[Photodermatoses during childhood]

Actinic dermatitis and phototoxic and idiopathic photodermatoses occur relatively often during childhood. Photodermatoses stemming from enzyme defects and genetic disorders are much less common, while photoallergic and chronic actinic dermatitis have not been dealt with to date. A specific sensitivity of a child's skin to light is often the first manifest clinical symptom of a photodermatosis, the key is to ensure early diagnosis. However, it is often difficult to reach a diagnosis, as the lesions are barely perceptible or have even healed by the time the patient is examined. This is why photoprovocation tests are so important in diagnosing photodermatoses, particularly during childhood. In addition to early diagnosis of these illnesses and offering the appropriate treatment, it is also crucial that the parents be well informed and aware of what symptoms to look for so that they can protect their children from overexposure to UV light and thereby avoid later actinic injuries that can become as serious as malignancies.

Temperature- and time-resolved X-ray scattering at thin organic films

Multilayers of an Fe(II)-polyelectrolyte-amphiphile complex (Fe-PAC) were investigated simultaneously by energy-dispersive X-ray reflectivity and in-plane diffraction at the bending-magnet beamline at BESSY II. By recording spectra between room temperature and about 348 K with a time resolution of about 60 s, two phase transitions were identified and the respective activation energies were determined. Owing to a fixed geometrical set-up, an energy-dispersive experiment is suitable for measuring X-ray reflectivity and in-plane X-ray diffraction of thin organic films simultaneously. Installed at a bending magnet at BESSY II and using an energy range of 4 < E < 25 keV, both reflectivity and diffraction spectra can be collected within about 60 s. The performance is demonstrated by temperature- and time-resolved measurements of the phase transition behaviour of multilayers of an Fe-PAC deposited on a silicon support by means of the Langmuir-Blodgett (LB) technique. By measuring the X-ray reflectivity while increasing the temperature, it is shown that the original LB phase is not stable and transforms irreversibly into a liquid-crystalline (LC)-like phase at about 318 K. At the same temperature the in-plane diffraction signal vanishes reversibly, reflecting rotational disorder of the hexagonal arrangement of amphiphilic chains. Its activation energy is determined to be about 1.3 eV. At about 338 K a second irreversible phase transition occurs to another LC phase with smaller vertical layer spacing. This transition is reversible between 329 K and 338 K.

Upregulation of epidermal surface molecule expression in primary and ultraviolet-induced lesions of lupus erythematosus tumidus

BACKGROUND

Lupus erythematosus tumidus (LET), a photosensitive skin disorder with characteristic clinical and histological features, has not been generally accepted as a subset of cutaneous lupus erythematosus (CLE).

OBJECTIVES

To analyse the expression of epidermal surface molecules in skin biopsy specimens from patients with LET and to relate the results to other variants of CLE, such as discoid lupus erythematosus (DLE) and subacute CLE (SCLE).

METHODS

In total, 45 patients with different subtypes of CLE were included in the study, and cryostat sections from primary and ultraviolet (UV) A- and UVB-induced skin lesions were investigated using immunohistochemical methods.

RESULTS

In contrast to healthy controls, skin lesions of LET showed upregulation of intercellular adhesion molecule-1 (ICAM-1) and histocompatibility class II molecules (HLA-DR), with an expression pattern resembling that seen in DLE and SCLE. Furthermore, staining with a monoclonal antibody against 27E10, a distinct marker for cell activation and differentiation, revealed intense focal or band-like labelling of all epidermal layers independent of the type of lesion.

CONCLUSIONS

Expression of epidermal surface molecules such as ICAM-1, HLA-DR and 27E10 is equally upregulated in primary and UV-induced lesions of patients with LET, DLE and SCLE. These results support our recent clinical findings that LET represents a distinct subset of CLE with a similar immunopathomechanism rather than a different disease.

The 5-aminolevulinic acid-induced porphyrin biosynthesis in benign and malignant cells of the skin

