A nationwide survey of inhalant allergens sensitization and levels of indoor major allergens in Korea

The Impact of Climate Change on the Sporulation of Atmospheric Fungi

The U.S. Global Change Research Program, Fourth National Climate Assessment reports that it is extremely likely that human activities, especially emissions of greenhouse gases, are the dominant cause of the observed warming since the mid-20th century. There are no convincing alternative explanations supported by observational evidence.

KOREAN AEROALLERGEN SENSITIZATION STATUS FROM 2018-2021

Objectives.

Studies on the aeroallergen sensitization status of South Koreans based on large-scale data are lacking.

Methods.

We analyzed data from 368,156 multiple allergosorbent tests collected by a domestic medical diagnosis company from 3,735 hospitals nationwide from 2018 to 2021. We additionally collected sex, age, and regional data. If the level of an aeroallergen was 0.35 IU/mL or more, the test result for that aeroallergen was defined as positive, and positive cases were defined as those where one aeroallergen was positive. The positive ratio (PR) for aeroallergens was calculated using positive cases.

Results.

In total, 347,996 cases were analyzed, excluding cases with missing data. The percentage of positive cases was 56.7%, which was highest in adolescents (74.1%) and lowest in the elderly (47.0%). All four types of mites had high PRs (0.382–0.655), and mold had low PRs (0.023–0.058). Among pollens, the PRs of grasses were generally high (more than 0.14), followed by weeds (approximately 0.10), and the PRs of woods was less than 0.1. For animals, cats and dogs had the highest PRs, at 0.231 and 0.183, respectively. The value for cockroaches was also high, at 0.211. The PRs of indoor aeroallergens, such as mites, molds, and animals, were high in adolescents, and those of pollen and cockroaches were high in the elderly. In Jeju, the PR of Japanese cedars was extremely high (0.222).

Conclusion.

Koreans were found to be sensitized to a wide variety of aeroallergens. There were significant differences in sensitization patterns according to age and region.

Concordance of skin test reactivity between indoor inhalant allergens among children with allergic respiratory disease

Background

In vitro studies have demonstrated cross-reactivity among indoor allergen proteins in children with allergic respiratory diseases. However, there are only few studies evaluating in vivo response. A skin prick test (SPT) with commercial indoor solutions is widely used in clinical practice. We aimed to evaluate SPT agreement in children with allergic respiratory disease between pairs of common indoor allergens.

Methods

We reviewed SPT results of children 2 to 18 years old, diagnosed with respiratory allergic disease. Results from house dust mite (Dermatophagoides farinae, Dermatophagoides pteronyssinus), cockroach (Periplaneta americana, Blatella germanica), cat and dog were collected. Sensitization was defined as ≥ 3 mm in wheal diameter. Kappa coefficient (κ) was used to analyze sensitization concordance for each allergen pair.

Results

The charts of 300 children, 187 (62.33%) males, were reviewed. Mean age was 7.43 ± 3.29 years with 183 (61%), 140 (46.67%), 45 (15%), 30 (10%) sensitizations to house dust mite (HDM), cockroach, cat and dog, respectively. Sensitization concordance between HDM and cockroach was moderate: κ = 0.53 (95% CI: 0.42–0.64). Moderate agreement occurred between dog and cat: κ = 0.41 (95%CI: 0.30–0.52). HDM-sensitized children showed poor concordance with both cat κ = 0.17 (95%CI: 0.09–0.24) and dog κ = 0.09 (95%CI: 0.03–0.14). There was also poor concordance between cockroach-sensitized children to cat κ = 0.19 (95%CI; 0.11–0.28) and dog κ = 0.11 (95%CI; 0.04–0.18).

Conclusion

We demonstrated moderate agreement of SPT response between HDM and cockroach as well as dog and cat. This may be due to cross-reactivity. Component-resolved diagnosis should be considered in children with co-sensitization of these allergen pairs.

Respiratory sensitization to insect allergens: Species, components and clinical symptoms

Airborne insect particles have been identified as an important cause of respiratory allergies, including allergic asthma and rhinitis. In the literature, the significance of respiratory exposure to insect particles as a cause of occupational allergy has been well-documented. Indeed, many cases of occupational allergy have been reported including allergy to the larvae of flies and moths in anglers and occupationally exposed workers, to grain pests in bakers or other workers handling grains, and to crickets and/or locusts in researchers and workers in aquaculture companies. Furthermore, the prevalence of sensitization to insect allergens is considerably high among patients with asthma and/or rhinitis who are not occupationally exposed to insects, suggesting the clinical relevance of exposure to insects in indoor and outdoor environmental non-occupational settings. Exposure to cockroaches, a well-studied indoor insect, is associated with cockroach sensitization and the development and exacerbation of asthma. Booklice, another common indoor insect, were recently identified as a significant sensitizer of asthmatic patients in Japan and India, and potentially of asthma patients living in warm and humid climates around the world. Lip b 1 was identified as an allergenic protein contributing to the species-specific sensitization to booklice. Moths are considered a significant seasonal outdoor allergen and their allergens are considered to have the highest sensitization rate among Japanese patients. However, other than cockroaches, allergenic insect proteins contributing to sensitization have not been fully characterized to date.

Differential Correlations among Allergy Tests According to Indoor Allergens in Allergic Rhinitis

OBJECTIVES

Several allergy tests are used for the diagnosis of allergic rhinitis; however, few studies have reported a direct comparison of the skin prick test (SPT), multiple allergen simultaneous test (MAST), and ImmunoCAP according to specific allergens. This study aimed to evaluate the correlations between each test and allergic rhinitis symptoms and to evaluate the correlations of the MAST and ImmunoCAP with the SPT for representative indoor allergens in Korea.

METHODS

Electronic medical charts were retrospectively reviewed, and 698 patients with allergic rhinitis who had performed SPT, MAST, and ImmunoCAP were enrolled. Correlations between each allergy test for 4 representative indoor allergens and the symptoms of allergic rhinitis were analyzed. Agreements of the MAST and ImmunoCAP with the SPT were compared according to each allergen.

