Prick Test Reactivity Research Articles

Skin prick test reactivity in atopic children and their number of siblings

Background Some studies have shown that low birth order is a risk factor for developing atopy, although these results remain inconclusive. Those studies put forth the hygiene hypothesis, which states that early childhood infections in siblings may protect against atopy. Hence, an inverse relationship between family numbers and atopy was found. Atopy may be diagnosed from a history of atopy in an individual or his family, and can be confirmed by specific IgE for allergens or positive skin prick tests.Objective To assess for an association between skin prick test reactivity in atopic children and their number of siblings.Methods A cross-sectional study was conducted in May to June 2010 in elementary school children at the Kampung Baru District, Medan Regency, North Sumatera. Subjects were divided into two groups. Group I had children with < 3 siblings and group II had children with ≥ 3 siblings. Skin prick tests were done in 7 to 10-year-old children with a history of asthma, allergic rhinitis and atopic dermatitis. Skin prick test reactivity results were analyzed by Chi-square test.Results A total of 192 subjects were enrolled in this study, with 96 subjects in each group. Positive skin prick tests were significantly higher in subjects with <3 siblings than in those with >3 siblings (75% and 53.1%, respectively; P=0.003).Conclusion Atopic children with <3 siblings had more positive skin prick tests than children with >3 siblings.

Skin prick test reactivity in atopic children and their number of siblings

Background Some studies have shown that low birth order is a risk factor for developing atopy, although these results remain inconclusive. Those studies put forth the hygiene hypothesis, which states that early childhood infections in siblings may protect against atopy. Hence, an inverse relationship between family numbers and atopy was found. Atopy may be diagnosed from a history of atopy in an individual or his family, and can be confirmed by specific IgE for allergens or positive skin prick tests.Objective To assess for an association between skin prick test reactivity in atopic children and their number of siblings.Methods A cross-sectional study was conducted in May to June 2010 in elementary school children at the Kampung Baru District, Medan Regency, North Sumatera. Subjects were divided into two groups. Group I had children with < 3 siblings and group II had children with ≥ 3 siblings. Skin prick tests were done in 7 to 10-year-old children with a history of asthma, allergic rhinitis and atopic dermatitis. Skin prick test reactivity results were analyzed by Chi-square test.Results A total of 192 subjects were enrolled in this study, with 96 subjects in each group. Positive skin prick tests were significantly higher in subjects with <3 siblings than in those with >3 siblings (75% and 53.1%, respectively; P=0.003).Conclusion Atopic children with <3 siblings had more positive skin prick tests than children with >3 siblings.

Allergic disorders and socio‐economic status: a study of schoolchildren in an urban area of Makassar, Indonesia

In urban centres of developing countries, there is great variation in socio-economic status (SES) and lifestyle; however, little information is available on allergic disorders in groups with high- or low-SES within the same urban area. To determine the prevalence of allergic disorders and investigate risk factors related to them among high- and low-SES schoolchildren in Makassar, the capital city of South Sulawesi, Indonesia. This cross-sectional study was performed in 623 children originating from high- (N = 349) and low-SES (N = 274) schools. Information on reported allergic symptoms and potential factors associated with allergic disorders was obtained by questionnaire. Specific IgE and skin prick test (SPT) reactivity were determined against aeroallergens [Dermatophagoides pteronyssinus (HDM) and cockroach]. Total IgE and helminth infections were also assessed. The prevalence of SPT to any aeroallergens was significantly higher in high-SES than in low-SES school (25% vs. 8%, P < 0.001, respectively). However, specific IgE against cockroach and total IgE were significantly lower in high- than in low-SES children. Allergic symptoms were reported more often in low- compared to high-SES children. Specific IgE to aeroallergens significantly increased the risk of SPT positivity to the same aeroallergen in the high-, but not in the low-SES children. In the high- but not in low-SES, there was a significant positive association between SPT to HDM and wheeze. Similarly, cockroach skin reactivity and elevated BMI increased the risk of eczema in the high-SES children only. Skin prick test is higher in high-SES, whereas IgE and allergic symptoms are higher in low-SES children. Specific IgE is a risk factor for being SPT-positive, and SPT positivity is a risk factor for allergic symptoms but only in children of high- and not low-SES school. Therefore, the socio-economic status of a child might affect the diagnosis of allergic disease in a developing country.

