Skin testing for inhalant allergy

International consensus statement on allergy and rhinology: Allergic rhinitis - 2023

BACKGROUND

In the 5 years that have passed since the publication of the 2018 International Consensus Statement on Allergy and Rhinology: Allergic Rhinitis (ICAR-Allergic Rhinitis 2018), the literature has expanded substantially. The ICAR-Allergic Rhinitis 2023 update presents 144 individual topics on allergic rhinitis (AR), expanded by over 40 topics from the 2018 document. Originally presented topics from 2018 have also been reviewed and updated. The executive summary highlights key evidence-based findings and recommendation from the full document.

METHODS

ICAR-Allergic Rhinitis 2023 employed established evidence-based review with recommendation (EBRR) methodology to individually evaluate each topic. Stepwise iterative peer review and consensus was performed for each topic. The final document was then collated and includes the results of this work.

RESULTS

ICAR-Allergic Rhinitis 2023 includes 10 major content areas and 144 individual topics related to AR. For a substantial proportion of topics included, an aggregate grade of evidence is presented, which is determined by collating the levels of evidence for each available study identified in the literature. For topics in which a diagnostic or therapeutic intervention is considered, a recommendation summary is presented, which considers the aggregate grade of evidence, benefit, harm, and cost.

CONCLUSION

The ICAR-Allergic Rhinitis 2023 update provides a comprehensive evaluation of AR and the currently available evidence. It is this evidence that contributes to our current knowledge base and recommendations for patient evaluation and treatment.

Comprehensive Analysis of the Structure and Allergenicity Changes of Seafood Allergens Induced by Non-Thermal Processing: A Review

Seafood allergy, mainly induced by fish, shrimp, crab, and shellfish, is a food safety problem worldwide. The non-thermal processing technology provides a new method in reducing seafood allergenicity. Based on the structural and antigenic properties of allergenic proteins, this review introduces current methods for a comprehensive analysis of the allergenicity changes of seafood allergens induced by non-thermal processing. The IgE-binding capacities/immunoreactivity of seafood allergens are reduced by the loss of conformation during non-thermal processing. Concretely, the destruction of native structure includes degradation, aggregation, uncoiling, unfolding, folding, and exposure, leading to masking of the epitopes. Moreover, most studies rely on IgE-mediated assays to evaluate the allergenic potential of seafood protein. This is not convincing enough to assess the effect of novel food processing techniques. Thus, further studies must be conducted with functional assays, in vivo assays, animal trials, simulated digestion, and intestinal microflora to strengthen the evidence. It also enables us to better identify the effects of non-thermal processing treatment, which would help further analyze its mechanism.

Clinical characteristics of asymptomatic allergen sensitization with nasal septal deviation, often misdiagnosed as allergic rhinitis

PURPOSE

Allergic rhinitis (AR) is often defined based on symptoms accompanied by a positive allergen sensitivity test result. However, a positive skin prick test (SPT) does not always imply the occurrence of clinical symptoms. If an asymptomatic allergen-sensitized patient has nasal septal deviation (DSN) that could cause nasal obstruction, the condition could easily be confused with typical symptomatic AR. This study investigated the clinical and laboratory characteristics of asymptomatic allergen-sensitization with septal deviation (ASSD).

METHODS

Patients from a nationwide AR cohort study, conducted in 8 university hospitals, were investigated. AR was diagnosed when there were at least 1 rhinitis symptom with a positive SPT result. The ASSD group included patients who had severe nasal obstruction with few other symptoms and a positive SPT, along with septal deviation. Clinical and laboratory characteristics were compared between the ASSD group and the true AR group.

RESULTS

In total, 728 patients were included. The average age was 32.2 ± 12.7 and 66% of the patients had DSN. SPT indicated that ASSD patients were less sensitized to house dust mite (p = 0.019 for Dp and p = 0.021 for Df). There was a significant sex difference: the male-to-female ratio was higher in the ASSD than in the AR group (3.59 vs. 1.77, p = 0.012). However, no statistically significant differences in age, family history, and body mass index were found.

