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Notes: Summary Atopic eczema (AE) is a common skin disorder. Eczematous lesions showing macroscopic, microscopic and immunopathological resemblance to lesional AE can be induced by aeroallergens by epicutaneous testing (atopy patch test, APT). Altered epidermal barrier function, as determined by transepidermal water loss (TEWL), is a typical feature of patients with AE. The present investigation was performed to define the differences in the epidermal barrier function between positive APT reactions to aeroallergens and positive patch test reactions to contact allergens in AE patients. Allergen extracts from grass pollen, birch pollen, cat dander and house dust mite (Dermatophagoides pteronyssinus) were applied in large Finn chambers on Scanpor for 48h on the clinically unaffected and untreated skin of the back, in 11 patients with AE. The same procedure was done with 27 contact allergens of a standard test battery. Test reactions were read and TEWL was measured after 48 and 72h. Eight of the 11 patients developed positive APT reactions toD. pteronyssinus, two to cat dander and one to birch pollen. Seven of the 11 patients showed positive patch test reactions to nickel sulphate, two to potassium dichromate, one to thiuram-mix and one to paraphenylenediamine. Vehicle controls were negative. The TEWL of the positive APT reactions was significantly higher, both after 48 h (mean ± standard deviation 10·0±6·5 g/m2h) and after 72 h (9·7±5·4g/m2h) as compared with the control site (48/72h: 4·4±1.5/4·1±1·4 g/m2h) (P〈0·01). In contrast, TEWL of the positive patch test reactions to contact allergens (48/72h; 5·4±2·2/5·4±1·9g/m2h) was similar to that of the control site (48/72 h: 5·2±2·1/5·0± 1·8g/m2h) (not significant). The relative TEWL at 48 h and 72 h, expressed as the ratio between the positive patch test and the control site, was significantly higher in the positive APT reactions (48/72 h: 218·8±80·4%/232·0±85·9%) compared with positive patch test reactions to contact allergens (48/72 h: 102·1±12·0%/107·1±9·5%) (P〈0·01). It is concluded that the epidermal barrier function in AE patients is altered only in positive APT reactions, in contrast to positive patch test reactions to contact allergens. As a consequence of this aeroallergen-induced altered epidermal barrier function, further allergens can more easily penetrate the skin, inducing a vicious circle and perpetuating the eczematous lesions.

Notes: A 51-year-old white male suffering from metastatic malignant melanoma of the skin presented with lymph node metastases and paraneoplastic retinopathy 4 years after resection of the primary tumour. There were no cerebral metastases. Ocular symptoms consisting of night blindness and sensations of ‘shimmering lights’ persisted after total resection of the inguinal lymph node metastases and administration of dacarbazine and prednisone. Perimetry of both eyes was abnormal with concentric restriction. Electroretinography showed significantly reduced amplitudes in both eyes. Only 11 patients with melanoma-associated retinopathy (MAR) have been described. High titres of autoantibodies against whole retina extract were detected by enzyme-linked immunosorbent assay (ELISA) reactions. Indirect immunohistochemistry showed strong autoantibody activity against retinal bipolar cells.

Notes: Glycoprotein Ilb-IIIa (integrin alpha lib beta3) is an adhesive receptor involved in platelet aggregation and adhesion to the extracellular matrix. Previous.studies showed the presence of IIb-IIIa-like glycoproteins on cells of melanoma cell lines and on cells of lymph node metastases. This study evaluates the presence of glycoprotein IIb-IIIa subunits on cells of primary cutaneous malignant melanomas wilh (n= 4) and without (n= 9) metastases over a period of 6 years and on naevus cells (n= 4). Monoclonal antibodies directed against the subunits of the glycoprotein IIb-IIIa receptor were used on paraffin-embedded sections and evaluated by means of immuno-histochemistry. The giycoprotein lib subunit was exclusively present on cells of metastatic melanomas. It was not found on non-metastatic melanomas or benign melanocytes. These data favour the role of the integrin receptor glycoprotein IIb-IIIa in the metastatic behaviour of malignant melanomas.

Notes: Summary In a subgroup of patients with atopic eczema (AE), eczematous skin lesions can he induced by epicutaneous testing with aeroallergens (the atopy patch test: APT). An increased frequency of positive APT has been found in AK patients showing a predictive lesional pattern affecting air-exposed skin areas. This study investigates the dose-response ofthe APT in two dilTerent patient groups with AE. Petrolatum preparations of house dust mite, cat dander and grass pollen allergens in four concentrations (500–10,000) protein nitrogen imits) were tested epicutaneously in 57 patients with AE. who were prospectively divided in two groups according to whether their AE pattern was with (group I) or without (group II) a predictive distribution. Sixty-nine per cent of patients in group I. and 39% in group II. had positive APT reactions (P = 0.02). The reactions in group I were elicitable with lower allergen concentrations (P = 0.03). A clinically recognizable subgroup of patients with AE showed increased cutaneous sensitivity to aeroallergens.

