Skin reactivity to histamine and to allergens in unselected 9-year-old children living in Poland and Italy

Association of body mass index and season with histamine skin reactivity in Chinese children with allergic rhinitis

BACKGROUND

To investigate the association between histamine skin reactivity and body mass index (BMI) and other clinical factors, 526 children (3-6 years old) who underwent a skin-prick test (SPT) to diagnose allergic rhinitis were enrolled.

METHODS

The SPT was carried out using 43 common allergens (commercial kit). The wheal size was analyzed. The associations between histamine reactivity and age, gender, BMI, atopy, parental smoking history, and testing season were examined.

RESULTS

Mean age was 4.6 ± 1.1 years. Among all 526 children, 202 (38.4%) had intermittent allergic rhinitis (IAR), 164 (32.1%) had IAR + persistent allergic rhinitis (PER), and 160 (30.4%) had PER. The size of the histamine skin wheal and maximum diameter for positive allergens showed significant seasonal differences (P = 0.001 and P = 0.02, respectively). Children with biparental allergy history had a higher BMI (P = 0.006). BMI (P < 0.001), summer testing (P = 0.001), and autumn testing (P < 0.001) were independently associated with the size of the histamine skin wheal. Only winter testing was independently associated with the maximal diameter for positive allergens (P = 0.002).

CONCLUSIONS

Higher histamine skin reactivity was associated with higher BMI and summer or autumn testing. Subject BMI and season should be considered for better interpretation of the SPT. The mechanisms underlying these associations require further study.

Histamine skin reactivity increases with body mass index in Korean children

OBJECTIVE

Histamine skin prick testing is most commonly used to diagnose immunoglobulin E (IgE)-mediated allergic diseases, and histamine reactivity is used as a standardized positive control in the interpretation of a skin prick test. However, reactivity to histamine differs among individuals for reasons that are poorly understood. The present study aimed to evaluate the potential association between body mass index (BMI) and histamine skin reactivity in children.

METHODS

A total of 451 children (246 boys, 205 girls) aged 7-8 years were enrolled in this study. The skin prick test was performed with 26 aeroallergens commonly found in Korea. Other information was collected, including sex, age, BMI, parental allergy history, and parental smoking status. Multivariate analysis was used to confirm the association between histamine skin reactivity and BMI.

RESULTS

The histamine wheal size was revealed to be associated with BMI (Spearman's Rho 0.161, p<0.001). This association was confirmed by multivariate analysis, after adjusting for sex, age, parental allergy history, parental smoking status, and allergic sensitization (coefficient B 0.071, 95% confidence interval 0.030-0.112).

CONCLUSIONS

Skin responses to histamine were primarily correlated with increased BMI. Further studies are needed to understand the clinical implication of BMI when interpreting the results of skin prick test.

Skin prick test reactivity to aeroallergens by filaggrin mutation status

BACKGROUND

Studies have shown that filaggrin gene (FLG) mutations are positively associated with sensitization to aero allergens. We hypothesized that FLG mutations would also have an effect on the mean size of positive skin prick test (SPT) reactions as well as the number of positive reactions.

OBJECTIVE

To investigate the effect of FLG mutations on the mean size and the number of positive SPT reactions, as well as the association with positive specific IgE.

METHODS

A random sample of 3335 adults from the general population in Denmark was genotyped for the R501X and 2282del4 mutations in the FLG. SPT and specific IgE measurements to common aeroallergens were also performed.

RESULTS

FLG mutations did not influence the mean size and number of positive SPT reactions. Also, no association was found between FLG mutations and specific IgE measurements.

CONCLUSION

Our findings suggest that FLG mutations alone are insufficient to cause secondary sensitization to allergens. The positive association seen in patients must be explained by a combination of further barrier abnormality caused by dermatitis as well as increased allergen exposure.

Evaluation of autologous serum skin test and skin prick test reactivity to house dust mite in patients with chronic spontaneous urticaria

Background

Chronic spontaneous urticaria (CSU) is a common skin disorder with etiology that is not well understood.

Methods

In this study, we evaluated the prevalence of autologous serum skin test (ASST) and skin prick testing (SPT) to house dust mite (HDM) in 862 CSU cases in China. Clinical features, courses and treatment responses were also recorded.

