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ORIGINAL ARTICLE
Year : 2018  |  Volume : 32  |  Issue : 2  |  Page : 47-53

A study of skin sensitivity to various allergens by skin prick test in patients of bronchial asthma and allergic rhinitis


Department of TB and Respiratory Medicine, Geetanjali Medical College and Hospital, Udaipur, Rajasthan, India

Date of Web Publication12-Oct-2018

Correspondence Address:
Dr. Yash Mathur
Room No. 515, P G Hostel, Geetanjali Medical College and Hospital, Manvakheda, Udaipur - 313 002, Rajasthan
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/ijaai.ijaai_9_18

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  Abstract 

Background: Bronchial asthma (BA) and allergic rhinitis (AR) are among the most common allergic disorders. Identification of specific causative allergens is of paramount importance for further management.
Aims: This study aims (1) to find out the prevalence of various allergens leading to AR and/or BA through skin prick test (SPT), (2) to identify the trigger factors in these patients, (3) to study correlations of allergens and seasonal variations in patients suffering from AR and/or BA.
Materials and Methods: A total of 134 patients were collected from outpatient department and inpatient department of Respiratory Medicine Department of Geetanjali Medical College and Hospital, Udaipur, from January 2016 to December 2017. The diagnosis of BA and AR was made according to the GINA and ARIA guidelines, respectively. SPT was done with 78 different types of aeroallergens, which included 23 types of pollens, 6 types of fungi, 10 types of insects, 6 types of dusts, 6 types of dander, 3 fabrics, 2 feathers, and 22 food allergens. Patients who had taken short-acting oral antihistaminics, beta-blockers, steroids, tricyclic antidepressants or any other drug that could affect the test within one week prior to testing were excluded. Also, patients on long-acting oral antihistaminics within four weeks of testing and pregnant women were excluded.
Results: A total of 134 patients consisting of 73 (54.48%) males and 61 (45.52%) females, in the age group of 5–65 years, were included in the study. The maximum numbers of patients (50; 37.31%) were between the age group of 20 and 35 years. The maximum number of patients (94; 70.15%) had a duration of suffering from >1 years. AR was found in 60 (44.78%), BA associated with AR was found in 39 (29.1%), while BA alone was found in 35 (26.12%). In 54% of patients, triggers were found for exacerbation of their symptoms, the most common being air pollution (48%) followed by cold exposure (20%), physical activity (12%), irritants (9%), smoke (7%), and fumes and odors (4%). A total of 10,452 SPTs were done, out of which 265 (%) showed positive reactions. The positivity for pollens was seen in 116 (43.77%) patients followed by insects [79 (29.81%)], fungi [22 (8.3%)], house dust mite [15 (5.66%)], dusts [11 (4.15%)], fabrics [10 (3.77%)], danders [9 (3.4%)], and feathers [3 (1.13%)], respectively. Food allergens showed no significant reactions to SPT.
Conclusions: Our study showed that insects were the most common allergen in BA patients, while pollens were the most common allergen in patients of AR with or without BA. Intermittent symptoms were common with pollen allergy.

Keywords: Aeroallergen, allergic rhinitis, bronchial asthma, skin prick test


How to cite this article:
Sharma RK, Mathur Y, Chhabra G, Luhadia A, Luhadia SK, Dhandoria G. A study of skin sensitivity to various allergens by skin prick test in patients of bronchial asthma and allergic rhinitis. Indian J Allergy Asthma Immunol 2018;32:47-53

How to cite this URL:
Sharma RK, Mathur Y, Chhabra G, Luhadia A, Luhadia SK, Dhandoria G. A study of skin sensitivity to various allergens by skin prick test in patients of bronchial asthma and allergic rhinitis. Indian J Allergy Asthma Immunol [serial online] 2018 [cited 2018 Nov 13];32:47-53. Available from: http://www.ijaai.in/text.asp?2018/32/2/47/243230