RESULTS

The SPT showed higher correlations with allergic rhinitis symptoms for 4 indoor allergens (Dermatophagoides pteronyssinus, Dermatophagoides farinae, cat, and dog allergens) than the MAST or ImmunoCAP. In comparison between the MAST and SPT, the least correlation was observed for the dog allergen, whereas between the ImmunoCAP and SPT, the least correlation was observed for the cat allergen. The correlation between the ImmunoCAP and SPT was higher than that between the MAST and SPT for the dog allergen, whereas no significant differences were noted for other allergens.

CONCLUSIONS

Overall, the SPT showed a higher correlation with allergic rhinitis symptoms than the MAST or ImmunoCAP for 4 indoor allergens. ImmunoCAP showed similar reactivity to MAST; however, it showed better positivity with dog allergen in patients who were reactive to the allergen in the SPT. Care should be taken while evaluating dog allergen sensitization using the MAST.

Trends of Sensitization to Inhalant Allergens in Korean Children Over the Last 10 Years

PURPOSE

Climate and lifestyle changes increase an individual's susceptibility to various allergens and also the incidence of allergic diseases. We aimed to examine the changes in sensitization rate for aeroallergens over a 10-year period in Korean children.

MATERIALS AND METHODS

We retrospectively reviewed the medical records of 4493 children who visited the allergy clinic at a tertiary hospital in Korea for allergic rhinitis or asthma from January 2009 to December 2018. The serum specific immunoglobulin E (IgE) levels were measured to confirm the sensitization against Dermatophagoides farinae (D. farinae), Alternaria, weed and tree pollen mixtures, as well as cat and dog dander through ImmunoCAP test.

RESULTS

D. farinae was the most common sensitizing aeroallergen (45.9%) during the 10-year span. The sensitization rate for tree pollen mixture (p for trend <0.001), weed pollen mixtures (p for trend <0.001), dog dander (p for trend=0.025), and cat dander (p for trend=0.003) showed ascending trends during the 10-year study period. Furthermore, the sensitization rate for multiple allergens (≥2) in 2018 increased significantly compared to that in 2009 (p for trend=0.013). Compared with children without sensitization to D. farinae, those with sensitization to D. farinae showed higher sensitization rates to other aeroallergens (p for interaction <0.001).

CONCLUSION

Children's sensitization rate to cat and dog dander and weed and tree pollen mixtures significantly increased during the 10-year period in Korea. Children with sensitization to D. farinae are likely to be sensitized to other aeroallergens as well.

Sensitisation to aeroallergens in relation to asthma and other allergic diseases in Angolan children: a cross-sectional study

INTRODUCTION AND OBJECTIVES

In Africa, few studies of sensitisation profiles have been performed in children or adolescents and, in Angola, there are none. The objectives of the present study were to assess the sensitisation profile of Angolan schoolchildren and to determine the relationship between that pattern, sociodemographic factors, asthma and other allergic diseases.

MATERIALS AND METHODS

Cross-sectional, observational study in 5-14-year-old children, performed between September and November 2017, in the Province of Bengo, Angola. Five schools (15%) were randomly selected in the geographical area of the study: three from an urban area, and two from a rural area. Data were collected using the Portuguese versions of the ISAAC questionnaires for children and adolescents, regarding asthma, rhinitis and eczema. Skin prick tests (SPT) were performed with a battery of 12 aeroallergens. Stools were assessed for the presence of helminths. Descriptive statistics were used, as well as univariate calculation of odds ratios.

RESULTS

Sensitisation to aeroallergens was low (8%) and most sensitised children were asymptomatic. Most frequent sensitisations involved house dust mites, cockroach or fungi, and a high proportion of children (78.1%) were monosensitised. No relationship was detected between sensitisations and asthma, rhinitis or eczema. Place of residence, gender, age or helminthic infection did not affect the probability of having positive SPTs.

CONCLUSIONS

The most frequent sensitisations in children from Bengo Province in Angola involve house dust mites, followed by cockroach and fungi. No relationship was found between atopic sensitisation and asthma or other allergic diseases.

Trends in skin prick test according to seasons: Results of a Korean multi-center study

OBJECTIVE

Allergy is a very common condition. Allergic disease is highly affected by environmental changes. Conditions of the four seasons can change dramatically in Republic of Korea (ROK). To assess changes in rates of aeroallergen positivity according to seasons and environmental factors (temperature, humidity, and precipitation).

MATERIALS

A total of 20 hospitals were selected based on population distribution in ROK. A skin prick test (SPT) panel comprising 55 aeroallergens was distributed to 18 hospitals for a prospective study. Results from SPTs done in 2006 and 2010 were collected and analyzed retrospectively from 20 hospitals and 2014/2015 SPT (from June 2014 to May 2015) results from 18 hospitals were collected prospectively.

RESULTS

We compared allergen-positive rates among seasons. Positive test rates for several pollens and house dust mites increased significantly in spring and fall. Pollens positive rate varied significantly according to temperature, precipitation, and humidity while mite allergens were less susceptible to environment.

CONCLUSION

There are four distinct seasons in ROK. The positivity of pollen allergens were especially affected by temperature and precipitation in spring. House dust mites were less affected by seasons, temperature, precipitation, and humidity less than pollen. Therefore, regular follow-up and re-evaluation of allergic test are essential considering changes of seasons and environment for acceptable diagnosis and treatment.

Effects of Vacuuming Mattresses on Allergic Rhinitis Symptoms in Children

PURPOSE

To evaluate the effects of daily vacuuming of mattresses on the concentration of house dust mite (HDM) allergens and on allergic rhinitis (AR) symptoms in children sensitized to HDM.

METHODS

Forty children between the ages of 6 and 12 years with mild persistent AR and sensitized only to HDM were enrolled and randomly allocated to 2 groups. Caregivers of children in the experimental group cleaned the children's rooms and vacuumed their mattresses daily for 2 weeks. Caregivers of children in the control group cleaned the children's rooms without vacuuming mattresses. Symptoms of AR were checked weekly and dust samples were collected from the mattresses before and after the study.

RESULTS

Demographics at the beginning of the study were not significantly different between the 2 groups. In the experimental group, symptoms of AR and dust weight were significantly decreased after 2 weeks (total symptoms of AR, P <0.001; sneezing, P < 0.001; rhinorrhea, P <0.001; nasal obstruction, P < 0.001; itching, P <0.001; and dust weight, P = 0.006). The concentrations of HDM allergens were not changed significantly (Der p1, P = 0.333; Der f1, P = 0.841). In the control group, there were no significant changes in symptoms of AR, dust weight, or the concentration of HDM allergens.

