Risk of Immediate-Type Allergy to Local Anesthetics Is Overestimated-Results from 5 Years of Provocation Testing in a Danish Allergy Clinic

Analysis of Allergy and Hypersensitivity Reactions to COVID-19 Vaccines According to the EudraVigilance Database

BACKGROUND

The coronavirus disease 2019 (COVID-19) pandemic presented a new challenge in modern medicine: the development of vaccines was followed by massive population vaccinations. A few reports on post-vaccination allergic reactions have made patients and medical personnel uneasy as to COVID-19 vaccines' allergic potential. Most of the studies in this area to date have been small, and some that were based on global databases skipped most of the allergic diseases and concentrated only on anaphylaxis. We aimed to analyze the incidence of serious allergic reactions based on the EudraVigilance (EV) database, regardless of the reported symptoms and allergy mechanism.

METHODS

The total number of administrated vaccine doses was extracted on 5 October 2023 from Vaccine Tracker and included all administrations since vaccinations began in the European Economic Area (EEA). Data on serious allergic reactions to COVID-19 vaccines were extracted from the EudraVigilance database with the same time point. The code names of 147 allergic symptoms or diseases were used.

RESULTS

The frequency of serious allergic reactions per 100,000 administered vaccine doses was 1.53 for Comirnaty, 2.16 for Spikevax, 88.6 for Vaxzevria, 2.11 for Janssen, 7.9 for Novavax, 13.3 for VidPrevtyn Beta, and 3.1 for Valneva. The most prevalent reported reactions were edema (0.46) and anaphylaxis (0.40). Only 6% of these reactions were delayed hypersensitivity-oriented.

CONCLUSIONS

The overall frequency of potential serious allergic reactions to COVID-19 is very rare. Therefore, COVID-19 vaccines seem to be safe for human use. The lowest frequency of allergic reaction was observed for Comirnaty and the highest for Vaxzevria.

EAACI/ENDA position paper on drug provocation testing

In drug hypersensitivity, drug provocation testing (DPT), also called drug challenge, is the gold standard for investigation. In recent years, risk stratification has become an important tool for adjusting the diagnostic strategy to the perceived risk, whilst still maintaining a high level of safety for the patient. Skin tests are recommended before DPT but may be omitted in low-risk patients. The task force suggests a strict definition of such low-risk patients in children and adults. Based on experience and evidence from studies of allergy to beta-lactam antibiotics, an algorithm on how to adjust DPT to the risk, and when to omit skin tests before DPT, is presented. For other antibiotics, non-steroidal anti-inflammatory drugs and other drugs, skin tests are poorly validated and DPT is frequently necessary. We recommend performing DPT with chemotherapeutics and biologicals to avoid unnecessary desensitization procedures and DPT with skin tests negative contrast media. We suggest DPT with anesthetics only in highly specialized centers. Specifics of DPT to proton pump inhibitors, anticonvulsants and corticosteroids are discussed. This position paper provides general recommendations and guidance on optimizing use of DPT, whilst balancing benefits with patient safety and optimizing the use of the limited available resources.

Local anesthetics allergy in children: Evaluation of diagnostic tests with Real-Life data

BACKGROUND

Local anesthetic (LA) drugs are commonly used in clinical practice to provide effective analgesia, including in dentistry and minor surgical procedures. The perception of a high risk of allergy in daily applications leads to the referral of atopic patients and those with other drug allergies to allergy clinics for the evaluation of allergic reactions to LA. The aim of this study was to determine who should be referred to the allergy clinic for LA allergy testing, assess the frequency of LA allergy in pediatric patients, and identify the negative predictive value of skin tests in diagnosis.

METHODS

January 2017-July 2023, the clinical and laboratory data, as well as the results of drug allergy tests, of patients referred to our pediatric allergy clinic by dentists and physicians performing minor surgical procedures with suspected LA allergy were retrospectively evaluated.

RESULTS

Our study included a total of 153 patients, comprising 84 girls (54.9%) and 69 boys (45.1%), with a mean age of 8.9 (±3.3) years. The most common reason for referral was a history of non-LA drug allergies (n = 66, 43.2%), followed by asthma (n = 25, 16.3%). Hypersensitivity reactions (HRs) with LA were most commonly associated with articaine (n = 7, 4.8%), followed by lidocaine (n = 6, 4.1%). When intradermal tests were evaluated, 17 patients (11.1%) had a positive test result. The positivity for lidocaine was 70.6% (n = 12), and prilocaine was 29.4% (n = 5). Subcutaneous provocation was administered to 109 patients (71.2%), and one patient exhibited local erythema and swelling with prilocaine.

CONCLUSION

Although LA allergy is a rare occurrence, consultations of this nature are frequently requested from allergy clinics in real life. Considering the negative predictive value of skin tests performed with LA drugs, the reaction rate appears to be low in patients with atopy or other drug allergies. It is crucial for all relevant healthcare professionals to be knowledgeable about the appropriate approach to suspected LA allergies to avoid unnecessary tests. To the best of our knowledge, our study is the most comprehensive work in the literature that evaluates the results of diagnostic tests in children referred with a suspicion of LA allergy.

