Related Allergens Research Articles

Modern problems of sensitization to panallergens

Pan-allergens are molecules, mainly proteins of various families, responsible for cross–reactivity to a wide range of related and unrelated allergens. The clinical significance of having sensitization to some pan-allergens, for example, nsLTP, parvalbumins, storage proteins grows from the fact that severe, generalized reactions can develop, for example, nsLTP syndrome. Sensitization to pan-allergens depends on many factors, such as geographical location, age, food preferences, socioeconomic characteristics of the patient. The aim of the study is to identify the pattern of the sensitization to various molecules of pan-allergens in patients with allergic diseases living in the central part of Russia. We analyzed the sera of a total of 556 patients with allergic diseases in a multiplex enzyme immunoassay. Six profilin molecules, 2 polcalcin molecules, 12 – nsLTP, and 7 parvalbumin molecules were used. The frequency of IgE-ab to profilins in patients in central Russia is low (5-7%). At the same time, almost all patients with IgE-ab to profilins have IgE-ab to Bet v 1 (PR-10) and concomitantly to other profilins. In this regard, Bet v 1 can be considered as a primary sensitizer. The peculiarity of sensitization to polcalcins and LTPs was the low frequency of detection of IgE-ab to them (from 0.2% to 3%). At the same time, neither the nsLTP molecules of a peach, nor even apples, which are often consumed in central Russia, provoke the development of nsLTP syndrome. The detection rate of IgE-ab to parvalbumin in the sera of all patients with allergic reactions is also relatively not high and is 7-10%. Whereas the frequency of detection of IgE-ab to parvalbumins in the sera of patients with fish allergy is very high and reaches 63-90%. As a rule, IgE-ab are detected to all molecules, i.e., for parvalbumins of all studied fish species. The sensitization profile to profilins, polcalcins, nsLTP and parvalbumins in patients living in central Russia has its own unique characteristics. One of the primary sensitizers in patients with sensitization to pollen of wind-pollinated trees is Bet v 1 (PR-10 homologue), IgE-ab to which was detected in 42% of patients. The detection rate of IgE-ab for various molecules of pan-allergens in general was low as follows: profilins – 5-7%, polcalcins – 0.5%, nsLTP – 0.2-3%, and parvalbumins – 7-10%.

Cross‐protection of AIT‐induced antibodies to related allergens requires a high degree of structural identity

AbstractBackgroundIn contrast to sublingual immunotherapy (SLIT) with recombinant Mal d 1 (rMal d 1‐SLIT), SLIT with rBet v 1 (rBet v 1‐SLIT) induced Mal d 1‐cross‐reactive antibodies without IgE‐blocking activity. To elucidate whether the development of cross‐protective IgG responses depends on the degree of molecular identity of allergens we compared the cross‐reactivity, cross‐blocking activity, and affinity of SLIT‐induced antibodies with allergens of varying amino acid sequence identities to Bet v 1 and Mal d 1, namely Cor a 1.04 (hazelnut), Pru av 1 (cherry), and Dau c 1 (carrot).MethodsAllergen‐specific antibodies were quantified by ELISA. IgE blocking was analyzed by inhibition of allergen‐induced basophil activation and IgE‐facilitated allergen‐presentation to T cells. The affinity of SLIT‐induced antibodies was studied by acidic dissociation ELISA and competition ELISA. Identical surface areas on allergens were predicted using an in‐house designed script based on structural alignments.ResultsrBet v 1‐SLIT‐induced IgG antibodies cross‐reacted with all allergens except Dau c 1. rMal d 1‐SLIT‐induced antibodies predominantly cross‐reacted with Pru av 1 and displayed significantly higher IgE blocking to Pru av 1 than rBet v 1‐SLIT‐induced antibodies. rMal d 1‐SLIT‐induced IgG1 showed higher affinity to Mal d 1 and Pru av 1. Surface analysis revealed 84% identical area on Mal d 1 and Pru av 1. Furthermore, we identified two surface areas potentially containing epitopes present on these allergens and absent on Bet v 1.ConclusionIn summary, our findings suggest that a relatively high threshold of similarity is required to establish effective cross‐blocking antibodies to related allergens. Apparently, the structural identity between Bet v 1 and Mal d 1 is below this threshold. Therefore, this study may explain why immunotherapy with birch pollen allergen often fails to reduce birch pollen‐related apple allergy.