Serum vitamin D levels in a cohort of adult and pediatric patients with eosinophilic esophagitis

BackgroundVitamin D deficiency has been associated with increased risk for severe asthma, challenge-proven food allergy, and severe atopic dermatitis. Vitamin D levels have not been reported in patients with eosinophilic esophagitis (EoE). ObjectiveTo determine levels of 25-hydroxyvitamin D in a cohort of patients with EoE. MethodsTotal serum 25-hydroxyvitamin D was measured using liquid chromatography with tandem mass spectroscopy in adults (n = 35) and children (n = 34) with EoE. Results were compared with patient demographics, EoE-specific disease parameters, markers of sensitization, and features of severity using multivariable logistic regression. ResultsThe median vitamin D level was 28.9 ng/mL. Patients with insufficient vitamin D (<30 ng/mL) were older (median 25.5 vs 16.2 years) and had a higher body mass index (median 25.2 vs 19.8 kg/m2). Peak median esophageal eosinophil counts were not significantly different for vitamin D insufficient and sufficient patient groups; however, higher vitamin D levels correlated with higher histologic eosinophil counts (R = 0.61, P = .03). Although there were no statistical differences in total IgE or levels of specific IgE between patients with vitamin D insufficiency and those with sufficiency, a positive skin prick test reaction to peanut was more common in patients who had vitamin D insufficiency (adjusted odds ratio 7.57, P = .009). Vitamin D insufficiency was not associated with surrogate markers of severity (dilation in adults or hospitalization or emergency visits in children). ConclusionIn these patients with EoE, vitamin D levels were low overall (median <30 ng/mL). The only marker of sensitization associated with insufficient vitamin D in these patients with EoE was a positive skin prick test reaction to peanut.

Incidence and natural history of challenge-proven cow's milk allergy in European children--EuroPrevall birth cohort.

Cow's milk allergy (CMA) is one of the most commonly reported childhood food problems. Community-based incidence and prevalence estimates vary widely, due to possible misinterpretations of presumed reactions to milk and differences in study design, particularly diagnostic criteria. Children from the EuroPrevall birth cohort in 9 European countries with symptoms possibly related to CMA were invited for clinical evaluation including cows' milk-specific IgE antibodies (IgE), skin prick test (SPT) reactivity and double-blind, placebo-controlled food challenge. Across Europe, 12049 children were enrolled, and 9336 (77.5%) were followed up to 2years of age. CMA was suspected in 358 children and confirmed in 55 resulting in an overall incidence of challenge-proven CMA of 0.54% (95% CI 0.41-0.70). National incidences ranged from 1% (in the Netherlands and UK) to <0.3% (in Lithuania, Germany and Greece). Of all children with CMA, 23.6% had no cow's milk-specific IgE in serum, especially those from UK, the Netherlands, Poland and Italy. Of children with CMA who were re-evaluated one year after diagnosis, 69% (22/32) tolerated cow's milk, including all children with non-IgE-associated CMA and 57% of those children with IgE-associated CMA. This unique pan-European birth cohort study using the gold standard diagnostic procedure for food allergies confirmed challenge-proven CMA in <1% of children up to age 2. Affected infants without detectable specific antibodies tocow's milk were very likely to tolerate cow's milk one year after diagnosis, whereas only half of those with specific antibodies in serum 'outgrew' their disease so soon.

Neonatal vitamin A supplementation associated with increased atopy in girls.

