Relationship between skin prick and atopic patch test reactivity to aeroallergens and disease severity in children with atopic dermatitis

The Role of Inhalant Allergens on the Clinical Manifestations of Atopic Dermatitis

BACKGROUND

Inhalant allergens provide a source of environmental factors that contribute to the development of clinical symptoms in patients with atopic dermatitis (AD).

OBJECTIVE

To review the relationship between inhalant allergens and AD.

METHODS

A literature review was conducted using three databases: PubMed/MEDLINE, ClinicalKey, and Web of Science. Search terms, including "atopic dermatitis," "atopic eczema," and "eczema," were used in combination with "inhalant allergen," "inhaled allergen," and "aeroallergen" to identify relevant published manuscripts that highlight the relationship between AD and exposures to inhalant allergens.

RESULTS

Fifteen articles were suitable for review. The studies included in the review investigated the effect of inhalant allergens on the clinical manifestations of AD through bronchial provocation, direct skin contact, and allergen sensitization.

CONCLUSION

There is a significant relationship between exposures to inhalant allergens and AD. Inhalant allergens may aggravate AD symptoms by either bronchial provocation or direct skin contact. Sensitization of inhalant allergens, mainly house dust mites, follows a specific age-related pattern.

The immunological and structural epidermal barrier dysfunction and skin microbiome in atopic dermatitis-an update

Atopic dermatitis (AD) is a common, chronic and relapsing inflammatory skin disease with various clinical presentations and combinations of symptoms. The pathophysiology of AD is complex and multifactorial. There are several factors involved in the etiopathogenesis of AD including structural and immunological epidermal barrier defect, imbalance of the skin microbiome, genetic background and environmental factors. Alterations in structural proteins, lipids, proteases, and their inhibitors, lead to the impairment of the stratum corneum which is associated with the increased skin penetration and transepidermal water loss. The elevated serum immunoglobulin E levels and blood eosinophilia have been shown in the majority of AD patients. Type 2 T-helper cell immune pathway with increased expression of interleukin (IL)-4, IL-5, and IL-13, has an important role in the etiopathogenesis of AD. Both T cells and keratinocytes contribute to epidermal barrier impairment in AD via a dynamic interaction of cytokines and chemokines. The skin microbiome is another factor of relevance in the etiopathogenesis of AD. It has been shown that during AD flares, Staphylococcus aureus (S. aureus) colonization increased, while Staphylococcus epidermidis (S. epidermidis) decreased. On the contrary, S. epidermidis and species of Streptococcus, Corynebacterium and Propionibacterium increased during the remision phases. However, it is not clear whether skin dysbiosis is one of the symptoms or one of the causes of AD. There are several therapeutic options, targeting these pathways which play a critical role in the etiopathogenesis of AD. Although topical steroids are the mainstay of the treatment of AD, new biological therapies including IL-4, IL-13, and IL-31 inhibitors, as well as Janus kinase inhibitors (JAKi), increasingly gain more importance with new advances in the therapy of AD. In this review, we summarize the role of immunological and structural epidermal barrier dysfunction, immune abnormalities, impairment of lipids, filaggrin mutation and skin microbiome in the etiopathogenesis of AD, as well as the therapeutic options for AD and their effects on these abnormalities in AD skin.

Genetic/Environmental Contributions and Immune Dysregulation in Children with Atopic Dermatitis

Atopic dermatitis (AD) is one of the most common skin conditions in humans. AD affects up to 20% of children worldwide and results in morbidity for both patients and their caregivers. The basis of AD is an interplay between genetics and the environment characterized by immune dysregulation. A myriad of mutations that compromise the skin barrier and/or immune function have been linked to AD. Of these, filaggrin gene (FLG) mutations are the most evidenced. Many other mutations have been implicated in isolated studies that are often unreplicated, creating an archive of genes with potential but unconfirmed relevance to AD. Harnessing big data, polygenic risk scores (PRSs) and genome-wide association studies (GWAS) may provide a more practical strategy for identifying the genetic signatures of AD. Epigenetics may also play a role. Staphylococcus aureus is the most evidenced microbial contributor to AD. Cutaneous dysbiosis may result in over-colonization by pathogenic strains and aberrant skin immunity and inflammation. Aeroallergens, air pollution, and climate are other key environmental contributors to AD. The right climate and/or commensals may improve AD for some patients.