CONCLUSION

ASSD can mimic AR. When dealing with allergen-sensitized patients with a predominant symptom of nasal obstruction, DSN might also be considered before confirming a diagnosis of AR.

Predictors of Completion of Sublingual Immunotherapy

OBJECTIVES

Sublingual immunotherapy (SLIT) has emerged as an effective treatment alternative to subcutaneous immunotherapy (SCIT) given its improved safety profile and more convenient dosing. However, SLIT still relies on daily dosing for many years to optimize effectiveness. This study sought to investigate factors that influence patient completion of SLIT.

METHODS

We performed an institutional retrospective review of patients who received SLIT (2008-2020). Completion was defined as completing at least 36 months of SLIT. Patient demographics and characteristics, including the number of allergens treated, history of asthma and sinus surgery, number of clinic visits, and total time undergoing SLIT, were documented. Multivariate models were used to analyze predictors of SLIT completion. Subgroup analysis was performed among pediatric patients and patients who discontinued SLIT.

RESULTS

Of the 404 total patients, 249 (61.6%) discontinued, 47 (11.6%) completed, and 108 (26.7%) were currently undergoing SLIT. The mean duration of therapy was 11.2 months for those who discontinued and 49.4 months for patients who completed SLIT. The odds of SLIT completion were twice as high with each additional clinic visit (P < .001), and twice as high when the dosage was increased during therapy (P = .06). Pediatric patients younger than age 12 with a history of asthma were over five times more likely to complete therapy (P = .045). Patients with more clinic visits (P < .001) and higher associated costs (P = .003) were less likely to be lost to follow-up.

CONCLUSION

Increasing the frequency of clinic visits, improving therapy availability, and mitigating concerns about clinical efficacy may increase patient completion of SLIT.

LEVEL OF EVIDENCE

4 Laryngoscope, 131:E2111-E2115, 2021.

Resolving Clinical Phenotypes into Endotypes in Allergy: Molecular and Omics Approaches

Allergic diseases are highly complex with respect to pathogenesis, inflammation, and response to treatment. Current efforts for allergic disease diagnosis have focused on clinical evidence as a binary outcome. Although outcome status based on clinical phenotypes (observable characteristics) is convenient and inexpensive to measure in large studies, it does not adequately provide insight into the complex molecular determinants of allergic disease. Individuals with similar clinical diagnoses do not necessarily have similar disease etiologies, natural histories, or responses to treatment. This heterogeneity contributes to the ineffective response to treatment leading to an annual estimated cost of $350 billion in the USA alone. There has been a recent focus to deconvolute the clinical heterogeneity of allergic diseases into specific endotypes using molecular and omics approaches. Endotypes are a means to classify patients based on the underlying pathophysiological mechanisms involving distinct functions or treatment response. The advent of high-throughput molecular omics, immunophenotyping, and bioinformatics methods including machine learning algorithms is facilitating the development of endotype-based diagnosis. As we move to the next decade, we should truly start treating clinical endotypes not clinical phenotype. This review highlights current efforts taking place to improve allergic disease endotyping via molecular omics profiling, immunophenotyping, and machine learning approaches in the context of precision diagnostics in allergic diseases. Graphical Abstract.

Evaluation of Interleukin-6, Leukotriene B-4, and Nitric Oxide Levels in Exhaled Breath Condensate of Asymptomatic Obese Individuals: Are Obese Patients Under Risk of Developing Asthma?

Objective

If systemic inflammation in relation with obesity causes asthma, the detection of increased airway inflammation among obese individuals who do not have any respiratory symptoms can be also beneficial in indentifying obese patients who are at risk of developing asthma. The aim of this study was to evaluate the systemic and airway inflammation of asymptomatic obese and non-obese individuals.

Materials and Methods

Obese and non-obese individuals with no respiratory symptoms were included. Inflammatory biomarkers such as C-reactive protein (CRP), exhaled breath condensate (EBC) interleukin-6 (IL-6), EBC leukotriene B-4 (LTB-4), and EBC nitric oxide (NO) levels of obese and non-obese individuals were determined.