Poppy Seed Allergy: Molecular Diagnosis and Cross-Reactivity With Tree Nuts

BackgroundPoppy seed (PS) can be a cause of severe allergic reactions, especially in individuals with concurrent allergy to tree nuts and other seeds, but diagnostic criteria and sensitization patterns are lacking. ObjectiveTo assess the role of PS extract and individual allergens in diagnosing PS allergy and their cross-reactivities with tree nuts and buckwheat. MethodsOur retrospective study included 36 PS-sensitized patients; 10 with positive and 26 with a negative oral food challenge (OFC). We identified individual PS allergens and compared the diagnostic performance of sIgE to PS extract to its allergens. Cross-reactivities between PS and related allergens from other seeds was assessed by competitive ELISA. ResultsWe identified four novel PS allergens: Pap s 1 (vicilin), Pap s 1 (27-424) (α-hairpinin), Pap s 2 (legumin), and Pap s 3 (small hydrophilic seed protein). Positive OFC correlated with higher PS-sIgE levels and elevated sIgE levels for the PS allergens, except for Pap s 3. PS and α-hairpinin-sIgE effectively differentiated allergic from tolerant patients, with AUC values of 0.95 and 0.94. PS-sIgE >10.00 kUA/L exhibited 90% sensitivity and 73% specificity, while α-hairpinin -sIgE >2.60 kUA/L showed 100% sensitivity and 77% specificity. PS vicilin and legumin highly cross-reacted with hazelnut and buckwheat homologues, while α-hairpinin-sIgE cross-reacted with the related almond allergen. ConclusionsThis is the most extensive study on poppy seed allergy to date. Poppy seed and α-hairpinin-sIgE are highly sensitive indicators of clinical reactivity to poppy seeds, while vicilin and legumin-sIgE contribute to concurrent sensitization to hazelnut and buckwheat.

Trimeric Bet v 1-specific nanobodies cause strong suppression of IgE binding.

Around 20% of the population in Northern and Central Europe is affected by birch pollen allergy, with the major birch pollen allergen Bet v 1 as the main elicitor of allergic reactions. Together with its cross-reactive allergens from related trees and foods, Bet v 1 causes an impaired quality of life. Hence, new treatment strategies were elaborated, demonstrating the effectiveness of blocking IgG antibodies on Bet v 1-induced IgE-mediated reactions. A recent study provided evidence for the first time that Bet v 1-specific nanobodies reduce patients´ IgE binding to Bet v 1. In order to increase the potential to outcompete IgE recognition of Bet v 1 and to foster cross-reactivity and cross-protection, we developed Bet v 1-specific nanobody trimers and evaluated their capacity to suppress polyclonal IgE binding to corresponding allergens and allergen-induced basophil degranulation. Nanobody trimers were engineered by adding isoleucine zippers, thus enabling trimeric formation. Trimers were analyzed for their cross-reactivity, binding kinetics to Bet v 1, and related allergens, and patients' IgE inhibition potential. Finally, their efficacy to prevent basophil degranulation was investigated. Trimers showed enhanced recognition of cross-reactive allergens and increased efficiency to reduce IgE-allergen binding compared to nanobody monomers. Furthermore, trimers displayed slow dissociation rates from allergens and suppressed allergen-induced mediator release. We generated high-affine nanobody trimers that target Bet v 1 and related allergens. Trimers blocked IgE-allergen interaction by competing with IgE forallergen binding. They inhibited IgE-mediated release of biological mediators, demonstrating a promising potential to prevent allergic reactions caused by Bet v 1 and relatives.