Aeroallergens in Atopic Dermatitis and Chronic Urticaria

PURPOSE OF REVIEW

While aeroallergens are a well-established trigger of asthma and allergic rhinitis, their role in allergic skin diseases such as atopic dermatitis and chronic urticaria remains controversial. This paper reviews the pathophysiology and clinical evidence for aeroallergens in these allergic skin diseases and summarizes current strategies for evaluation and management.

RECENT FINDINGS

Current evidence implicates aeroallergens as triggers of cutaneous reactions in atopic dermatitis. Direct skin contact is the likely route of trigger. Aeroallergens may also trigger chronic urticaria, though mechanistic studies are limited. These allergens may cross the skin barrier and directly trigger neurons to release substance P, resulting in mast cell degranulation and dumping of histamine and prostaglandin D2. Many studies link aeroallergen sensitization to chronic urticaria, and case reports suggest the utility of avoidance strategies. The role of aeroallergens as a trigger is clear in atopic dermatitis and becoming emergent in chronic urticaria. Skin prick testing or serum-specific immunoglobulin E testing may be used to determine sensitivities. Management at this time centers on avoidance, and further studies are necessary to evaluate the efficacy of aeroallergen immunotherapy for both conditions.

The skin prick test response after allergen immunotherapy in different levels of tIgE children with mite sensitive Asthma/Rhinitis in South China

BACKGROUND

At present, the biomarkers which can predict the clinical efficacy of allergen immunotherapy (AIT) are still much debated. IgE levels are often related to allergic severity. Therefore, this study aimed at relating total IgE (tIgE) levels with the efficacy of AIT assessed by symptoms and drug score and skin prick test (SPT) response.

METHODS

We evaluated 81 allergic children who had received house-dust mite (HDM) subcutaneous immunotherapy for three years. According to the tIgE levels before treatment, all children were divided into high value, medium value and low value group. Each group according to sIgE/tIgE ratio was divided into subgroups. The efficacy of AIT is assessed by symptoms and drug score. By comparing changes in the grade of SPT in each group, the response of AIT are evaluated.

RESULTS

The SPT grade changes to determine efficacy had a high degree of consistency with symptoms and drug score judgment (sensitivity 89.7%, specificity 78.3%, Kappa = 0.670, P < 0.001). Compared to ineffective cases, the effective cases had lower tIgE (P < 0.001) and higher ratio of sIgE/tIgE (P < 0.001). The grades of SPT declined the most in the low value group (low value group vs. medium value group, P < 0.05; low value group vs. high value group, P < 0.001; medium value group vs. high value group, P < 0.05).

CONCLUSIONS

The SPT grade change can be used for efficacy evaluation. Children with lower level of tIgE and higher ratio of sIgE/tIgE that obtain a more satisfactory effect.

Comparison of atopy patch testing to skin prick testing for diagnosing mite-induced atopic dermatitis: a systematic review and meta-analysis

BACKGROUND

Atopic dermatitis (AD) can occur after contact with aeroallergens like house dust mites, pollen, and animal dander. Despite its controversial diagnostic value, the atopy patch test (APT) has been used as an important tool in the diagnosis of AD caused by house dust mites. Here, we present a meta-analysis comparing APT to the common skin prick test (SPT) in the diagnosis of mite-induced AD.

METHODS

A structured search was performed using online databases and bibliographies published as of April 30, 2017. All studies evaluating the accuracy of APT and SPT in the diagnosis of mite-induced atopic eczema/dermatitis syndrome were selected, appraised, and data was extracted.

RESULTS

Ten studies were identified for inclusion in our analysis. Meta-analysis revealed that the pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratios for APT were 0.54 (95% CI 0.42-0.66), 0.72 (95% CI 0.56-0.85), 1.97 (95% CI 1.20-3.23), 0.63 (95% CI 0.48-0.83), and 3.12 (95% CI 1.53-6.39). The area under the summary receiver operating characteristic curve was 0.65 (95% CI 0.61-0.69).

CONCLUSIONS

Our analysis indicates that APT is a useful tool in the screening of mite-induced AD, although this conclusion must be interpreted cautiously due to high heterogeneity among the included studies.

Atopy patch test in children with atopic dermatitis

BACKGROUND

Atopic dermatitis is frequently associated with food and/or aeroallergen allergy.

