Age dependence of ultraviolet light-induced erythema following narrow-band UVB exposure

Treatment Strategies for Chronic Pruritus and Eczema/Dermatitis in Older Adults Under the Category of Chronic Eczematous Eruptions of Aging (CEEA)

Chronic eczematous eruptions of aging (CEEA) refers to a heterogenous group of longstanding, pruritic eczematous dermatoses with an unidentified etiology, or those which do not meet strict disease criteria. The literature has not yet established a single ubiquitous disease or term for these eruptions in adults over the age of 65 years. Instead, CEEA is attributed various names, including immunologic eruption of aging, and eruption of immunosenescence. Atopic dermatitis in the elderly, eczema in the elderly, and late- or adult-onset atopic dermatitis or eczema likely also fall under the umbrella of CEEA, given that older patients often do not meet strict criteria for atopic dermatitis. As a reflection of such terminological heterogeneity, CEEA does not have a standardized workup algorithm. This lack of uniformity can obscure the ability to study and understand appropriate treatments for this condition. Yet, as providers become increasingly aware of CEEA and more comfortable in making this diagnosis in older adults, it is necessary that dermatologists understand the safety and efficacy of common CEEA treatments in this population. Here, we discuss special considerations, challenges, and recommendations for treating older adults with CEEA with topical and systemic therapeutics. We provide an overview of therapeutic strategies and potential barriers to treatment and discuss the essential role of shared decision making when caring for this patient population.

Narrow-band phototherapy in the treatment of atopic dermatitis: mechanisms of action, methodology of implementation

Phototherapy is widely used to treat various chronic skin diseases. One of the most effective methods of treatment is narrow-band medium-wave ultraviolet radiation with a wavelength of 311 nm (UVB-311). UVB-311 is used for such immune-mediated diseases as atopic dermatitis, psoriasis, vitiligo, mycosis fungoides and others. Despite the fact that the method was developed more than 30 years ago, the exact mechanism of its therapeutic action remains insufficiently studied. To date, most of the effects of UVB-311 are explained by its effect on the immune cells of the skin. This review examines data on the effects on the main molecular targets, including T-lymphocytes, keratinocytes, Langerhans cells, cytokine profile, epidermal barrier proteins. Data on the features of the pathogenetic effect of UVB-311 on the immune mechanisms of pathogenesis in atopic dermatitis were obtained. The issues of dosing by determining the minimum erythemic dose (MED) or skin phototype, methodology of procedures are discussed. Prospects for further study of photobiological aspects of UVB-311 action are determined.

Safety concerns with current treatments for psoriasis in the elderly

Introduction: The approach to manage psoriasis in the elderly (ages ≥65 years) patients can be challenging. They often suffer from multiple comorbidities and polypharmacy with possible adverse effects and undergo a progressive functional impairment of the immune system that increases susceptibility to infections as well as to auto-reactivity. Despite the increasing aging of the general population and although several therapies are currently available for psoriasis treatment, data regarding their use and tolerability in the elderly are quite limited.Areas covered: This review focuses on topical and systemic therapies that have been investigated in elderly patients in order to provide their safety profile in this population.Expert opinion: Conventional systemic therapies in elderly patients should be carefully dispensed and the correct dosage individually determined, taking into account the metabolism changes, organ impairment, comorbidities, concomitant medications, and contraindications. Apremilast, due to its satisfactory safety profile and low risk of drug interactions, results as an appropriate treatment option for elderly patients. Biologics (TNF-α, IL-12/23, IL-17, and IL-23 inhibitors) come out as safe and long-term options for the management of these patients resulting not associated with a higher risk of adverse events.

Management of Itch in the Elderly: A Review

Chronic itch is common in the elderly patient and may be caused by a variety of known dermatologic and non-dermatologic conditions and can have a significant effect on quality of life. Age-related changes in barrier function, immunosenescence, and neuronal changes and neuropathies are common predisposing factors to chronic itch in this age group. Certain primary dermatologic conditions are more common in the elderly and can cause chronic itch. Also, co-morbid diseases particularly of the renal, hepatobiliary, or hematologic systems, psychologic conditions, or medications may contribute to chronic itch in this population. Thus, medical workup for an elderly patient with chronic itch requires special attention to the patient's medical history, current health status, and medications. Topical treatments and emollients may be recommended for elderly patients, with consideration of specific adverse effects and alternatives. Systemic medications pose a higher risk of adverse effects and many are contraindicated in the elderly for this reason. In addition, management in the elderly may be complicated by differential pharmacokinetics of medications, the presence of co-morbid health conditions, cognitive disorders, physical limitations, and polypharmacy. New and emerging treatment modalities hold promise for use in the elderly due to these special considerations.

Skin Burn Associated With Photochemotherapy

OBJECTIVE

psoralen and ultraviolet A (PUVA) phototherapy (PT) has become a standard treatment for several severe skin diseases. Photosensitization is done by oral psoralen intake. In minor cases, PUVA can lead to skin changes like erythema and hyperpigmentation. However, it can also lead to severe burn injuries when exposed to extensive UV light. This makes the treatment in a burn center inevitable.

