Allergy testing on the IMMULITE 2000 Random-Access immunoanalyzer – a clinical evaluation study

Author(s):  
Christa M. Cobbaert ◽  
Geert Jan Jonker

AbstractPurpose: We aimed to evaluate the diagnostic performance of the IMMULITE 2000 Allergy System from Diagnostic Products Corporation (DPC) for the detection of inhalant and food allergies, focusing on inhalant and food screens, mixes and single allergens.Methods: Serum samples were collected from new, unselected patients who were referred to the allergist for a suspected allergy. Patients were classified as study diagnosis-positive for inhalant (food) allergy if they had both a positive clinical examination/history and a positive skin test for inhalant (food) allergy; otherwise – failing one or both of these criteria – they were classified as study diagnosis-negative. Classification and testing of the serum samples was carried out in a blinded fashion. Values greater than 0.35 kU/L were considered positive.Results: Of the 118 patients included, 63 were considered study diagnosis-positive for inhalation and/or food allergy. DPC inhalation screening showed 82% total agreement (TA) and 91% sensitivity relative to the study diagnoses. The DPC food panel showed 96% TA and 98% specificity relative to the study diagnoses. Relative to specific intracutaneous testing (ICT), the DPC D1, E1 and E5 assays had sensitivity of 82–90%; tree and grass panels had sensitivity of 74% and 95%. The DPC weed panel and initial lots of DPC E5 had poor sensitivity (<40%); mold panel sensitivity was equally low for both DPC and the routinely used Pharmacia assay (36%). Relative to skin prick testing (SPT), specific food allergens had TA of 94–98% and specificity of 95–100%.Conclusion: In patients classified by the combination of clinical examination/history and skin test results, the DPC IMMULITE 2000 Allergy System generally demonstrated acceptable sensitivity, specificity and TA compared to the study diagnoses, both at the screening level and at the level of panels and single allergens.

2020 ◽  
Vol 14 (1) ◽  
pp. 46-52
Author(s):  
Akefeh Ahmadiafshar ◽  
Mohammad Vafaee-Shahi ◽  
Saeide Ghasemi ◽  
Fariba Khosroshahi ◽  
Aina Riahi

Background: Headache and particularly migraine headaches are considered as a debilitating disease worldwide that can adversely affect the quality of life of children and adults. Various factors can play a critical role in the development of migraine headache attacks. The food allergens are considered as important factors. This study aimed to determine the frequency of food allergy in children with migraine headaches. Methods: Forty patients aged <16 years with a migraine headache were entered into the study. A questionnaire was provided in which data on demographic information and skin test results for various allergens were recorded. Dietary allergies were defined based on a positive skin test plus a patient's history of food allergies. The severity of migraine was evaluated using the Migraine disability assessment score (MIDAS) questionnaire. Results: The present study showed 32.5% of our participants had a food allergy. No significant association was detected between sex (p=58) and age (p=0.14) with food allergy. However, the frequency of food allergy was significantly higher in patients aged ≥12 years old (44.4%) than those aged <12 (22.7%). A significant relationship was found between the number of attacks after prophylaxis and the frequency of food allergies (p=0.032). Individuals with lower attacks had a lower food allergy. Conclusion: Our findings revealed that about one-third of children with a migraine headache had a food allergy. This frequency was significantly higher in children with migraines than that of the general population based on the results of previous studies. It is recommended that these patients receive a skin allergy test while preparing a strong history of food allergies or when the frequency of migraine attacks does not decrease significantly despite proper prophylaxis.


2018 ◽  
Vol 58 (2) ◽  
pp. 59-65
Author(s):  
Camilia Metadea Aji Savitri ◽  
Azwin Mengindra Putera Lubis ◽  
Gatot Soegiarto

Background Food allergy is common in children and its prevalence is generally on the rise. Imprecise parental reports about reactions to particular foods can lead to unnecessary restrictions. Since children have specific growth requirements, such nutritional restrictions may have disturbing effects on children’s growth and development.Objective To compare parental reports on food reactions to skin prick test results in their children.Method Retrospective, cross sectional study using patient’s medical record data during one-year study period. Data were analyzed manually and statistically, to assess the degree of agreement (Kappa’s coefficient) and significance (P).Results We collected data from 154 subjects aged 0-18 years. For every allergen assessed, parents reported more food reactions than positive skin prick test results. Allergy incidence were caused, in order, by cow’s milk and chicken (25.3%), eggs (22.1%), chocolate (20.1%), fruits (14.3%), seafood (13%), and saltwater fish (1.9%). Kappa coefficient are all poor (<0.2) and P value are all >0.05 except for chicken (P=0.02).Conclusion Most parents tend to overestimate which food cause reactions in their children, as reactions reported were not necessarily allergenic. Therefore, every patient experiencing allergy reactions should undergo skin prick testing to confirm the possibility of allergy.


