Idiopathic anaphylaxis yardstick: Practical recommendations for clinical practice

Test Panel of Hidden Allergens for "Idiopathic Anaphylaxis" Reveals Wheat Allergy Dependent on Augmentation Factors as Common Final Diagnosis

BACKGROUND

Idiopathic anaphylaxis (IA) is an unresolved concern. Hidden allergens may be relevant in IA and in nonsteroidal anti-inflammatory drug hypersensitivity (NSAID-HS).

OBJECTIVE

To identify hidden elicitors for IA and NSAID-HS by a skin prick test (SPT) (13 allergens) and allergen-specific IgE (sIgE) panel (12 allergens) and to determine the value of each tested allergen.

METHODS

We retrospectively included all patients from 2018 to 2021 referred with a suspicion of IA or NSAID-HS by history in whom SPT and/or sIgE to allergens of the IA panel were performed. Patient characteristics from patients' records included comorbidities, history and symptoms of anaphylaxis, serum baseline tryptase level, total IgE level, SPT, sIgE, challenge results, and final diagnoses.

RESULTS

A total of 134 patients (77 female, mean age 39.7 ± 14.6 years) were included. Median serum baseline tryptase and total IgE levels were 4.23 μg/L and 133.5 kU/L, respectively. Allergologic workup with the IA panel resulted in positive SPT and sIgE in 61 (47%) and 66 (60%) patients, respectively. In those, confirmation or exclusion of allergy, mostly by challenge, led to a definitive diagnosis in 61 of 134 patients (46%). Skin prick test was most frequently positive to gluten (22.4%) and sIgE to ω5-gliadin (21.6%), which correlated with the history (r = 0.310, P < .001; and r = 0.407, P < .001, respectively). In 28 of 134 patients (21%) with initially suspected IA or NSAID-HS, challenges confirmed occult food allergy in which wheat allergy dependent on augmentation factors was the most frequent cause of anaphylaxis (19%).

CONCLUSIONS

Wheat allergy dependent on augmentation factors should be considered in all patients with anaphylaxis of unknown cause or after NSAID intake.

Approach to Idiopathic Anaphylaxis in Adolescents

Anaphylaxis is a potentially-life threatening condition. Adolescents are particularly vulnerable due to increased risk-taking behaviors, poor disease management, and minimized perception of risk. Although most anaphylaxis can be attributed to food, drug, or venom allergy via a detailed history and confirmatory studies, in nearly 1 in 5 cases, the cause may not be obvious. Clinical differentials including rare allergens, cofactors, mast-cell disorders, and mimic disorders can increase the likelihood of discovering of the cause of anaphylaxis.

Recent insights into the mechanisms of anaphylaxis

Anaphylaxis is an acute life-threatening systemic allergic reaction that can have a wide range of clinical manifestations. The most common triggers for anaphylaxis include food, medication, and venom. What is curious regarding anaphylaxis is how so many different agents can induce a severe systemic clinical response but only in a select subgroup of patients. Over the past decade, several important advances have been made in understanding the underlying cellular and molecular mechanisms contributing to anaphylaxis, with mast cells (MCs) being an essential component. Classically, cross-linked immunoglobulin E (IgE) bound to its high- affinity receptor induces MC mediator release. However, toll-like, complement, or Mas-related G-protein-coupled receptors also activate mouse and human MCs. While anaphylaxis secondary to foods historically has been more extensively characterized clinically and mechanistically, more recent studies have shifted focus toward understanding drug-induced anaphylaxis. The focus of this review is to highlight recent basic science developments and compare what is currently known regarding anaphylaxis to food, medications, and venom.

Mast Cell Activation Syndromes: Comparison Between Two Scoring Models to Predict for Mast Cell Clonality

BACKGROUND

The Red Española de Mastocitosis (Spanish Network on Mastocytosis) score (REMAs) and the National Institutes of Health idiopathic clonal anaphylaxis score (NICAS) were developed for more efficient screening of mast cell (MC) clonality in MC activation syndromes. In a limited idiopathic anaphylaxis case series, the NICAS showed higher accuracy compared with the REMAs.

