Erythemal and therapeutic response of psoriasis to PUVA using high-dose UVA

In PUVA treatment of psoriasis, clinical observation suggests that uninvolved skin is more susceptible to PUVA erythema than lesions of psoriasis. If this is the case, then the efficacy of PUVA treatment might be increased by using localized high-dose UVA restricted to lesional skin. We have therefore studied the erythemal and therapeutic response of psoriasis to PUVA using high-dose UVA and, for comparison, the erythemal response to UVB. In 14 patients, an area of psoriasis and adjacent uninvolved skin were exposed to a series of UVA doses (350 ± 30 nm, 1–16 J/cm²), using an irradiation monochromator. Six other patients were similarly phototested with a series of UVB doses (300 ± 5 nm, 20–112 mJ/cm²) to both uninvolved and lesional skin. Erythema was judged visually at 72 h for psoralen–UVA, and at 24 h for UVB, and measured using a scanning laser–Doppler velocimeter. In 10 patients, PUVA therapy using high-dose UVA was subsequently given to lesional skin (8–16 J/cm² twice weekly) in addition to conventional whole-body PUVA. For psoralen–UVA, the minimal phototoxic dose within psoriasis was increased by a factor of 4 compared with non-lesional skin (P < 0.01, Wilcoxon signed-rank test). For UVB, the minimal erythema dose within psoriasis was higher than that for non-lesional skin (medians > 112 and 28 respectively, P < 0.05). Laser–Doppler measurements confirmed that the reduced erythemal sensitivity was not due to masking of response by pre-existing increased blood flux within psoriasis. In six patients, the sites subsequently treated twice weekly with PUVA, using high-dose UVA, cleared faster (median number of treatments 3), but with a similar cumulative UVA dose, compared with adjacent lesional skin treated with conventional PUVA (median number of treatments 12). This study demonstrates that psoriasis may clear rapidly, without burning, using high-dose UVA. Availability of a suitable irradiation apparatus would allow rapid and effective PUVA treatment to be used for localized, resistant disease.     

Topical 8-methoxypsoralen increases the efficacy of narrowband ultraviolet B in psoriasis

Background: A combination of oral psoralen with narrowband ultraviolet B (UVB), defined as 'psoralen-narrowband UVB', was shown to have a superior efficacy than UVB alone and even a comparable efficacy to psoralen and ultraviolet A in psoriasis.
Objective: To find out whether topical psoralen-narrowband UVB provides any additional benefit to narrowband UVB alone in psoriasis.
Methods: Nineteen patients with plaque psoriasis were included. Phototherapy was given three times per week. Two symmetrical lesions were selected as target lesions. In the first 12 sessions of phototherapy, the target lesion on one side was treated with 1% 8-methoxypsoralen (MOP) gel 30 min before UVB radiation whereas the target lesion on the other side served as a control. Target lesion scores were assessed at baseline, third, sixth, ninth and 12th sessions. Side effects were recorded.
Results: Sixteen patients completed the study. Target lesion scores decreased significantly on both sides ( P <0.0001). The mean percentage of decreases was greater on the 8-MOP-applied sides compared with the control sides for all assessments, but the difference was statistically significant only at the ninth session (37.7% vs. 58.6%, P =0.043). Pigmentation was frequently seen in 8-MOP gel-applied lesions.
Conclusion: Topical 8-MOP gel plus narrowband UVB has greater efficacy than narrowband UVB alone in psoriasis.     

Topical methoxsalen administration and sunlamp fluorescent irradiation in psoriasis.

Analysis of standard fluorescent sunlamps (Westinghouse) indicates that in addition to UVB (290 to 320 nm), a considerable amount of UVA (320 to 400 nm) is also present in their emissions. Since the benefits of topical psoralen administration and UVA have already been demonstrated, and prior experience by ourselves and others with UVB has indicated that some psoriasis benefited from UVB alone, localized areas and plaques of 20 patients were treated with topical administration of psoralens and fluorescent sunlamp bulbs to determine if such a light source with this emission spectrum would be advantageous. Results indicated a total resolution in 17 of 20 patients after an average of 18 treatments. Adverse blistering phototoxic reactions and excessive hyperpigmentation were not encountered. The UVB erythema response of normal skin served as the guide to light dosage in the same manner as administration of the Goeckerman regimen. Therefore, the use of psoralens was very effective when combined with fluorescent sunlamp irradiation; however, the potential risks of photocarcinogenicity makes this treatment experimental and should be reserved for recalcitrant cases.     