Immunobiological properties and structure analysis of group 13 allergen from Blomia tropicalis and its IgE-mediated cross-reactivity

Blomia tropicalis is an important species of allergenic mite. Structurally related cross-reactive allergens are involved in pathogenesis of clinical symptoms. The present study focused on recombinant allergen rBlo t 13 from B. tropicalis, including investigation of its structure, immunological properties, IgE-mediated cross-reactivity. In this work, the prokaryotic expression plasmids pET-28(a)-Blo t 13, pET-28(a)-Der f 13, and pET-28(a)-Tyr p 13 were constructed, transformed into E. coli Rosetta (DE3) pLysS, and purified by nickel affinity chromatography, respectively. By using ELISA, the IgE-binding rates were detected for rBlo t 13 and its epitope peptides, as well as the cross-reactivity among rBlo t 13, rDer f 13, and rTyr p 13. The tertiary structure of rBlo t 13 was resolved using X-ray diffraction at 2.0 Å resolution. Using IgE-ELISA, the IgE binding rate of rBlo t 13 was 60 % with Blomia tropicalis-positive sera. In the experiments of ELISA for cross-reactivity with rBlo t 13 on solid phase, the inhibition rates were 65 %, 57 % and 63 % for rBlo t 13, rDer f 13, and rTyr p 13, respectively. The structure of Blo t 13 protein contains a β-barrel structure which is composed of 10 β strands and has 2 α helices at the end of the barrel. Comparison of the tertiary structures of rBlo t 13, rDer f 13, and rTyr p 13 revealed that the β-barrel structure is highly conserved, consistent with the alignment of amino acid sequences. We obtained the recombinant protein rBlo t 13, demonstrated its cross-reactivity with Der f 13 and Tyr p 13 due to their structural similarity.

Nickel hypersensitivity, Contact dermatitis, Biosensor, Patch test

Usage of numerous dental materials, starting from diagnosis to rehabilitation for the management of oral diseases are not devoid of posing a potential risk of inducing allergic reactions to the patient, technician and dentist. The materials used for dental restorations, orthodontic instruments etc must satisfy the biocompatibility specifications since they are indicated for a long time in the oral cavity. Popular usage of nickel in dentistry has brought about an unpopular trend in allergic reactions. The wave of metal allergies that are the result of nickel usage in orthodontics, are more prevalent in dentistry Metallic taste, angular cheilitis, and periodontitis may be associated with release of nickel from orthodontic appliances. It is manifested as Nickel Allergic Contact Stomatitis (NiACS). A burning sensation is the most frequent symptom A systematic approach for the selection and monitoring of dental materials used in orthodontics thereby giving an insight to predict their risk of inducing allergic reactions. The scope of detection of dental materials related allergies can be used chairside before introducing the material to the oral cavity. Use of detection may not be used only for diagnostic method but also a therapeutic method. Hence, dental materials related allergen detection, and management have become significant priorities within the healthcare fraternity, and there is an urgent requirement for reliable, sensitive, and user-friendly technologies to trace allergens in dental materials.

Effects of Interventions to Prevent Work-Related Asthma, Allergy, and Other Hypersensitivity Reactions in Norwegian Salmon Industry Workers (SHInE): Protocol for a Pragmatic Allocated Intervention Trial and Related Substudies.

Workers in the salmon processing industry have an increased risk of developing respiratory diseases and other hypersensitivity responses due to occupational exposure to bioaerosols containing fish proteins and microorganisms, and related allergens. Little is known about effective measures to reduce bioaerosol exposure and about the extent of skin complaints among workers. In addition, while identification of risk factors is a core activity in disease prevention strategies, there is increasing interest in health-promoting factors, which is an understudied area in the salmon processing industry. The overall aim of this ongoing study is to generate knowledge that can be used in tailored prevention of development or chronification of respiratory diseases, skin reactions, protein contact dermatitis, and allergy among salmon processing workers. The main objective is to identify effective methods to reduce bioaerosol exposure. Further objectives are to identify and characterize clinically relevant exposure agents, identify determinants of exposure, measure prevalence of work-related symptoms and disease, and identify health-promoting factors of the psychosocial work environment. Data are collected during field studies in 9 salmon processing plants along the Norwegian coastline. Data collection comprises exposure measurements, health examinations, and questionnaires. A wide range of laboratory analyses will be used for further analysis and characterization of exposure agents. Suitable statistical analysis will be applied to the various outcomes of this comprehensive study. Data collection started in September 2021 and was anticipated to be completed by March 2023, but was delayed due to the COVID-19 pandemic. Baseline data from all 9 plants included 673 participants for the health examinations and a total of 869 personal exposure measurements. A total of 740 workers answered the study's main questionnaire on demographics, job characteristics, lifestyle, health, and health-promoting factors. Follow-up data collection is not completed yet. This study will contribute to filling knowledge gaps concerning salmon workers' work environment. This includes effective workplace measures for bioaerosol exposure reduction, increased knowledge on hypersensitivity, allergy, respiratory and dermal health, as well as health-promoting workplace factors. Together this will give a basis for improving the work environment, preventing occupational health-related diseases, and developing occupational exposure limits, which in turn will benefit employees, employers, occupational health services, researchers, clinicians, decision makers, and other stakeholders. ClinicalTrials.gov NCT05039229; https://www.clinicaltrials.gov/study/NCT05039229. DERR1-10.2196/48790.