CONCLUSIONS

Our findings showed that daily vacuuming of mattresses reduced dust weight and symptoms of AR. However, the concentration of HDM allergens did not significantly decrease.

Neutrophil oxidative burst as a diagnostic indicator of IgG-mediated anaphylaxis

Background

IgG-mediated anaphylaxis occurs after infusion of certain monoclonal antibody-based therapeutics. New in vitro tests are urgently needed to diagnose such reactions. We investigated whether allergens trigger neutrophil oxidative burst (OB) and if neutrophil OB occurs due to allergen-specific IgG (sIgG).

Methods

Neutrophil OB was measured by dihydrorhodamine 123 flow cytometry using a leukocyte suspension spiked with a very small patch of the allergen crude extract, Dermatophagoides farinae (Der f). The mean fluorescence intensity ratio of stimulated to unstimulated samples was calculated as the neutrophil oxidative index (NOI).

Results

The Der f-specific NOI (Der f-sNOI) showed a time-dependent increase after Der f extract addition. At 15 min activation, higher Der f-sIgG levels were associated with lower Der f-sNOI values in 31 subjects (P<0.05). This inverse relationship occurs due to the initial blocking effect of free Der f-sIgG. Additionally, neutrophil OB was nearly absent (Der f-sNOI of -1) in two cases: a subject with undetectable Der f-sIgG levels and washed leukocyte suspensions deprived of Der f-sIgG.

Conclusion

Allergens can trigger neutrophil OB via preexisting allergen-sIgG. Neutrophil OB can be easily measured in a leukocyte suspension spiked with the allergen. This assay can be used to diagnose IgG-mediated anaphylaxis.

Comparison of allergen-specific IgE levels between Immulite 2000 and ImmunoCAP systems against six inhalant allergens and ten food allergens

In vitro allergen-specific immunoglobulin E (sIgE) measurement has been used as an important diagnostic tool for allergic diseases. Currently, quantitative sIgE levels are detected mainly by using ImmunoCAP and Immulite 2000 assay system. These two systems have the same calibration scale at 0-100 kUA/L, but they differ in used allergens, detection methods and automation systems. We compared 1600 paired sIgE results for 204 allergic patients, including 100 paired sIgE assay results for each of 16 allergens (Alternaria alternata, birch-alder mix, cat dander, D. farinae, D. pteronyssinus, dog dander, buckwheat, crab, egg white, mackerel, milk, peach, peanut, shrimp, soybean and wheat flour). Inter-method comparison was performed for qualitative data with a cutoff of 0.35 kUA/L and a detection limit of 0.1 kUA/L, semi-quantitative class results and quantitative data. In qualitative comparisons, the overall concordance rate ranged from 81.0% to 99.0% (k: 0.599-0.949) with the cutoff value of 0.35 kUA/L. It also ranged from 80.0% to 99.0% (k: 0.521-0.951) with the detection limit of 0.1 kUA/L. The class results from these two assays showed good agreements for all allergens. For quantitative sIgE results, these two assays showed moderate positive correlations for Dog dander (r = 0.683) and Mackerel (r = 0.573) but high to very high correlations for the other 14 allergens (r = 0.734-0.972). Immulite 2000 and ImmunoCAP assays demonstrated good concordance and correlation for 16 common allergens, but international standards against each specific allergen for calibration and harmonization of sIgE tests are still needed.

Allergen Microarrays for In Vitro Diagnostics of Allergies: Comparison with ImmunoCAP and AdvanSure

BACKGROUND

In vitro detection of the allergen-specific IgE antibody (sIgE) is a useful tool for the diagnosis and treatment of allergies. Although multiple simultaneous allergen tests offer simple and low-cost screening methods, these platforms also have limitations with respect to multiplexibility and analytical performance. As an alternative assay platform, we developed and validated a microarray using allergen extracts that we termed "GOLD" chip.

METHODS

Serum samples of 150 allergic rhinitis patients were used in the study, and the diagnostic performance of the microarray was compared with that of AdvanSure (LG Life Sciences, Daejun, Korea) and ImmunoCAP (Phadia, Uppsala, Sweden). Standard IgE samples were used for the quantitative measurement of sIgEs.

RESULTS

The microarray-based assay showed excellent performance in the quantitative measurement of sIgEs, demonstrating a linear correlation within the range of sIgE concentrations tested. The limit of detection (LOD) was lower than 0.35 IU/mL, which is the current standard for the LOD cut-off. The assay also provided highly reproducible sets of data. The total agreement percentage of positive and negative calls was 92.2% compared with ImmunoCAP. Moreover, an outstanding correlation was observed between the microarray and the ImmunoCAP results, with Cohen's kappa and Pearson correlation coefficient values of 0.80 and 0.79, respectively.

CONCLUSIONS

The microarray-based in vitro diagnostic platform offers a sensitive, reproducible, and highly quantitative method to detect sIgEs. The results showed strong correlations with that of ImmunoCAP. These results suggest that the new allergen microarray can serve as a useful alternative to current screening platforms, ultimately becoming a first-line screening method.

Comparison between Newly Developed and Commercial Inhalant Skin Prick Test Reagents Using In Vivo and In Vitro Methods

BACKGROUND

We developed skin prick test (SPT) reagents for common inhalant allergens that reflected the real exposure in Korea. The study aim was to evaluate diagnostic usefulness and allergen potency of our inhalant SPT reagents in comparison with commercial products.

METHODS

We produced eight common inhalant allergen SPT reagents using total extract (Prolagen): Dermatophagoides farinae, Dermatophagoides pteronyssinus, oak, ragweed, mugwort, Humulus japonicus pollens, as well as cat and dog allergens. We compared the newly developed reagents with three commercially available SPT reagents (Allergopharma, Hollister-Stier, Lofarma). We measured total protein concentrations, sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE), major allergen concentration, and biological allergen potencies measured by immunoglobulin E (IgE) immunoblotting and ImmunoCAP inhibition test.