Neonatal vitamin A supplementation (NVAS) is currently being considered as policy in countries at risk of deficiency. A previous study suggested that NVAS may be associated with increased atopy. We examined the effect of NVAS on atopy by conducting long-term follow-up of a previous randomized controlled trial in Guinea-Bissau. In 2002-2004, we randomized 4345 normal birthweight neonates to NVAS (50000IU retinyl palmitate) or placebo together with their Bacillus Calmette-Guérin vaccination. In 2013, we visited the 1692 (39%) children now aged 8-10years who were still living in the study area, and 1478 (87%) were found at home. Provided consent, a skin prick test was performed, and history of allergic symptoms was recorded. Associations of NVAS and atopy (defined as skin prick test reaction of ≥3mm) were analysed using binomial regression. Of the 1430 children with a valid skin prick test, 228 (16%) were positive (more boys (20%) than girls (12%), P-value<0.0001). NVAS did not increase the overall risk of atopy (RR 1.10 [95% CI 0.87-1.40]). However, NVAS was associated with significantly increased risk among females (RR 1.78 [1.17-2.72]) but not among males (0.86 [0.64-1.15], P-value for interaction between NVAS and gender=0.005). Furthermore, NVAS was associated with increased risk of wheezing among females (RR 1.80 [1.03-3.17], but not among males, P-value for interaction=0.05). The study corroborated previous observations; NVAS was associated with increased risk of atopy and wheezing, in this study only among females. Further studies on NVAS and atopy are warranted.

Decrease in the rate of sensitization and clinical allergy to natural rubber latex.

In the 1980s, a striking increase in natural rubber latex (NRL) allergy was seen. Since then, many measures have been taken to prevent NRL allergy. To investigate changes in the prevalence of NRL sensitization/clinical NRL allergy over time from 2002 to 2013. All patients prick tested for NRL at the Department of Dermatology and Allergy Centre, Odense University Hospital were included in this study (n = 8580). In NRL-sensitized patients, the clinical relevance was evaluated for NRL. Furthermore, concomitant positive prick test results for birch pollen were recorded, together with food-related symptoms and sensitization in a subgroup of patients. The prevalence of NRL sensitization declined from 6.1% in 2002-2005 to 1.9% in 2006-2009, and then to 1.2% in 2010-2013 (p < 0.0001). The prevalence of clinical NRL allergy declined from 1.3% in 2002-2005 to 0.5-0.6% in 2006-2013 (p < 0.004). Among the NRL-sensitized patients, 64% had a concomitant positive prick test reaction to birch pollen, and 52% had a history of reaction to oral intake of related fruits or vegetables. Our study showed a statistically significant decline in the number of patients sensitized/clinically allergic to NRL. Many of the NRL-sensitized patients without clinical allergy to NRL had concomitant birch pollen sensitization, and reported food-related symptoms.

Effect of urban vs. rural residence on the association between atopy and wheeze in Latin America: findings from a case-control analysis.

BackgroundThe association between atopy and asthma is attenuated in non-affluent populations, an effect that may be explained by childhood infections such as geohelminths.ObjectiveTo investigate the association between atopy and wheeze in schoolchildren living in urban and rural areas of Ecuador and examine the effects of geohelminths on this association.MethodsWe performed nested case–control studies among comparable populations of schoolchildren living in rural communities and urban neighbourhoods in the Province of Esmeraldas, Ecuador. We detected geohelminths in stool samples, measured recent wheeze and environmental exposures by parental questionnaire, and atopy by specific IgE (sIgE) and skin prick test (SPT) reactivity to aeroallergens.ResultsAtopy, particularly sIgE to house dust mite (HDM), was more strongly associated with recent wheeze in urban than rural schoolchildren: (urban, adj. OR 5.19, 95% CI 3.37–8.00, P < 0.0001; rural, adj. OR 1.81, 95%CI 1.09–2.99, P = 0.02; interaction, P < 0.001). The population fractions of wheeze attributable to atopy were approximately two-fold greater in urban schoolchildren: SPT to any allergen (urban 23.5% vs. rural 10.1%), SPT to HDM (urban 18.5% vs. rural 9.6%), and anti-HDM IgE (urban 26.5% vs. rural 10.5%), while anti-Ascaris IgE was related to wheeze in a high proportion of rural (49.7%) and urban (35.4%) children. The association between atopy and recent wheeze was attenuated by markers of geohelminth infections.ConclusionsOur data suggest that urban residence modifies the association between HDM atopy and recent wheeze, and this effect is explained partly by geohelminth infections.

