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Notes: Contact allergy to and allergic contact dermatitis from methyldibromo glutaronitrile (MDBGN) have frequently been reported. This study was initiated to help determine the optimal patch test preparation for MDBGN. In 51 patients with a doubtful or a positive patch test reaction to at least 1 of 4 test preparations with MDBGN in petrolatum at 1.0% w/w, 0.5%, 0.3% and 0.1%, a repeated open application test (ROAT) with moisturizers with and without MDBGN at 0.03% w/w was performed on the upper arms for 2 weeks. 18 of the 51 (35.3%) patients developed a positive ROAT. In all patients, there was a positive ROAT only to the moisturizer with MDBGN (P 〈 0.001). A statistically significant association was also found between the patch test reactivity (PTRL) and the outcome of the ROAT (P 〈 0.001). If only considering those with a PTRL above 0.3%, thus with negative or doubtful test reactions to 0.1% and 0.3%, there were still statistically significantly more patients with a positive ROAT to the moisturizer with MDBGN than to the moisturizer without MDBGN. The study demonstrates that patch testing with MDBGN at 0.3% and 0.1% will miss clinically relevant patch test reactions to MDBGN.

Notes: Atopy patch tests (ATPs) are believed to be a useful diagnostic procedure for atopic dermatitis (AD), aiming at the detection of delayed reactions to aeroallergens and food allergens. Our aim was to investigate immune responses to gluten and gliadin in children affected by coeliac disease by performing APTs, and to compare these data to the ones observed in AD patients. 31 children, 15 males and 16 females (mean age ± s.d. = 5,5 ± 3,8 years) affected by coeliac disease underwent APTs with gluten and gliadin. Among these, 15 children were on gluten-free diet at the moment of our examination and 3 patients were affected by AD. 83 AD children not affected by celiac disease, were used as controls. 19,4% and 12,9% of children with coeliac disease proved positive to APTs with gluten and gliadin, respectively. No difference in the frequency and intensity of APT responses were present between the patients on gluten-free diet and the children not on diet. Among AD patients 12% reacted to gluten, whereas no positive reactions to gliadin were observed. Going on these findings, the cellular-mediated reactivity to gliadin in patients with coeliac disease may show a clinical expression by positive APT reactions to gliadin. These represent a specific finding in subjects with coeliac disease when compared to AD children.

Notes: A 10-year multicentre analysis of the frequency of sensitivity to common preservatives collected in 16 centres in 11 countries has shown stable but persisting high levels of sensitivity to formaldehyde and 5-chloro-2-methyl-4-isothiazolin-3-one + 2-methyl-4-isothiazolin-3-one (MCI/MI). It has also revealed a significant increase in the level of reactivity to methyldibromoglutaronitrile (MDBGN) from 0.7% in 1991 to 3.5% in 2000. The current high level of sensitivity to MDBGN requires an urgent safety re-evaluation and risk assessment update along with consideration of immediate lowering of use concentrations, especially in leave-on products.

Notes: Propolis is an ancient remedy well known for its beneficial properties. The aim of our study was to estimate the frequency of sensitization to propolis in our pediatric patch test population. 1255 children, 583 boys and 672 girls, aged from 7 months to 12 years, were patch tested for suspected allergic contact dermatitis with our pediatric series of 30 allergens including propolis. Out of these, 37% were affected by atopic dermatitis. Among the 1255 children tested, 113 (9%), 60 boys and 53 girls reacted to propolis. In subjects reacting to propolis the dermatitis involved the face in 4% of cases, the trunk in 3%, the hands in 2,2%, and the flexural skin folds of the limbs in 1,7%. The wider and wider use of propolis in “natural products” and biocosmetics, even in the pediatric age, could explain the high frequency of positive patch test responses to propolis we observed.

Notes: The Muir–Torre syndrome (MTS) is an autosomal dominant genodermatosis characterized by the presence of sebaceous gland tumours, with or without keratoacanthomas, associated with visceral malignancies. We describe and characterize two families in which the ample phenotypic variability of MTS was evident. After clinical evaluation, the skin and visceral tumours of one member of a family with ‘classic’ MTS and one member of a family with a ‘peculiar’ MTS phenotype without sebaceous lesions, but with only multiple keratoacanthomas, were analysed for microsatellite instability (MSI) and by immunohistochemistry. Tumours of both individuals showed MSI, with a concomitant lack of MSH2 immunostaining in all evaluated skin and visceral lesions; moreover, in the proband of family 2 a constitutional mutation (C→T substitution leading to a stop codon) in the MSH2 gene was identified. We conclude that the diagnosis of MTS, which is mainly clinical, should take into account an ample phenotypic variability, which includes both cases with typical cancer aggregation in families and cases characterized by the association of visceral malignancies with multiple keratoacanthomas (without sebaceous lesions), without an apparent family history of cancer.

Notes: Background  The assessment of colours is essential for the diagnosis of malignant melanoma (MM), both for pattern analysis on dermoscopic images, and when employing semiquantitative methods.Objectives  To develop a computer program for colour assessment in MM images mimicking the human perception of lesion colours, and to compare the automatic colour evaluation with one performed by human observers.Methods  A colour palette comprising six colour groups (black, dark brown, light brown, blue–grey, red and white) was created by selecting single colour components inside melanocytic lesion images acquired by means of a digital videomicroscope, and was implemented in the image analysis program. Subsequently, colours were assessed by the computer program on 331 melanocytic lesion images composing our image database, and the results were compared with the evaluation of lesion colours performed by the clinician.Results  The black, white and blue–grey colours were more frequently found in MMs than in naevi, both by the clinicians and by the computer. In MM images we observed 4·27 ± 1·14 colours (mean ± SD) per lesion, as opposed to 3·22 ± 0·68 in naevi. The correlation between clinical and computer evaluation of the colours was very good, with a value of 0·781 for overall assessment.Conclusions  This innovative method for automatic colour evaluation, reproducing clinical assessment of melanocytic lesion colours, may provide numerical parameters to be employed for computer-aided diagnosis of MM.