Structural and ligand binding analysis of the pet allergens Can f 1 and Fel d 7.

Pet lipocalins are respiratory allergens with a central hydrophobic ligand-binding cavity called a calyx. Molecules carried in the calyx by allergens are suggested to influence allergenicity, but little is known about the native ligands. To provide more information on prospective ligands, we report crystal structures, NMR, molecular dynamics, and florescence studies of a dog lipocalin allergen Can f 1 and its closely related (and cross-reactive) cat allergen Fel d 7. Structural comparisons with reported lipocalins revealed that Can f 1 and Fel d 7 calyxes are open and positively charged while other dog lipocalin allergens are closed and negatively charged. We screened fatty acids as surrogate ligands, and found that Can f 1 and Fel d 7 bind multiple ligands with preferences for palmitic acid (16:0) among saturated fatty acids and oleic acid (18:1 cis-9) among unsaturated ones. NMR analysis of methyl probes reveals that conformational changes occur upon binding of pinolenic acid inside the calyx. Molecular dynamics simulation shows that the carboxylic group of fatty acids shuttles between two positively charged amino acids inside the Can f 1 and Fel d 7 calyx. Consistent with simulations, the stoichiometry of oleic acid-binding is 2:1 (fatty acid: protein) for Can f 1 and Fel d 7. The results provide valuable insights into the determinants of selectivity and candidate ligands for pet lipocalin allergens Can f 1 and Fel d 7.

Decreased IgE Binding and Less Allergenic Protein Per Unit Mass in Bamba Peanut Snack Compared to Crushed Peanut

Substrates for peanut oral immunotherapy (OIT) vary, including crushed peanut and Bamba peanut snack (Osem, Israel). While the total peanut protein content in each food has been estimated, specific IgE binding levels, protein extractability, and relative allergen content have not been compared.

Association between early life exposure to indoor environmental factors and childhood asthma

BackgroundAsthma is one of the most common chronic diseases among childhood worldwide, with a rapid increase in developing countries over past decades. Although increasing evidence have linked asthma with indoor environments, their role in early life on asthma development is unclear. ObjectiveWe aim to investigate the association between childhood doctor-diagnosed asthma (DDA) and indoor environmental exposure in four important time windows across lifetime. MethodsWe conducted a retrospective cohort study with 8689 children in Changsha, China during 2019–2020. Every child's health condition and home environments were collected by our questionnaire. The time windows of indoor air pollution (IAP) and allergens at home included 1 year before pregnancy, pregnancy, the 1st year after birth, and 1 year before filling in the questionnaire. We used multiple logistic regression models to analyse the associations. ResultsWe found that exposure to indoor dampness related allergen including mold/damp stains and mold/damp clothes or bedding during four windows were significantly associated with an increased risk of childhood DDA. Childhood DDA was also related with smoke related IAP in pregnancy, 1st year, and past year and renovation related IAP including new furniture and redecoration in pregnancy with ORs (95% CI) = 1.53 (1.12–2.09) and 1.47 (1.02–2.12) after adjusting for covariates and outdoor air pollution and temperature. Pregnancy was identified as the critical time window in home environmental exposure for asthma development, especially for exposure to environmental tobacco smoke (ETS), new furniture, and mold/damp clothes and bedding, with ORs (95% CI) = 1.39 (1.00–1.93), 1.50 (1.09, 2.06), and 1.55 (1.01–2.38). Some specific subjects were more sensitive to the effect of home environments on asthma. ConclusionThis study indicates that exposure to indoor air pollution and allergens in early life plays an important role in the development of childhood asthma, supporting a hypothesis of “(pre-)fetal origin of childhood asthma”.