Cellular cytokine and chemokine responses to parasite antigens and fungus and mite allergens in children co-infected with helminthes and protozoa parasites.

BackgroundIn sub-Saharan Africa poly-parasite infections are frequently observed in children, and with poly-parasitism modulating immune mechanisms, mediated by cytokines and chemokines, are required to prevent overwhelming inflammation and host tissue damage. We analyzed in children co-infected with helminthes and protozoan parasites their cellular production of regulatory and pro-inflammatory cytokines and chemokines in response to parasite antigens and allergens.MethodsIntestinal and intravascular parasite infections were detected in stool and urines samples. The in vitro cellular cytokine and chemokine responses of peripheral blood mononuclear cells (PBMC) to parasite antigens and allergens were analysed in children (n = 87) with single and poly-parasite infection, and skin prick test reactivity to fungus and mite allergens was determined in singly and poly-parasitized children (n = 509).ResultsIn children Entamoeba histolytica/dispar (62%), Necator americanus (31%), Schistosoma haematobium (28%), S. mansoni (21%), Hymenolepis nana (2%) and Strongyloides stercoralis (1%) were diagnosed. Singly infected were 37%, 47% were positive for 2 or more parasite species and 16% were infection-free. When PBMC were stimulated in vitro with parasite antigens and allergens, regulatory-type cytokine IL-27 and alarmin-type IL-33 enhanced with poly-parasite infections whilst IL-10 and pro-inflammatory MIP3-α/CCL20 and MIG/CXCL9 were produced in similar amounts in singly or poly-parasitized children. The co-stimulation in vitro of PBMC with mite allergens and Ascaris lumbricoides antigens depressed the allergen-induced pro-inflammatory IL-27, IL-33 and MIP3-α/CCL20 responses while regulatory IL-10 remained unaffected. Post albendazole and/or praziquantel treatment, the cellular release of IL-10, IL-33, MIP3-α/CCL20 and MIG/CXCL9 lessened significantly in all children infection groups. Skin prick test (SPT) reactivity to fungus Aspergillus fumigatus and mite Dermatophagoides pteronyssinus allergens was investigated in 509 children, and positive SPT responses were found in 23% of the infection-free, and in 47%, 53% and 56% of the singly, doubly and poly-parasite infected, respectively.ConclusionsIn children co-infected with helminthes and protozoan parasites a mixed cellular response profile of both inflammatory and regulatory chemokines and cytokines was stimulated by individual antigens and allergens, pro-inflammatory cytokines and chemokines enhanced with an increasing number of parasite infections, and in poly-parasitized children skin prick test reactivity to allergens extracts was highest.

Influence of glucocorticoid receptor gene NR3C1 646 C>G polymorphism on glucocorticoid resistance in asthmatics: a preliminary study.

BackgroundGlucocorticoid receptor gene polymorphism (NR3C1 646 C>G) may play an important role in the development of severe bronchial asthma and resistance to glucocorticoids (GCs).ObjectiveThe aim of the present study was to determine the relation between the 646 C>G polymorphism of the glucocorticoid receptor gene (NR3C1) and resistance to GCs with development of severe bronchial asthma.Material and methodsThis case-control study included 40 patients with severe bronchial asthma and 20 apparently healthy controls. Atopic status was determined by skin prick test reaction to the most common locally-encountered allergens. GCs reversibility test was performed to differentiate between GCs sensitive and GCs resistant asthma. For all subjects, analysis of the glucocorticoid receptor gene polymorphism (NR3C1 646 C>G) was done using polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP).ResultsThe frequencies of NR3C1 646 C>G genotypes and alleles differed significantly between asthmatic patients and controls. The frequencies of the CC genotype and C allele carriers were significantly higher among asthmatics than among controls, and also among GCs sensitive asthmatics than among GCs resistant asthmatics. However, NR3C1 646 C>G genotypes and alleles frequencies did not differ significantly according to the atopic status in asthmatics.ConclusionsThe too small sized of the investigated groups is a shortcoming of this study. Nevertheless, the observed variations demonstrate a marked association of NR3C1 646 C>G CC genotype with the development of bronchial asthma and a higher frequency of the C allele among GCs sensitive asthmatics. Large-scale studies are required to investigate the association between polymorphisms of the NR3C1 gene and GCs resistance among asthmatic patients.