OBJECTIVE

To compare the performance of the REMAs against the NICAS in the diagnosis of MC clonality.

METHODS

We compared the diagnostic value of the REMAs against the NICAS in 182 patients (63% men, median age 56 years) who presented with anaphylaxis triggered by Hymenoptera venom allergy (45%), drugs (15%), food (11%), idiopathic anaphylaxis (20%), and mixed causes (10%). KIT mutation was assessed in parallel in whole blood and bone marrow (BM) and, when negative, in highly purified BM MC. TPSAB1 was genotyped in a subset of 71 patients.

RESULTS

We found higher accuracy and rates of correctly classified patients for the REMAs (82% and 84%) compared with the NICAS (75% and 75%; P = .02 and P = .03, respectively), particularly among men (P = .05), patients with systemic mastocytosis (P = .05), those presenting anaphylaxis owing to any cause featuring urticaria (P = .04), cardiovascular symptoms (P = .02), and/or presyncope (P = .02) and those with a blood-negative/BM-positive KIT mutational profile (P = .002), but not hereditary α-tryptasemia-associated genotypes. Combined assessment of the REMAs and KIT^D816V in blood yielded an overall improved classification efficiency of 86% versus 84% for REMAs.

CONCLUSIONS

The combined use of the REMAs and blood detection of KIT^D816V is recommended, but more sensitive blood-based molecular assays to detect KIT^D816V are needed.

EAACI guidelines: Anaphylaxis (2021 update)

Anaphylaxis is a clinical emergency which all healthcare professionals need to be able to recognize and manage. The European Academy of Allergy and Clinical Immunology Anaphylaxis multidisciplinary Task Force has updated the 2014 guideline. The guideline was developed using the AGREE II framework and the GRADE approach. The evidence was systematically reviewed and recommendations were created by weighing up benefits and harms. The guideline was peer-reviewed by external experts and reviewed in a public consultation. The use of clinical criteria to identify anaphylaxis is suggested with blood sampling for the later measurement of tryptase. The prompt use of intramuscular adrenaline as first-line management is recommended with the availability of adrenaline autoinjectors to patients in the community. Pharmacokinetic data should be provided for adrenaline autoinjector devices. Structured, comprehensive training for people at risk of anaphylaxis is recommended. Simulation training and visual prompts for healthcare professionals are suggested to improve the management of anaphylaxis. It is suggested that school policies reflect anaphylaxis guidelines. The evidence for the management of anaphylaxis remains mostly at a very low level. There is an urgent need to prioritize clinical trials with the potential to improve the management of patients at risk of anaphylaxis.

Impact of mental health on disease activity in mastocytosis during COVID-19 pandemic

BACKGROUND

Mast cell-related symptoms might be influenced by mental health status in mastocytosis. In this study, we aimed to investigate the influence of mental health problems developed during the COVID-19 pandemic on the course of mastocytosis.

METHODS

Mental health status in 60 adult patients with mastocytosis was prospectively evaluated with the total Depression-Anxiety-Stress Scale (tDASS-21) and Fear of COVID-19 Scale (FCV-19S) in the lockdown period (LP) and the return to normal period (RTNP) during the pandemic. The disease course was assessed from emergency and outpatient medical reports, including Scoring Mastocytosis (SCORMA) index and serum baseline tryptase levels, by telephone interviews and clinical visits.

RESULTS

The mean FCV-19S and median tDASS-21 scores were significantly higher in LP than RTNP (p < 0.001) and there was a positive correlation between FCV-19S and tDASS-21 in LP (r = 0.820, p < 0.001) and in RTNP (r = 0.572 p= <0.001). Disease-related symptoms including skin lesions, flushing and anaphylaxis attacks increased in 22 patients in LP, and in this group, mean FCV-19S and median tDASS-21 were higher than those without symptom exacerbation (p < 0.001). During the study period, four (6.7%) patients who experienced COVID-19 recovered without any requirement for hospitalization and had not experienced symptom exacerbation.

