Medical Journal Review
WAO Reviews - Editors' Choice
The Editors select articles for their importance to clinicians who care for patients with asthma and allergic/immunologic diseases, and whenever possible they seek articles that everyone can access freely. The Editors’ Choice comes to you from Juan Carlos Ivancevich, MD, WAO Web Managing Editor, and summary author, John J. Oppenheimer, MD, FACAAI, FAAAAI, WAO Reviews Editor.
Maternal allergen-specific IgG may protect the child against allergic sensitization
Lupinek C, Hochwallner H, Johansson C et al.
Journal of Allergy and Clinical Immunology 2019; Published online ahead of print (24 January). pii: S0091-6749(19)30106-X. DOI: https://doi.org/10.1016/j.jaci.2018.11.051
It has long been postulated that specific IgG to food may play a role in food tolerance. The objective of this study was to analyze IgG reactivity to micro-arrayed allergens in mothers during pregnancy, and in children through early childhood. To do so, the authors examined samples from mothers during the third trimester, cord blood, breast milk collected at 2 months after delivery, and plasma samples from children at 6, 12 and 60 months of age to IgG reactivity to 164 micro-arrayed allergens (ImmunoCAP ISAC technology) in the Swedish birth cohort ALADDIN. Also, IgE sensitizations to micro-arrayed allergens were assessed at 5 years of age in these children.
They found that allergen-specific IgG reactivity profiles in mothers, cord blood and breast milk were highly correlated. Maternal allergen-specific IgG persisted in some children at 6 months. Children´s allergen-specific IgG production occurred at 6 months and reflected allergen exposure. Interestingly, children who were IgE-sensitized against an allergen at 5 years of age had significantly higher allergen-specific IgG levels than non-sensitized children. On the other hand, in all 164 tested allergens, children from mothers with elevated (>30 ISU) specific plasma IgG against an allergen had no IgE sensitizations against that allergen at 5 years of age. Overall, this indicates that high maternal allergen-specific IgG levels during pregnancy protect against allergic sensitization in the offspring, which may open new avenues for the prevention of allergic diseases.
Factors associated with exacerbations among adults with asthma according to electronic health record data
Greenblatt RE, Zhao EJ, Henrickson SE et al.
Asthma Research and Practice 2019; 5:1. DOI: https://doi.org/10.1186/s40733-019-0048-y
Electronic health records (EHRs) are a unique source of information, providing a great opportunity to understand factors associated with asthma in real-life populations. In this study, the authors identified demographic factors and comorbidities associated with asthma exacerbations among adults derived from EHR data and compare these findings to those of epidemiological studies. To do so, they explored University of Pennsylvania Hospital System EHR-derived data for asthma encounters occurring between 2011 and 2014. Regression analyses were performed to model asthma exacerbation frequency as explained by age, sex, race/ethnicity, health insurance type, smoking status, and body mass index (BMI), as well as other comorbidities, and compared these findings to data from the National Health and Nutrition Examination Survey (NHANES) from 2001 to 2012. In their cohort of over 9,000 patients with asthma, 33.37% had at least one exacerbation over the four-year study period.
They found that the comorbid factors of chronic bronchitis, sinusitis, emphysema, fluid and electrolyte disorders, class 3 obesity, and diabetes were strongly associated with exacerbations among adults with asthma. When comparing these results to epidemiologic studies, COPD, obesity and sinusitis were the most generalizable factors across EHR-based as well as epidemiological study populations. Lastly in the EHR population specifically, race and health insurance type were strongly associated with exacerbations among those patients who had 5+ exacerbations, as well as those with less preventive care. This study highlights that EHR-derived data are helpful to understand the characteristics of real-life people with asthma.
Vilnius Declaration on chronic respiratory diseases: Multisectoral care pathways embedding guided self-management, mHealth and air pollution in chronic respiratory diseases
Valiulis A, Bousquet J, Veryga A et al.