RESULTS

Diagnostic values of these SPT reagents were expressed as positivity rate and concordance rate of the results from ImmunoCAP allergen-specific IgE test in 94 allergic patients. In vitro analysis showed marked differences in protein concentrations, SDS-PAGE features, major allergen concentrations, and biological allergen potencies of four different SPT reagents. In vivo analysis showed that positive rates and concordance rates of Prolagen® SPT reagents were similar compared to the three commercial SPT reagents.

CONCLUSION

The newly developed Prolagen® inhalant SPT reagents are not inferior to the commercially available SPT reagents in allergy diagnosis.

House dust mite and Cockroach specific Immunoglobulin E sensitization is associated with diabetes mellitus in the adult Korean population

Immunoglobulin E (IgE) is known to activate mast cells. Prior studies have shown that mast cells contribute to diet-induced obesity and diabetes mellitus (DM). We aimed to determine whether adults with IgE sensitization were at risk of DM. We performed assays regarding serum total IgE and allergen-specific IgE levels against the house dust mite, the cockroach, and the dog on 1,528 adults randomly sampled from every age and gender group in various districts. The total and three allergen-specific IgE levels were positively correlated with fasting glucose level and insulin resistance. Subjects with increased levels of total IgE (>100 kU/L), compared to those without, had an odds ratio (OR) of 1.72 (95% confidence interval [95% CI], 1.17–2.54) for DM after adjusting for various covariates. Further controlling for previous allergic disease did not attenuate the association between total IgE level and DM. Subjects sensitized to the house dust mite (OR 1.63, 95% CI, 1.03–2.59) and the cockroach (OR 2.27, 95% CI, 1.40–3.66) were also at increased risk of DM. We found a strong positive association between IgE sensitization and DM in a general Korean population, suggesting that IgE may be an important independent risk factor for metabolic diseases in Koreans.

Distinct epitope structures of defensin-like proteins linked to proline-rich regions give rise to differences in their allergenic activity

Background

Art v 1, Amb a 4, and Par h 1 are allergenic defensin‐polyproline–linked proteins present in mugwort, ragweed, and feverfew pollen, respectively. We aimed to investigate the physicochemical and immunological features underlying the different allergenic capacities of those allergens.

Methods

Recombinant defensin‐polyproline–linked proteins were expressed in E. coli and physicochemically characterized in detail regarding identity, secondary structure, and aggregation status. Allergenic activity was assessed by mediator releases assay, serum IgE reactivity, and IgE inhibition ELISA using sera of patients from Austria, Canada, and Korea. Endolysosomal protein degradation and T‐cell cross‐reactivity were studied in vitro.

Results

Despite variations in the proline‐rich region, similar secondary structure elements were observed in the defensin‐like domains. Seventy‐four percent and 52% of the Austrian and Canadian patients reacted to all three allergens, while Korean patients were almost exclusively sensitized to Art v 1. This was reflected by IgE inhibition assays demonstrating high cross‐reactivity for Austrian, medium for Canadian, and low for Korean sera. In a subgroup of patients, IgE reactivity toward structurally altered Amb a 4 and Par h 1 was not changed suggesting involvement of linear epitopes. Immunologically relevant endolysosomal stability of the defensin‐like domain was limited to Art v 1 and no T‐cell cross‐reactivity with Art v 1_25‐36 was observed.

Conclusions

Despite structural similarity, different IgE‐binding profiles and proteolytic processing impacted the allergenic capacity of defensin‐polyproline–linked molecules. Based on the fact that Amb a 4 demonstrated distinct IgE‐binding epitopes, we suggest inclusion in molecule‐based allergy diagnosis.

Comparison of Singleplex Specific IgE Detection Immunoassays: ImmunoCAP Phadia 250 and Immulite 2000 3gAllergy

BACKGROUND

The identification of clinically meaningful specific immunoglobulin E (sIgE) is important for the diagnosis and management of allergic diseases. Various in vitro sIgE detection methods are available worldwide. Depending on the number of antigens that can be tested simultaneously, there are two representative methods: singleplex and multiplex. Singleplex sIgE detection is mainly provided by Thermo Fisher (ImmunoCAP) and Siemens (Immulite). This study aimed to compare the diagnostic agreement of two singleplex sIgE detection assays.

METHODS

Sera from 209 Korean patients with allergic disease were used to compare the ImmunoCAP and Immulite assays with respect to the following allergens: inhalant allergens (Dermatophagoides farinae, cat and dog dander, oak, rye grass, mugwort, Alternaria, German cockroach) and food allergens (hen's egg white, cow's milk, wheat, peanut, soybean, and shrimp). Data from 902 paired comparison tests were included for comparisons. Qualitative, semi-quantitative, and quantitative comparisons were performed using statistical analyses.

RESULTS

In qualitative comparisons, the positivity and negativity agreements ranged from 75% (wheat, shrimp) to 96% (Alternaria). Class consistency (classes 0-6) was well matched. Spearman's rank correlation coefficients for all allergens except shrimp were over 0.7. In quantitative comparisons, all allergens excluding shrimp showed >0.7 intra-class correlation coefficients.

CONCLUSIONS

The ImmunoCAP and Immulite systems showed similar performances. However, clinicians should consider fundamental methodological differences between the assays.

Effectiveness of proton pump inhibitor in unexplained chronic cough

Background

Current guidelines recommend that patients with unexplained chronic cough undergo empirical proton pump inhibitor (PPI) treatment, but scientific evidence for this treatment is lacking. We investigated the effectiveness and appropriate dose of PPI therapy in chronic cough.

Methods

We included 27 patients with unexplained chronic cough after excluding subjects with positive response to postnasal drip medication. Subjects were randomized to a placebo, standard, and high dose of PPI groups with blinding. The drug or placebo was administered orally for 8 weeks, and the Leicester Cough Questionnaire (LCQ) score and visual analogue scale (VAS) scores were collected.

Results

The LCQ score in the PPI group significantly improved from 0 weeks (11.4 ± 1.4) to 4 weeks (14.8 ± 1.4) and to 8 weeks (17.1 ± 1.4), whereas that in the placebo group did not improve from 0 weeks (13.7 ± 1.1) to 8 weeks (11.8 ± 1.4); the difference between the 2 groups was significant (P < 0.001). In subgroup analysis according to reflux, significant improvements in the LCQ score were observed in the PPI group regardless of reflux (P < 0.001 in the reflux group and P < 0.001 in the no reflux group, respectively; P = 0.188 between the 2 groups). In addition, improvements in LCQ and VAS scores between the standard- and high-dose PPI groups were not significantly different; however, adverse reactions were induced by only the high dose (16.7%).