Can ultraviolet erythema be used to identify the basal cell carcinoma phenotype?

Since a prolonged duration of a strong UBV erythema has been suggested as a marker for propensity to develop skin cancer, we objectively followed the duration and intensity of erythemas induced by UVB and UVA radiation for 28 days in 18 patients with basal cell carcinoma (BCC), and in 15 healthy controls using reflectance spectrophotometry. The erythema index, defined as the difference in redness between UV-exposed skin and normal, adjacent skin on the lower abdomen, did not differ significantly between the two groups at 24 h, when the reaction was maximal, following a dose of 6 MED of UVB. Erythema values after 7 and 14 days were slightly higher in the BCC group, but this difference did not reach statistical significance. At day 7 some patients in the BCC group showed very strong erythemas. At days 21 and 28 the two groups had almost identical erythemal reactions. Following a standard dose of UVA of 100 J/cm², patients with BCC and healthy controls both showed weak erythemal reactions, which declined somewhat over the study period. No significant differences in pigmentary response were noted between the BCC and the control group, neither following UVB nor UVA. Although individual patients with BCC deviate from the normal erythemal curve for UVB, the UVB response is not a suitable predictive instrument in screening patients with the basal cell carcinoma phenotype.     

A large scale analytical study on efficacy of different photo(chemo)therapeutic modalities in the treatment of psoriasis,vitiligo and mycosis fungoides

Psoriasis, vitiligo, and mycosis fungoides (MF) are among the most frequently treated dermatological diseases by photo(chemo)therapy. The objectives are to determine which photo (chemo) therapeutic modality could achieve the best response in the treatment of psoriasis, vitiligo, and MF. The design used in this study is retrospective analytical study. The study included 745 patients' records; 293 with psoriasis, 309 with vitiligo, and 143 with early MF, treated in the Phototherapy Unit, Dermatology Department, Kasr El‐Aini Hospital, Cairo University by either psoralen and ultraviolet A (PUVA), narrow band ultraviolet B (NB‐UVB), psoralen and narrow band UVB (P‐NBUVB), broad band UVB (BB‐UVB), or broad band UVA (ΒΒ‐UVA). Data were retrieved from the computer database of the unit and statistically analyzed. In psoriasis, oral and topical PUVA and NB‐UVB were found to be equally effective, whereas oral PUVA had significantly better results than both UVA and BB‐UVB at the end of therapy. In generalized vitiligo, PUVA and P‐NBUVB had significantly better results than NB‐UVB alone. In early MF, there was no statistically significant difference between the response to oral PUVA and NB‐UVB. PUVA and NB‐UVB are good choices in patients with psoriasis and early stage MF, whereas PUVA appears the best choice in the treatment of vitiligo.     

Topical calcipotriol combined with phototherapy for psoriasis. The results of two randomized trials and a review of the literature. Calcipotriol-UVB Study Group.