CONCLUSIONS

Fear of COVID-19 can be a reason for mental health changes, including depression, anxiety and stress which may further increase mast cell-related symptoms. Therefore, psychological support is important to control the severity of mast cell-related symptoms in mastocytosis during a pandemic.

Idiopathic anaphylaxis: Diagnosis and management

Introduction: Idiopathic anaphylaxis (IA) is a diagnosis of exclusion and is based on the inability to identify a causal relationship between a trigger and an anaphylactic event, despite a detailed patient history and careful diagnostic assessment. The prevalence of IA among the subset of people who experienced anaphylaxis is challenging to estimate and varies widely, from 10 to 60%; most commonly noted is ∼20% in the adult anaphylactic population. Comorbid atopic conditions, such as food allergy, allergic rhinitis, and asthma, are present in up to 48% of patients with IA. Improved diagnostic technologies and an increased understanding of conditions that manifest with symptoms associated with anaphylaxis have improved the ability to determine a more accurate diagnosis for patients who may have been initially diagnosed with IA. Methods: Literature search was conducted on PubMed, Google Scholar and Embase. Results: Galactose-α-1,3-galactose (α-gal) allergy, mast cell disorders, and hereditary a-tryptasemia are a few differential diagnoses that should be considered in patients with IA. Unlike food allergy, when anaphylaxis occurs within minutes to 2 hours after allergen consumption, α-gal allergy is a 3-6-hour delayed immunoglobulin E-mediated anaphylactic reaction to a carbohydrate epitope found in red meat (e.g., beef, lamb, pork). The more recently described hereditary α-tryptasemia is an inherited autosomal dominant genetic trait caused by increased germline copies of tryptase human gene alpha-beta 1 (TPSAB1), which encodes α tryptase and is associated with elevated baseline serum tryptase. Acute management of IA consists of carrying an epinephrine autoinjector to be administered immediately at the first signs of anaphylaxis. Long-term management for IA with antihistamines and other agents aims to potentially reduce the frequency and severity of the anaphylactic reactions, although the evidence is limited. Biologics are potentially steroid-sparing for patients with IA; however, more research on IA therapies is needed. Conclusion: The lack of diagnostic criteria, finite treatment options, and intricacies of making a differential diagnosis make IA challenging for patients and clinicians to manage.

Idiopathic Anaphylaxis: A Diagnosis of Exclusion

We report the case of a 67-year-old female with hypertension and rheumatoid arthritis who had 5 unprovoked episodes of anaphylaxis in an 18-month period of time. We review idiopathic anaphylaxis, including its definition, diagnostic work-up, and differential diagnosis.

Use of omalizumab for management of idiopathic anaphylaxis: A systematic review and retrospective case series

BACKGROUND

Patients with idiopathic anaphylaxis (IA) may fail to respond to a combination of high-dose H₁ and H₂ antihistamines and mast cell stabilizers. Treatment options for these patients are currently limited.

OBJECTIVE

To describe the clinical experience of omalizumab use for the treatment of patients with IA with no evidence of underlying clonal mast cell disorders.

METHODS

We performed a retrospective review at 2 separate institutions of medical records of patients with a diagnosis of IA without evidence of mast cell clonality who had received treatment with omalizumab. We searched PubMed for studies describing omalizumab use in similar patients. Information on symptoms and omalizumab therapy was compiled, and response pattern of anaphylaxis was determined.

RESULTS

A total of 35 patients with IA and no evidence of mast cell clonality who received omalizumab were identified. The median age was 36 years at the start of omalizumab (range, 11-54 years; n = 29). The frequency of anaphylaxis episodes before omalizumab treatment varied from 2 total episodes to several episodes per month. The most often used initial omalizumab dose was 300 mg every 4 weeks (n = 16). Most patients ultimately achieved clinical response after starting omalizumab: complete response (63%, n = 22), partial response (28.5%, n = 10), with 3 nonresponders.