Results

The prevalence of positive ASST was 46.3%, and patients aged 30–39 years had the highest positive rate (52.1%). Positive SPT to HDM was seen in 153 patients (17.7%) with the highest positive rate (34.2%) in patients aged 20 or less. Patients with positive ASST had higher urticaria activity scores (UAS) (4.18±0.65 vs. 3.67±0.53) but lower positive rates of HDM (24.6% vs. 37.6%), as compared with those with negative ASST (odds ratio (OR) 1.84, 95% CI 1.38–2.47). Patients could be categorized into four groups based on the results of ASST and SPT to HDM and patients with positive ASST and positive SPT to HDM had the highest disease activity scores, experienced higher frequencies of angioedema, diseases duration, and required higher dosage of loratadine every month, compared with other subgroups (P<0.0001).

Conclusions

Patients with CSU showed varied responses of positive ASST and varied sensitivity to HDM, Patients with positive ASST and/or positive SPT had more disease activity compared with patients with negative ASST and/or negative SPT. Further classification can be made based on the result of SPT and ASST.

GA(2)LEN skin test study I: GA(2)LEN harmonization of skin prick testing: novel sensitization patterns for inhalant allergens in Europe

BACKGROUND

Skin prick testing is the standard for diagnosing IgE-mediated allergies. However, different allergen extracts and different testing procedures have been applied by European allergy centres. Thus, it has been difficult to compare results from different centres or studies across Europe. It was, therefore, crucial to standardize and harmonize procedures in allergy diagnosis and treatment within Europe.

AIMS

The Global Asthma and Allergy European Network (GA(2)LEN), with partners and collaborating centres across Europe, was in a unique position to take on this task. The current study is the first approach to implement a standardized procedure for skin prick testing in allergies against inhalant allergens with a standardized pan-European allergen panel.

METHODS

The study population consisted of patients who were referred to one of the 17 participating centres in 14 European countries (n = 3034, median age = 33 years). Skin prick testing and evaluation was performed with the same 18 allergens in a standardized procedure across all centres.

RESULTS

The study clearly shows that many allergens previously regarded as untypical for some regions in Europe have been underestimated. This could partly be related to changes in mobility of patients, vegetation or climate in Europe.

CONCLUSION

The results of this large pan-European study demonstrate for the first time sensitization patterns for different inhalant allergens in patients across Europe. The standardized skin prick test with the standardized allergen battery should be recommended for clinical use and research. Further EU-wide monitoring of sensitization patterns is urgently needed.

Messages from the Aalst Allergy Study

BACKGROUND

The prevalence of sensitization and allergic disease has increased significantly worldwide. The aim of the "Aalst Allergy Study" was to document prevalences of sensitization and allergic symptoms, and to evaluate the effect of personal and environmental influences on these prevalences in an unbiased Belgian pediatric population.

METHODS

A cross-sectional study was performed in an unbiased population of 2021 Belgian schoolchildren (3.4-14.8 years). Skin prick testing with the most common aeroallergens was performed. Allergic symptoms as well as potential risk factors for sensitization and allergic disease were documented by a parental questionnaire.

RESULTS

The prevalence of sensitization to the most common aeroallergens and the prevalence of allergic diseases (eczema, asthma and rhinoconjunctivitis) were in line with the data in the literature. The association of current allergic symptoms with sensitization was only significant in the children aged > or =6 years. Age, gender, body mass index, bedroom environment and exposure to pets were the factors significantly associated with sensitization and allergic symptoms.

CONCLUSIONS

Our study corroborates the reported prevalences of sensitization and allergic diseases. Moreover the study illustrates the complexity of the search for factors involved in the process of sensitization and allergic disease. The impact of different potential causative factors is not only influenced by mutual interactions of these factors, but also by the existence of distinct subtypes of disease.

The prevalence of atopy in asthmatic children correlates strictly with the prevalence of atopy among nonasthmatic children

BACKGROUND

Because asthma preferentially burdens persons with atopy, atopy is simplistically considered a primary 'cause' of asthma. Yet at the population level, the percentage of asthma cases 'attributable' to atopy ranges from less than 10% to more than 60%. Seeking to understand the rationale for the variability of atopy-attributable cases of asthma, we systematically reviewed the results of our own previous epidemiological studies and several studies conducted by others in children.

METHODS

From each of the 37 random pediatric populations selected by a Medline search combining the key words 'IgE or skin tests or hypersensitivity, immediate' with 'epidemiological studies, cross-sectional, case-control, prevalence, longitudinal, epidemiology of asthma' (12 from our previous pediatric surveys and a further 25 reported from 19 studies in children), we extracted the population prevalence of asthma and atopy among asthmatic subjects and among the nonasthmatic part of the population.