METHODS

We report the clinical observation of a 38-year-old man presenting with an extensive burn injury caused by sun tanning after PUVA PT.

CONCLUSIONS

There are just few cases of extensive burns induced by PUVA PT. Prevention becomes manifest in patient information, correct calculation of dosage, evaluation of photosensitivity, and close observation. In cases of severe burn injuries, patients should be referred to a burn center for optimal conservative treatment. Surgical intervention is usually not necessary.

Is it Useful to Calculate Minimal Erythema Dose Before Narrowband UV-B Phototherapy?

INTRODUCTION AND OBJECTIVES

The starting dose for narrowband UV-B phototherapy is determined by a patient's skin phototype or minimal erythema dose (MED). Calculation of MED identifies patients with unsuspected photosensitivity. The aim of this study was to investigate the influence of factors such as concomitant use of photosensitizing agents, diagnosis, and combination with acitretin in patients with psoriasis on the frequency and severity of adverse effects in patients with a low MED to narrowband UV-B phototherapy.

MATERIAL AND METHODS

We undertook a retrospective observational cohort study between February 1, 2009 and March 31, 2015. MED values were classified as normal or low.

RESULTS

In total, 302 patients with different skin conditions started narrowband UV-B phototherapy at a dose determined by their MED. No differences were found between patients with a low MED and those with a normal MED for number of drugs taken (P=.071) or use of photosensitizing agents (P=0.806). Following adjustment for age, sex, and phototype, the multivariate analysis showed that psoriasis exerted a protective effect against a low MED (OR=0.31 [95% CI, 0.16-0.58]). No significant risk of erythema or pruritus was detected in patients with a low MED (OR=1.68; 95% CI, 0.91-3.29 and OR=2.04; 95% CI, 0.99-4.22, respectively).

CONCLUSIONS

Psoriasis protects against a low MED. Although erythema and pruritus were more common in patients with a low MED, the differences were not significant.

Effects of narrow band UVB (311 nm) irradiation on epidermal cells

Ultraviolet radiation (UVR) is known to be one of the most important environmental hazards acting on the skin. It was revealed that chronic exposure to UVR accelerates skin aging, induces immunosuppression and may lead to the development of skin cancers. On the other hand, UVR has been shown to be effective in the treatment of numerous skin diseases and thus, various phototherapy modalities have been developed to date. Narrow-band ultraviolet B (NB-UVB) emitting a light with a peak around 311 nm has been demonstrated to be effective in the treatment of various skin disorders; currently it is one of the most commonly used phototherapy devices. Despite NB-UVB has been developed more than 30 years ago, the exact mechanism of its therapeutic action remains poorly understood. To date, most of NB-UVB effects were attributed to its influence on immune cells; however, nearly 90% of NB-UVB irradiation is absorbed by epidermis and keratinocytes seem to be important players in mediating NB-UVB biological activity. Here, we have reviewed the current data about the influence of NB-UVB on epidermal cells, with a special emphasis on cell proliferation and death.

Lipidome of narrow-band ultraviolet B irradiated keratinocytes shows apoptotic hallmarks

BACKGROUND

UV light triggers a variety of biological responses in irradiated keratinocytes that might be associated with global perturbation of their lipidome. However, lipids that are specifically affected and the exact molecular mechanisms involved remain poorly understood.

OBJECTIVES

To characterize time-dependent changes of the lipidome of cultured keratinocytes induced by narrow-band ultraviolet B (NB-UVB) irradiation.

METHODS

Immortalized human keratinocytes (HaCaT) were cultured under standard conditions, irradiated with NB-UVB light (311 nm) at 400 and 800 mJ/cm(2) and collected 1, 2, 3, 6, 12 and 24 h later for lipid extraction. Lipid extracts were separated on silica plates in chloroform/ethanol/water/triethylamine (35:40:9:35) and in n-hexane/ethylacetate (5:1) followed by quantitative shotgun lipidomics analysis.

RESULTS

Irradiation with 800 mJ/cm(2) of NB-UVB altered morphology and lipidome composition of HaCaT cells. Ceramide content increased two-fold 6- and 12-h postirradiation with 800 mJ/cm(2), followed by threefold increase in triacylglycerols (TAGs) that peaked at 24 h. In addition, we observed marked increase of various phosphatidylcholine and phosphatidylethanolamine ethers, whereas phosphatidylcholine-species with short-chain fatty acid moieties decreased. The abundance of other lipid species was altered to lesser extent or remained unchanged.

CONCLUSIONS

NB-UVB affected the cellular lipidome of keratinocytes in strictly apoptosis-specific manner.

