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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:  Food atopy patch tests (APTs) are considered a useful tool for the diagnosis of food allergy. Hypersensitivity to peanuts has not been investigated by means of APTs so far.Methods:  APTs and skin prick tests (SPTs) with peanuts were performed in 136 atopic dermatitis (AD) patients. Relevance of positive and negative responses to these tests was assessed by repeated open challenges with peanuts.Results:  Nine percent of our AD patients reacted to the challenge. Positive responses to APTs were recorded in 19% of the patients, whereas in 12% positive SPTs were observed. APTs were more frequently positive in subjects with eczematous responses after challenge with respect to those with urticarial reactions. SPT reactivity proved to be higher in patients above 12 years of age, whereas APT positivity was more frequent in children under 6 years. APT sensitivity proved significantly higher than SPT sensitivity, in particular in children under 12 years of age. On the contrary, SPT specificity and positive predictive value were significantly higher with respect to those of APT in the age group of subjects under 6 years of age.Conclusions:  Our data suggest that APTs with peanuts may represent a useful integration to standard testing modalities employed for the diagnosis of peanut allergy in AD patients.

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: Using 3 different ready-to-apply patch test systems (Epiquick®= EPI; Rapid Patch Test®= RPT; TRUE TestTM= TT), 316 patients sensitive to at least one allergen were studied in order to investigate the reproducibility of these tests in comparison with the Finn Chamber ®(FC) technique. Each patient was tested with a different ready-to-use system. Each test was compared to the same allergen applied with FC to either side of the upper back. Comparisons were made using EPI, RPT, and TT in 93 (183 tests), 119 (262 tests), and 104 (242 tests) patients respectively. When a positive test result occurred on only one side of the back, the concordance was defined as negative. Similarly, doubtful reactions on either side corresponding to positive or negative results were considered as non concordant. The concordance of positive reactions was 80.9% between the EPI and the FC technique, 77.5% between the RPT and the FC technique, and 72.3% between the TT and the FC technique. The frequency of questionable (+?) and irritant reactions (IR) was about the same for the different tests. Nevertheless, when comparing the positive reactions vs +?, IR, or negative reactions in paired tests, positive results were more frequently obtained with the FC technique. Our data suggest that the standard method with FC allows a better detection of contact allergy than the new ready-to-use systems tested in this study.

Notes: Abstract Ten psoriatic plaques from different subjects were investigated by 20 MHz ultrasound B scanning. Lesions were evaluated before therapy, and after 7 and 15 days of topical treatment with anthralin. Recordings from lesional skin were compared with those from clinically non-involved contralateral skin. Images were assessed by means of a new image analysis program, allowing the conversion of the B-scan image color scale into a numerical amplitude scale, the selection and highlighting of amplitude bands, and the quantification of objects reflecting in a definite amplitude range. B-scanning evaluation of the psoriatic plaque revealed a thickening of the epidermis and dermis, the presence of parallel acoustic shadows in the dermis, and a characteristic hypo-echogenic band corresponding to the papillary dermis. Image processing allowed an exact quantification of the progressive reduction in thickness of the epidermis and dermis and of the hypo-echogenic band observed at skin sites which had been treated with topical substances. Thus, the echographic method with image analysis allows the evaluation of three different parameters of response to topical treatment of psoriatic skin.

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: 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: We have described 100 subjects sensitized to textile dyes. Of these, 16 had clinically been suspected of having a textile dermatitis from among 1145 patients referred for patch testing. 41 patients were identified from among 861 consecutive subjects tested with the GIRDCA (Italian Research Group on Contact and Environmental Dermatitis) standard series supplemented with 4 disperse dyes (Disperse Blue 124, Disperse Red I, Disperse Yellow 3. Disperse Orange 3), The remaining 43 patients were identified from among 746 subjects tested with the GCRDCA standard series, supplemented with the 4 disperse dyes mentioned above and a further series of 12 other textile dyes, The clinical picture was extremely variable: most patients had a typical eczematous dermatitis, but we also observed persistent erythematous-wheal-type reaction. a transient urticarial dermatitis and an erythema-multiforme-like eruption Among these textile dyes, Disperse Blue 124 caused most reactions. With the addition of the 4 disperse dyes to the GIRDCA standard series, we identified 4.8% sensitized 10 textile dyes. a much higher figure than the 1.4% observed among patients being patch tested on the basis of their history and the clinical findings; the addition of a further 12 textile dyes to the series further increased the detection rate to 5.8%. We stress the importance of routinely patch testing with textile dyes, which can help to elucidate the cause of certain kinds of atypical dermatitis