[Erythema nodosum as a reaction pattern: a broad spectrum of underlying causes]. / Erythema nodosum als reactiepatroon.

Erythema nodosum is a skin disorder that is characterised by the presence of painful erythematous nodules and plaques, mainly located on the shins. This disorder is associated with comorbidities and can be considered as an aspecific reaction pattern to a broad range of causes. However, an idiopathic variant also exists, which occurs in 22-72% of cases. Erythema nodosum is pre-eminently a skin disease which, due to its multifactorial pathogenesis, occurs in a wider field than dermatology alone. Therefore, knowledge of this disorder is important for all practicing physicians. To illustrate this we describe three patients with erythema nodosum attributable to different causes.

[Focal epithelial hyperplasia of the oral mucosa. A unique manifestation of human papillomavirus]. / Focale epitheliale hyperplasie van het mondslijmvlies. Een unieke manifestatie van het humaanpapillomavirus.

A 34-year old Creole woman appeared at the dermatology department with white-pink spots on the oral mucosa, which had been there for some time. Histology showed lesions characteristic of focal epithelial hyperplasia. The patient was treated with a CO2 laser. Focal epithelial hyperplasia is a rare benign lesion and is caused by human papillomavirus subtypes 13 or 32; it only appears on the oral mucosa.

[Protection from sunlight, particularly for children]. / Bescherming tegen zonlicht, in het bijzonder bij kinderen.

Excessive exposure to ultraviolet radiation (UVR) in childhood has been recognized as an extrinsic risk factor for the development of skin cancer later in life. The risk of squamous cell carcinoma is clearly related to the lifetime accumulated UVR dose, while the risk of melanoma and basal cell carcinoma is increased by intermittent UVR exposure, which is frequently responsible for sunburn. Besides UVR exposure, several intrinsic factors increase the risk of skin cancer, especially the risk of melanoma, such as skin type, the number of normal and dysplastic melanocytic naevi and family history. Responsible sun behaviour in childhood is most important to prevent skin cancer: stay in the shade, especially between 12:00 and 3:00 p.m., wear protective clothing, including a hat and sunglasses, try to build-up natural adaptation of the skin to UVR and apply a sunscreen to UVR exposed skin. There are strong indications that the possible preventive effect of sunscreens on the development of skin cancer is abolished in case of prolonged and intensive UVR exposure, because of a false feeling of safety. The most important measure to prevent the development of melanomas and basal cell carcinomas is probably the prevention of sunburn in childhood.

Granuloma gluteale infantum: a case report.

Granuloma gluteale infantum is a benign disorder with the clinical appearance of "granulomatous" nodules involving the diaper area. It is an uncommon disorder considered a complication of primary irritant diaper dermatitis. A 6-month-old boy with reddish-purple oval nodules located on the right inguinal fold and right buttock diagnosed as granuloma gluteale infantum is presented. A contributing factor in our patient could be a primary irritant dermatitis or a preexisting candidial infection. The name granuloma gluteale infantum is a misnomer since no granulomas are found in these lesions.

Dystrophic psoriatic fingernails treated with 1% 5-fluorouracil in a nail penetration-enhancing vehicle: a double-blind study.

BACKGROUND: Topically applied nail therapeutics need to permeate the nail plate to reach the nail bed or nail matrix and exert their potential beneficial effect at these locations to obtain a therapeutic benefit. So far only topically applied 5-fluorouracil on affected nails of psoriatic patients has been shown to produce a notable clearance. Vehicle formulations enhancing nail permeation processes are thought to increase the concentration of the active agent and therefore therapeutic efficacy, possibly enabling the use of a low concentration of the active agent thereby lowering the incidence of adverse effects. OBJECTIVE: This study was designed to verify whether a recently developed nail penetration enhancer in a lotion formulation, Belanyx((R)) (urea, propylene glycol), improves the efficacy of a low concentration of 5-fluorouracil (1%) in psoriatic fingernail lesions. METHODS: In a randomised, double-blind, left-right study the efficacy of 1% 5-fluorouracil in the Belanyx vehicle was compared to the vehicle preparation Belanyx in dystrophic fingernails of 57 psoriatic patients. Both preparations were applied in a once daily regimen for 12 weeks. Responses and adverse effects of one selected target nail were recorded at screening, at baseline and at weeks 2, 4, 8 and 12 of treatment with a final assessment at week 16: 4 weeks after the end of treatment. As parameter of efficacy was chosen the total nail area severity (NAS) score, consisting of the separate parameters nail pitting area, number of nail pits, subungual keratosis, onycholysis, oil spots and the various scores of overall improvement. RESULTS: The efficacy of 1% 5-fluorouracil in lotion and that of the vehicle in suppressing the parameters of dystrophy were shown to be similar at the end of treatment (p = 0.063) or follow-up (p = 0.130). Both preparations produced statistically significant improvements (p

Diagnosis and treatment of pustular disorders in the neonate.