  Introduction Top


Allergy is a hypersensitivity disorder of the immune system of the human body. Allergic reactions occur when a person's immune system reacts abnormally to normally harmless substances, present in the environment. A substance that causes a reaction is called an allergen.[1]

Asthma is a disease with many variations (heterogeneous), usually characterized by chronic airway inflammation. Asthmatic patients have two key defining features which are a history of respiratory symptoms such as wheeze, shortness of breath, chest tightness, and cough that vary over time and intensities and variable expiratory flow airflow limitations.[2]

Allergic rhinitis (AR) is an inflammation of the nasal membranes that is characterized by sneezing, nasal congestion, nasal itching and rhino rhea, in any combination. Although AR itself is not life-threatening (unless accompanied by severe asthma or anaphylaxis), morbidity from the condition can be significant.[3]

The burden of allergic diseases in India has been on an uprising trend in terms of prevalence as well as severity. It is estimated that 300 million people worldwide suffer from asthma, and this figure is projected to rise to 400 million by the year 2025.[2] Asthma accounts for approximately 500,000 hospitalizations each year,[4] with around 250,000 deaths annually attributed to the disease.[5] AR, previously regarded as a trivial disease, affects between 10% and 30% of all adults and as many as 40% of children.[5] The prevalence of rhinitis is around 35% in Europe and Australasia,[6] and it affects approximately 60 million people in the United States and its prevalence is increasing. A multicenter study by the Asthma Epidemiology Study Group of the Indian Council of Medical Research found the prevalence of bronchial asthma (BA) in Indian adults to be 2.38%.[7] In India, 20%–26% of people suffer from AR and symptoms of rhinitis were present in 75% of children and 80% of asthmatic adults.[8]

Aeroallergens are very often implicated in AR and asthma. They are usually classified as indoor (principally mites, pets, insects or from plant origin, e.g., ficus), outdoor (pollens and molds) or occupational agents. Classically, outdoor allergens appear to constitute a greater risk for seasonal rhinitis than indoor allergens and indoor allergens a greater risk for asthma and perennial rhinitis.[9],[10]

Patient's history and clinical examination are the primary modalities for identifying an allergic etiology and identifying the likely allergens responsible for the allergic symptoms. Diagnostic tests for detecting sensitizing allergen(s) of patients with IgE-mediated respiratory allergic disorders and identification of specific causative allergens are of paramount importance.[10]

Among various Diagnostic Tests for Detecting Sensitizing Allergen(s), skin prick test (SPT) is a reliable method to diagnose IgE-mediated allergic disease in patients with rhino-conjunctivitis, asthma, urticaria, anaphylaxis, atopic eczema, and suspected food and drug allergy. It provides evidence for sensitization and can help to confirm the diagnosis of a suspected type I allergy. It is minimally invasive and inexpensive, and results are immediately available and when carried out by trained health professionals, reproducible.[7] The position papers on skin tests by the European Academy of Allergy and Clinical Immunology and the US Joint Council of Allergy, Asthma and Immunology (American Academy of Allergy, Asthma and Immunology [AAAAI], ACAAI) state that properly performed prick test is the most convenient for better clinical correlation and is economical.[7] In addition, the World Allergy Organization has mentioned that SPT is the best screening method for detecting sIgE antibodies.[7]

They are highly reproducible when carried out by trained individuals.

In our Udaipur city and the surrounding regions, there is a wide variety of flora and fauna. Hence, patients suffering from AR and BA constitute a large fraction of patients coming to respiratory medicine outpatient department (OPD). The present study was done to study the skin sensitivity to various allergens by skin prick test in patients of AR and/or BA and also to identify the trigger factors in these patients.


  Materials and Methods Top


This clinical study was conducted in the Department of Respiratory Medicine, Geetanjali Medical College and Hospital, Udaipur, Rajasthan. A total of 134 patients were collected from OPD and inpatient department of Respiratory Medicine Department from January 2016 to December 2017. Diagnosis of BA and AR was made according to the GINA and ARIA guidelines, respectively. The sociodemographic and clinical variables were recorded in specific pro forma prepared for study. There was no associated history of tuberculosis, diabetes mellitus, hypertension, endocrine disease, or coronary artery disease. Pregnant females were excluded from the study. Hemogram, sputum, and chest radiography were done to rule out an alternative diagnosis.