2016 ◽  
Vol 7 (4) ◽  
pp. ar.2016.7.0183 ◽  
Author(s):  
Javier Domínguez-Ortega ◽  
María Ángeles López-Matas ◽  
María Dolores Alonso ◽  
Angélica Feliu ◽  
Javier Ruiz-Hornillos ◽  
...  

Background Sensitization to Finales (Cupressaceae and Pinaceae) has increased dramatically in recent years. The prevalence of sensitization in different geographic areas is related to exposure to specific pollens. Objectives To investigate the prevalence of allergy to different conifer pollens, describe the characteristics of patients with such allergy, and identify the involved allergens. Methods Patients were recruited at five hospitals near Madrid. Extracts from conifer pollen were prepared and used in skin-prick testing. Wheal sizes were recorded, and serum samples obtained from patients with positive reactions to Cupressus arizonica and/or Pinus pinea. The specific immunoglobulin E value to C. arizonica and Cup a 1 was determined. Individual immunoblots for each patient and with a pool of sera were performed. Allergenic proteins were sequenced by using liquid chromatography-tandem mass spectrometry. Results Of 499 individuals included in the study, 17 (14%) had positive skin-prick test results to some conifer pollen extracts. Sixty-four patients had positive results to C. arizonica (prevalence 12.8%) and 11 had positive results to P. pinea (2.2%). All the patients had respiratory symptoms (61.4% during the C. arizonica pollination period), and 62.9% had asthma. Approximately 86% of the patients had positive specific immunoglobulin E results to C. arizonica and 923% had positive results to Cup a 1. Fourteen different bands were recognized by immunoblot; the most frequent bands were those detected at 43, 18, 16, and 14 kDa. All sequenced proteins corresponded to Cup a 1. Conclusion Allergy to conifer pollen could be considered a relevant cause of respiratory allergy in central Spain. Asthma was more frequent than in other studies. We only identified Cup a 1 as involved in sensitization.


Author(s):  
Kate W. Sjoerdsma ◽  
W. James Metzger

Eosinophils are important to the pathogenesis of allergic asthma, and are increased in bronchoalveolar lavage within four hours after bronchoprovocation of allergic asthmatic patients, and remain significantly increased up to 24 hours later. While the components of human eosinophil granules have been recently isolated and purified, the mechanisms of degranulation have yet to be elucidated.We obtained blood from two volunteers who had a history of allergic rhinitis and asthma and a positive skin test (5x5mm wheal) to Alternaria and Ragweed. Eosinophils were obtained using a modification of the method described by Roberts and Gallin.


2019 ◽  
Vol 40 (6) ◽  
pp. 450-452 ◽  
Author(s):  
Ashley L. Devonshire ◽  
Rachel Glick Robison

Primary prevention and secondary prevention in the context of food allergy refer to prevention of the development of sensitization (i.e., the presence of food-specific immunoglobulin E (IgE) as measured by skin-prick testing and/or laboratory testing) and sensitization plus the clinical manifestations of food allergy, respectively. Until recently, interventions that target the prevention of food allergy have been limited. Although exclusive breast-feeding for the first 6 months of life has been a long-standing recommendation due to associated health benefits, recommendations regarding complementary feeding in infancy have significantly changed over the past 20 years. There now is evidence to support early introduction of peanut into the diet of infants with egg allergy, severe atopic dermatitis, or both diagnoses, defined as high risk for peanut allergy, to try to prevent development of peanut allergy. Although guideline-based recommendations are not available for early introduction of additional allergenic foods, this topic is being actively studied. There is no evidence to support additional dietary modification of the maternal or infant diet for the prevention of food allergy. Similarly, there is no conclusive evidence to support maternal avoidance diets for the prevention of food allergy.


Cells ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1586
Author(s):  
Tomoe Yashiro ◽  
Hanako Ogata ◽  
Syed Faisal Zaidi ◽  
Jaemin Lee ◽  
Shusaku Hayashi ◽  
...  