The diagnosis of a pustular dermatosis occurring during the first months of life is usually based on clinical findings. However, some cases may require simple investigations including microscopic examination of pustular content, cultures, and skin biopsies. The main benign transient neonatal types of pustulosis include erythema toxicum neonatorum, infantile acropustulosis, transient neonatal pustular melanosis, and neonatal acne. The most common causes of infectious pustular skin lesions include bacterial infections, which may be initially localized (Staphylococcus aureus) or septicemic (with Listeria monocytogenes as the leading causitive agent); viral infections (herpes simplex, varicella-zoster, and cytomegalovirus infections); fungal infections (candidiasis); or parasitic disorders (scabies). The main objective of this article is to propose a systematic approach to pustular eruptions in the neonate. The need for investigating every neonate with pustules for an infectious disease is emphasized. The Tzanck smear, the Gram's stain, and a potassium hydroxide preparation are the most important quick diagnostic tests. The Tzanck smear is a very easy, rapid, and sensitive test for detection of a herpetic infection (multinucleated giant cells) as well as noninfectious pustular eruptions (eosinophils, neutrophils). Therefore the Tzanck smear should be the first test performed. Moreover, a Gram's stain and potassium hydroxide preparation should be performed in cases of neonatal pustular disorders to detect bacterial and fungal infections. The goal of this diagnostic approach is to spare a healthy neonate with a benign transient condition an invasive evaluation for sepsis, potentially harmful antibiotic therapy, and prolonged hospitalization, with its own inherent morbidity.

Long-term ultraviolet B-induced impairment of Langerhans cell function: an immunoelectron microscopic study.

The influence of low-dose, long-term ultraviolet B (UVB) light exposure on HLA class II-positive human epidermal Langerhans cells (LC) was studied using a sensitive immunoelectron microscopic technique for the ultrastructural assessment of HLA class II expression on LC and for quantification of these cells in situ. Six healthy Caucasian volunteers participated in the experiments and received thrice weekly UVB treatments for 4 weeks. The initial dose ranged from 30 to 50 mJ/cm2 and the total dose from 600 to 3500 mJ/cm2, depending on skin type. Suction blisters and biopsies were obtained before the start of the UVB protocol and 48 h after the last UVB irradiation, and processed for the mixed epidermal cell-lymphocyte reaction (MECLR) and electronmicroscopy, respectively. The MECLR was used as a measure of the immune response. The distribution of HLA class II molecules on LC was studied by incubating ultrathin cryosections of human skin tissue with an anti-HLA class II MoAb that was conjugated to 10 nm colloidal gold. Furthermore, the number of LC was assessed ultrastructurally, when they could be recognized by their unique cytoplasmic organelle, the Birbeck granule (BG). The UVB protocol that was employed caused a marked suppression of the MECLR responses. This UVB-induced reduction of the immune response was not paralleled by changes in HLA class II expression on LC, nor in the number of epidermal LC. These findings are further support for our hypothesis that UVB-induced immune suppression in the skin is not due to a depletion of local LC.

Determination of the photoprotective efficacy of a topical sunscreen against UVB-induced DNA damage in human epidermis.

The ability of a chemical sunscreen with a sun protection factor of ten to protect human skin in situ against UVB-induced DNA damage (cyclobutyl thymine dimers) was evaluated. Biopsies were taken from the left buttock of ten human volunteers prior to UVB (280-315 nm) exposure. Subsequently, a sunscreen (n = 6) or vehicle (n = 4) was applied to a delineated area on the right buttock. After a period of 30 min, the entire buttock area was irradiated in a UVB cabin with one minimal erythema dose. Immediately after irradiation, biopsy specimens were obtained from the UVB-exposed sunscreen- or vehicle-treated right buttock and from the non-treated UVB-exposed left buttock. Dimers were assayed in skin sections by immunofluorescence microscopy with a monoclonal antibody against the cyclobutyl thymine dimer. The dimer-specific fluorescence from the epidermal cell nuclei, identified by counterstaining with propidium iodide, was quantified through computer-mediated image processing and analysis in skin sections of one sunscreen-treated and one vehicle-treated volunteer. After a single dose of UVB, significant dimer-specific nuclear fluorescence was observed and measured in the non-treated biopsy specimens. No nuclear fluorescence was observed and very little could be measured in the non-UVB-exposed skin and in the sunscreen-treated UVB-exposed skin respectively, indicating that the sunscreen offered good protection against the induction of cyclobutyl thymine dimers by UVB. This visual scoring is in general semiquantitative, but quantification through computer-mediated image processing was performed in one case for sunscreen-treated skin and in one case for vehicle-treated skin. Both assessments resulted in similar conclusions.(ABSTRACT TRUNCATED AT 250 WORDS)

Minimising the risks of PUVA treatment.