Effects of early life exposure to home environmental factors on childhood allergic rhinitis: Modifications by outdoor air pollution and temperature.

There is growing evidence that allergic rhinitis (AR) is associated with indoor environmental factors, but their role in childhood AR during early life remains unclear. To investigate the association of preconceptional, prenatal, early postnatal, and current exposure to home environmental factors with childhood AR, and to further explore whether this association can be interacted by outdoor air pollution and temperature. A retrospective cohort study of 8689 preschool children was conducted during 2019-2020 in Changsha, China. A standard questionnaire was used to collect data on each family's health outcomes and home environments. We considered home environmental exposures during one year before conception, pregnancy, first year of life, and past year. Associations of indoor air pollution and allergens with AR were assessed by multiple logistic regression models. Pre-birth exposure to indoor air pollution emitted by new furniture or redecoration and dampness related allergen derived from mold/damp stains and mold/damp clothes or bedding during 1 year before conception and pregnancy was significantly associated with increased AR, with adjusted ORs (95% CI) ranging from 1.35 (1.05-1.75) to 1.87 (1.55-2.27). Childhood AR was also significantly related with post-birth exposure to dampness related indoor allergen including mold/damp stains and mold/damp clothes or bedding in first year and past year and pollen allergen including total and nonflowing plants in past year, with a range of ORs (95% CI) from 1.20 (1.01-1.42) to 1.79 (1.42-2.27). We identified that pre-birth, particularly in utero exposure to both indoor air pollution from renovation and dampness related allergens, played a key role in AR development compared to post-birth exposures, and accumulative effect was observed with the highest risk of AR. High exposure to traffic-related air pollution (TRAP) including outdoor PM2.5, NO2, CO, and O3, as well as living near traffic road not only significantly increased adverse effect of home environmental factors but also decreased protective effect of household dogs on childhood AR. Early life exposure to low temperature in pregnancy and high temperature in first year significantly increased AR risk of home environmental exposure. Sensitivity analysis indicated that some sub-groups were more susceptible to AR risk of home environmental exposure. Our study suggests that pre-birth exposure to home environmental factors played an important role in AR development and this effect can be interacted by TRAP and temperature, which supports a hypothesis of "(pre)fetal origin of childhood AR".

A comprehensive analysis of the components of common weed pollen and related allergens in patients with allergic diseases in southern China

BackgroundPollen allergens are vital contributors to allergic diseases. The frequency and coreactivity pattern of allergens are closely related to geographical distribution. ObjectiveIn this study, we aimed to characterize the prevalence of the molecular components of the common weed pollen allergens, birch pollen, walnut, and cross-reactive carbohydrate determinant (CCD), as well as investigate the relationship between the allergens and CCD in Chinese pollen-sensitized patients with allergic diseases. MethodsBased on previous vegetation surveys, serum samples from 165 pollen-sensitized patients with allergic diseases in Guangdong Province in southern China were used to test 19 crude allergen extracts, their components, and CCD using component-resolved diagnosis (CRD). Moreover, the potential associations among CCD, allergens, and their components were described. ResultsIn the 165 samples, the most common sensitized allergens were goosefoot (43.0%), ragweed (40.6%), walnut (37.6%), walnut tree (37.6%), and mugwort (37.0%), followed by platane (35.2%), cocklebur (27.9%), and birch (24.2%). The positivity rate of CCD was 39.4%. Among the samples positive for mugwort, 11 (18.0%), 15 (24.6%), and 15 (24.6%) were positive for Art v 1, Art v 2, and Art v 3, respectively. Among the 67 patients sensitized to ragweed, only five (7.5%) were positive for Amb a 1. In the 40 patients sensitized to birch, Bet v 2 had the highest positivity rate (40.0%). There were 62 patients who were sensitized to walnut. Their components had a lower positivity rate (less than 15%). The hierarchical clustering and optimal scale analysis showed that Art v 4 and Bet v 2 were closely related, and 91.9% of CCD-positive samples were polysensitized. Meanwhile, Spearman's rank correlation method showed that CCD was closely correlated with the sensitization of crude allergen extracts, and there was a low correlation between CCD and allergen components. CCD was highly correlated with goosefoot, ragweed, and walnut trees (r＞0.8). Moreover, there was a strong relationship between the levels of Jug r 3 and Art v 3 (r = 0.78; P < 0.001). ConclusionsIn southern China, the weed pollens (ragweed, cocklebur, and goosefoot) exhibited higher positivity rates in adults and had a stronger relationship with CCD but not with mugwort. The positivity rate of allergen components was not high. CCD-positive samples were always polysensitized.