BACKGROUND: Calcipotrial has a well-documented effect in the treatment of psoriasis. OBJECTIVE: To confirm the beneficial effect of the combination of calcipotriol and UVB and to demonstrate that the combination is safe and well tolerated. METHODS: Data from two randomized right/left studies were analysed. Patients included in the studies had chronic stable plaque-type psoriasis with symmetrical lesions on the arms, the legs and/or the trunk. In one study, 101 patients were treated with calcipotriol on one side and calcipotriol + UVB on the other side of the body (open study). In the other study, 77 patients were treated with calcipotriol + UVB on one side and vehicle + UVB on the other side of the body (double-blind study). Calcipotriol ointment, 50 microg/g, was applied twice daily and UVB 3 times weekly for 8 weeks. UVB was increased from 0.7 MED before treatment in rapid steps up to the erythema threshold. RESULT: In both treatment series the therapeutic effect of the combination of calcipotriol and UVB was enhanced as compared to calcipotriol alone and UVB alone. In the first series there was a significant reduction of the psoriasis area and severity index (PASI) with the combination after 2 weeks as compared to calcipotriol alone. At the end of treatment significantly more sides were cleared after calcipotriol + UVB than after calcipotriol alone. In the other series there was a significantly faster onset of improvement on the sides treated with calcipotriol + UVB than on those treated with vehicle + UVB. After 2 weeks there was a significant difference in PASI in favour of calcipotriol + UVB. At the end of treatment, however, there was no difference between the treatments. There was a similar adverse event profile with either treatment. The addition of UVB to calcipotriol did not alter the tolerability or safety of topically applied calcipotriol. CONCLUSIONS: The result indicates a beneficial effect of combining calcipotriol and phototherapy. The findings are compared to other published studies.     

Monochromatic excimer light (308 nm): an immunohistochemical study of cutaneous T cells and apoptosis-related molecules in psoriasis

BACKGROUND: Various types of UVB radiation source (290-320 nm) are used in treating psoriasis and their therapeutic mechanism has been attributed to immunosuppressive properties. Recently, a new UVB source generated by a 308-nm excimer laser has been introduced for the treatment of psoriasis. OBJECTIVE: In this study we investigated the immunohistochemical evaluation of T cells and the expression of various apoptosis-related molecules in the psoriatic hyperproliferative skin before and after treatment with 308-nm monochromatic excimer light (MEL). METHODS: Ten patients (three women and seven men), ranging in age from 29 to 79 years, affected by plaque-type psoriasis vulgaris, were treated with MEL. Biopsies from psoriatic lesions of MEL-treated sites were taken before, 24 h and/or 48 h after the first irradiation and analysed by the immunophosphatase alkaline technique (APAAP). RESULTS: MEL treatment was found to cause a significant decrease in the rate of proliferation of keratinocytes and a relevant depletion of T cells in all psoriatic lesions, 48 h after the first irradiation: 308 nm light eliminated T cells from the psoriatic epidermis and also from the dermis, highlighting the ability of this UVB source to penetrate the skin compared with normal UVB and establish direct cytotoxic action on T cells infiltrating skin lesions. Rapid clearing of psoriatic lesions involves potential molecular targets of UVB in T cells including p53, which is upregulated after direct irradiation with 308-nm UVB. Moreover, Bcl-2 expression in healing psoriasis epidermis after MEL treatment is significantly decreased compared with untreated skin and the TUNEL (TdT-mediated dUTP-biotin nick end labelling) technique revealed the presence of relevant apoptotic keratinocytes in the irradiated epidermis. CONCLUSIONS: These results indicate that psoriatic skin after monochromatic excimer light therapy is associated with significant T-cell depletion and alterations of apoptosis-related molecules accompanied by a decreased proliferation index and clinical remission.     

Comparison of the antipsoriatic efficacy of heliotherapy and ultraviolet B: a cross-over study.

Ten psoriasis patients who underwent a 4-week heliotherapy period in the Canary Islands were treated with ultraviolet B (UVB) phototherapy at relapse, 2-24 months later. In both settings, psoriasis improvement was monitored using a psoriasis severity index (PSI), and UV exposure was recorded with polysulphone films. In the 8 patients that could be evaluated, a median healing rate of 94% was recorded in the heliotherapy period, with a median cumulative UV dose of 46 erythemal units (EU). In the UVB phototherapy, a median improvement rate of 86% was found after a median cumulative UV dose of 112 EU. It is concluded that, on an erythemal UV dose basis, heliotherapy was more effective than UVB phototherapy in treating psoriasis.     