Biological and genetic markers in occupational asthma.

Occupational asthma (OA) is a complex disease that is often hard to diagnose due to difficulties in detecting relevant exposure, along with inherent differences in disease susceptibility. Numerous studies have attempted to identify relevant biological and genetic markers for OA and to devise tools capable of detecting exposure to the causative agent. Immunological markers, including skin prick test reactivity and specific IgE and IgG antibodies can be used to detect high-molecular-weight allergens in cases of baker's asthma. For OA induced by low-molecular-weight agents, such as isocyanate, potential biomarkers include serum-specific IgE and IgG antibodies to isocyanate-HSA conjugate and IgG to cytokeratin 19 and transglutaminase-2. For protein-based markers, ferritin/transferrin and vitamin D-binding protein levels have been suggested for isocyanate-OA. Genetic markers of susceptibility to isocyanate-OA include human leukocyte antigen and CTNNA3. Further investigations will be needed to identify better biomarkers for OA, which may be used to inform clinical decision.

Different sensitization to storage mites depending on the co-exposure to house dust mites

BackgroundCo-sensitization to house dust mites (HDMs) and storage mites (SMs) is very frequent, although the clinical relevance is not well established. ObjectiveTo describe the pattern of sensitization and immunologic characterization of patients with positive skin prick test reactions to HDMs and SMs in 4 areas of Spain, selected according to high exposure to HDMs and variable exposure to SMs. MethodsOne hundred sixty-nine individuals with positive skin prick test reactions to HDMs and SMs were included. Specific IgE levels to different mite species and to Der p 1, Der p 2, and Der p 10 were determined. Immunoblots to Dermatophagoides pteronyssinus, Lepidoglyphus destructor, and Tyrophagus putrescentiae extracts were carried out, and allergograms were obtained. Results of different areas were compared. ResultsA high rate of polysensitization to SMs was observed, although 12% of participants did not have specific IgE to any SM species. Sensitization to Dermatophagoides species, Der p 2, and L destructor were predominant, although significant differences were observed among areas depending on the grade of exposure to SMs. In areas with high exposure, the SM allergogram showed greater recognition of group 2 allergen. ConclusionSensitization patterns to SMs in patients sensitized to HDMs and SMs differ depending on the exposure to SMs. Sensitization, mainly to L destructor, seems to exist in areas with high exposure, possibly with group 2 allergens mainly involved. However, in areas with low SM populations, sensitizations observed by skin prick testing appear to be related to HDM exposure.

Asthma and insulin resistance in obese children and adolescents.

Obese children and adolescents have an increased risk for asthma. A few studies have evaluated the association of insulin resistance and asthma in obese pediatric populations. We examined whether there was a relationship between high degrees of insulin resistance and the presence of asthma in obese children and adolescents. A total of 153 patients aged 4-15 years with at or above the 95th percentile BMI for age were prospectively recruited. Assessments included diagnosis of asthma, skin prick test reactivity to common environmental aeroallergens, and HOMA estimated insulin resistance, with the median (2.22) used as a cutoff value to categorize insulin resistance. There were 56 (36.6%) asthmatic and 97 (63.4%) non-asthmatic patients. HOMA values were significantly associated with positive skin tests (p = 0.008) and allergic asthma diagnosis (p = 0.016). Baseline insulin value was significantly associated with the risk of presenting asthma with positive skin testing (odds ratio 1.084, p = 0.037). Differences in age, BMI, and waist circumference were found between the groups of HOMA-IR <2.22 and ≥2.22. Waist circumference (WC) was significantly associated with FVC (p = 0.0001) and FEV1 (p < 0.0003); the greater the WC, the lower FVC and FEV1 values. Insulin resistance is a risk for allergic asthma in obese children and adolescents. Waist circumference was related to CVF and FEV1 impairment.

