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Notes: Summary We report the first case, to the best of our knowledge, of a woman suffering from cystic echinococcosis of the liver, who consequently developed urticaria and acute generalized exanthematous pustolosis (AGEP). Serum immunoglobulin (Ig)E and IgG4 specific to Echinococcus granulosus antigens were detected by immunoblotting. Furthermore, the intracellular cytokine analysis revealed a prevalent T-helper 2 polarization. It can be reasoned that, while the presence of IgE specific to various E. granulosus allergens may be responsible for the chronic urticarial manifestations, the detection of IgG4 specific for E. granulosus antigens, forming immunocomplexes, may be related to the development of the AGEP.

Notes: Background: Although corn is often cited as an allergenic food, very few studies have been devoted to the identification of corn allergens and corn allergy has been rarely confirmed by double-blind, placebo-controlled food challenge (DBPCFC). Recently, Pastorello et al. (1) identified some salt-soluble IgE-binding proteins of corn flour as potential allergens. One of these, corresponding to corn Lipid Transfer Protein (LTP), appeared to be the major one. The aim of this study was to verify the clinical significance of the skin prick test (SPT) and CAP-FEIA CAP-System IgE fluozoenzyme immunosorbent assay (Pharmacia Diagnostic, Uppsala, Sweden) positivities to corn and to identify the presence of IgE-binding proteins in the corn flour salt-insoluble protein fractions (comprising up to 96% of the total protein) using sera of patients with DBPCFC-documented food allergy to corn. In addition the effect of cooking and proteolytic digestion on the corn allergens was investigated. Methods: Sixteen subjects with SPT and CAP-FEIA positivities to corn flour were examined. Only six of them complained of suffering from urticaria and/or other symptoms after ingestion of corn-based foods. The patients were food challenged with cooked corn flour (polenta). IgE-binding proteins were detected by immunoblotting. The digestibility of the IgE-binding proteins was examined during a pepsin attack followed by a pancreatin digestion performed on a cooked corn flour sample. Results: Oral challenge was positive only for six patients with symptoms after ingestion of corn. A 50 kDa protein, belonging to the corn Reduced Soluble Protein (RSP) fraction was recognized by the serum IgE of all the DBPCFC-positive subjects and resulted to be resistant to both heating and peptic/pancreatic digestion. SPT with the purified RSP fraction gave positive results for all of the DBPCFC-positive patients examined. Conclusions: SPT and CAP-FEIA positivities to corn flour had no clinical significance for most of the patients and food allergy to corn has to be proved by DBPCFC. A salt-unextractable protein of 50 kDa, belonging to the RSP fraction, represents a potential allergen in food hypersensitivity to corn because of its stability to cooking and digestion.

Notes: The authors report a case of erythema multiforme in a 32-year-old woman who was also taking oral terbinafine for an onychomycosis. The patient data analysis showed serological positivity for cytomegalovirus (IgM and IgG) and hepatitis C virus and serological titre of antinuclear antibody was elevated. After a brief review of the literature the authors propose the possibility of virus–drug interaction as a model of adverse drug reactions.

Notes: Background The involvement of IgE-mediated hypersensitivity reactions in the genesis of gastrointestinal symptoms after ingestion of foods containing wheat has been rarely reported.Objective To detect IgE specifically binding to wheat proteins in the sera of atopic and non-atopic patients suffering from gastrointestinal symptoms after ingestion of wheat and to evaluate the reliability of skin prick test and CAP in the diagnosis of food allergy to wheat.Methods The sera of patients (10 atopic and 10 non-atopic) previously diagnosed as suffering from irritable bowel syndrome and complaining of symptoms after wheat ingestion were analysed by immunoblotting for IgE binding to water/salt-soluble and insoluble wheat flour proteins.Results All the atopic patients and only one of the non-atopic patients were positive to wheat CAP. For the patients tested, skin prick test was positive for all the atopic patients and for only one of the non-atopic patients. However, immunoblotting experiments showed the presence of specific IgE to wheat proteins in all the patients. Ten out of 11 of the wheat CAP-positive patients had IgE binding to a soluble 16-kDa band, but the same band was recognized, in a slighter way, by only two out of nine of the wheat CAP-negative patients. Moreover, although almost all of the patients were negative in CAP testing with gluten, 19 out of 20 recognized protein bands belonging to the prolamin fraction.Conclusions For the atopic patients the positivity to skin prick test and CAP to wheat was in accordance with the immunoblotting results and a food allergy to wheat could be diagnosed. In these patients a major allergen was a 16-kDa band corresponding to members of the cereal α-amylase/trypsin inhibitors protein family, the major allergens involved in baker's asthma. In the non-atopic patients the positive immunoblotting results contrasted with the responses of the allergologic tests, indicating that the allergenic wheat protein preparations currently used are of limited value in detecting specific IgE to wheat and that the fraction of irritable bowel syndrome (IBS) patients with food allergy may be larger than believed.