Psoriasis treatment and a day-care centre: clinical aspects and an attempt at a cost-benefit analysis

The practical results of day-care centre treatment of psoriasis have been studied. Patients referred to the centre are generally those where the skin disease covers substantial body areas. The main treatment has been UVB. UVB plus dithranol or PUVA has been used on patients who have failed to respond to UVB alone. With UVB therapy alone, 263/328 patients healed with a median to healing time of 8 weeks, and 9 weeks to relapse. 34/60 patients with a previously poor response to UVB healed on UVB plus dithranol. Median time to healing was 8 weeks and time to relapse, 12 weeks, 24 patients were treated with PUVA, as they had had a poor earlier response to UVB. All healed with a median time to healing of 12 weeks and 25 weeks to relapse. 3.3% of the patients fit for work have at some time during the treatment been off work due to their psoriasis. The cost for this type of treatment is about one-fifteenth of the cost of treatment on a hospital ward.     

PUVA erythemal sensitivity depends on plasma psoralen concentration and UVA sensitivity

The variation in erythemal sensitivity of the skin during PUVA therapy with oral 8-methoxypsoralen (8-MOP) was examined by measuring both UVA and PUVA erythemal responses, together with plasma 8-MOP concentration, in 27 patients about to start PUVA therapy for psoriasis. The erythema responses were judged visually, and also measured using a reflectance instrument in order to construct dose-response curves. No significant association was found between the UVA and PUVA minimal erythema responses. The plasma psoralen concentration showed significant association with the slope of the PUVA erythema dose-response curve. The slopes of the UVA and PUVA erythema dose-response curves were significantly associated, and this association became much stronger when allowance was made for plasma psoralen concentration. These results show that erythemal sensitivity during PUVA therapy is related to both plasma psoralen concentration and inherent UVA sensitivity, but that this relationship is not apparent when sensitivity is judged visually as the minimal erythema response. The association between PUVA and UVA erythemal sensitivity suggests a common pathway in the vascular response induced hy UVA radiation, with or without psoralen.     

The effectiveness of PUVA treatment in severe psoriasis is significantly increased by additional UV 308-nm excimer laser sessions

In most cases, patients with moderate to severe psoriasis are treated with narrow-band UVB phototherapy or with psoralen UVA (PUVA-) photochemotherapy. This UV-radiation is given to the whole skin, including unaffected skin. Normally, these two PUVA- and UVB-radiation procedures cannot be combined on account of the phototherapeutic side-effects on unaffected skin. The 308-nm excimer laser has been shown to be safe and effective in the treatment of localized mild-to-moderate plaque-type psoriasis whilst sparing healthy skin. Our aim was to compare the therapeutic response to PUVA plus up to 4 UVB308-nm radiations and PUVA monotherapy in patients with moderate-severe plaque-type psoriasis. 272 hospitalized adult patients were enrolled on this prospective random study. 256 patients completed the full course of treatment. PUVA treatment was given 4 times weekly to all patients. 123 patients received PUVA as a monotherapy. During the first two weeks, 149 patients were additionally treated up to four times with 308-nm excimer-derived UVB on the affected skin and treatment was evaluated for its efficacy, duration, number of times necessary for complete (CR) or partial remission (PASI reduction > 90 or > 50%, respectively), cumulative light dose, side effects of therapy and duration of remission after therapy. Statistically, there is no significant difference when comparing the efficacy of PUVA (CR 67.3%) and PUVA plus excimer (CR 63.6%). On average, patients treated by the combination method went into remission in half the treatment time (15 +/- 6 versus 27 +/- 7 days) and with half the cumulative UVA dose (22.9 +/- 5.8 versus 53.2 +/- 26.3), p < 0.05. In conclusion, skin heals considerably quicker when treated with a combination of photochemotherapy and a short course of UVB 308 nm laser treatment applied directly to the affected skin, resulting in a shorter hospital stay and quicker rehabilitation of patients with moderate-severe psoriasis.     