CONCLUSION

Omalizumab may be an effective treatment option for patients with IA who do not have evidence of mast cell clonality and fail to respond to antihistamines and mast cell stabilizers.

Hypersensitivity reactions and anaphylaxis to checkpoint inhibitor-monoclonal antibodies and desensitization

OBJECTIVE

To review type 1 hypersensitivity reactions and anaphylaxis to checkpoint inhibitor-monoclonal antibodies and its management with drug desensitization.

DATA SOURCES

English-language literature on MEDLINE regarding hypersensitivity, anaphylaxis, and checkpoint inhibitor-monoclonal antibodies.

STUDY SELECTIONS

References were selected based on relevance, novelty, robustness, and applicability.

RESULTS

There are well-known tissue toxicities associated to checkpoint inhibitors, but hypersensitivity reactions and anaphylaxis have been underreported. The presentation of these reactions is based on clinical phenotypes with underlying endotypes identified by specific biomarkers. Drug desensitizations have been successfully applied to checkpoint inhibitor drugs to allow patients with cancer to receive first-line therapies. This review provides current best practices for the recognition and diagnosis of hypersensitivity reactions and anaphylaxis to checkpoint inhibitors and their management using drug desensitization.

CONCLUSION

Hypersensitivity reactions and anaphylaxis have been identified as potential adverse effects induced by checkpoint inhibitor-monoclonal antibodies. Drug desensitization is a safe and effective treatment option for patients who experience hypersensitivity reactions in need of these monoclonal antibodies to improve cancer outcomes.

Critical Care Management of the Patient With Anaphylaxis: A Concise Definitive Review

OBJECTIVES

Anaphylaxis is a rapidly progressive life-threatening syndrome manifesting as pruritus, urticaria, angioedema, bronchospasm and shock. The goal of this synthetic review is to provide a practical, updated approach to the evaluation and management of this disorder and associated complications.

DATA SOURCES

A MEDLINE search was conducted with the MeSH of anaphylaxis, anaphylactic reaction, anaphylactic shock, refractory anaphylaxis and subheadings of diagnosis, classification, epidemiology, complications and pharmacology. The level of evidence supporting an intervention was evaluated based on the availability of randomized studies, expert opinion, case studies, reviews, practice parameters and other databases (including Cochrane).

STUDY SELECTION

Selected publications describing anaphylaxis, clinical trials, diagnosis, mechanisms, risk factors and management were retrieved (reviews, guidelines, clinical trials, case series) and their bibliographies were also reviewed to identify relevant publications.

DATA EXTRACTION

Data from the relevant publications were reviewed, summarized and the information synthesized.

DATA SYNTHESIS

This is a synthetic review and the data obtained from a literature review was utilized to describe current trends in the diagnosis and management of the patient with anaphylaxis with a special emphasis on newer evolving concepts of anaphylaxis endotypes and phenotypes, management of refractory anaphylaxis in the ICU setting and review of therapeutic options for the elderly patient, or the complicated patient with severe cardiorespiratory complications. Most of the recommendations come from practice parameters, case studies or expert opinions, with a dearth of randomized trials to support specific interventions.

CONCLUSION

Anaphylaxis is a rapidly progressive life-threatening disorder. The critical care physician needs to be familiar with the diagnosis, differential diagnosis, evaluation, and management of anaphylaxis. Skilled intervention in ICUs may be required for the patient with complicated, severe, or refractory anaphylaxis.

Idiopathic Anaphylaxis: a Perplexing Diagnostic Challenge for Allergists

PURPOSE OF REVIEW

The aim of this systematic review is to present the proposed theories of pathogenesis for idiopathic anaphylaxis (IA), to discuss its classification, its diagnostic approach, and management.