Sun-induced changes in stratum corneum function are gender and dose dependent in a Chinese population

Previous studies have demonstrated that UVB radiation changes the epidermal permeability barrier and stratum corneum (SC) hydration. It is well known that sun exposure causes erythema, sunburn and melanoma. However, whether daily sun exposure alters SC integrity and epidermal permeability barrier function is largely unknown, especially in Chinese subjects. In the present study, we assess the SC integrity, SC hydration and epidermal permeability barrier function following various doses of sun exposure. A total of 258 subjects (124 males and 134 females) aged 18-50 years were enrolled. A multifunctional skin physiology monitor (Courage & Khazaka MPA5) was used to measure SC hydration and transepidermal water loss (TEWL) on the forearms. In males, basal TEWL was higher with higher doses of sun exposure than with lower doses and control, whereas in females, basal TEWL was higher with lower doses of sun exposure than with higher doses and control. In the group with higher doses of sun exposure, TEWL in females was significantly lower than that in males. The barrier recovery was faster in females than in males in both control and lower-dose groups. In both males and females, barrier recovery was delayed with higher doses of sun exposure. In males, sun exposure did not alter SC hydration, while in females SC hydration was lower with lower doses of sun exposure as compared with control and higher doses of sun exposure. These results demonstrated that sun-induced changes in SC function and SC hydration vary with gender and the extent of sun exposure.

Narrow-band UVB-induced externalization of selected nuclear antigens in keratinocytes: implications for lupus erythematosus pathogenesis

The aim of this study was to analyze whether sera obtained from patients with lupus erythematosus (LE) react with membrane structures found on keratinocytes irradiated with narrow-band ultraviolet B (NB-UVB). We applied atomic force microscopy (AFM) to visualize cell surface structures expressing nuclear antigens upon apoptosis following NB-UVB irradiation. Immortalized human keratinocytes (HaCaT) were cultured under standard conditions, irradiated with 800 mJ cm(-2) NB-UVB light and imaged by AFM mounted on an inverted optical microscope. It was observed that NB-UVB irradiation provoked significant alterations of the keratinocyte morphology and led to the membrane expression of antigens recognized by anti-La and anti-Ro 60 kDa sera but not by antidouble-strand DNA sera. The presence of La and Ro 60 kDa antigens on keratinocyte surfaces after NB-UVB irradiation was limited mainly to the small bleb-like protrusions found on the keratinocytes by AFM. A closer investigation by AFM also revealed that some structures positively stained with anti-Ro 60 kDa serum were also located submembranously. We hypothesize that the externalization of some nuclear antigens because of NB-UVB exposure might be responsible for exacerbation of skin symptoms in patients suffering from LE.

Structural alterations provoked by narrow-band ultraviolet B in immortalized keratinocytes: assessment by atomic force microscopy

We applied atomic force microscopy (AFM) to visualize ultrastructural changes of the keratinocyte morphology after narrow-band ultraviolet B (NB-UVB) irradiation. Immortalized human keratinocytes were cultured under standard conditions, irradiated with NB-UVB light at doses ranging from 50 to 800 mJ/cm2 and imaged by AFM mounted on an inverted optical microscope. It was observed, that NB-UVB irradiation provoked dose-dependent alterations of the keratinocyte morphology. While the surface of non-irradiated cells exhibited homogenously distributed crest-like shaped protrusions (height 0.16 +/- 0.05 microm), cells irradiated with a dose of 800 mJ/cm2 in addition showed round shaped protrusions (height 0.14 +/- 0.06 microm) distributed predominantly around the nucleus and bleb-like protrusions irregularly distributed on the cell surface (height 0.95 +/- 0.29 microm). These irradiated cells easily detached from the supporting glass surface, showed impaired contact with adjacent keratinocytes and significantly rearranged their cytoskeleton network. We hypothesize that these structural and functional alterations reflect ongoing apoptosis in UVB treated cells.

Documento de consenso sobre fototerapia: terapias PUVA y UVB de banda estrecha

It is essential to develop a consensus document on phototherapy in order to adapt this procedure to the specific characteristics, needs and reality of our milieu. Using a review of existing literature on the subject and the experience of its own members as a reference, the Spanish Photobiology Group (GEF) of the Spanish Academy of Dermatology and Venereology (AEDV) has developed some therapeutic guidelines for the most widely used modes of phototherapy: PUVA therapy and narrow-band UVB (NBUVB) therapy. These guidelines deal with generalities about the equipment, calibration and regulation in phototherapy booths, and the concept and indications for these forms of treatment are reviewed. Recommendations are also proposed regarding patient selection, therapeutic procedures, associated pharmacological agents of interest and the prevention and management of adverse effects. The consensus document is designed as a flexible and practical instrument intended for use in daily clinical practice, aimed at optimizing the possibilities of phototherapy while reducing risks for patients and therapists.

Phototherapy with narrowband vs broadband UVB

Phototherapy with ultraviolet (UV) radiation of wavelengths between 280 and 320 nm (UVB) is a safe and effective treatment for a variety of diseases. In addition to standard broadband UVB (bUVB), narrowband phototherapy with fluorescent bulbs emitting near monochromatic UV around 311 nm (nUVB) has become an important treatment for diseases such as psoriasis, atopic dermatitis and vitiligo. In addition to these indications, the number of diseases for which nUVB phototherapy is reported to be effective is continuously growing. The differential effects of nUVB phototherapy in comparison to other UV wavelengths as well as established and new indications for this treatment modality are reviewed.