Psoralen-ultraviolet A therapy vs. psoralen-ultraviolet B therapy in the treatment of plaque-type psoriasis: our experience with fitzpatrick skin type IV

BACKGROUND: Oral psoralen, when combined with UVB, shows an increased response in psoriasis. In this study, conventional psoralen-UVA (PUVA) therapy was compared with psoralen-UVB (PUVB) therapy in plaque-type psoriasis in patients with Fitzpatrick skin type IV. PATIENTS AND METHODS: Equal numbers of patients with stable, plaque-type psoriasis were treated with either PUVA (n = 22) or PUVB (n = 22), three times weekly until 90% clearance was achieved. A final evaluation was made 3 months later. RESULTS: The two groups showed no significant differences in terms of clearance of disease, mean number of exposures, or the average duration of therapy; however, the cumulative dose of UVB required for clearance was significantly lower than that of UVA. Both groups had a similar acute side-effects' profile. CONCLUSIONS: PUVB therapy is as effective as conventional PUVA in the treatment of stable, plaque-type psoriasis in patients with Fitzpatrick skin type IV. A significantly lower dose of UVB is required for clearance as compared with UVA.     

Towards optimal regimens for the UVB phototherapy of psoriasis: a mathematical model

A mathematical model is described that predicts the response of psoriasis to a treatment course of UVB irradiation. The basis of the model is that UVB acts by a direct effect on keratinocytes and that cell cycle arrest is the major mode of action in the phototherapeutic response in psoriasis. Although it is unlikely that UVB causes resolution of psoriatic plaques through a single mechanism, the current model has been based on epidermal cell cycle arrest and entry into the terminal differentiation compartment because this is likely to be a significant rate-limiting factor in determining response to treatment. The model has been validated against results obtained from published clinical studies on narrowband (TL-01) UVB phototherapy for psoriasis. The principal outcomes of the model are that for a given erythemal response, the number of exposures required for clearance is almost independent of the frequency with which patients attend for treatment and that the higher the exposure dose per treatment, the more rapidly will clearance result. The model has been used to suggest optimal regimens for the treatment of outpatients and inpatients.     

NB‐UVB (311–312 nm)‐induced lentigines in patients with mycosis fungoides: a new adverse effect of phototherapy

Background Lentigines are a common pigmentary disorder in adults and in patients treated by psoralen and ultraviolet A (PUVA) radiation. Their appearance following treatment with narrow‐band ultraviolet B (NB‐UVB) radiation has been reported in only two patients. Objective To describe the clinical and histological features of NB‐UVB‐induced lentigines their relation to dosimetry and the course of the eruption in patients with mycosis fungoides (MF). Methods The files of all patients with MF treated in our department in 2003–2010 were searched to identify those in whom lentigines appeared following monotherapy with NB‐UVB radiation. Results Of the 73 patients with early stage MF identified, 10 met the study criteria. Lentigines were detected in skin previously involved by MF in seven patients, and in both involved and uninvolved skin in three patients. They appeared during therapy in three patients, after a mean of 56 exposures (range 50–61), and several months (mean 7.8) following completion of treatment in seven patients, after a mean of 69 exposures (range 32–157). Histopathological study of lesions from five patients revealed basal hyperpigmentation relative to adjacent normal‐looking skin. Two lesions had a slight increased number of normal‐looking melanocytes on immunohistochemical staining with melanoma cocktail. One lesion had elongated rete ridges. The lesions persisted throughout follow‐up (mean 26.7 months) in 8 patients. Conclusions Patients with MF treated with NB‐UVB may acquire lentigines. As opposed to PUVA‐induced lentigines which are a known common side‐effect of long‐term treatment, NB‐UVB‐induced lentigines are uncommon but appear earlier, even after a few months of treatment.     

Treatment of actinic prurigo with PUVA: mechanism of action

Five patients with actinic prurigo were treated twice weekly with PUVA. One area on the back was shielded from UVA throughout the 15-week treatment period. Before PUVA, all patients had increased erythemal sensitivity to UVA and showed abnormal augmentation of UVB erythema by topical indomethacin. After PUVA, all patients were free of photosensitive symptoms and skin that had been exposed to UVA showed normal erythemal responses. By contrast, the areas of skin that had been protected from UVA showed erythemal responses that were unchanged from pre-PUVA values. Augmentation of UVB erythema by topical indomethacin persisted, both on UVA exposed and UVA protected skin. These results show that, although PUVA is an effective treatment in actinic prurigo, it does not alter the underlying mechanism of photosensitivity. The protective effect is local and is due presumably to an increase in melanin pigmentation and epidermal thickness.     