Conclusions

The results of this pilot study support the empirical use of the standard dose of PPI for 8 weeks in patients suffering from unexplained chronic cough regardless of whether reflux is present.

Trial registration

ClinicalTrial.gov NCT01888549 www.clinicaltrials.gov; cris.nih.go.kr KCT0000543 cris.nih.go.kr/

Sensitization patterns and minimum screening panels for aeroallergens in self-reported allergic rhinitis in China

Optimization of skin prick test (SPT) panels, especially in view of significant differences in sensitizations patterns within different geographical areas, is an unmet need within China. Our aim was to assess the patterns and clinical relevance of aeroallergen sensitizations in allergic rhinitis (AR) and define the minimal battery of SPT allergens, classified according to the Köppen-Geiger climate map. Overall, 7148 subjects with self-reported AR completed a standard questionnaire and were assessed for sensitization to relevant allergens by SPT. 6340 (88.7%) patients had at least one positive skin prick reaction, and demonstrated unique sensitization patterns by stratification with age, gender, and geographic region. Sensitization to house dust mites (HDM) was highest in south China, whereas the three most prevalent aeroallergens were mugwort, ragweed and dandelion pollen in north-west China. Higher sensitization rates and multiple sensitizations were associated with AR comorbidities. Eight allergens (Der f, mugwort, Blatella, hazel, goosefoot, Penicillium notatum, animal dander and Der p) allowed identification >96% of sensitized subjects in central China. Differences in optimal panels were observed between regions, with five to six allergens being sufficient for north-east, north-west and south China. These SPT panels may provide a cost-effective tool for screening sensitized patients in China.

Comparison between skin prick test and serum immunoglobulin E by CAP system to inhalant allergens

BACKGROUND

Skin prick tests (SPTs) and measurements of serum specific immunoglobulin E (sIgE) antibodies are the most commonly used diagnostic tools for confirming sensitization. However, disagreement between the tests has been observed.

OBJECTIVE

To compare SPT and the CAP system for diagnosis of sensitization to common inhalant allergens.

METHODS

Subjects included 2,635 patients 10 to 90 years old who underwent analyses by SPT and CAP at the Dong-A University Hospital (Busan, Korea) from June 2011 through May 2016. The 2 test results were compared for 17 inhalant allergens.

RESULTS

Agreement between the SPT and sIgE level was 75.3%. Overall agreement was moderate (κ = 0.59), with strong agreement for house dust mites and birch (κ > 0.7) and weak agreement for Tyrophagus putrescentiae and dog (κ < 0.3). When CAP was compared with SPT as the reference, the sensitivity was 75.8% and the specificity was 75.2%. Mean wheal size by SPT showed a positive correlation with sIgE levels (r = 0.59), which decreased with age.

CONCLUSION

There was a discrepancy between SPT and CAP for diagnosing allergic sensitization among inhalant allergens. The allergic sensitization and correlation between the tests decreased with age. Cautious interpretation of the clinical relevance of allergen sensitization based on SPT and CAP results is required, especially in older patients.

Regional Difference of Causative Pollen in Children with Allergic Rhinitis

The aim of this study was to investigate role of common pollen in Korean school-aged children with allergic rhinitis (AR) in 5 provinces (Incheon Metropolitan City-Gyeonggi Province, Chungcheongbuk-do, Gwangju Metropolitan City, Busan Metropolitan City, and Jeju Special Self-Governing Province), using a questionnaire and skin prick test, and to assess the differences among the residential regions. Among the enrolled 14,678 total children, 1,641 (22.0%) had AR. The sensitization rate to pollen (38.7%) was the second highest among examined allergens and significant differences were in the sensitization rates to trees, weeds, and grasses among the 5 provinces (P < 0.05). The sensitization to trees (25.2%) was the highest common among the pollen types and significant differences also were observed in the sensitization rates to alder, birch, Japanese cedar, oak, and elm among the 5 provinces. The sensitization rate to weeds (19.9%) was the second highest and significant differences were observed in the sensitization rate to Japanese hop, mugwort, and ragweed among the 5 provinces. The sensitization rate to house dust mite was 86.8%, the highest among examined allergens and that to Dermatophagoides farinae exhibited regional differences (P = 0.003) but not to D. farinae (P = 0.584). The sensitization rate to mold (13.5%) was the highest in Jeju and lowest in Busan, and a statistically significant difference was detected among the 5 provinces. These results support that examined pollen allergens are strongly associated with residential region due to regional causative pollen differences among children with AR within Korea to investigate the main pollen allergens.

Association between Cockroach-specific Immunoglobulin E and periodontitis in Korean male adults Based on Korean National Health and Nutrition Examination Survey

Periodontitis is an inflammatory disease affecting the tooth supporting tissues (periodontium) and associated with chronic diseases such as cardiovascular disease and insulin resistance. However, there has been no nation-wide population based epidemiologic study regarding any association between periodontitis and serum IgE. Among the 8,958 participants in the 2010 Korean National Health and Nutrition Examination Survey (KNHANES V-1), 1,731 adults aged 19 to 64 who had measured serum IgE were included in the analysis. Dentists examined the periodontal status of the participants. Multiple logistic regression analyses were used to evaluate the odds ratio of periodontitis in association with total IgE and specific IgE to cockroach and house dust mite. In males, total IgE showed a positive correlation with the presence of periodontitis. The participants in the highest tertile of cockroach specific IgE (T3, >31.6 kU/L) had a significantly increased risk of periodontitis (OR = 2.108; 95% CI, 1.233–3.606). In females, the inverse association occurred between total IgE and periodontitis (OR = 0.409; 95% CI, 0.200–0.839). The present study firstly demonstrated the association between periodontitis and serum IgE, using the Korean nationwide, population-based, cross-sectional health examination and survey. This study suggested a positive correlation between periodontitis and cockroach-specific IgE in Korean male adults.