Prick testing with chemicals in the diagnosis of occupational contact urticaria and respiratory diseases.

Little is known about the use of prick tests with chemicals in diagnosing occupational diseases. To evaluate the use of prick tests in the diagnosis of occupational contact urticaria, asthma and rhinitis caused by chemicals (undertaken at the Finnish Institute of Occupational Health). We retrospectively reviewed the patient and test files for the period 1 January 1991 to 31 May 2011. Prick tests were performed with chemical solutions and human serum albumin (HSA)-chemical conjugates. Positive prick test reactions to isocyanate-HSA conjugates were associated with isocyanate-specific IgE in all 20 patients, and 17 patients had a relevant occupational disease. Positive reactions to chloramine-T-HSA conjugates in 10 patients also indicated the presence of specific IgE, although occupational diseases were not always diagnosed. Eleven of 17 patients with positive reactions to persulfate solutions were diagnosed with an occupational disease. Methacrylates, colophonium-related substances, amine hardeners, ethanolamines, glutaraldehyde, glyoxal, pyrocatechol and ammonium thioglycolate did not elicit any relevant prick test reactions. No generalized reactions were detected. Prick tests can be safely used for diagnosing contact urticaria, asthma and rhinitis caused by isocyanates, chloramine-T, persulfates, and chlorhexidine, but the results should be carefully interpreted and related to clinical symptoms and other diagnostic tests.

Prevalence of various types of allergens in ocular allergic conditions of patients from Pokhara, Nepal

Introduction: Ocular allergic conditions are mostly recurrent and the drugs prescribed, especially corticosteroids, have serious side effects. Therefore, when maximal tolerated topical and systemic medications are unable to control allergic conjunctivitis, a skin prick test for allergens should be conducted and patients should be taught to avoid these allergens. Objective: To find out the prevalence of common allergens inciting ocular allergic diseases in Nepal. Subjects and methods: A total of 13,376 skin prick tests were performed on 76 patients suffering from different chronic recurrent ocular allergic conjunctivitis with 176 common allergens (pollens, fungi, insects, dusts, danders, fabrics/ feathers, food, parthenium leaves, tobacco and mite). Buffer saline was used as a negative control while histamine acid phosphate was used as a positive control. Grading of the skin prick test reaction was done by comparison to the histamine positive control. Only markedly positive reactions were considered positive. Relevant data were entered into the excel spreadsheet and analyzed with the Stata-12 commercial package. The association between allergic conditions and socio-demographic, environmental and other co-variates were tested by the chi-square test. Results: The common offenders found in the study were mite (42.11 %) followed by fabrics/ feathers (20.39 %), dusts (18.18 %), pollen (17.05 %), non-juicy food (15.02 %), dander (13.60 %), juicy food (11.64 %) and fungus (9.87 %), and tobacco (6.58 %), parthenium leaves (5.26 %) and insects (3.17 %) were less common offenders. Conclusions: All ocular allergy patients should undergo skin prick tests to find out the allergens causing their allergy and then receive specific immunological treatment (SIT). DOI: http://dx.doi.org/10.3126/nepjoph.v6i1.10759 Nepal J Ophthalmol 2014; 6 (2): 6-23

Cohort Profile: The Ecuador Life (ECUAVIDA) study in Esmeraldas Province, Ecuador.