The time-course of psoralen ultraviolet A (PUVA) erythema.

The time-course for the development of ultraviolet A-induced erythema in psoralen-sensitized skin differs from that caused by ultraviolet B or ultraviolet A but objective data are not available. During psoralen ultraviolet A therapy, the minimal phototoxic dose is determined 72 h after exposure, when psoralen ultraviolet A erythema is assumed to be maximal. This measurement is of fundamental importance in optimizing the therapeutic regimen. We examined a detailed time-course for development of psoralen ultraviolet A erythema in 16 subjects. The erythemal responses to ultraviolet B, ultraviolet A and psoralen ultraviolet A were assessed visually and using a reflectance device. Ultraviolet B erythema was maximal 24 h after exposure compared with subsequent time-points. Psoralen ultraviolet A erythema was evident at 24 h, with reduction in the median ultraviolet A minimal erythema dose from 14 to 5 J per cm2 in the presence of psoralen (p < 0.01; n = 9). Peak psoralen ultraviolet A erythema, assessed by minimal phototoxic dose, did not occur until 96 h or later in 75% of subjects. Using individual dose- response curves, we determined that only 67% of mean maximum psoralen ultraviolet A erythemal intensity had developed by 72 h. Furthermore, at the time of maximal erythema, the slope of the psoralen ultraviolet A dose-response curve was approximately 2-fold shallower than that for ultraviolet B-induced erythema. If assessment of psoralen ultraviolet A erythemal sensitivity had been made at 96 h instead of the conventional 72 h time-point, peak erythemal responses would not have been missed in any of the subjects. Based on these findings, it seems appropriate to consider whether psoralen ultraviolet A minimal phototoxic dose measurements should be performed 96 h after exposure.     

Calcipotriol vs. tazarotene as combination therapy with narrowband ultraviolet B (311 nm): efficacy in patients with severe psoriasis

BACKGROUND: Phototherapy has been shown to be one of the most effective treatment modalities for patients with psoriasis. Nevertheless, photocombination therapies capable both of reducing cumulative ultraviolet (UV) doses and of accelerating clearance of skin lesions are important and of high interest. There have been no published studies comparing the effect of narrowband UVB irradiation in combination with topical application of tazarotene vs. calcipotriol. OBJECTIVES: To determine, in a half-side manner, whether a combination of UVB (311 nm) and tazarotene is superior to UVB (311 nm) plus calcipotriol or vice versa. METHODS: Ten patients suffering from widespread symmetrical psoriasis were treated for at least 4 weeks with topical calcipotriol and tazarotene in a half-side distribution. Additionally, the whole body was irradiated with narrowband UVB (311 nm) four times a week. Before treatment and once weekly during therapy a modified Psoriasis Area and Severity Index was estimated for each body half. The total treatment time, number of treatment sessions and cumulative UVB dose necessary for clearance of skin lesions were determined in an observer-blind fashion for each patient. Furthermore, all patients completed a quality of life questionnaire. RESULTS: Clearance of psoriasis was observed after a median of 19 treatment sessions (range 14-28) and a median cumulative UVB dose of 22.98 J cm-2 (range 9.24-58.22) simultaneously for both body halves. On the side treated with topical tazarotene gel, four patients complained of itching and dryness of the skin, and skin irritation was observed in three of them. Six patients preferred the application of tazarotene gel, while four preferred calcipotriol. CONCLUSIONS: Our clinical comparison of narrowband UVB with either topical calcipotriol or topical tazarotene revealed no significant therapeutic difference between both regimens. Although these results need to be confirmed in larger patient groups, we feel that both photocombination therapies can broaden the therapeutic options for moderate to severe psoriasis vulgaris and may reduce the cumulative UVB dose during therapy.     