A written informed consent was obtained from the participants before performing SPT. The antigens were obtained from All Cure Pharma Pvt. Ltd., New Delhi. The antigens included were 23 types of pollens, 6 types of fungi, 10 types of insects, 6 types of dusts, 6 types of dander, 3 fabrics, 2 feathers, and 22 food allergensPatients were counselled to stop drugs interfering with SPT according to the guidelines to achieve an appropriate diagnosis. Drop of each allergen was placed 3 cm apart and then was pricked with a lancet. Buffer saline will be used as a negative control while histamine acid phosphate (1 mg/ml) as a positive control. The wheel diameter was measured after 15–20 min and reported in “mm.” A skin reaction of ≥3 mm than that produced by the negative control on the SPT was considered as a positive reaction. The positive skin reactions which correlated well with the history were considered as clinically significant reactions.


  Results Top


A total of 134 patients consisting of 73 (54.48%) males and 61 (45.52%) females, in the age group of 5–65 years, were included in the study. The maximum numbers of patients (50; 37.31%) were between the age group of 20 and 35 years. The maximum number of patients (94; 70.15%) had a duration of suffering from >1 years. AR was found in 60 (44.78%), BA associated with AR was found in 39 (29.1%), while BA alone was found in 35 (26.12%) [Figure 1]. 69 (51.49%) had seasonal variation and rest 65 (48.51%) had perennial variation.
Figure 1: Allergic rhinitis was found in 60 (44.78%), bronchial asthma associated with allergic rhinitis was found in 39 (29.1%), while bronchial asthma alone was found in 35 (26.12%)

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We were able to find out triggers of 54% of patients on the basis of history, the most common being air pollution (48%) followed by cold exposure (20%), physical activity (12%), irritants (9%), smoke (7%), and fumes and odors (4%) [Figure 2].
Figure 2: Triggers of 54% of patients on the basis of history, the most common being air pollution (48%) followed by cold exposure (20%), physical activity (12%), irritants (9%), smoke (7%), and fumes and odors (4%)

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In our study, the entire 134 patients had a significant positive reaction to SPT. A total of 10,452 SPTs with 265 significant positive reactions were seen, from which pollens [116 (43.77%)] were the most common followed by insects [79 (29.81%)], fungi [22 (8.3%)], house dust mite [15 (5.66%)], dusts [11 (4.15%)], fabrics [10 (3.77%)], danders [9 (3.4%)], feathers [3 (1.13%)], respectively. Food allergens showed no significant reactions to SPT [Figure 3].
Figure 3: Among a total of 10,452 skin prick tests, 265 significant positive reactions were seen from which pollens [116 (43.77%)] were the most common followed by insects [79 (29.81%)], fungi [22 (8.3%)], house dust mite [15 (5.66%)], dusts [11 (4.15%)], fabrics [10 (3.77%)], danders [9 (3.4%)], feathers [3 (1.13%)], respectively. Food allergens showed no significant reactions to SPT

Click here to view


In our study from 265 positive SPT reactions, 124 positive reactions were seen in patients suffering from AR followed by 80 in patients having BA with AR (BA + AR) and 61 in patients of BA. Further in patients with AR with or without BA, pollens were the most common allergen, i.e., 45.16% and 48.75%, respectively, followed by insects, i.e., 30.65% and 22.50%, respectively, while in patients of BA alone, insects (37.7%) were the most common followed by pollens (34.43%) [Figure 4].
Figure 4: Positive reactions according to disease