In fluorescence diagnosis and photodynamic therapy of neoplastic tissues 5-aminolevulinic acid is used to synthesize endogenous porphyrins as photosensitizers. The efficacy of neoplastic tissues to fluorescence diagnosis and photodynamic therapy is thought to be dependent on the total level of intralesional formed porphyrins. The available profiles of porphyrin metabolites in normal and in neoplastic cell lines after administration of 5-aminolevulinic acid vary considerably. Thus, this is the first in-vitro study which compares the porphyrin biosynthesis in normal skin cells (HaCaT, fibroblasts) with melanoma cells (Bro, SKMel-23, SKMel-28). After incubation with 1 mM 5-aminolevulinic acid, kinetics of porphyrin levels and metabolites were determined in the cells and the corresponding supernatants. Exogenous 5-aminolevulinic acid induced porphyrin formation in all cells with maximum values after an incubation period of 16-36 h. Increase of porphyrin levels varied from 10- to 80-fold (SKMel-28>HaCaT>fibroblasts>SKMel-23>>Bro) with minimum 1.5 times higher levels of porphyrins in the supernatants than in the cells. In cells and supernatants protoporphyrin and coproporphyrin were the predominantly formed porphyrin metabolites. Metastatic melanoma cells (SKMel-23, SKMel-28) accumulated much higher porphyrin levels than primary melanoma cells (Bro). In conclusion, by optimizing the treatment modalities, especially the light source, topical photodynamic therapy (PDT) could become a treatment alternative of melanoma metastases in progressive disease.

Role of integrin alphaE(CD103)beta7 for tissue-specific epidermal localization of CD8+ T lymphocytes

Tissue-specific T cell localization is crucial for immune surveillance of normal tissues and the pathogenesis of inflammatory disorders. In psoriatic skin, CD8+ lymphocytes predominantly reside within the epidermis, whereas CD4+ T cells are most abundant within the dermis. Molecular mechanisms guiding this spatial compartmentalization are not completely understood, however. Here, we demonstrate that 55% (+/-9.7%, n = 14) of the epidermal T cells, predominantly of the CD8+ phenotype, expressed the integrin alphaE(CD103)beta7. In contrast, only 5% (+/-2.0%) of the dermal T cells were alphaE(CD103)beta7+. Integrin alphaE(CD103)beta7 was not detected in normal skin (n = 10), and less than 1% of peripheral blood lymphocytes derived from normal (n = 11) or psoriatic (n = 10) donors expressed alphaE(CD103). When cultured T lymphoblasts (n = 12 donors) were stimulated with transforming growth factor beta1, expression of integrin alphaE(CD103)beta7 was induced on 52.8% (+/-16.2%) of CD8+ cells, but only on 6.1% (+/-2.3%) of CD4+ cells, suggesting selective inducibility on CD8+ lymphocytes. Whereas similar overall expression of transforming-growth-factor-beta1-specific mRNA was detected in normal and psoriatic skin by real-time quantitative polymerase chain reaction, immunohistochemistry revealed focal overexpression of transforming growth factor beta1 underneath psoriatic, but not normal, epidermis. This heterogenous transforming growth factor beta1 expression may contribute to induction of alphaE(CD103) in vivo. Adhesion of transforming-growth-factor-beta1-stimulated CD8+, but not CD4+, T cells to cultured keratinocytes and psoriatic epidermis in frozen sections could be significantly inhibited by antibodies that blocked the alphaE(CD103)/E-cadherin interaction. Co-culture of lymphoblasts and keratinocytes resulted in marginal enhancement of alphaE(CD103)beta7 expression in some cases. Overall, integrin alphaE(CD103)beta7 appears to contribute to tissue-specific epidermal localization of CD8+ T lymphocytes.

[Rediscovery of thalidomide. Successful treatment of discoid lupus erythematosus]

Thalidomide, an oral drug introduced in Germany in 1953 as a mild sedative, was withdrawn from the world market when its teratogenic effect was discovered some years later. It has since been selectively reintroduced to treat a variety of autoimmune or inflammatory diseases such as erythema nodosum leprosum, prurigo nodularis, graft-versus-host disease, and discoid lupus erythematosus (DLE). We report on three patients with long-standing, severe DLE showing no response to systemic first-, second- and third-line treatments. After four weeks of therapy with thalidomide the skin lesions had improved dramatically and after three to six months all three patients responded with an almost complete remission. The side effects of thalidomide, especially somnolence and paresthesias, were minor and well tolerated by the patients. Our data confirm that thalidomide provides one of the most useful therapeutic alternatives for chronic refractory DLE, despite the risks of teratogenicity and polyneuropathy.