Recently, the involvement of the nervous system in the pathology of allergic diseases has attracted increasing interest. However, the precise pathophysiological role of enteric neurons in food allergies has not been elucidated. We report the presence of functional high-affinity IgE receptors (FcεRIs) in enteric neurons. FcεRI immunoreactivities were observed in approximately 70% of cholinergic myenteric neurons from choline acetyltransferase-eGFP mice. Furthermore, stimulation by IgE-antigen elevated intracellular Ca2+ concentration in isolated myenteric neurons from normal mice, suggesting that FcεRIs are capable of activating myenteric neurons. Additionally, the morphological investigation revealed that the majority of mucosal mast cells were in close proximity to enteric nerve fibers in the colonic mucosa of food allergy mice. Next, using a newly developed coculture system of isolated myenteric neurons and mucosal-type bone-marrow-derived mast cells (mBMMCs) with a calcium imaging system, we demonstrated that the stimulation of isolated myenteric neurons by veratridine caused the activation of mBMMCs, which was suppressed by the adenosine A3 receptor antagonist MRE 3008F20. Moreover, the expression of the adenosine A3 receptor gene was detected in mBMMCs. Therefore, in conclusion, it is suggested that, through interaction with mucosal mast cells, IgE-antigen-activated myenteric neurons play a pathological role in further exacerbating the pathology of food allergy.


Children ◽  
2021 ◽  
Vol 8 (6) ◽  
pp. 497
Author(s):  
Aikaterini Anagnostou

Background: Food allergies are common, affecting 1 in 13 school children in the United States and their prevalence is increasing. Many misconceptions exist with regards to food allergy prevention, diagnosis and management. Objective: The main objective of this review is to address misconceptions with regards to food allergies and discuss the optimal, evidence-based approach for patients who carry this diagnosis. Observations: Common misconceptions in terms of food allergy prevention include beliefs that breastfeeding and delayed introduction of allergenic foods prevent the development of food allergies. In terms of diagnosis, statements such as ‘larger skin prick tests or/and higher levels of food-specific IgE can predict the severity of food-induced allergic reactions’, or ‘Tryptase is always elevated in food-induced anaphylaxis’ are inaccurate. Additionally, egg allergy is not a contraindication for receiving the influenza vaccine, food-allergy related fatalities are rare and peanut oral immunotherapy, despite reported benefits, is not a cure for food allergies. Finally, not all infants with eczema will develop food allergies and epinephrine auto-injectors may unfortunately be both unavailable and underused in food-triggered anaphylaxis. Conclusions and relevance: Healthcare professionals must be familiar with recent evidence in the food allergy field and avoid common misunderstandings that may negatively affect prevention, diagnosis and management of this chronic disease.


2006 ◽  
Vol 27 (5) ◽  
pp. 436-441 ◽  
Author(s):  
Lloyd N. Friedman ◽  
Esther R. Nash ◽  
June Bryant ◽  
Susan Henry ◽  
Julia Shi ◽  
...  

Objectives.To evaluate individuals at high risk for tuberculosis exposure who had a history of a positive tuberculin skin test (TST) result in order to determine the prevalence of unsuspected negative TST results. To confirm these findings with the QuantiFERON-TB test (QFT), an in vitro whole-blood assay that measures tuberculin-induced secretion of interferon-γ.Methods.This survey was conducted from November 2001 through December 2003 at 3 sites where TST screening is regularly done. Detailed histories and reviews of medical records were performed. TSTs were placed and read by 2 experienced healthcare workers, and blood was drawn for QFT. Any subject with a negative result of an initial TST during the study (induration diameter, <10 mm) underwent a second TST and a second QFT. The TST-negative group comprised individuals for whom both TSTs had an induration diameter of <10 mm. The confirmed-negative group comprised individuals for whom both TSTs yielded no detectable induration and results of both QFTs were negative.Results.A total of 67 immunocompetent subjects with positive results of a previous TST were enrolled in the study. Of 56 subjects who completed the TST protocol, 25 (44.6%; 95% confidence interval [CI], 31.6%-57.6%) were TST negative (P<.001). Of 31 subjects who completed the TST protocol and the QFT protocol, 8 (25.8%; 95% CI, 10.4%-41.2%) were confirmed negative (P<.005).Conclusions.A significant proportion of subjects with positive results of a previous TST were TST negative in this study, and a subset of these were confirmed negative. These individuals' TST status may have reverted or may never have been positive. It will be important in future studies to determine whether such individuals lack immunity to tuberculosis and whether they should be considered for reentry into tuberculosis screening programs.


Sign in / Sign up

Export Citation Format

Share Document