Role of skin prick test in allergic disorders: a prospective study in kashmiri population in light of review

Pattern of skin sensitivity to various aeroallergens by skin prick test in patients of allergic airway disease in South Western Maharashtra

Background

The prevalence of allergic diseases such as asthma and allergic rhinitis is high in the general population, and aeroallergens are the most common allergens that cause airway inflammation. Skin prick testing (SPT) is a validated method to diagnose IgE-mediated allergic diseases. The knowledge of allergen sensitivity pattern in this part of India is limited. The present study was undertaken to identify common aeroallergens prevalent in this area using a standardized SPT.

Methods

We did a cross-sectional hospital-based study. A total of 330 patients of proven allergic airway disease underwent SPT. We used a validated skin prick test which included 22 allergen extracts, 1 positive control, and 1 negative control.

Results

A total of 327 patients were included in the study. Two hundred seventy-one (82.27%, n = 327) patients had a positive SPT to one or more aeroallergen extract. The sensitivity of Dermatophagoides pteronyssinus (49.85%) was seen in the maximum number of people followed by Dermatophagoides farinae (47.70%).

Conclusions

In our study, dust mites were the most common aeroallergen seen in maximum study subjects.

Study of Allergen Patterns in Cases of Moderate to Severe Persistent Allergic Rhinitis in Central India

The prevalence of Allergic rhinitis (AR) is associated with a variety of environmental allergens and the level of exposure is through inhalation, or ingestion. It is clear from several studies and guidelines that screening and identification of various allergens in a particular region can facilitate in diagnosing, treating and formulating preventive strategies against AR. To study the allergen patterns in patients with Moderate to severe persistent allergic rhinitis from Central India. Male/female of 6 to 63 years age group, presenting with itching of the nose, sneezing, rhinorrhoea, nasal congestion and nasal obstruction. Patients suffering from infective pathology of nose and sinuses. The study group comprised of 1350 male/female of the age group between 6 and 63 years. Modified skin prick test was performed according to the method of Pepys and Bernstein. The ratio of allergen wheal and histamine wheal was used to evaluate the results. The reactions with wheal diameter 3 mm or greater than the reading in the negative control were considered as positive reaction. Results of the study indicate that in Central India, the common allergens are pollens (78.5%), insects (64.5%), dust (38.5%), dust mites (18%) and food (10%) causing moderate to severe persistent allergic rhinitis. The study provided an insight and identified the allergen pattern in Central India. The results were of great help in counseling for avoidance therapy and for deciding allergen specific immunotherapy which is the standard treatment protocol to modify natural course of allergic rhinitis at this point of time.

Trends of sensitization pattern to aeroallergens among the patients with allergic rhinitis and/or bronchial asthma in Bangalore: A cross sectional study

Background

Allergic rhinitis (AR) is rather erroneously viewed as a trivial disease. It is a chronic or recurrent allergen-specific, IgE-mediated inflammation that primarily affects the membrane lining the nose. However, due to the united airway concept, it is also found to be associated with bronchial asthma. AR commonly remains underdiagnosed or misdiagnosed and thus, leads to either undertreatment or inappropriately prolonged medication.

Methods

Four hundred adults having allergic rhinitis and/or bronchial asthma, fulfilling the criteria as per Allergic Rhinitis and its Impact on Asthma (ARIA) guidelines, underwent skin prick test (SPT). Those having rhinitis due to nonallergic causes were excluded. SPT was carried out using a customized panel of 21 aeroallergens. The result was compared with the reaction of histamine, which was taken as a positive control.

Results

Majority of 228 (58.02%) of the patients showed a positive reaction to the tested panel of allergens. However, 165 (41.98%) showed no reaction to the tested panel of allergens can be due to various factors like reduced skin sensitivity, antihistaminic medications, etc.

Conclusion

Skin prick test accurate test for determining offending allergens in allergic conditions. House dust mites (41%) were the most common offending aeroallergen among patients with allergic rhinitis and/or bronchial asthma residing in Bangalore. The identification of offending aeroallergens have helped patients in avoiding unnecessary medications, take appropriate preventive measures or plan appropriate immunotherapy.

Identification of an allergenic calmodulin from Amaranthus palmeri pollen

INTRODUCTION

Pollens are an important source of allergens that trigger rhinitis or asthma. The allergenic extracts of pollens used to diagnose and treat allergies contain different allergenic antigens. Isolated allergenic proteins are employed in in vitro assays, skin tests and allergenic-specific immunotherapy. Calcium-binding allergens are clinically relevant antigens, and their allergenicity can be affected by Ca²⁺ binding. In this work, a calmodulin was identified as an allergen from Amaranthus palmeri pollen, an important source of pollinosis in Europe, Asia and North America.