Penetration kinetics of 8-methoxypsoralen after 8-methoxypsoralen bath procedure with and without UVA irradiation

Administration of 8-methoxypsoralen (8-MOP) in a dilute bath water solution is an effective therapeutic alternative for systemic application of 8-MOP, avoiding systemic side effects such as nausea and cataractogenesis. The aim of our study was to determine the epicutaneous penetration of 8-MOP in a dilute bath water solution with and without additional UVA irradiation in human skin under in vitro conditions. To simulate the PUVA bath procedure, 8 skin samples were exposed to radioactively labeled 8-MOP in a water solution. After 20 min, the test solution was removed and the skin surface was dried. Immediately after the bath procedure, 4 of the skin samples were irradiated with 0.5 J/cm2 UVA. During a test period of 15 h, the 8-MOP penetration was observed. In both test groups (with and without UVA irradiation) 8-MOP permeated through all skin layers between 30 min and 1 h after application. Compared to the unirradiated skin samples, the UVA-irradiated skin samples showed a significantly slower increase and a lower maximum of 8-MOP permeation. Following our results, UVA irradiation of 8-MOP-exposed skin samples led to a significantly decreased permeation rate. This might be due to UVA-induced links between 8-MOP molecules and human DNA. In addition, we investigated the levels of radioactivity emitted by tritium-labeled 8-MOP in stratum corneum, epidermis and dermis up to 30 min after 8-MOP bath in two further test groups with and without additional UVA irradiation. The statistical analysis revealed no significant differences between these two test groups. Thus, the levels of radioactivity remained constant in the epidermis and dermis during the test period of 30 min. Since the levels of radioactivity were constant up to 30 min after UVA irradiation, a previously supposed marked loss of 8-MOP concentration might not be responsible for the rapid extinction of observed in vivo photosensitivity within 1 h after PUVA bath observed in vivo in human skin.

Phototesting in lupus erythematosus: a 15-year experience

It has long been observed that sun exposure can induce or exacerbate skin lesions in patients with certain forms of lupus erythematosus. Despite the frequency of photosensitivity in these patients, the mechanism by which ultraviolet radiation alters the pathogenic course of this disease remains poorly understood. After development of standardized test methods, our group demonstrated in 1986 that skin lesions in patients with lupus erythematosus can be experimentally reproduced by UVA and UVB irradiation. In the following years, phototesting has received much attention as a valid model to study photosensitivity of different forms of lupus erythematosus and the pathogenetic mechanism of this disease. Further investigations have also made it possible to find genetic and immunologic factors associated with photosensitivity and have helped to identify the pathophysiologic steps involved in the induction of such skin lesions. We present phototesting results and clinical correlations of more than 400 patients with different forms of lupus erythematosus and discuss the recent advances in provocative phototesting.

Aminolevulinic acid: pharmacological profile and clinical indication

The role of aminolevulinic acid hydrochloride (ALA) in photodynamic therapy (PDT) of in situ neoplasias and tumours of epithelial tumours is steadily increasing and it has been shown to be the drug with most clinical use in PDT. In dermatology, topical PDT with ALA is already postulated to be the treatment of choice for actinic keratoses and superficial basal cell carcinomas. In gastroenterology, pulmonology, uro- and nephrology, neurology and gynaecology ALA has an important role as a photosensitiser not only in the diagnosis of neoplastic tissue but as therapy; first experiences have been made with PDT in these organs. Besides the therapeutic efficacy of this technique, the fluorescence of ALA-induced porphyrins can be effectively used to detect and delineate epithelial and endothelial neoplasms. In dermatology, other indications for ALA-treatment are non-tumoural applications, especially psoriasis, viral-induced diseases, or acne vulgaris. ALA is an effective compound in the diagnosis or therapy of various epithelial and endothelial neoplastic lesions.

Structural Analysis of a Metallosupramolecular Polyelectrolyte-Amphiphile Complex at the Air/Water Interface

A detailed analysis of a metallosupramolecular coordination polyelectrolyte-amphiphile complex (PAC) at the air/water interface is presented based on Langmuir isotherm measurements, Brewster angle microscopy as well as X-ray reflectance and diffraction measurements. The PAC is prepared in solution by metal-ion coordination of Fe(OAc)2 and 1,4-bis(2,2':6',2"-terpyridin-4'-yl)benzene followed by self-assembly with dihexadecyl phosphate (DHP). The spreading of the PAC at the air/water interface results in a Langmuir film with a stratified architecture, such that DHP forms a monolayer on the water surface, while the metallosupramolecular coordination polyelectrolyte (MEPE) is immersed in the aqueous subphase. Electrostatic interactions of MEPE and DHP force the alkyl chains into an upright, hexagonal lattice even at low surface pressures. This work illustrates how supramolecular, colloidal, and surface chemistry can be combined to create complex architectures with tailored characteristics that may not be accessible through self-organization in the liquid phase.