Dermatophagoides pteronyssinus: Changes in sensitisation in the past 11 years and comparison with other centres in Mexico

BACKGROUND

House dust mites are a ubiquitous air allergen in the human habitat. It has been shown that exposure to them is a fundamental factor in sensitisation and development of atopic disease. The objective of the study was to analyse changes in sensitisation to Dermatophagoides pteronyssinus (Der p.) in children treated in a tertiary level care hospital in Mexico City for a period of 11 years and compare with other studies carried out in Mexico.

METHODS

A retrospective study was performed at the Hospital Infantil de México Federico Gómez (HIMFG). Information was gathered from skin tests for Der p. performed in the Allergy Laboratory from January 2004 to April 2015. Patients 2-18 years old who presented for examination of some type of allergic condition and who had immediate hypersensitivity tests to Der p. were included in the study. Results were compared with prior reports from other institutions. Descriptive analysis and χ² statistics were used.

RESULTS

A total of 8794 patients were included in the study; 49.3% of the tests (95% CI 48-50) were positive for Der p. The percentage of monosensitised to mites was 2.7% for Der p. (95% CI 2-3). A significant difference was found between the results of older patients and those <6 years old. The frequency of sensitisation had a tendency to decrease during the 11 years analysed in all age groups.

CONCLUSIONS AND CLINICAL RELEVANCE

The frequency of sensitisation to Der p. increased with age until reaching adolescence. In the last 11 years a decrease in sensitisation to this air allergen was observed.

Patterns of Inhalant Allergen Sensitization and Geographical Variation in Korean Adults: A Multicenter Retrospective Study

Purpose

Inhalant allergen sensitization is one of the major factors involved in the pathogenesis of allergic respiratory diseases. However, the sensitization is determined by interactions between genetic and environmental factors. Thus, testing panels of inhalant allergens may differ among geographical areas. Here we aimed to determine 10 common inhalant allergens in Korean adult patients with suspected respiratory allergies and to examine the variation between different geographical locations.

Methods

A total of 28,954 patient records were retrieved for retrospective analysis, from 12 referral allergy clinics located in 9 different areas. Inclusion criteria were Korean adults (≥18 years old) who underwent the inhalant allergen skin prick test for suspected history of respiratory allergy. The primary outcome was inhalant allergen skin prick response. Demographic and clinical information were also collected. Positive skin prick responses to allergens were defined as allergen-to-histamine wheal ratio ≥1. Based on skin test results, the most prevalent aeroallergens were determined.

Results

The overall prevalence of allergic sensitization was 45.3%. Dermatophagoides farinae and Dermatophagoides pteronyssinus were the most commonly sensitized allergens. Other common inhalant allergens were cat epithelium (8.1%), birch (7.7%), mugwort (6.9%), alder (6.7%), hazel (6.7%), beech (6.7%), oak (6.6%), and Tyrophagus putres (6.2%), in decreasing order frequency. These 10 inhalant allergens explained 90% of inhalant allergen sensitization in the study participants. However, distinct patterns of the 10 inhalant sensitization were observed in patients living in Chungnam and Jeju. American cockroach, Gernam cockroach, and Trichophyton metagrophytes were unique in Chungnam. Orchard, Japanese cedar, and Velvet were unique in Jeju.

Conclusions

The present analysis suggests a panel of 10 most common inhalant allergens in Korean adult patients with suspected respiratory allergies, which explained 90% of inhalant allergen sensitization. This panel can be utilized as a practical and convenient tool for primary practice and epidemiological surveys of respiratory allergic diseases.

Different Responses in Induction of Allergen Specific Immunoglobulin G4 and IgE-Blocking Factors for Three Mite Subcutaneous Immunotherapy Products

PURPOSE

Specific immunoglobulin G4 (sIgG4) and immunoglobulin E (IgE)-blocking factors produced by subcutaneous immunotherapy (SCIT) play a critical role in the induction of allergen tolerance. However, comparative studies of available SCIT reagents on the induction of sIgG4 are limited. We compared increases in sIgG4 for three different house dust mite (HDM) SCIT reagents.

MATERIALS AND METHODS

Seventy-two HDM sensitized allergic patients were enrolled and classified into four groups: 1) control (n=27), 2) SCIT with Hollister-Stier® (n=19), 3) Tyrosine S® (n=16), and 4) Novo-Helisen® (n=10). Levels of specific IgE (sIgE), sIgG4, and IgE blocking factor to Dermatophagoides farinae (D. farinae) were measured using ImmunoCAP (sIgE, sIgG4) and enzyme-linked immunosorbent assay (ELISA) (IgE-blocking factors). Levels were measured before and 13.9±6.6 months after the SCIT. The allergen specificity and the induction levels of sIgE and sIgG4 were confirmed by immunoblot analysis.

RESULTS

After SCIT, sIgG4 levels to D. farinae increased significantly; however, the increases differed significantly among the SCIT groups (p<0.001). Specific IgG4 levels to D. farinae were highest in Hollister-Stier® (3.7±4.1 mg/L), followed by Novo-Helisen® (2.2±2.3 mg/L) and Tyrosine S® (0.7±0.5 mg/L). In addition, patients who were administered using Hollister-Stier® showed the most significant decrease in IgE/IgG4 ratio (p<0.001) and increase in blocking factor (p=0.009). Finally, according to IgE immunoblot results, the Hollister-Stier® group showed the most significant attenuation of IgE binding patterns among others.

CONCLUSION

Currently available SCIT reagents induce different levels of specific IgG4, IgE/IgG4 ratio, and IgE-blocking factor.

Association of body mass index and other factors with histamine skin reactivity in adults with allergic nasal symptoms

BACKGROUND

The skin-prick test is the most commonly used method to diagnose allergy. In addition, histamine skin reactivity is used as a positive control for the skin-prick test. However, there is individual variation in histamine skin reactivity. The factors that influence individual variation in histamine skin reactivity remain unknown.

OBJECTIVES

We aimed to investigate the factors associated with histamine skin reaction.

METHODS

Ninety-seven subjects who underwent a skin-prick test to diagnose allergic rhinitis were enrolled in this study. The skin-prick test was performed with six common allergens. The wheal size of the histamine skin reaction was analyzed; other variables included age, sex, body mass index (BMI), atopy, smoking history, and the testing season.

RESULTS

The wheal size in the histamine skin test was significantly associated with age and BMI. The association between histamine skin reactivity and BMI was also present in multivariate analysis, adjusted for age, sex, atopy, smoking history, and season.