Clinical and Translational Allergy 2019; 9:7. DOI: https://doi.org/10.1186/s13601-019-0242-2
With over 1 billion people suffering from chronic respiratory illness, and a significant proportion of this group having uncontrolled illness with its downstream enormous cost to society, a meeting was held in Vilnius, Lithuania (March23, 2018) under the auspices of the Ministry of Health and several scientific societies to propose multisectoral care pathways embedding guided self-management, mHealth and air pollution in selected chronic respiratory diseases (rhinitis, chronic rhinosinusitis, asthma and COPD). As a result of this meeting, the Vilnius Declaration was developed by the participants. In this paper, the authors review the Vilnius Declaration, which represents an important step in the fight against air pollution in chronic respiratory diseases globally. This “Declaration” has a clear strategic relevance with regard to the European Union Health Strategy and should bring added value to the existing public health knowledge.
Anaphylaxis to intravenous gelatin-based solutions: A case series examining clinical features and severity
Farooque S, Kenny M, Marshall SD
Anaesthesia 2019; 74(2): 174-179. DOI: https://doi.org/10.1111/anae.14497
Due to safety concerns regarding starch-based volume expanders, there has been an increase in use of gelatin-based colloids. Unfortunately, research suggests hypersensitivity reactions to intravenous gelatin-based solutions occur at similar rates per administration as non-depolarising neuromuscular blocking agents such as rocuronium (6.2/100,000 administrations). To better understand this issue, the authors evaluated cases from their own large drug allergy clinic. They retrospectively reviewed clinical histories, skin test results and severity of reactions in this cohort of patients with gelatin associated reactions. Twelve patients with anaphylaxis to gelatin-based solutions were identified (8 women, mean [SD] age 58  years). Eleven reactions were severe or life threatening with 3 progressing to cardiac arrest. Presentation was commonly delayed, with only 3 patients developing reactions within 5 minutes of the solution administered, with a further six presenting 10–70 minutes later. When measured, tryptase was elevated in all patients (median (IQR [range]) 14.7 (8.2–23.8 [6.5–83.4]) ng.ml-1). Overall, this demonstrates that reactions to gelatin-based solutions are usually severe and can present with latency uncommon with other intravenous anaesthetic triggers. The authors conclude by suggesting that the use of gelatin-based solutions in the peri-operative setting should be reassessed given the risk of severe allergy.
Precision medicine allergy immunoassay methods for assessing immunoglobulin E sensitization to aeroallergen molecules
Popescu FD, Vieru M
World Journal of Methodology 2018; 8(3): 17-36. DOI: 10.5662/wjm.v8.i3.17
This is an excellent review of the use of allergy immunoassay methods for assessing immunoglobulin E (IgE) sensitization to aeroallergens. Molecular-based allergy diagnosis for the in vitro assessment of an IgE sensitization profile at the molecular level uses allergen molecules/allergen components, which are well-defined, highly purified, natural allergen components or recombinant allergens. Modern immunoassay methods used for the detection of specific IgE against aeroallergen components are either singleplex (such as the fluorescence enzyme immunoassay with capsulated cellulose polymer solid-phase coupled allergens, the enzyme-enhanced chemiluminescence immunoassay and the reversed enzyme allergosorbent test, with liquid-phase allergens), multiparameter (such as the line blot immunoassay for defined partial allergen diagnostics with allergen components coating membrane strips) or multiplex (such as the microarray based immunoassay on immuno solid-phase allergen chip, and the two new multiplex nanotechnology-based immunoassays: the patient-friendly allergen nanobead array, and the macroarray nanotechnology-based immunoassay used as a molecular allergy explorer).
The authors stress that comprehensive and accurate IgE sensitization molecular profiling, with identification of the relevant allergens, is indicated within the framework of a patient clinical history, to distinguish “genuine” IgE sensitization from sensitization due to cross-reactivity (especially in polysensitized patients), to assess unclear symptoms and unsatisfactory response to treatment, to reveal unexpected sensitizations, and to improve assessment of severity and risk aspects in patients. In the end, component-resolved diagnosis of the specific IgE repertoire has a key impact on optimal decision making for prophylactic and specific immunotherapeutic strategies tailored for an individual patient.