Results

Forty-five obese individuals (body mass index [BMI]≥30) and 31 non-obese individuals (BMI≤25) as a control group were included in this study. The mean age of the obese group (38.7±11.4 years) was significantly higher than the one of the non-obese group (29.5±8.6 years; p<0.001). There was no significant relationship between gender and BMI (χ² =1.471, p=0.225). CRP levels were significantly higher in the obese group (6.94±8.28) than the non-obese group (3.29±0.39; p<0.001). The levels of EBC IL-6 in obese and non-obese group were found as 22.61±12.53 and 21.08±14.39, respectively (p=0.624). There was no significant difference between EBC NO levels of the obese group and non-obese group (24.35±10.9 vs. 21.56±7.83; p=0.226). No significant difference was found between the EBC LTB-4 level in the obese group and the non-obese group (36.39±89.82 vs. 16.64±17.45; p=0.231).

Conclusion

Increased systemic inflammation in obese individuals who had no respiratory symptoms might indicate the tendency of asthma. However, airway inflammation was not significantly different between groups. Therefore the relationship between obesity and asthma should be investigated in future large-scale studies determining the direct effects of adipokines on airways.

High volume of polysorbate-containing (Tween® 80) solutions induces false-positive results in intradermal test

BACKGROUND

Intradermal test is used to detect causative allergens in IgE-mediated hypersensitivity. The surfactant polysorbate 80 can be added to intradermal test solutions to more reliably dissolve the allergen and ensure a constant bioavailability of the injected allergen. Polysorbate 80 has, however, some histamine-releasing properties which could blur the difference to the histamine-induced wheal. Routinely serving as a control.

OBJECTIVE

Allergen-free polysorbate 80 containing (0.005%) test solutions were therefore systematically tested at different injection volumes to see whether polysorbate can falsify skin reactions and if yes whether conditions can be identified to avoid this.

METHODS

In a partly blinded study, 30 patients were tested intracutaneously at the back: each received at three separate sites 0.05 mL of polysorbate-containing solvent, 0.02 mL polysorbate-containing solvent as well as 0.02 mL polysorbate-free solvent. After 15 min, wheal and erythema were documented and planimetrically quantified.

RESULTS

Unexpectedly 23 of 30 (77%) patients showed false-positive test reactions to the volume of 0.05 mL of the polysorbate-containing solvent whereas the polysorbate-containing solvent with 0.02 mL and the polysorbate-free solvent with 0.02 mL injection volume had no reinforcing effect on skin test reaction.

CONCLUSIONS

Different volumes of polysorbate-containing solutions, all recommended by manufacturers for intradermal tests, may significantly influence test results. The study shows that a polysorbate 80 used at 0.005% in solvents for intradermal test to provide a better bioavailability of allergens produces false-positive reactivity in a surprising and a hitherto unknown 77% if the 0.05 mL volume is injected. It is, therefore, mandatory to strictly adhere to an intradermal test volume of 0.02 mL as only then falsifying effects of the polysorbate additive are avoided, and comparable test results are ensured.

International Consensus Statement on Allergy and Rhinology: Allergic Rhinitis

BACKGROUND

Critical examination of the quality and validity of available allergic rhinitis (AR) literature is necessary to improve understanding and to appropriately translate this knowledge to clinical care of the AR patient. To evaluate the existing AR literature, international multidisciplinary experts with an interest in AR have produced the International Consensus statement on Allergy and Rhinology: Allergic Rhinitis (ICAR:AR).

METHODS

Using previously described methodology, specific topics were developed relating to AR. Each topic was assigned a literature review, evidence-based review (EBR), or evidence-based review with recommendations (EBRR) format as dictated by available evidence and purpose within the ICAR:AR document. Following iterative reviews of each topic, the ICAR:AR document was synthesized and reviewed by all authors for consensus.

RESULTS

The ICAR:AR document addresses over 100 individual topics related to AR, including diagnosis, pathophysiology, epidemiology, disease burden, risk factors for the development of AR, allergy testing modalities, treatment, and other conditions/comorbidities associated with AR.