Notes: The aim of the present paper is to evaluate whether increasing environmental exposure increases the frequency of the positive prick and patch test reactions to certain chlorinated platinum salts in patients with dermatitis and urticaria. 800 consecutive subjects with contact dermatitis (n=749) and urticaria (n=51) were variously patch and prick tested with 30 haptens of a standard series, with aqueous solutions of, respectively, hexachloroplatinic acid (H2[PtCl6]), potassium tetrachloroplatinate (K2[PtCl4]), sodium hexachloroplatinate (Na2[PtCl6]), iridium chloride (IrCl3), rhodium chloride (RhCl3) and palladium chloride (PdCl2), and with 16 common inhalants. 153 workers, variably exposed in a platinum refinery, were patch and prick tested only with solutions containing platinum-group elements at various concentrations and with 16 common inhalants. Platinum-group elements did not elicit positive patch or prick test reactions in non-occupationally exposed subjects. In contrast, in exposed workers, positive patch test reactions at day 2 and at 25 min, respectively, were found in 2 subjects with hand dermatitis and in 2 with urticaria and asthma. 22 out of the 153 workers, 18 of whom had rhinitis, asthma, and urticaria, gave positive prick test reactions to 1 or more salts. Furthermore, on patch and prick testing, 4 cross-reactions between platinum, palladium, iridium and rhodium were demonstrated. In conclusion, the test results demonstrate that the present concentration in the environment does not increase the incidence of reactions to platinum salts in patients with dermatitis and/or urticaria. However, if the average level of environmental platinum exposure approaches those existing in industrial settings in the future, we are going to observe more frequent health effects.

Notes: The expression and the distribution of metallothioneins (MT)-I and II isoforms were evaluated in 5 healthy volunteers and in 16 subjects with positive patch test reactions to various compounds. Skin specimens taken both from the healthy skin of the back and at positive patch test sites (at 48 h), were treated using a 3-step indirect immunoperoxidase procedure with a mouse monoclonal IgG1 antibody reactive against I and II isoforms of human, rat and horse MT. MT were expressed in the basal layer of the healthy skin of both controls and sensitive subjects, without any significant difference. At positive patch test sites, there was an overexpression of MT in basal and suprabasal layers of the epidermis. Overexpression of MT, related to the degree of the inflammatory reactions elicited by the penetrating compounds was observed in the dermis. The cells expressing MT in the dermis were mostly T lymphocytes and cells with dendritic morphology which positively stained in part for CD34 and in part for XIIIa markers and negatively for KP1, S100 and HLA-DR. Taken together, these results seem to indicate that MT represent a constitutive mechanism of defence expressed by different types of cells in the skin, which is triggered by contact with both metallic and non-metallic compounds. The biological significance of MT in the skin remains to be elucidated. Our preliminary findings do not permit evaluation of whether these nearly ubiquitous proteins exert their cytoprotective effects in the skin acting simultaneously as antioxidant, metal binding or zinc suppliers, or if they display these activities mainly depending on the nature of the penetrating substances.

Notes: We evaluated the role of pre-existing dermatitis in the response to irritants by patch testing the skin of 40 healthy volunteers and the uninvolved skin of 480 subjects for 2 days. These latter were affected by active atopic dermatitis, psoriasis, eczema with positive and negative patch test reactions, urticaria and generalized pruritus. A first panel containing 15 µL of aq. solutions of disodium laureth sulfosuccinate (NaLSS) 5% and 10%, potassium cocoate (KCC) 5%, potassium oleate (KOL) 5%, zinc coleth sulphate (ZnCS) 5%, sodium mireth sulphate (NaMS) 5%, sodium cocoamphoacetate (NaCCAA) 3% and 5%, was simultaneously applied to 1 site on the upper back. The results, scored by visual assessment, were compared to those observed when testing on the opposite side a second panel containing 15 µL of aq. solutions of 3 well-known irritants, benzalkonium chloride (BAK) 1%, sodium lauryl sulphate (SLS) 1%, and dimethylsulphoxide (DMSO) 10%. Whilst the substances of the first panel and DMSO gave, on the whole, a scarce number of positive responses in all the tested groups, more evident differences in number, percent and mean intensity of the positive responses to BAK and SLS were found between the different groups. Although some of them seemed statistically significant, when the same values were evaluated by means of χ2 and Student t-test, they did not differ in a statistically significant way from the values found in healthy subjects. The results of this study seem to indicate that the substances of the first panel have a chemical structure that makes them quite safe in real-life conditions. In contrast, BAK and SLS have chemical properties that condition the number and intensity of the responses, making the role exerted by the pre-existing dermatosis quite marginal. In particular, there is no proof that the healthy skin of active atopic subjects is the most susceptible to the irritating effects of the tested substances.