Treatment with 311-nm ultraviolet B enhanced response of psoriatic lesions in ustekinumab-treated patients: a randomized intraindividual trial

Background Treatment with the interleukin‐12/23 antibody ustekinumab produces a satisfactory response [i.e. 75% reduction in Psoriasis Area and Severity Index (PASI) compared with baseline (PASI 75)] in the majority of patients with moderate to severe chronic plaque‐type psoriasis. Objectives To determine whether concomitant 311‐nm ultraviolet (UV) B therapy can further enhance the response in patients with psoriasis treated with ustekinumab. Methods Ten patients (five women and five men; mean age 58 years, range 48–66) with moderate to severe plaque‐type psoriasis were treated with ustekinumab at a standard dosage of 45 or 90 mg subcutaneously depending on body weight (below or above 100 kg) at weeks 0 and 4. Within 2 days after ustekinumab initiation, the minimal erythemal dose (MED) was determined and suberythemal MED 311‐nm UVB‐based phototherapy was thereafter administered to one randomly selected body half (left or right, excluding the head) three times weekly for 6 weeks. Treatment response was monitored weekly in terms of half‐body PASI. Results Nine patients completed the study. Analysis of their data showed that 311‐nm UVB significantly accelerated the therapeutic response. At baseline (i.e. start of 311‐nm UVB therapy), the mean PASI was similar in both irradiated and unirradiated body halves (13·6 vs. 13·3). At week 6, however, it was lower on irradiated body halves (2·5 vs. 6·1). This difference of 3·6 (95% confidence interval 1·3–5) was statistically significant and corresponded to an overall mean PASI reduction from baseline of 82% vs. 54%, respectively. At week 6, PASI 75 was achieved significantly more often on UV‐irradiated body halves than on unirradiated body halves [7/9 patients (78%) vs. 1/9 (11%)] (McNemar test, P = 0·007). At week 12, this synergistic effect of 311‐nm UVB was still apparent although not significantly so. Conclusions Treatment with 311‐nm UVB accelerates the clearance of psoriatic lesions in ustekinumab‐treated patients.     

Phototherapy in the perspective of the chronicity of psoriasis

According to the guidelines for the treatment of psoriasis, phototherapy is given in courses of UVB exposure starting at 50–70% of the minimal erythema dose, MED, with subsequently incremental dosages, but keeping erythemal skin reactions to a minimum by restraining the dosages when necessary. In this review, this classical principle of short-term near erythematogenic UVB therapy without further UVB maintenance therapy is challenged as it is evidently not optimal for psoriasis as a chronic condition. There is old experimental evidence supplemented with growing knowledge on the mode of action of phototherapy and more recent data on low-level UVB regimens as maintenance therapy that should urge us to revisit our guidelines on phototherapy to address psoriasis for what it is: a chronic condition.     

Fumaric acid esters in combination with a 6‐week course of narrowband ultraviolet B provides an accelerated response compared with fumaric acid esters monotherapy in patients with moderate‐to‐severe plaque psoriasis: a randomized prospective clinical study

Psoriasis is a chronic recurring inflammatory skin condition with a significant impact on patients’ quality of life. It affects about 2–3% of the population in Western countries and is due to a dysregulation of the immune system. The cause and development of psoriasis is complex and involves both genetic and environmental factors. Plaque psoriasis is the most common type of psoriasis and causes raised red skin lesions with a silvery white flaky surface. There is no cure for psoriasis but current treatments can hold symptoms at bay. Fumaric acid esters (FAE) are amongst the first‐line treatments in European countries where this medication is available. FAE are effective and generally safe but take a while to start working. A short‐term combination with narrow‐band ultraviolet (NB‐UVB) phototherapy might overcome this drawback and help to accelerate the response in the early stage of treatment. Our randomized controlled prospective trial was designed to investigate whether an initial addition of NB‐UVB to FAE improves the clinical response and quality of life in patients with plaque psoriasis. The researchers who performed this study are based at the Department of Dermatology, Medical University of Vienna, Austria. The patients were randomly (by chance) assigned to two treatment groups: one group received treatment with FAE alone and the second group received a combination of FAE and a 6‐week course of narrow‐band UVB. We found that adding a short course of NB‐UVB to FAE both accelerated and improved the clearing of psoriasis and the patients’ quality of life.