Psoralen photochemotherapy (PUVA) is a combination of orally administered psoralen and long wave ultraviolet-A radiation (UVA), and is one of the most effective forms of therapy for psoriasis. The unwanted effects of PUVA therapy can be divided into short and long term adverse effects. The short term adverse effects include erythema, pruritus, nausea and headache. While short term adverse effects are limited and reversible after discontinuation of treatment, potential long term adverse effects such as chronic actinic skin damage, dyskeratotic and precancerous skin conditions, nonmelanoma skin cancer, immunological alterations and cataract formation are of greater concern. Long term risks associated with PUVA therapy can be minimised by several measures. Careful patient selection is mandatory; for example, patients with chronic actinic damage and a history of skin cancer may bear a higher risk for the development of new cancers, and previous arsenic intake and ionising radiation also increase the risk of nonmelanoma skin cancers. Certain drug combinations make it possible to lower the UVA dose, which is important because of the dose-dependent increase in the incidence of squamous cell carcinomas in patients treated with PUVA. It has been demonstrated that 200 treatments or a total UVA dose of 1200 J/cm2 seems to be the threshold for development of nonmelanoma skin cancer. Shielding male genitalia during PUVA treatment is essential because of the increased risk of genital squamous cell carcinomas. Yearly dermatological examination to detect skin cancer at an early stage is highly advisable. Sunscreen use, protective clothing and avoidance of sun exposure reduce the uncontrolled dose of solar UV radiation. Other psoralens with a less carcinogenic potential can be used. UVA-opaque sunglasses during the entire period of increased photosensitivity after psoralen ingestion help avoid cataract formation. Assignment to PUVA ought to be based on the risk-benefit ratio for the individual patient and should be limited to those who can be monitored and controlled by informed, competent and conscientious physicians.

PUVA keratosis. A clinical and histopathologic entity associated with an increased risk of nonmelanoma skin cancer.

BACKGROUND: Various types of hyperkeratotic lesions can be observed in patients with psoriasis treated with PUVA. Clinically it can be difficult to classify them and to differentiate benign from malignant hyperkeratotic lesions. Recently, we introduced the term PUVA keratosis, which we regard as a distinct entity. OBJECTIVE: The purpose of the study was to describe in more detail the clinical and histopathologic features of PUVA keratoses and to investigate a possible relation with nonmelanoma skin cancer. METHODS: A group of 13 psoriasis patients with PUVA keratoses was studied and compared with 247 psoriasis patients without these keratoses, who had also received long-term therapy with PUVA. RESULTS: The presence of PUVA keratoses was associated with an increased risk of nonmelanoma skin cancer. The estimated relative risk for skin cancer in patients with PUVA keratoses, adjusted for age, sex, and UVA dose, as compared with psoriasis patients without these keratoses, who had also received long-term PUVA treatment, was 6.5 (95% confidence interval, 1.3 to 32.1). Squamous cell carcinomas contributed the most to this increased risk. CONCLUSION: PUVA keratoses are associated with an increased risk of nonmelanoma skin cancer. Therefore careful clinical follow-up of psoriasis patients with PUVA keratoses is necessary, and cessation of PUVA treatment should be considered.

HLA class II expression on human epidermal Langerhans cells in situ: upregulation during the elicitation of allergic contact dermatitis.

An immunoelectron-microscopic technique was applied to investigate the localization of molecules that are involved in the elicitation of allergic contact dermatitis in human epidermal cells in situ. Langerhans cells in the epidermis of lesions showed a strongly increased cell surface expression of HLA class II molecules as compared with normal skin. In addition, a high number of intracellularly located HLA class II molecules were present in Langerhans cells of lesional epidermis, suggesting increased biosynthesis of these molecules during the elicitation process. In contrast, no differences in the expression of CD1a by Langerhans cells was observed between normal and lesional skin. Frequently, the Langerhans cells were found in close apposition to mononuclear cells, which also exhibited a strong cell surface HLA class II expression. The number of Birbeck granules that are characteristic intracellular Langerhans cells organelles was increased in lesional Langerhans cells as compared with normal-skin Langerhans cells, which may correlate with the activated state of lesional Langerhans cells. These Birbeck granules were always HLA class II or CD1a negative. The increased synthesis and expression of HLA class II molecules on the cell surface of Langerhans cells suggests a direct role for these HLA class II molecules in the elicitation process of allergic contact dermatitis.

