyvitamin-D3 that increase upon 311 nm UVB photohardening.

BACKGROUND: Polymorphic light eruption (PLE) is a very common condition whose pathogenesis may involve immunological abnormalities. Vitamin D sufficiency is thought to be important for normal immune function. OBJECTIVE: To determine whether PLE patients are vitamin D deficient and to study how photohardening with 311 nm UVB affects the vitamin D status of PLE patients. METHODS: The vitamin D status of 23 PLE patients (21 females and 2 males; age range, 18-55 years) was analysed at four different time points (early spring, late spring, summer, and winter) by measuring 25-hydroxyvitamin-D(3) (25(OH)D) serum levels through a standardised immunoassay. Fifteen of those patients received 311 nm UVB in early spring for prevention of PLE symptoms. 25(OH)D levels of the PLE patients were compared to that of 23 sex-, age-, and body-mass-index post hoc-matched control subjects. RESULTS: PLE patients had low levels of 25(OH)D throughout the year compared to that of the control subjects. At baseline in early spring, the mean ± SD 25(OH)D level was 14.9 ± 3.0 ng ml(-1) in the PLE patients that would later receive 311 nm UVB and 14.4 ± 2.4 ng ml(-1) in the patients not receiving 311 nm UVB. Successful prophylactic treatment with 311 nm UVB significantly increased 25(OH)D levels to a mean of 21.0 ± 3.4 ng ml(-1) (p < 0.001; ANOVA, Tukey's test). Heading into summer, the 25(OH)D levels in treated patients decreased again, reaching their lowest levels in winter. In contrast, the 25(OH)D levels of untreated PLE patients stayed in the low range in early and late spring but increased by trend towards summer, reaching similar levels to that of the PLE patients who had received 311 nm UVB (17.1 ± 2.3 vs. 17.3 ± 6.0 ng ml(-1)). Like the treated PLE patients, 25(OH)D levels of untreated patients significantly decreased in winter to comparable levels (12.2 ± 1.9 vs. 13.8 ± 1.8 ng ml(-1)). Taken together, the 25(OH)D levels of PLE patients were significantly lower at all time points than that observed in the matched control population (34.4 ± 12.5 ng ml(-1)) (p < 0.000003). CONCLUSIONS: PLE patients have low 25(OH)D serum levels. 311 nm UVB phototherapy that prevented PLE symptoms increased those levels. Thus, we speculate that boosting levels of vitamin D may be important in ameliorating PLE.

Accumulation of Cytotoxic Skin Resident Memory T Cells and Increased Expression of IL-15 in Lesional Skin of Polymorphic Light Eruption.

Patients with polymorphic light eruption (PLE) develop lesions upon the first exposure to sun in spring/summer, but lesions usually subside during season due to the natural (or medical) photohardening. However, these lesions tend to reappear the following year and continue to do so in most patients, suggesting the presence of a disease memory. To study the potential role of skin resident memory T cells (Trm), we investigated the functional phenotype of Trm and the expression of IL-15 in PLE. IL-15 is known to drive Trm proliferation and survival. Multiplex immunofluorescence was used to quantify the expression of CD3, CD4, CD8, CD69, CD103, CD49a, CD11b, CD11c, CD68, granzyme B (GzmB), interferon-gamma (IFN-γ), and IL-15 in formalin-fixed, paraffin-embedded lesional skin samples from PLE patients and healthy skin from control subjects. Unlike the constitutive T cell population in healthy skin, a massive infiltration of T cells in the dermis and epidermis was observed in PLE, and the majority of these belonged to CD8+ T cells which express Trm markers (CD69, CD103, CD49a) and produced cytotoxic effector molecules GzmB and IFN-γ. Higher numbers of CD3+ T cells and CD11b+CD68+ macrophages produced IL-15 in the dermis as compared to healthy skin. The dominant accumulation of cytotoxic Trm cells and increased expression of IL-15 in lesional skin of PLE patients strongly indicates the potential role of skin Trm cells in the disease manifestation and recurrence.

Photohardening restores the impaired neutrophil responsiveness to chemoattractants leukotriene B4 and formyl-methionyl-leucyl-phenylalanin in patients with polymorphic light eruption.

A failure to induce immune suppression after UV exposure has been implicated in the pathogenesis of polymorphic light eruption (PLE). This immunological resistance has been linked to an impaired neutrophil infiltration into the skin following UV exposure. Therapeutic photohardening can restore this abnormal neutrophil infiltration in PLE skin and is thought to be responsible for the prophylactic efficacy. The aim of this study was to elucidate the pathogenic mechanism of the described neutrophil deficiency in PLE. Peripheral blood neutrophil responses to the chemoattractants leukotriene B4 (LTB(4)) and formyl-methionyl-leucyl-phenylalanin (fMLP) were investigated in vitro. Samples from 10 patients with PLE before and after 6 weeks of photohardening therapy were assessed. Flow cytometry was used to measure the changes associated with neutrophil activation. We found a significantly reduced neutrophil responsiveness to LTB(4) and fMLP in PLE patients, which was restored to normal levels after phototherapy. Indeed, PLE neutrophil responsiveness to these two chemoattractants after (but not before) phototherapy was similar to that of age- and sex-matched healthy control subjects. This indicates that an abnormal chemotactic potential to neutrophils is a crucial factor in the pathogenesis of PLE. Normalization following photohardening may therefore account for the therapeutic efficacy by restoring UV-induced neutrophil skin infiltration. Our results reveal a completely novel pathogenic mechanism involved in PLE and offer unique targets for therapy.

