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Skin Reactivity (skin + reactivity)
Kinds of Skin Reactivity Selected AbstractsRespiratory allergy in apprentice bakers: do occupational allergies follow the allergic march?ALLERGY, Issue 4 2004J. Walusiak Background:, This prospective study describes the incidence, risk factors and natural history of occupational respiratory allergy in apprentice bakers. Methods:, Two hundred and eighty-seven apprentice bakers were examined using a questionnaire, skin prick tests (SPTs) to common and occupational allergens, evaluation of total serum IgE level and specific anti-flour and , -amylase IgE, before, 1 year and 2 years after the onset of vocational training. To diagnose occupational respiratory disease, spirometry, histamine and allergen-specific inhalation challenge tests were performed. Results:, The incidence of work-related chest symptoms was 4.2% in the first year and 8.6% in the second year of exposure. Hypersensitivity to occupational allergens developed in 4.6 and 8.2% of subjects, respectively. The incidence of occupational allergic rhinitis was 8.4% after 1 year and 12.5% after 2 years, and that of occupational asthma/cough-variant asthma 6.1 and 8.7%, respectively. The latency period of work-related rhinitis symptoms was 11.6 ± 7.1 months and chest symptoms 12.9 ± 5.5 months. Only in 20% of occupational asthmatics could allergic rhinitis be diagnosed a stage earlier. In 21 out of 25 subjects with occupational asthma, chronic cough was the sole clinical manifestation of the disease. Stepwise logistic regression analysis revealed that positive SPT to common allergens was a significant risk factor of hypersensitivity to occupational allergens (OR = 10.6, 95% CI 5.27; 21.45), occupational rhinitis (OR = 3.9, 95% CI 1.71; 9.14) and occupational asthma (OR = 7.4, 95% CI 3.01; 18.04). Moreover, positive SPT to occupational allergens on entry to the training was a significant risk factor of asthma (OR = 6.9, 95% CI 0.93; 51.38). Conclusions:, The incidence of occupational asthma and rhinitis in apprentice bakers is high and increases z with the duration of exposure. Skin reactivity to common and occupational allergens is the main risk factor of bakers' asthma. Most cases of work-related respiratory symptoms among apprentice bakers are related to a specific sensitization. In most subjects who developed occupational asthma, rhinitis occurred at the same time as the chest symptoms did. [source] Skin reactivity to histamine and to allergens in unselected 9-year-old children living in Poland and ItalyPEDIATRIC ALLERGY AND IMMUNOLOGY, Issue 3 2003Roberto Ronchetti Several studies have shown a higher prevalence of positive skin-prick tests to airborne allergens in Western than in Eastern European countries. We have recently reported that skin histamine reactivity significantly increased in Italy over the past 15 years. Population differences in skin histamine reactivity could, at least in part, explain the reported differences in positive allergen skin tests. To test this hypothesis we compared histamine skin reactivity and the prevalence of allergen positive skin-prick tests in a sample of Italian and Polish schoolchildren. A total of 336 unselected 9-year-old-schoolchildren (198 in Italy and 138 in Poland) underwent skin-prick tests with three different histamine concentrations (10, 1 and 0.2 mg/ml) and with a panel of common airborne allergens according to the ISAAC protocol, phase two. Mean wheals elicited by skin-prick tests with the three serial concentrations of histamine were significantly larger (p < 0.001) and shifted more toward higher values (p < 0.001) in Italian than in Polish children. The differences were greater for the intermediate histamine concentration tested (1 mg/ml) than for the highest concentration (10 mg/ml). Skin-prick tests for airborne allergens were more frequently positive in Italian children: wheals ,,3 mm induced by any allergen [odds ratio (OR) 1.69; confidence interval (CI) 0.98,2.92] by Dermatophagoides pteronyssinus (OR 1.92; CI 0.97,3.80) and by D. farinae (OR 3.15; CI 1.16,8.63). Labeling as positive allergen wheal reactions half the size of the 10 mg/ml histamine wheal or larger reduced but did not abolish the Italian,Polish differences. The significantly higher skin histamine reactivity observed in Italian children could help to explain why allergen skin-test reactions differ in the East and West European populations. Moreover, differences in nonallergen-specific factors among populations should be considered in the interpretation of skin test results (e.g. cut-off points). To obtain meaningful results, epidemiological studies of allergies should include serial histamine dilutions. [source] Use of A-type CpG oligodeoxynucleotides as an adjuvant in allergen-specific immunotherapy in humans: a phase I/IIa clinical trialCLINICAL & EXPERIMENTAL ALLERGY, Issue 4 2009G. Senti