CONCLUSION

Histamine skin reactivity increased with BMI (degree of obesity). This association should be considered for better interpretation of the skin-prick test. Further studies regarding the mechanism for this association are needed.

Cross-Reactivity between Oak and Birch Pollens in Korean Tree Pollinosis

Oak and birch trees belong to Fagales order. Specific IgE to pollen allergens of both trees are frequently found in Korea pollinosis patients. Oak trees which comprise 40% of forest area are common in Korea. However, birch trees are sparse. We compared the allergenicity of pollen extracts of white oak, sawtooth and Mongolian oaks which are prevalent species in Korea, with the pollen extract of birch. The cross-reactivity of four pollen extracts was examined with pooled sera of 12 patients by ELISA, immunoblotting and CAP inhibitions. A protein of 17 kDa, putatively homologous to a major birch allergen Bet v 1, displayed strong IgE reactivity from white oak and sawtooth oak pollen extract but not from Mongolian oak pollen. Notably, a 23-kDa protein from sawtooth and white oaks showed strong IgE reactivity and inhibited by Bet v 1. IgE binding to white oak was inhibited a maximum of 94.6% by white oak, 93.4% by sawtooth oak, 83.2% by Mongolian oak, and 68.8% by birch. Furthermore, sawtooth oak, white oak, and Mongolian oak extracts were able to inhibit up to 78.5%, 76.6% and 67.3% of IgE binding to birch extract, while birch extract itself inhibited up to 94.3%. Specific IgE to Bet v 1 was inhibited a maximum of 79.1% by sawtooth oak, 77.4% by white oak, and 72.7% by Mongolian oak, while 81.5% inhibition was shown by birch. Bet v 1 was able to partially inhibit its homologous molecules from sawtooth oak and white oak in immunoblotting. Birch pollen extract was found to be cross-reactive primarily with Bet v 1-homologous allergen from oak pollens in Korea pollinosis patients. Considering the sparseness of birch tree in Korea, oak, especially sawtooth oak may be the main cause of tree pollinosis in Korea, rather than birch.

Nasal provocation test is useful for discriminating allergic, nonallergic, and local allergic rhinitis

BACKGROUND

No standard study protocol or diagnostic criteria based on nasal provocation test (NPT) and acoustic rhinometry (AR) results are available for allergic rhinitis.

OBJECTIVE

We aimed to evaluate the usefulness of NPT plus AR for the differential diagnosis of local allergic rhinitis (LAR), allergic, and nonallergic rhinitis.

METHODS

The medical records and skin-prick test (SPT) and NPT results of 262 patients with symptoms of chronic rhinitis were reviewed. Patients were allocated to one of three groups, that is, group A [n = 110, negative SPT result for Dermatophagoides pteronyssinus (DP)], group B (n = 53, weakly positive result), or group C (n = 99, strongly positive result).

RESULTS

Twelve patients had a negative SPT result and provoked response in NPT [≥29% decrease of minimal cross-sectional area (MCA) after DP challenge] were diagnosed to have LAR. After DP challenge, group C showed significant aggravation of nasal symptoms and a greater decrease in acoustic parameters than groups A and B (p < 0.01). In patients with a more than or equal to 2 visual analog scale (VAS) increase in nasal obstruction (NO) after DP challenge, the criterion "a change of total nasal symptom score (TNSS) of more than or equal to 6.5" had 90.6% sensitivity and 77.4% specificity for the diagnosis of allergic rhinitis, whereas the diagnostic criterion "a total nasal volume (TNV) change at 30 minutes after DP challenge of more than or equal to 27.6%" had 73.4% sensitivity and 58.1% specificity.

CONCLUSION

NPT with AR could be a useful tool for the differential diagnosis of allergic, nonallergic, and local allergic rhinitis.

Cat (Fel d 1) and dog (Can f 1) allergen levels in cars, dwellings and schools

Pets are an important source of indoor allergens. The aim of the study was to compare cat and dog allergen levels in cars, schools and homes. The study was carried out in 17 cars, 14 classrooms and 19 dwellings located in the highly industrialized and urbanized region of Poland. Dust and air samples were analyzed for Fel d 1 and Can f 1 using a double monoclonal ELISA assay. The highest amounts of cat and dog allergens (Fel d 1: 1169 μg/g; Can f 1: 277 μg/g) were found in dwellings with pets. Allergen concentrations were correlated with the number of animals kept at home. Although concentrations on automobile seats were lower, Fel d 1 levels exceeded 8 μg/g in 23.5 % of cars and high levels of Can f 1 (>10 μg/g) were found in 17.6 % of cars. The study revealed that cars of pet owners may be reservoirs of cat and dog allergens even when animals are not transported in them. In schools, concentrations of pet allergens did not reach high levels, but the moderate levels of Fel d 1 (≥1-8 μg/g) and Can f 1 (≥2-10 μg/g) were detected in 42.9 and 7.1 % of the investigated classrooms. Concentrations of cat and dog allergen in schools were higher than in homes without pets. While airborne Fel d 1 and Can f 1 levels were found low, residential allergen concentrations in settled dust and air were correlated. The study results suggest that classrooms and cars of pet owners may be important sites of exposure to cat and dog allergens, though the highest concentrations of Fel d 1 and Can f 1 are found in homes of pet owners.

Standardization of Weed Pollen Extracts, Japanese Hop and Mugwort, in Korea

PURPOSE

Japanese hop (Humulus spp.) and mugwort (Artemisia spp.) are notable causes of autumn pollinosis in East Asia. However, Japanese hop and mugwort pollen extracts, which are widely used for the diagnosis, have not been standardized. This study was performed to standardize Japanese hop and mugwort pollen extracts.

MATERIALS AND METHODS

Allergen extracts were prepared in a standardized way using locally collected Humulus japonicus and purchased Artemisia vulgaris pollens. The immunoglobulin E (IgE) reactivities of prepared extracts were compared with commercial extracts via IgE immunoblotting and inhibition analyses. Intradermal skin tests were performed to determine the bioequivalent allergy unit (BAU).