RESULTS

No correlation was found between the prevalence of asthma (range 1.8-44.1%) and atopy (range 5.8-63.9%) in these 37 populations of children (r = 0.052, p = 0.761). Nevertheless, the prevalence of atopy among asthmatics strictly correlated with the prevalence of atopy in nonasthmatics (r = 0.900, p < 0.001, slope 1.364).

CONCLUSION

The prevalence of asthma and atopy varies worldwide and at various time points and independently undergoes the influence of powerful environmental factors. The almost perfect correlation we found between atopy in asthmatics and atopy in the nonasthmatic part of the childhood population shows that the prevalence of atopy in asthma depends on environmental factors that simultaneously induce atopy in asthmatic and nonasthmatic subjects.

Standard skin prick testing and sensitization to inhalant allergens across Europe--a survey from the GALEN network

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 (GA(2)LEN). 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 GA(2)LEN Pan-European core SPT panel.

Allergen skin weal/radioallergosorbent test relationship in childhood populations that differ in histamine skin reactivity: a multi-national survey

BACKGROUND

Histamine skin reactivity (HSR, the dimension of the skin weal elicited by histamine 10 mg/mL) is a variable that differs in children from different European countries and increases over time in the same place (Italy).

OBJECTIVE

In this epidemiologic study, we investigated to what extent differences in HSR influence the relationship between positive allergen skin prick tests (ASPTs) and serum-specific IgE concentrations.

METHODS

Between October 2001 and February 2002, 591 unselected 9-10-year-old schoolchildren drawn from five small towns in central Poland (Starachowice), central Italy (Ronciglione, Guardea) and Libya (Al-Azyzia, near the Mediterranean sea and Samno, 900 km south of the coast) were analysed for histamine, common ASPT and for serum total and specific IgE.

RESULTS

HSR differed markedly in children from the three countries (Libya>Italy>Poland) whereas serum total IgE concentrations remained the same. The prevalence of children with measurable serum specific IgE (> or = 0.35 kU) or with a positive ASPT for five common allergens was high in Italy, lower in Poland and far lower in Libya. A 3-mm ASPT weal corresponded to a serum-specific IgE concentration that was two to threefold higher in children with low HSR compared with children with high HSR (P = 0.008).

CONCLUSION

These findings suggest that HSR--a variable that differs in schoolchildren populations from the three countries studied--independently influences the results of ASPT and its influence should be considered when ASPT are assessed in international studies. The HSR differences found in the populations reported here probably reflect a complex, dynamic, environmental interaction that should be monitored in the different parts of the world.

Bimodal skin reactivity to histamine in atopic children in Singapore: influence of specific sensitizations

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.

Skin Reactivity to Histamine and Codeine in Unselected 9-Year-Old Children from Italy, Poland and Libya

BACKGROUND

Previous studies have shown that histamine skin reactivity (the dimensions of a skin wheal elicited by a prick with histamine 10 mg/ml) in unselected school children has increased in Italy during the past two decades and is higher in Italy than in Poland. Hence this variable can probably be influenced by a changing or different lifestyle. The aim of this study was to compare skin reactivity to histamine and codeine (a marker of histamine releasability from mast cells) in schoolchildren from countries with different lifestyles.

METHODS

Six previously unstudied unselected populations of 9-year-old schoolchildren (two each from Poland, Italy, and Libya; n = 863 subjects; 49.0% males) were pricked with two concentrations of histamine (10 and 1 mg/ml) and codeine (90 and 9 mg/ml).

RESULTS

The higher concentrations of both pharmacologic agents tested yielded significantly different wheal areas in the three countries: Poland < Italy < Libya (histamine, 11.8, 16.1 and 20.7 mm2; codeine, 9.2, 13.2 and 16.2 mm2; p < 0.001 for all comparisons). The lower concentrations elicited almost matching results. Histamine wheal areas correlated closely with areas elicited by codeine in the same individual: angular coefficients of the histamine to codeine regression lines were 0.535, Italy; 0.551, Libya; 0.612, Poland; and 0.581 for the whole population. More histamine was needed to produce a wheal in Poland than in Libya: a 20-mm2 wheal required an injected histamine concentration of about 8.8 mg/ml in Libya, 29.5 mg/ml in Italy and 102.1 mg/ml in Poland.

CONCLUSION

More studies are necessary to explain the observed international differences in skin histamine reactivity and their effect on the prevalence of positive allergen skin tests.