Summary Background B-type CpG oligodeoxynucleotides (ODN) is currently used in clinical trials because of its prolonged half,life, which is due to its phosphorothioate backbone. A-type CpG ODN is a stronger inducer of IFN but has an unstable phosphodiester backbone that has so far prohibited its clinical use. However, upon association with virus-like particles (VLP) consisting of the bacteriophage Q, coat protein, A-type CpG ODN can be stabilized and can become an efficient adjuvant in mice. Therefore, the phase I/IIa study presented represents the first test of A-type CpGs in humans. Objective To test the safety, tolerability and clinical efficacy of QbG10 as an adjuvant for subcutaneous immunotherapy with a house dust mite (HDM) allergen extract in allergic patients. Methods A single centre, open-label phase I/IIa study evaluated the safety, tolerability and clinical efficacy of QbG10 as an adjuvant to immunotherapy with a subcutaneous HMD allergen extract in 20 patients suffering from HDM allergy. Twenty-one patients were enrolled between March and July 2005. Individual immunotherapy lasted 10 weeks. Clinical end-points included questionnaires, conjunctival provocation, skin prick tests and the measurement of allergen-specific IgG and IgE. Results QbG10 was well tolerated. Almost complete tolerance to the allergen was observed in conjunctival provocation testing after treatment with QbG10, and symptoms of rhinitis and allergic asthma were significantly reduced. Within 10 weeks of therapy, patients were nearly symptom-free and this amelioration lasted for at least 38 weeks post-treatment. Following injections of QbG10 and HDM allergen extract, allergen-specific IgG increased, while there was a transient increase in allergen-specific IgE titres. Skin reactivity to HDM was reduced. Conclusion The subcutaneous application of HDM allergen, together with A-type CpG ODN packaged into VLP, was safe. All patients achieved practically complete alleviation of allergy symptoms after 10 weeks of immunotherapy. This promising clinical outcome calls for larger placebo-controlled phase II studies. [source] Functional map and age-related differences in the human face: nonimmunologic contact urticaria induced by hexyl nicotinateCONTACT DERMATITIS, Issue 1 2006Slaheddine Marrakchi Variation in human skin reactivity to various irritants in association with age and body region has been reported. Hexyl nicotinate (HN), a lipophilic nicotinate ester, was used to induce nonimmunologic contact urticaria in human volunteers of 2 age groups: 10 young subjects [24,34 years, mean ± standard deviation (SD) 29.8 ± 3.9 years] and 10 older volunteers (66,83 years, mean ± SD 73.6 ± 17.4 years); and to define skin function and potential age-related differences in various facial areas. About 5 mM of HN in ethanol was applied to 8 locations on the face, neck, and volar forearm. A laser Doppler flowmeter was used to determine baseline blood flow and to monitor the skin blood flow changes after HN application. In the contralateral areas, stratum corneum turnover was determined using 5% dansyl chloride in petrolatum. In the young group, the perioral area exhibited the strongest reaction to HN. In the older group, the chin was the most sensitive site. In both the groups, the forearm was the least responsive. The older group demonstrated a stronger reaction than the younger group in 3 sites (forehead, cheek, and nasolabial area). Stratum corneum turnover was slower in the nasolabial area and in the forearm in both age groups, whereas the fastest was in the perioral area and the chin in the younger group and in the chin and the forehead in the older group. Compared to the older group, the younger group showed a slower stratum corneum turnover in the nose and the neck. This study demonstrates the regional and the age-related variability of the stratum corneum turnover and the skin reactions to HN. These observations may help explain some aspects of the cutaneous intolerance in skin care of the face. [source] Augmentation of skin response by exposure to a combination of allergens and irritants , a reviewCONTACT DERMATITIS, Issue 5 2004Line Kynemund Pedersen Clinical experimental studies on contact dermatitis (CD) often evaluate the effect of one allergen or one irritant at a time. In real life, the skin is often exposed to more allergens, more irritants or allergens and irritants in combination. This combined exposure may potentially influence irritant effects as well as allergenicity of the substances. Mechanisms for a changed response can be immunological effects or enhanced penetration. Knowledge about the influence on skin reaction of combined exposures may influence skin reactivity and is important for prevention of CD. For allergens, threshold values may be influenced by the presence of other allergens or irritants, and prevention of CD by regulation of threshold values may not be