Successful treatment of discoid lupus erythematosus with argon laser

Vascular lesions with telangiectasias on visible areas, such as the face, are common in discoid lupus erythematosus (DLE); however, an efficient management of these skin lesions can sometimes be difficult. Since argon laser light is able to specifically coagulate vascular structures, it has been used in the treatment of various vascular skin malformations. Therefore, we addressed the issue whether argon laser treatment could be a therapeutic alternative for this disease. Here, we report on a patient with DLE, who suffered from long-standing erythematous, telangiectatic plaques on the face refractory to standard regimens of therapy. After 2 laser applications, a significant improvement was observed and after 5 sessions of argon laser therapy the treated skin lesions had completely resolved with an excellent cosmetic result. The patient tolerated the laser treatment well without any short-term side effects. These data indicate that argon laser therapy might be a powerful alternative approach in the treatment of vascular skin lesions of DLE.

Phototesting in Lupus Erythematosus Tumidus—Review of 60 Patients¶

Photosensitivity is an important characteristic feature of several forms of lupus erythematosus (LE), and induction of skin lesions by UV-A and UV-B irradiation has been proved to be an optimal model for evaluating light sensitivity in patients with this disease. Because lupus erythematosus tumidus (LET) has rarely been documented in the literature and is often difficult to differentiate from other photodermatoses such as polymorphous light eruption, we performed photoprovocation tests in 60 patients with LET according to a standardized protocol. Areas of uninvolved skin on the upper back were irradiated with single doses of UV-A (100 J/cm2) and/or UV-B (1.5 minimal erythema dose) daily for three consecutive days. Interestingly, patients with LET are more photosensitive than those with subacute cutaneous lupus erythematosus, and in our study experimental phototesting revealed characteristic skin lesions in 43 patients (72%). Because of the latency period in developing positive phototest reactions, it might be difficult for these patients to link sun exposure with their skin lesions. Furthermore, our data revealed a positive correlation of antinuclear antibodies and positive provocative phototest reactions in these patients as seen for other forms of LE. In conclusion, the high incidence of positive phototest reactions in correlation with the clinical findings, history of photosensitivity and antinuclear antibodies enable the classification of LET as the most photosensitive type of LE.

[Progressive cicatricial psoriatic alopecia in AIDS]

Scarring alopecia is a rare complication of scalp psoriasis which in most cases occurs in areas of long-standing lesions. A HIV-positive 35 year-old Moroccan patient (CDC C3) developed scalp psoriasis with scarring alopecia within five weeks. Topical antipsoriatic therapy resulted in alleviation of psoriatic lesions and stopped the progression of the alopecia. This case report suggests potential pathogenic links between scalp psoriasis, scarring alopecia, and HIV-infection. In addition, early and efficient antipsoriatic treatment is recommended to prevent the disfiguring complication of scarring alopecia.

[Rare cutaneous manifestaions of lupus erythematosus. A clinical overview]

Lupus erythematosus (LE) is a disease with a wide spectrum of cutaneous and systemic manifestations and has been the subject of many studies over several decades. Clinical features of patients with LE show a great variation, and for this reason it is difficult to develop a unifying concept of this disease. Consequently, this has led to the identification of subsets which have been defined by constellations of clinical and photobiological features, histological changes as well as laboratory abnormalities. Besides the characteristic classical forms such as systemic LE (SLE), subacute cutaneous LE (SCLE), and discoid LE (DLE), there are uncommon variants of LE which often lead to diagnostic difficulties. Bullous LE (BLE) and urticarial vasculitis are listed as characteristic but non-specific manifestations of systemic LE. LE tumidus (LET), LE hypertrophic/verrucous (LEHV), chilblain LE, and LE profundus (LEP) are uncommon subtypes of chronic cutaneous LE. Annular erythema and papulonodular mucinosis are further uncommon cutaneous manifestations of LE. This clinical review summarizes the typical features of the uncommon forms of LE in order to improve clinical diagnostic precision and to achieve a better differentiation of the subtypes.

Treatment of nonmelanotic hyperpigmentation with the Q-switched ruby laser

Hyperpigmentation of the skin is often refractory to conventional therapies, but has significant cosmetic implications if located on visible areas. Because laser systems are capable of removing pigment deposits caused by selective photothermolysis, we addressed the issue of whether the Q-switched ruby laser could be a useful alternative in the treatment of nonmelanotic hyperpigmented skin lesions. We report the successful treatment of a patient with hyperpigmentation caused by iatrogenic human herpesvirus 8-associated Kaposi's sarcoma and a patient with hyperpigmentation caused by long-term antimalarial therapy for cutaneous lupus erythematosus. In both patients, clinical lightening of the darkly pigmented lesions was seen after a single treatment, and a significant improvement was observed after 3 laser applications. The patients tolerated the laser therapy well without any short-term side effects and did not experience either scarring or considerable textural skin changes. Histologic examination was performed before and after laser treatment to confirm the reduction of the pigment deposits. Our data indicate that treatment of nonmelanotic skin hyperpigmentation with the Q-switched ruby laser might be a safe and powerful therapeutic method.