MATERIALS AND METHODS

Allergenic calmodulin from A. palmeri pollen was isolated by size-exclusion chromatography and reverse-phase chromatography and identified by mass spectrometry. Sensitization to isolated calmodulin was evaluated by skin prick tests in patients with allergy to A. palmeri pollen.

RESULTS

Size-exclusion chromatography yielded two fractions that were recognized by the IgE of patients allergic to A. palmeri pollen. Mass spectrometry analysis of the fractions from reverse-phase chromatography showed peptide sequences that identified a calmodulin. Skin prick tests showed that the isolated calmodulin was recognized by 56% of patients allergic to A. palmeri pollen.

CONCLUSION

A. palmeri pollen calmodulin could be a clinically relevant allergen in patients sensitized to this source.

Molecular and immunochemical characterization of Pop n 2: A new allergen of Populus nigra pollen

BACKGROUND

Pollen is one of the most common allergens that cause respiratory allergies worldwide. Pollen grains from poplars have been reported as important sources of pollinosis in many countries.

OBJECTIVE

The aim of the present study was to determine the molecular and immunochemical characterization of Pop n 2, a novel allergen of Populus nigra (P nigra) pollen extract.

METHODS

In this study, the pollen extract of P nigra was analysed by SDS-PAGE, and the allergenic profile was determined by IgE immunoblotting and specific ELISA using the sera of twenty allergic patients. The coding sequence of Pop n 2 was cloned and expressed in the Escherichia coli BL21 (DE3) using plasmid the pET-21b (+). Finally, the expressed recombinant Pop n 2 was purified by affinity chromatography.

RESULTS

Pop n 2 belongs to the profilin family with a molecular weight of approximately 14 kDa. Pop n 2 is the most IgE-reactive protein (about 65%) in the P nigra pollen extract. The cDNA sequencing results indicated an open reading frame 396 bp that encodes 131 amino acid residues. The results of ELISA and Immunoblotting assays showed that recombinant Pop n 2 could react with the IgE antibody in patients' sera, like its natural counterpart.

CONCLUSION

Our data revealed that Pop n 2 is a significant allergen in the P nigra pollen extract. Moreover, we observed that the recombinant Pop n 2 produced by the pET-21b (+) vector in the E colisystem acts as its natural counterpart.

Skin prick reactivity among asthmatics in East Africa

Background

The burden of asthma in Africa is high, and yet the disease is not universally prioritised. Data on allergic asthma and its impact on asthma morbidity are limited in Africa. Our aim was to describe the distribution of skin prick positivity among asthmatics in Eastern Africa.

Methods

From August 2016 to May 2018, 1671 asthmatic patients were enrolled from Uganda, Kenya, and Ethiopia as part of the African Severe Asthma Program clinical study. Skin prick testing was performed at baseline using a panel of 12 allergens, and factors associated with skin prick reactivity determined.

Results

Of the 1, 671 patients recruited, 71% were female with a median age of 40 years, 93.6% were aged >15 years and the patterns of asthma symptom frequency was intermittent in 2.9%, mild persistent in 19.9%, moderate persistent in 42.6% and severe persistent in 34.6% at baseline. Self-reported triggers, were dust (92%), cold weather (89%), upper respiratory infections (84%), strong smells (79%) and exposure to tobacco (78%). The majority (90%) of the participants had at least 1 positive allergen reaction, with 0.9% participants reacting to all the 12 allergens. Participants commonly reacted to house dust mites (66%), Blomia tropicalis (62%), and the German cockroach (52%). Patients sensitized to more allergens (>2) had significantly reduced lung function (FEV ≤ 80%; p = 0.001) and were more likely to visit the emergency department due to asthma (p = 0.012). There was no significant relationship between number of allergens and measures of asthma control, quality of life, and other clinical outcomes. Only the country of origin was independently associated with atopy among African asthmatics.

Conclusion

There is a high prevalence of skin prick positivity among East African patients with asthma, with the commonest allergen being house dust mite. Skin reactivity did not correlate well with asthma severity and poor asthma control. The relation between atopy, measured through skin prick testing, and measures of asthma control among asthma patients in Eastern Africa is unclear and needs further study.

Trial registration

The ASAP study was registered prospectively. ClinicalTrials.gov Identifier: NCT03065920; Registration date: February 28, 2017; Last verified: February 28, 2017.