sufficient if this is not taken into account. [source] Use tests: ROAT (repeated open application test)/PUT (provocative use test): an overviewCONTACT DERMATITIS, Issue 1 2000Tokio Nakada As one step in defining the clinical relevance of exposure to an allergen identified with patch testing, use tests (provocative use test (PUT), and repeated open application test (ROAT)) have been used. In 1/2 of the cases of seemingly reliable patch tests, use tests are negative, suggesting that the patient's biologic threshold of response had not been reached with open application dosing. Dramatic differences exist in regional skin reactivity and percutaneous penetration. Negative results of use tests on normal skin may become positive on diseased skin. To refine this assay further, more controlled observations and analysis of reaction differences between normal and damaged skin, and among regional anatomic sites might be performed. In addition, we require a standardized measurement for the results. Use testing has significant potential in refinement of the evidence-based diagnosis of clinical relevance. However, for general validation, we should fill the deficiencies described above. [source] Bimodal skin reactivity to histamine in atopic children in Singapore: influence of specific sensitizationsPEDIATRIC ALLERGY AND IMMUNOLOGY, Issue 6 2004Mona Iancovici Kidon Histamine skin prick test (SPT) is used as the ,golden standard' for positive control in in vivo immediate type hypersensitivity testing. The skin reactivity to histamine can, however, be modulated by a bevy of extraneous factors. We aimed to define whether histamine skin reactivity in atopic children in Singapore is influenced by age, ethnic origin, gender, environmental exposure or specific sensitization patterns. A retrospective analysis of children, with specific aeroallergen sensitization (as measured by at least one allergen-specific SPT with a wheal size >3 mm compared with the negative control) from the outpatient speciality clinic of the KK Children's Hospital, during 06/2002,06/2003. A total of 315 patients were included, 235 (75%) were males, 252 (80%) were Chinese, age mean was 7.7 yr (range: 2,15). Patients were referred to the SPT with a diagnosis of one or more of: allergic rhinitis 287 (91%), asthma 112 (36%) or atopic dermatitis 60 (19%). The mean histamine response showed a bimodal distribution, independent of age, ethnic origin, gender or phenotypical expression of allergic disease. Histamine skin reactivity was higher in atopic patients with polysensitization (mean 5.0 mm vs. 2.9 mm in monosensitized patients, p < 0.001), and in patients with mould sensitization (mean 5.1 mm vs. 3.3 mm in patient not sensitized to moulds, p < 0.001). The presence of passive smoking increased the likelihood of a diminished histamine skin response. Histamine skin response data strongly suggested the presence of two heterogeneous subpopulations. Children with polysensitization and mould sensitization were more likely to show a large significant histamine response, whereas children with passive smoke exposure, showed a diminished skin reactivity to histamine. [source] Skin reactivity to histamine and to allergens in unselected 9-year-old children living in Poland and ItalyPEDIATRIC ALLERGY AND IMMUNOLOGY, Issue 3 2003Roberto Ronchetti Several studies have shown a higher prevalence of positive skin-prick tests to airborne allergens in Western than in Eastern European countries. We have recently reported that skin histamine reactivity significantly increased in Italy over the past 15 years. Population differences in skin histamine reactivity could, at least in part, explain the reported differences in positive allergen skin tests. To test this hypothesis we compared histamine skin reactivity and the prevalence of allergen positive skin-prick tests in a sample of Italian and Polish schoolchildren. A total of 336 unselected 9-year-old-schoolchildren (198 in Italy and 138 in Poland) underwent skin-prick tests with three different histamine concentrations (10, 1 and 0.2 mg/ml) and with a panel of common airborne allergens according to the ISAAC protocol, phase two. Mean wheals elicited by skin-prick tests with the three serial concentrations of histamine were significantly larger (p < 0.001) and shifted more toward higher values (p < 0.001) in Italian than in Polish children. The differences were greater for the intermediate histamine concentration tested (1 mg/ml) than for the highest concentration (10 mg/ml). Skin-prick tests for airborne allergens were more frequently positive in Italian children: wheals ,,3 mm induced by any allergen [odds ratio (OR) 1.69; confidence interval (CI) 0.98,2.92] by Dermatophagoides pteronyssinus (OR 1.92; CI 0.97,3.80) and by D. farinae (OR 3.15; CI 1.16,8.63). Labeling as positive allergen wheal reactions half the size of the 10 mg/ml histamine wheal or larger reduced but did not