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Out of 265 positive SPT reactions, 95 positive reactions were seen in patients in the age group of 20–35 years, and the most common reaction was from pollens [49 (51.58%)] followed by insects [23 (24.21%)]. 93 positive reactions were seen in the age group of 36–50 years, among which the most common reactions were from pollens [37 (39.78%)] followed by insects [32 (34.41%)]. 48 positive reactions were seen in the age group of >51 years, among which the most common reactions were from pollens [25 (52.08%)] followed by insects [7 (14.58%)]. 29 positive reaction were seen in the age group of <20 years, among which the most common reaction were from insects. In our study from 265 positive SPT reactions, 187 positive reactions were seen in patients with duration of illness >1 year, with the most common reaction from pollens [92 (49.2%)] and 78 positive reactions were seen in patients with duration of illness <1 year, with the most common reaction from insects [31 (39.74%)]. 133 positive reactions were seen in patients with perennial variation, with the most common reaction from insects [65 (48.87%)], and 132 positive reactions were seen in patients with seasonal variation, with the most common reactions from pollens [96 (72.73%)] [Figure 5].
Figure 5: Positive reactions according to variation

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In our study, among allergens, pollens (43.77%) were the most common allergen overall, and among pollens the most common was Holoptelea integrifolia [34 (29.31%)] followed by Dodonaea viscosa [13 (11.21%)], Parthenium hysterophorus and Prosopis juliflora [11 (9.48%)], and Morus alba[6 (5.17%)]. Among fungi (8.30%), the most common fungi were Aspergillus fumigatus [9 (40.91%)] followed by Aspergillus flavus and Aspergillus niger[6 (27.27%)] each. Among insects (29.81%), cockroach female [30 (37.97%)] was the most common followed by cockroach male [13 (16.46%)]. Among dusts (4.15%), the most common dust was grain dust wheat [5 (45.45%)] followed by grain dust bajara. Among danders (3.40%), the most common dander was cat [4 (44.44%)], cow [3 (33.33%)], and buffalo [2 (22.22%)]. Among fabrics (3.77%), the most common fabric was Kapok cotton [5 (50%)]. Among feathers (1.13%), the most common allergen was chicken [2 (66.67%)], followed by Pigeon 1 (33.33%) [Table 1].
Table 1: Allergen list with results

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  Discussion Top


AR with or without BA is a leading cause of morbidity world over, and the prevalence is gradually increasing in view of modernization and increasing environmental pollution.[2],[3] The various kinds of allergens are the most common trigger factors in these cases, and the recognition of allergens followed by allergen immunotherapy has been found to be quite effective in these cases.[10] Therefore, the identification of allergens is the initial step, and the treating physician should be aware of geographical distribution and prevalence of aeroallergen in a particular area.

A total of 134 patients consisting of 73 (54.48%) males and 61 (45.52%) females, in the age group of 5–65 years, were included in the study. The maximum numbers of patients (50; 37.31%) were between the age group of 20 and 35 years. The maximum number of patients (94; 70.15%) had duration of suffering from >1 years. Most of the previous studies have reported similar findings.[11],[12]

In our study, out of 134 patients studied, AR was found in 60 (44.78%), BA associated with AR was found in 39 (29.1%), while BA alone was found in 35 (26.12%). Majority of the previous studies have reported a wide variation in the above-mentioned conditions.[13],[14]

In our study, out of 134 patients, 69 (51.49%) had seasonal variation and rest 65 (48.51%) had perennial variation. Singh et al. in a study carried out on school children has reported intermittent AR in 35.6% while persistent allergic rhinitis was reported in 64.3%.[15] The higher proportion of patients with intermittent symptoms observed in our study may be because of the higher prevalence of pollen allergy in our cases.