Effect of topical sunscreens on the UV-radiation-induced suppression of the alloactivating capacity in human skin in vivo.

Exposure of mice or humans to solar or artificial ultraviolet radiation (UV) has been shown to induce a number of changes in the immune system that may influence their susceptibility to skin tumors. The protective effect of sunscreens on these changes is not clear. Thirty-two patients with a variety of dermatoses routinely undergoing treatment with standard UVB (n = 19) or PUVA (n = 13) therapy were studied. One of the two tested sunscreens or its vehicle was applied to the right flexor forearm immediately prior to each total-body UV exposure. Epidermal sheets were obtained by the suction-blister method from the left flexor forearm before treatment and from both flexor forearms after 4 weeks of photo- or photochemotherapy and used as stimulator epidermal cells (EC) in the mixed epidermal cell-lymphocyte reaction (MECLR). After 4 weeks of either UVB or PUVA therapy the MECLR responses on EC from both arms were markedly decreased. Neither the tested sunscreens nor their vehicles prevented the UV-induced suppression of the alloactivating capacity. The failure of sunscreens to protect against the UV-induced suppression of the alloactivating capacity could be explained in two ways. First, the energy not absorbed by the sunscreen could be sufficient to induce suppression of the alloactivating capacity. An alternative explanation could be systemic immune suppression by UV. In order to discriminate between these possibilities only the right forearms of 10 healthy volunteers, treated with a sunscreen or its vehicle, were irradiated with UVB during 4 weeks. In this manner systemic immune suppression by UVB could be excluded. This experiment resulted in a similar suppression of the MECLR responses, as induced by total body UVB irradiation, without any protection by the sunscreen. Apparently, the UV dose not absorbed by the sunscreen was capable to induce suppression of the alloactivating capacity. Our results indicate that people protected from sunburn by sunscreens may be exposed to UV for a long period of time, and thereby subject themselves to its immunosuppressive action.

Clinical evaluation of a double-blind dust-mite avoidance trial with mite-allergic rhinitic patients.

Inheritance and allergen exposure are key factors in the development and the course of atopic allergy, expressed as conjunctivitis, rhinitis, asthma or dermatitis. This study concerns the clinical significance of mite and mite-allergen avoidance measures based on intensive cleaning with acaricide (solidified benzylbenzoate) added (10 dwellings), and without biocidal activity (10 other homes) as a control in a double-blind trial with matched pairs. Twenty subjects with persisting rhinitic complaints were selected. They lived in 20 different dwellings and were all sensitized to pyroglyphid mites; 12 of them were also sensitized to stored product mites (Acari). Daily symptoms and medication score, guanine and dust exposure, total and mite-specific IgE in serum, eosinophilia in the blood and in the nasal smear, intracutaneous tests with house dust mite and storage mite extracts were compared in both pairs and groups. Acarological data, physiochemical aspects and exposure assessment are discussed in detail elsewhere. Symptom scores dropped significantly, as did the total IgE and exposure to dust and mite products in the acaricidal cleaner treatment group. After 1 year, the daily symptoms median was 47% (P = 0.025), total IgE was 38% (P = 0.0049), and exposure to dust and mite products (guanine exposure) was 53% (P = 0.0449) better or lower than in the controls. Intensive cleaning, without acaricidal treatment performed twice a year, resulted in clinical improvement in four out of 10 subjects, of whom none became free of complaints. In the Acarosan treatment group (cleaning + benzylbenzoate) eight out of 10 subjects improved, in three cases subjective symptoms disappeared.(ABSTRACT TRUNCATED AT 250 WORDS)

Analysis of the protective effect of topical sunscreens on the UVB-radiation-induced suppression of the mixed-lymphocyte reaction.

The mixed-lymphocyte reaction (MLR) was used to test the protective capacity of several sunscreens against UVB-radiation-induced suppression of the immune response. The MLR was performed using stimulator cells that had been exposed to 120 mJ/cm2 of an UVB source, whereas in simultaneous experiments a sunscreen-covered piece of quartz glass was placed in between the light source and the culture dish. The MLR response after UVB radiation was significantly decreased in comparison with the MLR response of non-radiated cells. This UV effect was partly inhibited by the tested sunscreens, whereas their vehicles alone showed hardly any effect. The protective capacity of sunscreens with similar protection factors, which were determined using the minimal erythematous dose (MED), showed a significant variation. These results suggest that the MED is not an accurate method to determine protection against UV-induced immunologic damage.