Microbial interactions in the atopic march

The human body is populated by a large number of microorganisms and exist in symbiosis with these immensely diverse communities, which are suggested to influence health and disease. The microbiota plays an essential role in the maturation and function of the immune system. The prevalence of atopic diseases has increased drastically over the past decades, and the co-occurrence of multiple allergic diseases and allergic sensitization starting in early life has gained a great deal of attention. Immune responses in different organs affected by allergic diseases (e.g. skin, intestine and lung) may be linked to microbial changes in peripheral tissues. In the current review, we provide an overview of the current understanding of microbial interactions in allergic diseases and their potential role in the atopic march.

The Most Common Allergenic Tree Pollen Grains in the Middle East: A Narrative Review

Allergy is becoming a major disease burden globally. Pollens are considered as the main component of aeroallergens that lead to rhinitis and asthma. Due to the lack of a comprehensive investigation on most allergic pollens of trees in the Middle East, the present study aimed to conduct a comprehensive literature review on this topic. The main goal of the study was to provide a checklist for allergists and patients to easily identify the commonest allergic pollens in their locality. The present review provides a broad range of information on the types and geographic locations of the most common allergic pollens of trees in each studied country. In general, among the 23 studied countries, palm and mesquite trees were the common producers of pollen allergen in the Persian Gulf region. Olive tree is common in Turkey, Palestine, and Israel, whereas sycamore tree is the common allergen pollen in Iran. Considering the uneven geographical distribution of these trees in the world, allergists are unable to accurately select the appropriate extracts for the skin prick test based on the information from the neighboring countries. This scenario becomes more complicated if one adds the imported ornamental trees in the picture.

Skin prick/puncture testing in North America: a call for standards and consistency

BACKGROUND

Skin prick/puncture testing (SPT) is widely accepted as a safe, dependable, convenient, and cost-effective procedure to detect allergen-specific IgE sensitivity. It is, however, prone to influence by a variety of factors that may significantly alter test outcomes, affect the accuracy of diagnosis, and the effectiveness of subsequent immunotherapy regimens. Proficiency in SPT administration is a key variable that can be routinely measured and documented to improve the predictive value of allergy skin testing.

METHODS

Literature surveys were conducted to determine the adherence to repeated calls for development and implementation of proficiency testing standards in the 1990's, the mid-2000's and the 2008 allergy diagnostics practice parameters.

RESULTS

Authors publishing clinical research in peer-reviewed journals and conducting workshops at annual scientific meetings have recommended proficiency testing based primarily on its potential to reduce variability, minimize confounding test results, and promote more effective immunotherapeutic treatments. Very few publications of clinical studies, however, appear to report proficiency testing data for SPT performance. Allergen immunotherapy recommendations are updated periodically by the Joint Task Force on Practice Parameters representing the American Academy of Allergy, Asthma and Immunology (AAAAI), the American College of Allergy, Asthma and Immunology (ACAAI), and the Joint Council of Allergy, Asthma and Immunology (JCAAI).

CONCLUSIONS

Despite consensus that all staff who perform SPT should meet basic quality assurance standards that demonstrate their SPT proficiency, the gap between recommendations and daily practice persists. By embracing standards, the accuracy of SPT and allergy diagnosis can be optimized, ultimately benefiting patients with allergic disease.

Hypersensitivity to aeroallergens in patients with nasobronchial allergy

Background:

Aeroallergens are the most common causes of allergy.

Aim:

The aim of this study was to determine hypersensitivity to aeroallergens in patients with nasobronchial allergy.

Methods:

This retrospective population study included 2254 patients with nasobronchial allergy, from late adolescents to adults. Their response to aeroallergens was assessed by skin prick tests.

Results:

More patients had rhinitis (72.7%), than asthma (27.6%). Although majority of patients were female, allergy is more common in men than in women (p<0.05). Both groups of patients had the greatest number of positive skin prick tests for Dermatophagoides pteronyssinus (27.5%) and weed pollens (21.9%), followed by grass (18.3%) and tree pollens (10.1%). Ragweed is the most common positive weed pollen in both groups, more in patients with rhinitis (p=0.022). The cocksfoot is the most common grass pollen in rhinitis group (15.3%), but meadow grass (12.6%) in asthma patients. Birch is the most common tree allergen in the both groups.

Conclusions:

More patients with nasobronchial allergy have rhinitis than asthma. Skin prick tests are usually positive for Dermatophagoides pteronyssinus and weed pollens, followed by grass and tree pollens, and they are more common positive in patients with rhinitis than asthma.