Lupus erythematosus tumidus--a neglected subset of cutaneous Lupus erythematosus: report of 40 cases

BACKGROUND

Lupus erythematosus tumidus (LET) is characterized clinically by erythematous, succulent, edematous, nonscarring plaques in sun-exposed areas. Results of histological examination show perivascular and periadnexal lymphocytic infiltration and interstitial mucin deposition. The main differential diagnoses are polymorphous light eruption, Jessner's lymphocytic infiltration of the skin, reticular erythematous mucinosis, and pseudolymphoma. Since its first description in 1930, LET has been documented rarely in the literature, and its clinical importance has not been fully appreciated.

OBSERVATIONS

We characterized 40 patients with clinical and histological features of LET observed at our department from 1984 through 1998. The onset of the disease clustered in summer because of sun exposure, and 28 (70%) of the patients showed a remarkable photosensitivity confirmed by results of provocative phototesting. A complete resolution of the skin lesions was seen after systemic therapy with antimalarials and, in some cases, with local corticosteroids or spontaneously without any treatment. In 4 (10%) of the patients, antinuclear antibodies were detected; however, there was no evidence of underlying systemic involvement in any of the patients.

CONCLUSIONS

Our data constitute the largest number of patients with LET collected until now. The clinical picture, extreme photosensitivity, histological findings, and effective treatment with antimalarials are so characteristic that LET should be considered as a separate entity and differentiated from other variants of cutaneous LE. Arch Dermatol. 2000;136:1033-1041

Effects of benzoyl peroxide on lipogenesis in sebaceous glands using an animal model

BACKGROUND

Benzoyl peroxide is the most widely used topical agent for acne since the 1960s. Concomitant treatment of benzoyl peroxide with oral, or topical antibiotics diminishes the multiplication of antibiotic-resistant strains of Propionibacteria acnes. Besides being antibacterial, the chemical also functions as a peeling agent, has comedolytic activity, reduces free fatty acid levels, and is touted to be sebosuppressive.

OBJECTIVE

The purpose was to determine the ability of topically applied benzoyl peroxide to suppress lipogenesis of the sebaceous glands.

METHODS

The data were obtained employing an animal model for human sebaceous glands, namely, the flank organs of female golden Syrian hamsters.

RESULTS

Our results reveal no inhibition of lipogenesis in sebaceous glands by topical application of benzoyl peroxide.

CONCLUSION

Despite many functions beneficial in acne therapy, benzoyl peroxide does not possess sebosuppressive capabilities. With the advent of water-soluble organic peroxides revealing similar antimicrobial activity to benzoyl peroxide, all therapeutic parameters (save for sebosuppression) will need to be assessed to weigh the benefits of these second-generation acne-fighting peroxides.

Up-regulation of macrophage inflammatory protein-3 alpha/CCL20 and CC chemokine receptor 6 in psoriasis

Autoimmunity plays a key role in the immunopathogenesis of psoriasis; however, little is known about the recruitment of pathogenic cells to skin lesions. We report here that the CC chemokine, macrophage inflammatory protein-3 alpha, recently renamed CCL20, and its receptor CCR6 are markedly up-regulated in psoriasis. CCL20-expressing keratinocytes colocalize with skin-infiltrating T cells in lesional psoriatic skin. PBMCs derived from psoriatic patients show significantly increased CCR6 mRNA levels. Moreover, skin-homing CLA+ memory T cells express high levels of surface CCR6. Furthermore, the expression of CCR6 mRNA is 100- to 1000-fold higher on sorted CLA+ memory T cells than other chemokine receptors, including CXCR1, CXCR2, CXCR3, CCR2, CCR3, and CCR5. In vitro, CCL20 attracted skin-homing CLA+ T cells of both normal and psoriatic donors; however, psoriatic lymphocytes responded to lower concentrations of chemokine and showed higher chemotactic responses. Using ELISA as well as real-time quantitative PCR, we show that cultured primary keratinocytes, dermal fibroblasts, and dermal microvascular endothelial and dendritic cells are major sources of CCL20, and that the expression of this chemokine can be induced by proinflammatory mediators such as TNF-alpha/IL-1 beta, CD40 ligand, IFN-gamma, or IL-17. Taken together, these findings strongly suggest that CCL20/CCR6 may play a role in the recruitment of T cells to lesional psoriatic skin.