Peculiarities of the etiological spectrum of household allergens

The aim of the study was to study the range of substances that cause respiratory sensitization in adults and children living in Dnipro as of 2019.&#x0D; Materials and research methods. Enzyme-linked immunosorbent assay was used to study the serum of venous blood, which determined the specific IgE of up to 9 allergens that are most common in the home. Kits for quantification of allergen-specific IgE from Vitrotest Specific-IgE, Ukraine were used. Conducted allergy diagnosis for 380 people with certain features of allergy history of various types of allergies, who went to the laboratory to specify the etiological root cause of their disease.&#x0D; Research results. As a result of the analysis of the received data the distribution of allergens on their prevalence among the population of Dnipro was established. The degree of hypersensitivity to each specific allergen and their ability to cross-react with each other was determined. Among the allergens of the household panel, the most dangerous were allergens of molds, which caused a sensitization reaction in 292 people, which was 76.8 % of all surveyed. The top three (in prevalence) of household allergens included: cat epithelium, which caused sensitization in 125 people (32.9 %) and Derm mite. Farinae, sensitivity to which was found in 117 patients (30.7 %). The share of inadequately strong allergopathological reactions is one third of all examined and prevails in people with sensitization to allergic agents of the household panel such as cat epithelium, Derm mite. Farinae and Derm. Pteronyssinus. Hyperractivity to fungi of the genus Candida and mold has been found in 9–12 % of people. The lowest severity of sensitization was observed in the epithelium of the dog and house dust, and low sensitivity in the reactivity structure of allergopathological reactions was observed for allergens of the epidermal group (down and feathers of poultry) and cockroaches. The development of cross-reactions took place between allergens of epidermal origin: there was a hypersensitivity to the hair and epithelium of dogs and cats (r=0.94, P˂0.01), poultry feathers and cockroaches (r=0.99, P˂0.01). This association of cross-reactions is possible, given the theory of minor and major proteins, and is due to their similarity: the similarity of the inclusion in the allergen structures of specific forms of molecules inherent in both allergic agents that may have allergy-stimulating effects.&#x0D; Conclusions. Cross-linking between several types of related allergens is the best way to further investigate this issue. It makes sense to include in the laboratory study a molecular method for the determination of major and minor proteins in the case of the greatest relationship to determine not only a specific allergen as an etiological factor, but also a specific sensitizing protein that is part of them. This is of great importance for subsequent immunotherapy when the removal of only one (major) protein agent can reduce the risk of susceptibility reactions to several types of allergens

Allergen Immunotherapy: Current and Future Trends.

Allergen immunotherapy (AIT) is the sole disease-modifying treatment for allergic rhinitis; it prevents rhinitis from progressing to asthma and lowers medication use. AIT against mites, insect venom, and certain kinds of pollen is effective. The mechanism of action of AIT is based on inducing immunological tolerance characterized by increased IL-10, TGF-β, and IgG4 levels and Treg cell counts. However, AIT requires prolonged schemes of administration and is sometimes associated with adverse reactions. Over the last decade, novel forms of AIT have been developed, focused on better allergen identification, structural modifications to preserve epitopes for B or T cells, post-traductional alteration through chemical processes, and the addition of adjuvants. These modified allergens induce clinical-immunological effects similar to those mentioned above, increasing the tolerance to other related allergens but with fewer side effects. Clinical studies have shown that molecular AIT is efficient in treating grass and birch allergies. This article reviews the possibility of a new AIT to improve the treatment of allergic illness.

Occupational Contact Dermatitis in Dental Personnel: A Retrospective Analysis of the North American Contact Dermatitis Group Data, 2001 to 2018.