Topical liposomal DNA-repair enzymes in polymorphic light eruption.

Polymorphic light eruption (PLE) is a very frequent photodermatosis in Europe whose pathogenesis may involve resistance to UV-induced immune suppression and simultaneous immune reactions against skin photoneoantigens. We performed a randomized, double-blind, placebo-controlled intra-individual half-body trial to investigate the protective effect of an after-sun (AS) lotion containing DNA-repair enzymes (photolyase from Anacystis nidulans and Micrococcus luteus extract with endonuclease activity). Fourteen PLE patients were exposed to suberythemal doses of solar-simulated UV radiation on 4 consecutive days at 4 symmetrically located PLE-prone test fields per patient. The test fields were treated with (i) active AS lotion or (ii) a placebo lotion immediately after each UV exposure, or (iii) an SPF30 sunscreen before UV exposure or left untreated. All test fields were exposed to photoactivating blue light 1 h after each UV exposure. As shown by a newly established specific PLE test score (AA + SI + 0.4P [range, 0-12], where AA is affected area score [range, 0-4], SI is skin infiltration score [range, 0-4], and P is pruritus score on a visual analogue scale [range, 0-10]), PLE symptoms were significantly fewer on test sites treated with active AS lotion than on untreated (P = 0.00049) or placebo-treated test sites (P = 0.024). At 144 h after first UV exposure (the time point of maximal PLE symptoms), the mean test scores for untreated, active AS lotion-treated, and placebo-treated test fields were 4.39, 1.73 (61% reduction; 95% confidence interval (CI), 36% to 85%), and 3.20 (27% reduction; 95% CI, 3% to 51%), respectively. Pretreatment with SPF30 sunscreen completely prevented PLE symptoms in all patients. The present results indicate that DNA damage may trigger PLE and that the application of topical liposomes containing DNA repair enzymes to increase DNA repair may effectively prevent PLE.

311 nm ultraviolet B-accelerated response of psoriatic lesions in adalimumab-treated patients.

BACKGROUND: Treatment with the tumor necrosis factor-alpha antibody adalimumab for 12-16 weeks produces a satisfactory response [i.e., 75% reduction in psoriasis area and severity index (PASI)] in a majority (70-80%) of patients with psoriasis. We asked whether 311 nm ultraviolet B (UVB) can improve therapeutic response of psoriatic lesions to adalimumab. METHODS: Four patients (age range, 49-67 years) with moderate to severe plaque-type psoriasis were treated with standard dosage of adalimumab. During adalimumab therapy, a randomly selected body half (left or right, excluding the head) was irradiated with 311 nm UVB three times weekly for 6 weeks. Treatment response was monitored weekly in terms of half-body PASI. RESULTS: 311 nm UVB significantly accelerated the therapeutic response during adalimumab treatment. At the start of 311 nm UVB therapy, the mean PASI was 14.8. After 6 weeks of 311 nm UVB therapy, the mean PASI was 2.0 on UV-irradiated body halves and 6.9 on non-irradiated body halves (difference, 4.9; 95% confidence interval, 0.4-9.4; P=0.041; 2-tailed paired t-test). This corresponded to an overall mean PASI reduction from baseline (i.e., adalimumab start) of 86% on UV-irradiated body halves vs. 53% on non-irradiated body halves. CONCLUSION: 311 nm UVB may accelerate and improve the clearance of psoriatic lesions in adalimumab-treated patients.

Long-Term Course of Polymorphic Light Eruption: A Registry Analysis.

Background: Little is known about the long-term course of polymorphic light eruption (PLE). Objective: To predict disease course, a questionnaire was sent to patients whose PLE had been diagnosed between March 1990 and December 2018 and documented in the Austrian Cooperative Registry for Photodermatoses. Methods: In January 2019, 205 PLE patients were contacted by mail and asked to complete a questionnaire on their disease course, including whether the skin's sun sensitivity had normalized (i.e., PLE symptoms had disappeared), improved, stayed the same, or worsened over time. Patients who reported normalization of sun sensitivity were asked to report when it had occurred. Results: Ninety-seven patients (79 females, 18 males) returned a completed questionnaire. The mean (range) duration of follow-up from PLE onset was 29.6 (17-54) years for females and 29.4 (16-47) years for males. The disease disappeared in 32 (41%) females after 17.4 (2-41) years and in 4 (24%) males after 11.8 (5-26) years. Twenty-nine (37%) females and 6 (35%) males reported improvement of symptoms over time; 15 females (19%) and 7 males (41%) reported no change; and 3 females (4%) and no males reported worsening of symptoms. Kaplan-Meier analysis revealed that after 20 years 74% (95%CI, 64-82%) of patients still suffered from PLE. PLE lesion persistence (>1 week) tended to predict a prolonged course of PLE. Conclusions: PLE usually takes a long-term course over many years though in most patients its symptoms improve or disappear over time. How improvement relates to the pathophysiology of the disease remains to be determined.