RECENT FINDINGS

IA represents a major diagnostic challenge and is diagnosed when excluding the possible identifiable triggers of anaphylaxis. The current research, however, revealed that certain conditions including mastocytosis, mast cell activation syndromes, and hereditary alpha tryptasemia can masquerade and overlap with its symptomatology. Also, newly identified galactose-alpha-1,3-galactose mammalian red meat allergy has recently been recognized as underlying cause of anaphylaxis in some cases that were previously considered as IA. IA comprises a heterogenous group of conditions where, in some cases, inherently dysfunctional mast cells play a role in pathogenesis. The standard trigger avoidance strategies are ineffective, and episodes are unpredictable. Therefore, prompt recognition and treatment as well as prophylaxis are critical. The patients should always carry an epinephrine autoinjector.

World allergy organization anaphylaxis guidance 2020

Anaphylaxis is the most severe clinical presentation of acute systemic allergic reactions. The occurrence of anaphylaxis has increased in recent years, and subsequently, there is a need to continue disseminating knowledge on the diagnosis and management, so every healthcare professional is prepared to deal with such emergencies. The rationale of this updated position document is the need to keep guidance aligned with the current state of the art of knowledge in anaphylaxis management. The World Allergy Organization (WAO) anaphylaxis guidelines were published in 2011, and the current guidance adopts their major indications, incorporating some novel changes. Intramuscular epinephrine (adrenaline) continues to be the first-line treatment for anaphylaxis. Nevertheless, its use remains suboptimal. After an anaphylaxis occurrence, patients should be referred to a specialist to assess the potential cause and to be educated on prevention of recurrences and self-management. The limited availability of epinephrine auto-injectors remains a major problem in many countries, as well as their affordability for some patients.

Clinical Manifestations and Causes of Anaphylaxis. Analysis of 382 Cases from the Anaphylaxis Registry in West Pomerania Province in Poland

Anaphylaxis is most commonly defined as an acute, severe, potentially life-threatening systemic hypersensitivity reaction. Current expert consensus has defined anaphylaxis as a serious reaction that is rapid in onset and can be fatal, and is a severe, potentially life-threatening systemic hypersensitivity reaction that is still rarely diagnosed. For safety reasons, patients should visit an allergologist to identify potential causes of this reaction. There are no data from other health care centres in Poland presenting characteristics of anaphylactic reactions. Clinical manifestations of anaphylaxis should be analysed, because some patients (10-30%) with anaphylaxis can present without cutaneous findings. This lack of skin/mucosa involvement can lead to misdiagnosis or delayed diagnosis of anaphylaxis. Objectives-to gather epidemiological data on anaphylactic reactions, to identify clinical manifestations of anaphylaxis (organ systems involved), to present diagnostic methods useful for the identification of anaphylaxis triggers, and most importantly, to find causes of anaphylaxis. In this retrospective analysis, we used a questionnaire-based survey regarding patients visiting the Clinical Allergology Department, Pomeranian Medical University (PMU) in Szczecin, between 2006 and 2015. The registry comprised patients with grade II (Ring and Messmer classification) or higher anaphylaxis. Patients with grade I anaphylaxis (e.g., urticaria) were not included in the registry. The incidence of anaphylaxis was higher in women. Clinical manifestations included cutaneous and cardiovascular symptoms, but more than 20% of patients did not present with cutaneous symptoms, which may create difficulties for fast and correct diagnosis. Causes of anaphylaxis were identified and confirmed by means of detailed medical interview, skin tests (STs), and measurement of specific immunoglobulin E (sIgE) and tryptase levels. In the analysed group, the most common cause of anaphylaxis (allergic and nonallergic) was Hymenoptera stinging (wasp), drugs (nonsteroidal anti-inflammatory drugs, NSAIDs) and foods (peanuts, tree nuts, celery). The incidence of anaphylaxis is low, but because of its nature and potentially life-threatening consequences it requires a detailed approach. Comprehensive management of patients who have had anaphylaxis can be complex, so partnerships between allergy specialists, emergency medicine and primary care providers are necessary. Monitoring its range is very important to monitor changes in allergy development.