Notes: Summary The clinical and histopathological classification of erythema exudativum multiforme major (EEMM), Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are difficult, due to the lack of clear-cut criteria. Based on a new clinical classification, 149 of 219 (68%) histopathological specimens, from a total of 534 patients with EEMM. SJS and TEN, have been reviewed. A comparison was made with the clinical picture, and any past history of infection or drug intake. All patients had been included in the German Registry of Severe Skin Reactions between April 1990 and December 1993. No differences could be found between the biopsies examined and the total number of histopathological specimens, concerning clinical diagnosis, gender and age. Sections from 28 of 149 specimens were not diagnostic or were too old to be properly evaluated. In nine cases, other diagnoses were proposed. One hundred and eleven of the histological slides with the diagnosis of EEMM (n= 16), SJS (n=34) and TEN (n=61), were classified as epidermal type of erythema multiforme. In these 111 slides, necrotic keratinocytes could be found, ranging from individual cells to confluent epidermal necrosis. The epidermo-dermal junction showed changes ranging from vacuolar alteration up to subepidermal blisters. The dermal infiltrate was superficial and mostly perivascular. It was sparse in SJS and TEN, and more pronounced in EEMM. Oedema in the papillary dermis was evident occasionally in all clinical groups. In 59 of 111 cases (53%), at least one eosinophil was present in the dermis. In 11 of 111 (10%), more than 10 eosinophils per field could be seen. Eosinophils were less common in the patients with the most severe forms of TEN, in whom there was detachment of more than 30% of the skin surface area. No differences in the history for drug intake, or for infection with Mycoplasma pneumoniae, herpes simplex and other organisms, could be detected between patients with or without eosinophils in their skin sections. This dermatopathological study of patients with EEMM. SJS and TEN indicates that the epidermal type of erythema multiforme is the pathological correlate for these diseases.

Notes: Background:  Worm infestations may play a role in preventing allergies. There is a lack of epidemiological information from Western countries on the association between worm infestation and eczema.Objective:  To investigate the association between worm infestation and eczema in a proper temporal sequence and under consideration of allergic sensitization.Methods:  Two surveys were performed in East German school children. Questionnaire data included the history of eczema and worm infestation and their time of onset. Specific IgE antibodies to five common aeroallergens were measured and used to define nonatopic and atopic eczema. Logistic regression analyses were performed to control for relevant confounders (age, sex, parental school education and history of allergies). In order to confirm the findings a corresponding conditional regression analysis was applied on cases and controls matched by age and sex.Results:  A total of 4169 children participated (response 75 and 76%) who were, on average, 9.2 years old (47% girls). Overall 17.0% reported a prior worm infestation (Ascaris 44%, Oxyuris 33%) and 18.1% had a history of eczema. Eczema occurred significantly less frequent in children who had a worm infestation (prior to the onset of eczema) compared with children without such a history (8.1%vs 16.5%, ORadj: 0.45, 95% CI: 0.33–0.60). The finding was confirmed by the corresponding matched case–control analysis (ORadj: 0.57, 95% CI: 0.41–0.79). Atopic eczema was affected more by a prior worm infestation (ORadj: 0.31, 95% CI: 0.18–0.56) than the nonatopic eczema (ORadj: 0.58, 95% CI: 0.40–0.84). A total of 29.1% exhibited specific IgE antibodies to at least one aeroallergen. Sensitized children gave significantly less frequent a history of worm infestation (14.2%vs 18.3%, ORadj: 0.74, 95% CI: 0.60–0.92). Stratified analysis revealed that this effect most pronounced for a sensitization to house dust mite.Conclusions:  A worm infestation is associated with a reduced frequency of subsequent eczema, especially the atopic type. Furthermore allergic sensitization, especially to house dust mite, and worm infestation are negatively associated. The data support the concept that a lack of immune-stimulation by parasitic infections contributes to the development of allergies.

Notes: Skin prick testing (SPT) is the standard method for diagnosing allergic sensitization but is to some extent performed differently in clinical centres across Europe. There would be advantages in harmonizing the standard panels of allergens used in different European countries, both for clinical purposes and for research, especially with increasing mobility within Europe and current trends in botany and agriculture. As well as improving diagnostic accuracy, this would allow better comparison of research findings in European allergy centres. We have compared the different SPT procedures operating in 29 allergy centres within the Global Allergy and Asthma European Network (GA2LEN). Standard SPT is performed similarly in all centres, e.g. using commercial extracts, evaluation after 15–20 min exposure with positive results defined as a wheal 〉3 mm diameter. The perennial allergens included in the standard SPT panel of inhalant allergens are largely similar (e.g. cat: pricked in all centres; dog: 26 of 29 centres and Dermatophagoides pteronyssinus: 28 of 29 centres) but the choice of pollen allergens vary considerably, reflecting different exposure and sensitization rates for regional inhalant allergens. This overview may serve as reference for the practising doctor and suggests a GA2LEN Pan-European core SPT panel.