abolish the Italian,Polish differences. The significantly higher skin histamine reactivity observed in Italian children could help to explain why allergen skin-test reactions differ in the East and West European populations. Moreover, differences in nonallergen-specific factors among populations should be considered in the interpretation of skin test results (e.g. cut-off points). To obtain meaningful results, epidemiological studies of allergies should include serial histamine dilutions. [source] The common G-allele of interleukin-18 single-nucleotide polymorphism is a genetic risk factor for atopic asthma.CLINICAL & EXPERIMENTAL ALLERGY, Issue 2 2006The SAPALDIA Cohort Study Summary Background IL-18 is a pleiotrophic cytokine involved in both, T-helper type 1 (Th1) and Th2 differentiation. Recently genetic variants in the IL-18 gene have been associated with increased risk of atopy and asthma. Objective To examine the relationship of a genetic, haplotype-tagging promotor variant ,137G/C in the IL-18 gene with atopic asthma in a large, well-characterized and population-based study of adults. Methods Prospective cohort study design was used to collect interview and biological measurement data at two examination time-points 11 years apart. Multivariate logistic regression analysis was used to assess the association of genotype with asthma and atopy. Results The G-allele of the IL-18 promotor variant (,137G/C) was associated with a markedly increased risk for the prevalence of physician-diagnosed asthma with concomitant skin reactivity to common allergens. Stratification of the asthma cases by skin reactivity to common allergens revealed an exclusive association of IL-18 ,137 G-allele with an increased prevalence of atopic asthma (adjusted odds ratio (OR): 3.63; 95% confidence interval: (1.64,8.02) for GC or GG carriers vs. CC carriers), and no according association with asthma and concomitant negative skin reactivity (adjusted OR: 1.13; 0.66,1.94). The interaction between IL-18 ,137G/C genotype and positive skin prick test was statistically significant (P=0.029). None of 74 incident asthma cases with atopy at baseline exhibited the CC genotype. Conclusion Our results strongly suggest that this variant of the IL-18 gene is an important genetic determinant involved in the development of atopic asthma. [source] Allergen skin weal/radioallergosorbent test relationship in childhood populations that differ in histamine skin reactivity: a multi-national surveyCLINICAL & EXPERIMENTAL ALLERGY, Issue 4 2005R. Ronchetti No abstract is available for this article. [source] Efficacy and safety of subcutaneous immunotherapy with a biologically standardized extract of Ambrosia artemisiifolia pollen: a double-blind, placebo-controlled studyCLINICAL & EXPERIMENTAL ALLERGY, Issue 9 2004C. Mirone Summary Background The allergological relevance of Ambrosia in Europe is growing but the efficacy of the injective immunotherapy for this allergen has been documented only in Northern America. Objective We sought to study the safety and efficacy of injective immunotherapy in European patients sensitized to Ambrosia artemisiifolia. Methods Thirty-two patients (18 M/14 F, mean age 36.78, range 23,60 years) suffering from rhinoconjunctivitis and/or asthma and sensitized to Ambrosia were enrolled and randomized in a double-blind, placebo-controlled (DBPC) study lasting 1 year. A maintenance dose corresponding to 7.2 ,g of Amb a 1 was administered at 4-week intervals after the build-up. During the second and the third year, all patients were under active therapy in an open fashion. Symptom and medication scores, skin reactivity to Ambrosia (parallel line biological assay), and pollen counts were assessed throughout the trial. Results Twenty-three patients completed the trial. No severe adverse event was observed. During the DBPC phase, actively treated patients showed an improvement in asthmatic symptoms (P=0.02) and drug (P=0.0068) scores days with asthmatic symptoms (P=0.003), days with rhinitis symptoms (P=0.05), and days with intake of drugs (P=0.0058), as compared to before therapy. No improvement for any of these parameters was detected in the placebo group. Moreover, the number of days with rhinitis and asthma was significantly higher in the placebo as compared to the active group (P=0.048 and P<0.0001, respectively). Patients who switched from placebo to active therapy improved in rhinoconjunctivitis, asthma, and drug intake. The skin reactivity decreased significantly (12.2-fold, P=0.0001) in the active group whereas a slight increase (1.07-fold, P=0.87) was observed in the placebo group after the DBPC phase. After switching to active therapy, patients previously under placebo showed a significant decrease of this parameter (4.78-fold, P=0.002). Conclusion Injective immunotherapy is safe and clinically effective in European patients sensitized to Ambrosia. [source] | ||||||||||