CONCLUSION

This critical review of the AR literature has identified several strengths; providers can be confident that treatment decisions are supported by rigorous studies. However, there are also substantial gaps in the AR literature. These knowledge gaps should be viewed as opportunities for improvement, as often the things that we teach and the medicine that we practice are not based on the best quality evidence. This document aims to highlight the strengths and weaknesses of the AR literature to identify areas for future AR research and improved understanding.

Natural history of skin prick test reactivity: A 20-year prospective study of a random population sample of children and adolescents

BACKGROUND

Allergic reactions to airborne allergens may have important consequences for affected individuals and are believed to be unstable through life, although evidence from longitudinal studies is limited.

OBJECTIVE

To assess changes in skin prick reactivity during 20 years in a random population sample of children and adolescents in relation to symptoms of rhinitis.

METHODS

A total of 983 individuals, aged 7 to 17 years, were randomly selected in 1986 and invited to 4 examinations during a 20-year period. During each examination, a skin prick test was performed using common local aeroallergens (ie, birch, grass, mugwort, horse, dog, cat, house dust mite [Dermatophagoides pteronyssinus and Dermatophagoides farinae] and 2 molds [Alternaria iridis and Cladosporium herbarum]).

RESULTS

The prevalence of allergy to any tested allergen peaked at the ages of 13 to 23 years. Rates of sensitization were variable. In the group of individuals tested more than once (n = 592), 16% developed sensitization during the study period and 9% became desensitized. In the group of individuals tested at all 4 examinations (n = 148), 34% developed sensitization and 22% became desensitized. In the group who developed sensitization, 55% had rhinitis, 17% had asthma, and 70% had eczema. In the group who became desensitized, 30% had rhinitis, 10% had asthma, and 50% had eczema.

CONCLUSION

This 20-year prospective study found that sensitization is common, but its prevalence in individuals is also variable over time. Furthermore, through puberty and early adulthood a large number of individuals develop sensitization and a smaller number become desensitized. In addition, we found that symptoms of rhinitis rarely preceded sensitization.

Diagnosis and treatment of allergic diseases in Zhejiang Province: a cross-sectional survey

BACKGROUND

The specialty of allergy developed quickly in western countries because of the rapid increase of allergic diseases, whereas it developed relatively slowly in China. The prevalence of allergen sensitization and allergic diseases in Zhejiang Province of China is high and improving the medical services for these diseases is critically needed.

OBJECTIVE

To investigate the working status of the diagnosis and treatment of allergic diseases, including doctor resources, diagnostic methods, and allergen-specific immunotherapy in patients of Zhejiang Province, and to provide instructions for the strategic development of subspecialties of allergic diseases.

METHODS

First we defined the doctors who treat allergic diseases, and designed a comprehensive questionnaire to collect personal and hospital information for these doctors. The questionnaires were distributed to hospitals with different ranks and from different areas in the province. The general condition of doctor's resources, carryout of diagnostic methods, and allergen-specific immunotherapy were described and variations in the different specialties, hospitals, and areas were further analyzed.

RESULTS

Doctors in their thirties with bachelor's degrees were the mainstream for diagnosing and treating allergic diseases. The main specialties of the doctor resources were the specialties of Ear, Nose and Throat (ENT), Respirology, Pediatrics, and Dermatology. The Pediatrics specialty had a more reasonable infrastructure of doctor resources with more young doctors working in this subspecialty. The development of allergy subspecialty varied within hospitals at different levels or from different areas. The carryout of the skin prick test (SPT), serum specific IgE (ssIgE), and subcutaneous immunotherapy (SCIT) was best performed in provincial hospitals, while sublingual immunotherapy (SLIT) was prescribed most commonly in municipal hospitals. The performance of SPT and ssIgE in Hangzhou, Jiaxing, and Wenzhou areas was much better than that in other places. The performance of SCIT and SLIT was best in Wenzhou.

CONCLUSIONS

Our survey revealed a very initial and unbalanced development for the allergy subspecialty in Zhejiang Province. Doctor resources for allergic diseases were mainly from the specialties of ENT, Respirology, and Pediatrics, and the performance of diagnosis and treatment was mainly focused on provincial and municipal hospitals. Continuous education of allergies could be extended to primary healthcare centers and more efforts should be directed to those areas with poor medical resources.