In our study, we were able to find out triggers of 54% of patients on the basis of history, the most common being air pollution (48%) followed by cold exposure (20%), physical activity (12%), irritants (9%), smoke (7%), and fumes and odors (4%). Salvi et al. in 2015 showed that 49% of the asthmatics in the study reported that dust and air pollution were the most common asthma triggers.[16]

In our study, the entire 134 patients had a significant positive reaction to SPT. Out of a total of 10,452 SPTs, 265 significant positive reactions were seen of which pollens [116 (43.77%)] were the most common followed by insects [79 (29.81%)], fungi [22 (8.3%)], house dust mite [15 (5.66%)], dusts [11 (4.15%)], fabrics [10 (3.77%)], danders [9 (3.4%)], and feathers [3 (1.13%)], respectively. Food allergens showed no significant reactions to SPT. Matta et al.[17] have also reported pollens (62%) as the most common allergens in their study, while Kumar et al.[11] has reported insects (43.90%) as the most common aeroallergen in their study.

In our study from 265 positive SPT reactions, 124 positive reactions were seen in patients suffering from AR followed by 80 in patients having BA with AR (BA + AR) and 61 in patients of BA. Further in patients with AR with or without BA, pollens were most common allergen, i.e., 45.16% and 48.75%, respectively, followed by insects, i.e., 30.65% and 22.50%, respectively, while in patients of BA alone, insects (37.7%) were the most common followed by pollens (34.43%). However, few studies have reported insects and house dust mites as the most common allergens in patients having AR with or without BA.[11],[18] This appears to be a geographical variation.

In our study from 265 positive SPT reactions, 95 positive reaction was seen in patients of age group 20–35 years, and the most common reactions were from pollens [49 (51.58%)] followed by insects [23 (24.21%)]. Ninety-three positive reactions were seen in the age group of 36–50 years, with the most common reaction from pollens [37 (39.78%)] followed by insects [32 (34.41%)]. forty-eight positive reactions were seen in the age group of >51 years, with the most common reactions from pollens [25 (52.08%)] followed by insects [7 (14.58%)]. Twenty-nine positive reaction were seen in the age group of <20 years, among which the most common reactions were seen from insects. In our study from 265 positive SPT reactions, 187 positive reactions were seen in patients with duration of illness >1 year, with the most common reaction from pollens [92 (49.2%)] and 78 positive reactions were seen in patients with duration of illness <1 year, with the most common reaction from insects [31 (39.74%)]. So far, there is no study that has been reported which shows the prevalence of allergen according to age distribution and duration of illness.

In our study from 265 positive SPT reactions, 133 positive reactions were seen in patients with perennial symptoms and 132 positive reactions were seen in patients with seasonal variation. It was in accordance with studies by Brown et al.[19] and Sibbald and Rink.[20]

In our study among allergens, pollens (43.77%) were the most common allergen overall; among pollens, the most common was H. integrifolia 34 (29.31%) followed by D. viscosa [13 (11.21%)], P. hysterophorus and P. juliflora [11 (9.48%)], and M. alba [6 (5.17%)]. Similar results have been reported by Matta et al.[17] and Kumar et al.[11] Skin reactivity to fungi was seen in 8.3% of cases, with A. fumigatus being the most common [9 (40.91%)] followed by A. flavus and A. niger [6 (27.27%)] each. Among insects (29.81%), the most common insect was cockroach female [30 (37.97%)] followed by cockroach male [13 (16.46%)]. Among dusts (4.15%), the most common dust was grain dust wheat [5 (45.45%)] followed by grain dust bajara. Among danders (3.40%), the most common dander was cat [4 (44.44%)], cow [3 (33.33%)], and buffalo [2 (22.22%)]. Among fabrics (3.77%), the most common fabric was Kapok cotton [5 (50%)]. Among feathers (1.13%), the most common allergen was chicken [2 (66.67%)], followed by Pigeon 1 (33.33%). The results were in accordance with the study by Matta et al.[17] and the study by Podder et al. at Kolkata.[21]


  Conclusion Top


Our study shows that pollens are the most common aeroallergens followed by insects. The patients who had only BA showed insects as most common allergens, while patients with AR with or without BA showed a positive result with pollen allergy in most of the cases. Intermittent symptoms are common with pollen allergy.

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Conflicts of interest

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