The ECUAVIDA birth cohort is studying the impact of exposures to soil-transmitted helminth (STH) parasites and early-life microbial exposures on the development of atopy, allergic diseases and immune responses in childhood. A total of 2404 newborns were recruited between 2006 and 2009 in a public hospital serving the rural district of Quininde, Esmeraldas Province, in a tropical region of coastal Ecuador. Detailed measurements were done around the time of the birth, at 7 and 13 months and at 2 and 3 years, and data collection is ongoing at 5 and 8 years. Data being collected include questionnaires for: sociodemographic, lifestyle, psychosocial (at 4–6 years only) and dietary (at 6–7 years only) factors; childhood morbidity and clinical outcomes; stool samples for parasites; blood samples for DNA, measurements of vaccine responses and other measures of immune function/inflammation; and anthropometrics. Allergen skin prick test reactivity is done from 2 years and measures of airway function and inflammation at 8 years.

Schistosome infection is negatively associated with mite atopy, but not wheeze and asthma in Ghanaian Schoolchildren

Epidemiological evidence suggests that helminth infection and rural living are inversely associated with allergic disorders. The aim of the study was to investigate the effect of helminth infections and urban versus rural residence on allergy in schoolchildren from Ghana. In a cross-sectional study of 1385 children from urban-high socio-economic status (SES), urban-low SES and rural schools, associations between body mass index (BMI), allergen-specific IgE (sIgE), parasitic infections and allergy outcomes were analysed. Allergy outcomes were skin prick test (SPT) reactivity, reported current wheeze and asthma. Helminth infections were found predominantly among rural subjects, and the most common were hookworm (9.9%) and Schistosoma spp (9.5%). Being overweight was highest among urban-high SES (14.6%) compared to urban-low SES (5.5%) and rural children (8.6%). The prevalence of SPT reactivity to any allergen was 18.3%, and this was highest among rural children (21.4%) followed by urban-high SES (20.2%) and urban-low SES (10.5%) children. Overall, SPT reactivity to mite (12%) was most common. Wheeze and asthma were reported by 7.9% and 8.3%, respectively. In multivariate analyses, factors associated with mite SPT were BMI (aOR 2.43, 95% CI 1.28-4.60, P = 0.007), schistosome infection (aOR 0.15, 95% CI 0.05-0.41) and mite sIgE (aOR 7.40, 95% CI 5.62-9.73, P < 0.001) but not area. However, the association between mite IgE and SPT differed by area and was strongest among urban-high SES children (aOR = 15.58, 95% CI 7.05-34.43, P < 0.001). Compared to rural, urban-low SES area was negatively associated with current wheeze (aOR 0.41, 95% CI 0.20-0.83, P = 0.013). Both mite sIgE and mite SPT were significantly associated with current wheeze and asthma. Infection with schistosomes appeared to protect against mite SPT reactivity. This needs to be confirmed in future studies, preferably in a longitudinal design where schistosome infections are treated and allergic reactions reassessed.

Skin prick test reactivity to lupin in comparison to peanut, pea, and soybean in atopic and non-atopic German subjects: A preliminary cross-sectional study.

The increasing use of lupin in food processing poses a problem of potential (cross-)allergic reactions. To evaluate the prevalence of sensitization to lupin in comparison to that of other legumes skin prick tests were performed with lupin, pea, peanut, and soybean in atopic (n = 81) and non-atopic (n = 102) German adults. Of these 183 subjects, 20 subjects had to be excluded due to invalid skin prick tests (reaction to histamine <3 mm or to sodium chloride >2 mm). Thus, skin prick tests of 163 subjects were included in final analyses. Of 163 subjects, 18 had a positive reaction to at least one legume tested. Overall skin prick test reactivity was different among non-atopic and atopic subjects (P = 0.005). Altogether, six subjects (4%) were sensitized to lupin, 12 (7%) to pea, 5 (3%) to peanut, and 8 (5%) to soybean. Two (2%) of the 92 non-atopic subjects and 4 (6%) of the 71 atopic subjects had a positive skin prick test to lupin. Of the 6 subjects sensitized to lupin, 3 (50%) were also sensitized to pea, 3 (50%) to peanut, and 5 (83%) to soybean. In conclusion, the prevalence rates of lupin sensitization were comparable to or even lower than those of pea, peanut, and soybean. To date, lupin allergy is suspected to be relatively uncommon in the overall German population since lupin sensitization occurred in only 2% of non-atopic subjects. However, there is a clear risk of a lupin allergy in predisposed subjects, since the frequency of lupin sensitization was 6% in atopic subjects. In particular, subjects with existing sensitization or allergy to other legumes are at higher risk for a sensitization or allergy to lupin due to cross-reactivity.