OBJECTIVE

To evaluate atopy patch tests (APTs) and skin prick tests (SPTs) in children with atopic dermatitis, using allergen extracts from locally lyophilized foods (cow's milk, egg white, egg yolk, wheat, soy, and shrimp), Dermatophagoides pteronyssinus, Dermatophagoides farinae, and American cockroach.

METHODS

This study was a prospective, self-controlled study in children with atopic dermatitis. APTs, SPTs, and oral food challenge tests were performed in the cases with written informed consent.

RESULTS

Fifty-six children with atopic dermatitis were enrolled. According to the Severity Scoring of Atopic Dermatitis Index, moderate atopic dermatitis was the most common severity (49.1%) followed by mild (20%) and severe atopic dermatitis (13.2%). APT results were positive for food allergens in 49% of participants; SPT results were positive in 54.7%. The sensitivity, specificity, positive predictive value, and negative predictive value of APTs for foods were 40%, 90.2%, 65.2%, and 76.6%, respectively. For SPTs, those values were 40%, 93.9%, 75%, and 77.3%, respectively. APT results for D farinae, D pteronyssinus, and American cockroach were positive in 33.9%, 35.8%, and 21.8% of participants, respectively. SPT results for these allergens were positive in 28.3%, 24.5%, and 9.4% of participants, respectively. No serious complications occurred.

CONCLUSION

APTs with locally prepared lyophilized allergen extracts were safe and had high specificity, median positive predictive value, and low sensitivity for evaluation of suspected food allergy in children with atopic dermatitis.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT01164293.

Adenoid Vegetation in Children with Allergic Rhinitis

Objective

Pediatric patients with nasal obstruction due to adenoid vegetation (AV) can also encounter allergic rhinitis (AR) as a comorbidity. The aim of the study was to estimate the incidence of mite sensitization and its effect on adenoid size in children who underwent adenoidectomy.

Methods

This prospective randomized study conducted between August and September 2014 included 84 children. Skin Prick Test (SPT) for inhalant allergens was preoperatively applied to all children who underwent adenoidectomy for nasal obstruction. Children were divided into two study groups: AV only (Group I) (n=52) and AV with Dermatophagoides Pteronyssinus and/or D. farinae allergy (Group II) (n=32). Postoperative specimen volumes, visual analogue scale (VAS) scores, and adenoid volumes measured using flexible fiberoptic nasopharyngolaryngoscopy were compared between the two groups.

Results

Postoperative specimen volume measures were higher in Group II compared with those in Group I (p<0.05). Furthermore, in preoperative endoscopic examination, adenoid volume measures were higher in Group II compared with those in Group I (p<0.05). Pre and postoperative VAS scores in SPT+ group were higher in the Group II (p<0.05) than those in Group I.

Conclusion

We observed that children with AR tend to have an early onset of symptoms of adenoid hypertrophy. We believe that focusing on the management of role of allergy regarding these early symptoms will reduce the need for surgery in a large number of cases. We suggest that SPT must be performed in all children with AV and adenoid examination should not be neglected in children with AR.

Cigarette Smoking and Skin Prick Test in Patients With Allergic Rhinitis

Background:

Allergic Rhinitis (AR) is the most common allergic disease, affecting 30% of population around the world. The disease is predominantly associated with exposure to some aeroallergens like cigarette smoking. Skin Prick Test (SPT) is a method of detecting immediate allergic reactions and is applied for controlling disease and therapeutic modality.

Objectives:

This study was designed to investigate the effect of cigarette smoking on SPT results among male and female individuals with AR disease.

Patients and Methods:

A total of 478 patients with AR admitted to the 2 main hospitals of Zahedan City from 2005 to 2012, were recruited in this analytic-descriptive study. Categories of smokers and never smokers were used based on patient’s statements and their history of smoking. SPT was performed with panel of some allergens and results were recorded and analyzed statistically. Odds ratio and confidence interval method were calculated using univariate logistic regression.

Results:

The results of this study indicated that 41.4% of patients with allergic rhinitis was smoker with ages ranged from 15 to 70 years. The result of this study also showed that smoking has no effect on SPT results of pollen and weeds aeroallergens conducted on male and female AR patients. However, male were significantly more sensitive than female in terms of sensitivity to the aspergillus, cladosporium, house dust mite, grasses, wheat, cockroach, and feather allergens.

Conclusions:

Our findings did not support the effect of cigarette smoking on SPT reactivity to pollen and weeds aeroallergens. However, male were significantly more sensitive than female in terms of sensitivity to some allergens.