RESULTS

The IgE reactive components of the extracts via IgE immunoblotting were similar to those of commercial extracts. A 11-kDa allergen showed the strongest IgE reactivity in Japanese hop, as did a 28-kDa allergen in mugwort pollen extracts. Allergenic potencies of the investigatory Japanese hop and mugwort extracts were essentially indistinguishable from the commercial ones. Sums of erythema of 50 mm by the intradermal skin test (ΣED50) were calculated to be 14.4th and 13.6th three-fold dilutions for Japanese hop and mugwort extracts, respectively. Therefore, the allergenic activity of the prepared extracts was 90827.4 BAU/mg for Japanese hop and 34412 BAU/mg for mugwort.

CONCLUSION

We produced Japanese hop and mugwort pollen extracts using a standardized method. Standardized Japanese hop and mugwort pollen extracts will facilitate the production of improved diagnostic and immunotherapeutic reagents.

CpG Oligodeoxynucleotide Inhibits Cockroach-Induced Asthma via Induction of IFN-γ⁺ Th1 Cells or Foxp3⁺ Regulatory T Cells in the Lung

Purpose

CpG oligodeoxynucleotide (CpG-ODN), a TLR9 agonist, activates innate immunity and induces Th1 response. Although the immune modulatory effect of CpG-ODN has been extensively studied, its function in cockroach extract-induced allergic asthma has not been studied. Here, we investigated the inhibitory function of CpG-ODN in cockroach extract-induced asthma in mice with different treatment schemes.

Methods

Scheme 1: BALB/C mice were intra-nasally co-administered by cockroach extract and CpG-ODN twice a week for 3 weeks; Scheme 2: The mice were intra-nasally pre-treated with CpG-ODN at day 0 and cockroach allergen challenge was performed from day 3 as in scheme 1. Scheme 3: Cockroach allergen challenge was performed as in scheme 1 and CpG-ODN was post-treated at day 21. Then, BAL cell count, flow cytometric analysis of alveolar macrophages, regulatory T cells, and lung tissue histology, Th1 and Th2 cytokines, serum IgE, cockroach specific IgE, IgG1/IgG2a ratio, and airway hyper-responsiveness were evaluated.

Results

Mice with repeated intra-nasal exposure to CpG-ODN showed a dramatic decrease in eosinophilic inflammation, goblet cell hyperplasia, and airway hyper-responsiveness with reduction of IL-13, IL-5, and serum IgE, cockroach specific IgE and IgG1/IgG2a ratio. This inhibitory function might be related to the up-regulation of IL-10 and CD4⁺Foxp3⁺ regulatory T cells in the lung. Interestingly, one-time challenge of CpG-ODN either prior or posterior to cockroach extract exposure could modulate airway inflammation and hyper-responsiveness via increase of Th1 response.

Conclusions

Collectively, our data suggest that CpG-ODN treatment modulates Th2 inflammation in the lung by induction of regulatory T cells or Th1 response in a cockroach-induced asthma model.

Dog allergen immunotherapy: past, present, and future

OBJECTIVE

To review the published medical literature on dog allergy immunotherapy and discuss prior clinical trials, important allergens, extract specifics, and potential future treatment options for dog allergy relevant to the clinical allergist.

DATA SOURCES

MEDLINE search was performed using the terms dog, immunotherapy, and allergy limited to human studies from any period. Articles cited in selected studies also were reviewed for appropriateness of inclusion into this review.

STUDY SELECTIONS

Publications were included that were original research and fit the topic of dog allergen immunotherapy, specifically articles that investigated prior effectiveness and safety of dog allergen immunotherapy, dog extracts, identification of dog allergens, and current prescribing trends among allergists.

RESULTS

Two hundred fifteen articles were initially identified and 60 were reviewed in complete detail for inclusion in this review. The primary focus was placed on the 17 clinical trials that investigated the safety and efficacy of dog immunotherapy and the 19 studies that explored and defined the complex allergenic profile of dog extracts.

CONCLUSION

The medical literature on the use of dog extract immunotherapy in patients with hypersensitivity to dog shows poor and conflicting results of clinical efficacy, which has been attributed to poor-quality extracts and the inherent complex allergenic profile of dogs that remains without a clearly dominant allergen.

Prevalence of Atopic Dermatitis in Korean Children Based on Data From the 2008-2011 Korean National Health and Nutrition Examination Survey

Population-based studies of atopic dermatitis (AD) in Korean children are lacking. Thus, the purpose of this study was to determine the prevalence, geographic distribution, and risk factors of AD in the Korean pediatric population. We examined AD prevalence using data from the 2008-2011 Korea National Health and Nutrition Examination Survey (KNHANES), which was a cross-sectional survey of 8,947 children up to age 18 throughout the country. Overall, 13.50% of children reported a diagnosis of AD. The age-standardized prevalence ranged from 9.13% to 17.67% between cities and provinces, with the highest prevalence-observed in many of the larger cities at low latitudes, as well as Jeju-do. After adjusting for confounders, high economic status was found to be a significant factor for predicting increased prevalence of AD, with an odds ratio of 1.35 (95% confidence interval of 1.02-1.79, P=0.0034). Urban living (odds ratio 1.24, 95% confidence interval of 1.00-1.53, P=0.0526) was also associated with a higher prevalence of AD. In this first large scale, nationwide study in Korean children, we found that the overall prevalence of AD depends on age, household income, and geographic distribution.

Mold allergens in respiratory allergy: from structure to therapy

Allergic reactions to fungi were described 300 years ago, but the importance of allergy to fungi has been underestimated for a long time. Allergens from fungi mainly cause respiratory and skin symptoms in sensitized patients. In this review, we will focus on fungi and fungal allergens involved in respiratory forms of allergy, such as allergic rhinitis and asthma. Fungi can act as indoor and outdoor respiratory allergen sources, and depending on climate conditions, the rates of sensitization in individuals attending allergy clinics range from 5% to 20%. Due to the poor quality of natural fungal allergen extracts, diagnosis of fungal allergy is hampered, and allergen-specific immunotherapy is rarely given. Several factors are responsible for the poor quality of natural fungal extracts, among which the influence of culture conditions on allergen contents. However, molecular cloning techniques have allowed us to isolate DNAs coding for fungal allergens and to produce a continuously growing panel of recombinant allergens for the diagnosis of fungal allergy. Moreover, technologies are now available for the preparation of recombinant and synthetic fungal allergen derivatives which can be used to develop safe vaccines for the treatment of fungal allergy.