Notes: Background  Ceramides produced by sphingomyelin hydrolysis activate a cycle that is followed by three different major cellular responses: downregulation of cell proliferation, induction of cell differentiation and apoptosis. In the skin, the generation of intracellular ceramide may also provide a link between an extracellular signal and the induction of the apoptosis programme for the elimination of damaged cells. Objectives We investigated the effect of ceramides capable of entering cells on cultured keratinocytes. Methods Human keratinocytes from neonatal skin were cultured in serum-free medium with or without increasing concentrations of ceramide 2 (CER-2; N-acetyl sphingosine) (5, 10, 20 and 40 µmol L−1). Proliferative effects were studied either by cell counts or by 3H-thymidine incorporation and flow cytometric analysis. Apoptosis was studied by TUNEL staining and Western blot analysis of Bcl-2 protein. Results Cell counts and DNA synthesis were reduced in a dose-dependent manner following CER-2 treatment. TUNEL staining showed CER-2-induced apoptosis at 48, 72 and 96 h. Western blot analysis showed that CER-2 induces downregulation of Bcl-2 at 24–96 h. Conclusions These results demonstrate that CER-2 inhibits cell proliferation and induces apoptosis, possibly via a Bcl-2-dependent mechanism.

Notes: The distribution and localization of several neuropeptides were investigated in the lichenified lesions of 11 patients with atopic dermatitis using indirect immunofluorescence. Substance P-positive nerve fibres were observed in most of the cases of atopic dermatitis, but not in normal controls. Somatostatin immunoreactive nerves were not found in the skin of atopic dermatitis, whereas a normal pattern of immunoreactivity could be detected in most of the healthy subjects. Neuropeptide Y-positive dendritic epidermal cells were observed in lesional skin from patients with atopic dermatitis, but not in controls. Calcitonin gene-related peptide and vasoactive intestinal polypeptide immunoreactivity in patients with atopic dermatitis did not differ from that in healthy subjects. With galanin antiserum a diffuse intracellular staining was observed in the epidermis of both atopic patients and controls, while no positive staining was found with either neurotensin or neurokinin A antibodies in either group. These findings suggest a possible involvement of some neuropeptides in the pathomechanisms of atopic dermatitis.

Notes: Background:  The atopy patch test (APT) was proposed to evaluate IgE-mediated sensitizations in patients with atopic eczema (AE).Objective:  The prevalence and agreement with clinical history and specific IgE (sIgE) of positive APT reactions was investigated in six European countries using a standardized method.Methods:  A total of 314 patients with AE in remission were tested in 12 study centers on clinically uninvolved, non-abraded back skin with 200 index of reactivity (IR)/g of house dust mite Dermatophagoides pteronyssinus, cat dander, grass, and birch pollen allergen extracts with defined major allergen contents in petrolatum. Extracts of egg white, celery and wheat flour with defined protein content were also patch tested. APT values were evaluated at 24, 48, and 72 h according to the European Task Force on Atopic Dermatitis (ETFAD) guidelines. In addition, skin-prick test (SPT) and sIgE and a detailed history on allergen-induced eczema flares were obtained.Results:  Previous eczema flares, after contact with specific allergens, were reported in 1% (celery) to 34% (D. pteronyssinus) of patients. The frequency of clear-cut positive APT reactions ranged from 39% with D. pteronyssinus to 9% with celery. All ETFAD intensities occured after 48 and 72 h. Positive SPT (16–57%) and elevated sIgE (19–59%) results were more frequent. Clear-cut positive APT with all SPT and sIgE testing negative was seen in 7% of the patients, whereas a positive APT without SPT or sIgE for the respective allergen was seen in 17% of the patients. APT, SPT and sIgE results showed significant agreement with history for grass pollen and egg white (two-sided Pr 〉 |Z| ≤ 0.01). In addition, SPT and sIgE showed significant agreement with history for the other aeroallergens. With regard to clinical history, the APT had a higher specificity (64–91% depending on the allergen) than SPT (50–85%) or sIgE (52–85%). Positive APT were associated with longer duration of eczema flares and showed regional differences. In 10 non-atopic controls, no positive APT reaction was seen.Conclusion:  Aeroallergens and food allergens are able to elicit eczematous skin reactions after epicutaneous application. As no gold standard for aeroallergen provocation in AE exists, the relevance of aeroallergens for AE flares may be evaluated by APT in addition to SPT and sIgE. The data may contribute to the international standardization of the APT.

Notes: Background: So far the issue of patch tests with mite allergens in subjects not affected by atopic dermatitis (AD) has been poorly investigated. The aim of this study was to assess the frequency and intensity of responses to atopy patch tests with Dermatophagoides in non-AD subjects, and to compare them to the ones observed in AD patients.Methods: Patch tests were performed, employing a mixture of Dermatophagoides pteronyssinus and farinae at two different concentrations (20 and 40% pet.), on 75 non-AD subjects, including 33 patients with allergic rhinitis and 42 healthy volunteers, and on 210 AD patients, as controls.Results: Positive responses to 20% mite patch tests were observed in 17 non-AD subjects (23%) and in 102 AD ones (49%). The former showed a lower intensity of the responses, with a mean score of 1.4 compared with 2.1 in atopics.Conclusions: Although positive responses to mite patch tests are also observable in subjects without AD, their frequency and intensity are significantly lower compared with AD patients.