Dental personnel are at risk of developing occupational contact dermatitis. The aims of the study were to determine prevalence of occupational contact dermatitis in dental personnel referred for patch testing and to characterize relevant allergens and sources. The study used a retrospective, cross-sectional analysis of the North American Contact Dermatitis Group (NACDG) data, 2001-2018. Of 41,109 patients, 585 (1.4%) were dental personnel. Dental personnel were significantly more likely than nondental personnel to be female (75.7% vs 67.4%, P < 0.0001), have occupationally related dermatitis (35.7% vs 11.5%, P < 0.0001), and/or have primary hand involvement (48.6% vs 22.5%, P < 0.0001). More than one quarter of dental personnel (62/585, 27.7%) had 1 or more occupationally related allergic patch test reaction(s). There were 249 occupationally related reactions to NACDG screening allergens, most commonly glutaraldehyde (18.1%), thiuram mix (16.1%), and carba mix (14.1%). The most common sources of NACDG screening allergens were gloves (30.7%), dental materials (26.6%), and sterilizing solutions (13.1%). Seventy-three dental personnel (12.5%) had 1 or more positive patch test reactions to occupationally related allergen(s)/substances not on the screening series. Occupationally related irritant contact dermatitis was identified in 22.2% (n = 130) of dental personnel, most commonly to nonskin soaps/detergents/disinfectants (32.0%). Occupational contact dermatitis is common in dental personnel referred for patch testing. Comprehensive testing beyond screening series is important in these patients.

Systemic manifestations and treatment algorithm of food allergy

Food allergy or hypersensitivity can be defined as the presence of an observable immune secondary reaction to the administration of certain proteins that are present within the ingested foods. It has been previously estimated that around 2-10% of the general population suffer from IgE-mediated food allergy. Furthermore, identification of the manifestations is a key point to achieve appropriate evaluation and management of this condition. In this literature review, we aim to discuss the systemic manifestations and treatment algorithm for patients who suffer from a food allergy, according to the current evidence from studies in the literature. Gastrointestinal and skin-related manifestations have been reported to be the most common symptom. However, respiratory tract symptoms are also common and might severely deteriorate the affected patients. The development of severe anaphylaxis is also life-threatening with multiple organ affection. The appropriate management of food hypersensitivity is mainly based on the proper intervention from exposure to the related allergens. In addition, another appropriate management is early sensitization during the first few months of infancy to manage the symptoms of affected patients. Additionally, it should also be noted that most children usually develop tolerance, and the reported allergy to certain types of foods during childhood usually fades away by the age from 8 to12 years old and also during the period of adolescence. Future studies are needed to develop adequate management modalities with favorable safety and efficacy outcomes.

Contact Dermatitis Associated With Hair Care Products: A Retrospective Analysis of the North American Contact Dermatitis Group Data, 2001-2016.

Hair care products (HCPs) may cause both allergic contact dermatitis (ACD) and irritant contact dermatitis (ICD). The aims of the study were to determine the prevalence of HCP-associated ICD/ACD and to characterize relevant allergens. This study is a retrospective analysis of North American Contact Dermatitis Group (NACDG) patch test data, 2001-2016. Of 38,775 patients tested, 3481 (9.0%) had positive patch test reactions associated with HCPs. The HCP-positive patients were significantly more likely to be female (79.9% vs 66.0%) and/or have primary sites of dermatitis on the face (32.0% vs 27.8%) or scalp (15.4% vs 2.2%) compared with the HCP-negative patients (P < 0.0001). Of 4908 HCP-associated positive patch test reactions, 86.9% (n = 4263) were due to allergens on the NACDG screening series; p-phenylenediamine (35.8%), methylisothiazolinone (9.7%), methylchloroisothiazolinone/methylisothiazolinone (8.7%), and cocamidopropyl betaine (5.9%) were the most frequent. Most reactions (87.7%, 3736/4263) were currently clinically relevant. The most common job associated with 366 occupationally related NACDG HCP-associated allergens was hairdresser/cosmetologist (71.9%). Two hundred eighty-two patients (0.7%) had ICD associated with HCPs. Shampoo/conditioners were the most frequent source of NACDG HCP-associated reactions (47.3%) and HCP-associated ICD (45.0%). Of the HCP-positive patients, 18.5% had HCP reactions to allergens not on the NACDG screening series, underscoring the importance of patch testing to expanded series in patients suspected of HCP allergy.

