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Notes: Flumazenil (FLU), a benzodiazepine (BZD) partial agonist with a weak intrinsic activity, was previously found unable to precipitate withdrawal in tolerant subjects submitted to long-lasting BZD treatment. The potential use of FLU to treat BZD withdrawal symptoms has also been evaluated tentatively in clinical studies. In the present experiment, FLU (treatment A) was compared with oxazepam tapering (treatment B) and placebo (treatment C) in the control of BZD withdrawal symptoms in three groups of BZD dependent patients. Group A patients (20) received FLU 1 mg twice a day for 8 days, and oxazepam 30 mg in two divided doses (15 mg + 15 mg) during the first night, oxazepam 15 mg during the second night and oxazepam 7.5 mg during the third night. FLU was injected i.v. in saline for 4 hours in the morning and 4 hours in the afternoon, in association with placebo tablets. Group B patients (20) were treated by tapering of oxazepam dosage (from 120 mg) and with saline solution (as placebo) instead of FLU for 8 days. Group C patients (10) received saline instead of FLU and placebo tablets instead of oxazepam for 8 days. FLU immediately reversed BZD effects on balance task and significantly reduced withdrawal symptoms in comparison with oxazepam and placebo on both self-reported and observer-rated withdrawal scales. The partial agonist also reduced craving scores during the detoxification procedure. In addition, during oxazepam tapering, group B patients experienced paradoxical symptoms that were not apparent in FLU patients. Patients treated with FLU showed a significantly lower relapse rates on days 15, 23 and 30 after the detoxification week. Our data provide further evidence of FLUs ability to counteract BZD effects, control BZD withdrawal and normalize BZD receptor function. The effectiveness of FLU may reflect its capacity to upregulate BZD receptors and to reverse the uncoupling between the recognition sites of BZD and GABA, on the GABA A macromolecular complex, that has been reported in tolerant subjects.

Notes: Our aim was to investigate contact sensitization in children over a 7 year period and to compare these data to our previous findings. From January 1995 to December 2001, 1094 children with suspected allergic contact dermatitis were patch tested with our paediatric series of 30 substances. 404 were affected by atopic dermatitis. 570 children (52.1%), 300 girls and 270 boys, proved to be sensitized. Among them, 291 (51%) were polysensitized. Neomycin, nickel sulfate, wool alcohols, thimerosal, ammoniated mercury, and propolis gave the highest number of positive responses. No significant differences were observed in the prevalence of contact sensitization among the patients with atopic dermatitis and non atopics. However, in the latter the frequency of positive responses to nickel sulfate and Kathon CG was significantly lower than in the former. The face (25%), the hands (23%), and the flexural areas of the limbs (18%) were most frequently affected in children with positive patch tests. In this study population the frequency of sensitized children was significantly higher than the one found from 1988 to 1994, in particular for neomycin, nickel sulfate, wool alcohols, ammoniated mercury, propolis, potassium dichromate, mercaptobenzothiazole and thiuram mix. Our data demonstrate that contact sensitization is more and more frequent in children referring to our department and that the importance of some allergens, such as neomycin, wool alcohols, propolis and potassium dichromate, is increasing in the paediatric age with respect to previous results.

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: 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.

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.