The effect of component-resolved diagnosis on specific immunotherapy prescription in children with hay fever

Sensitization to profilins and other cross-reacting molecules might hinder proper specific immunotherapy (SIT) prescription in polysensitized patients with pollen-related allergic rhinitis (AR). In these patients, component-resolved diagnosis (CRD) might modify SIT prescription by improving the identification of the disease-eliciting pollen sources. We sought to measure the effect of CRD on SIT prescription in children with pollen-related AR. Children (n = 651) with moderate-to-severe pollen-related AR were recruited between May 2009 and June 2011 in 16 Italian outpatient clinics. Skin prick test (SPT) reactivity to grass, cypress, olive, mugwort, pellitory, and/or Betulaceae pollen was considered clinically relevant if symptoms occurred during the corresponding peak pollen season. IgE sensitization to Phl p 1, Phl p 5, Bet v 1, Cup a 1, Art v 1, Ole e 1, Par j 2, and Phl p 12 (profilin) was measured by using ImmunoCAP. SIT prescription was modeled on SPT responses first and then remodeled considering also CRD according to GA(2)LEN-European Academy of Allergology and Clinical Immunology guidelines and the opinions of 14 pediatric allergists. No IgE to the respective major allergens was detected in significant proportions of patients with supposed clinically relevant sensitization to mugwort (45/65 [69%]), Betulaceae (146/252 [60%]), pellitory (78/257 [30%]), olive (111/390 [28%]), cypress (28/184 [15%]), and grass (56/568 [10%]). IgE to profilins, polcalcins, or both could justify 173 (37%) of 464 of these SPT reactions. After CRD, the SPT-based decision on SIT prescription or composition was changed in 277 (42%) of 651 or 315 (48%) of 651 children according to the European or American approach, respectively, and in 305 (47%) of 651 children according to the opinion of the 14 local pediatric allergists. In children with pollen-related AR, applying CRD leads to changes in a large proportion of SIT prescriptions as opposed to relying on clinical history and SPT alone. The hypothesis that CRD-guided prescription improves SIT efficacy deserves to be tested.

OX40 ligand: a potential costimulatory molecule in atopic asthma

Objective: We aimed to assess the percentage of peripheral blood B-lymphocytes expressing OX40 ligand (OX40L) in adult atopic and non-atopic asthmatic patients, and in healthy controls. Methods: This case–control study included 15 atopic asthmatic patients, 15 non-atopic asthmatic patients, and 15 healthy controls. Atopic status was determined by skin prick test reaction to the most common locally-encountered allergens. For all subjects, pulmonary function tests and measurement of total serum immunoglobulin E (IgE) levels by ELISA were performed. In addition, the percentage of B-lymphocytes expressing OX40L was assessed by flow cytometry in all three groups. Results: OX40L expression was significantly higher in atopic asthmatics than in non-atopic asthmatics and controls, but did not differ significantly between non-atopic asthmatics or controls. Among atopic asthmatics, OX40L expression correlated positively with total serum IgE levels, but not with age, disease duration, or values of forced expiratory volume in the first second. Conclusion: The over-expression of OX40L in atopic asthmatic patients appears to be linked to markers of the atopic status as total serum IgE, and signifies the vital role of OX40L in the atopic mechanism. Further large-scale studies are needed to investigate the role of OX40L in other atopic diseases and its relation to disease activity and severity.