Occupational contact dermatitis: Retrospective analysis of North American Contact Dermatitis Group Data, 2001 to 2016

Patch testing is an important diagnostic tool for suspected allergic contact dermatitis (ACD) in occupational settings. Provide an overview of occupational skin disease (OSD) and an analysis of occupational ACD in North American patients undergoing patch testing between 2001and 2016. Patients with OSD were analyzed for frequency of allergic reactions to a screening series of allergens, occupational relevance, location of skin disease, and exposure sources. Demographic, occupation, and industry information were recorded. Of 38,614 patients evaluated, 4471 (11.6%) had OSD, of whom 3150 (70.5%) had ACD. The most common occupationally related allergens included rubber accelerators, preservatives, and bisphenol A epoxy resin. Hands (75.8%), arms (30.0%), and face (15.9%) were common sites of dermatitis. The occupations most affected were service workers and machine operators. Our cohort may not reflect the general working population. This study identified common occupational allergens, exposure sources, and occupations/industries at risk. This information may help the clinician evaluate and manage patients with occupational contact dermatitis.

Food antigen-specific IgE in dogs with suspected food hypersensitivity

Knowledge of cross-reactions in food-sensitive dogs will influence the choice of elimination diets and the long-term management of those patients. The objective of this study was to evaluate food allergen-specific IgE tests of suspected allergic dogs for concurrent positive reactions as possible evidence for cross reactions between allergens. Results of serum IgE tests from 760 suspected allergic dogs submitted to 2 laboratories were evaluated statistically. After the tested allergens were grouped by their phylogenetic relationship, odds ratios as well as a sensitivity analysis of the odds ratios were performed to evaluate if concurrent positive IgE results to 2 allergens occurred more often than expected. Within related allergen pairs 27% (laboratory 1) and 72% (laboratory 2) of the pairs could be considered as associated. For the unrelated allergen pairs only 6.8% and 10.6% of the analyzed pairs were considered associated respectively. Strong correlations were shown in the group of ruminant allergens, especially beef and lamb, and grain allergens. High rates of concurrent reactions were also detected in the poultry group, especially between chicken and duck, as well as between pork and ruminant allergens, and soy and grain allergens. As our results showed not only correlations within related but also between non-related allergens, the possible relevance of carbohydrate moieties as well as panallergens for canine hypersensitivities warrants further study. Further investigations are necessary to distinguish co-sensitization from cross-reactions and determine the clinical relevance of food-specific IgE reactivity. Due to possible cross reactivity related allergens, especially beef and lamb as well as grain allergens, should not be used for an elimination diet to avoid false results.

Correlation of skin prick testing to environmental allergens

BackgroundTo diagnose and adequately treat allergies, identification of sensitizing allergens is crucial. Skin prick or serum immunoglobulin E testing determines sensitization to potential allergens. Consensus varies regarding degree of cross-reactivity between aeroallergens. ObjectiveTo quantify correlations between aeroallergen skin prick test results. MethodsA total of 11,832 patients’ quantitative skin prick test results and basic characteristics were obtained from a tertiary academic center’s electronic medical record and deidentified. Data were analyzed using Spearman’s rank correlation coefficients to detect nonlinear associations between wheal sizes of skin prick test results. ResultsThe highest correlation among grasses was 0.903 (fescue and red top). Of note, 13 more grass pairs had correlation more than 0.8, and 19 had correlation between 0.7 and 0.8. The Northern grass comparative results are from a satellite clinic that tested more grasses than the main clinic, in which only Kentucky blue and Bermuda were tested (correlation 0.768; n = 9348). Highest correlation among weeds was 0.74 (lambs quarter and pigweed). In addition, 6 more weed pairs had correlation more than 0.7. Highest correlation among trees was 0.724 (palm and alder) and 6 more tree pairs had correlation more than 0.7. Highest correlation among molds was 0.711 (Helminthosporium and Epicoccum). Dust mite correlation between Dermatophagoides farinae and Dermatophagoides pteronyssinus was 0.848 (n = 10,022). ConclusionThis study confirmed the expected high degrees of correlation not only between skin prick test results of related environmental allergens but also between less closely related Northern grasses and Bermuda grass. This has implications for simplification of testing and immunotherapy protocols in the future.