Allergy to Local Anesthetics is a Rarity: Review of Diagnostics and Strategies for Clinical Management

Local anesthetics (LA) are commonly used in procedures and in topical agents for pain management. With the increasing use of LA drugs, the management of LA reactions is more frequently encountered in the office and in operating rooms. True allergic reactions involving IgE-mediated reactions and anaphylaxis are rare; they have only been identified in case reports and account for less than 1% of adverse LA reactions. Most reactions are non-allergic or are a result of hypersensitivity to other culprits such as preservatives, excipients, or other exposures. LA reactions that are misclassified as true allergies can lead to unnecessary avoidance of LA drugs or delays in surgical procedures that require their use. A detailed history of prior LA reactions is the first and most crucial step for understanding the nature of the reaction. Reactions that are suspicious for an immediate hypersensitivity reaction can be evaluated with skin prick and intradermal testing with subsequent graded challenge. Reactions that are suspicious for a delayed hypersensitivity reaction can be evaluated with patch testing.

Urticaria After Lidocaine Use for Pecto-Intercostal Nerve Block

Urticaria within one hour of lidocaine injection is a sign of type I (immediate) hypersensitivity to lidocaine, yet most patients suspected of having a lidocaine allergy do not exhibit urticaria. Aside from being a sign of a rare lidocaine allergy, urticaria can also be a symptom of COVID-19. COVID-19 patients who experience urticaria after receiving lidocaine require careful evaluation to determine the cause. Here, we present a case of a patient exhibiting urticaria one hour after a lidocaine injection for the Pecto-intercostal nerve block to treat COVID-19-induced costochondritis.

Local Anesthesia in Interventional Radiology

Interventional radiology is an evolving field that treats a variety of diseases. Local anesthetics is an important component of pain management during interventional radiologic procedures. It is highly effective and generally safe for routine procedures. However, local anesthetics can be associated with painful initial injection, allergic reactions, and rare but potentially devastating systemic toxicities. Recent evidence has shown that buffered solution and warm local anesthetics may reduce injection discomfort and improve clinical efficacy. Sensible safety practices and prompt recognition/treatment of the systemic toxicity are of paramount importance to provide safe local anesthesia. Interventional radiologists should be familiar with the basic pharmacology, common local anesthetics, optimizing strategies, complications, and management to provide safe and effective local anesthesia for patients.

Risk Factors for Immediate-Type Local Anesthetic Hypersensitivity Reactions in Pediatric Patients: A Retrospective Case-Control Study

Background

Local anesthetics (LA) are relatively safe and rarely cause immediate hypersensitivity reactions. The data on immediate LA hypersensitivity and its risk factors in children are limited.

Aim

To evaluate risk factors of immediate LA hypersensitivity.

Methods

The retrospective case-controlled study included 17 patients with confirmed immediate LA hypersensitivity. For each patient, three age- and gender-matched control subjects were included in the study. LA hypersensitivity was excluded by skin tests and subcutaneous drug provocation tests in all control subjects.

Results

The most common allergic assessment in the patient/control group was for lidocaine (n=5; 29.4%, vs n=23; 45.1%). Suspected LA hypersensitivity reactions were found to be associated with cutaneous manifestations in 14 (82.4%) patients and in 7 (13.7%) of the controls. A history of exposure to local anesthetics twice or more was present in 11 (64.7%) patients vs 6 (11.8%) controls. In conditional regression analysis, repeated LA exposure (≥2) and cutaneous findings were determined as significant risk factors (Odds Ratio [OR]:5.7; 95% Confidence Interval [CI]:1.2–27.1; P=0.029 and (OR:17.3; 95% CI:3.6–82.5; P<0.001, respectively).

Conclusion

Cutaneous manifestations and a history of LA exposure twice or more were predictive factors for LA allergy confirmed by skin test in children.

Investigation of perioperative hypersensitivity reactions: an update

PURPOSE OF REVIEW

The purpose of this review is to provide an update on how best to manage the investigation of suspected perioperative hypersensitivity reactions based on recent literature and key publications.

RECENT FINDINGS

In the past two years, several very important initiatives have been taken in the field of perioperative hypersensitivity. The 6th national audit project in the United Kingdom has provided new knowledge through a series of studies, including a nationwide prospective study, and the European Academy of Allergy and Clinical Immunology has commissioned a position paper with updated recommendations for investigations. Lastly, a large international working group comprising experts in anesthesiology, allergology, and immunology, the International Suspected Perioperative Allergic Reactions group, has published a series of articles providing updates and new insights into several different key areas of perioperative hypersensitivity.

SUMMARY

The investigation of perioperative hypersensitivity reactions is highly complex and aims to identify the correct culprit to ensure future avoidance but also to disprove allergy to other suspected culprits, making them available for subsequent anesthesia. To achieve this, close collaboration between anesthesiologists and allergists is called upon to ensure the best possible outcome for the patient.

Perioperative Anaphylaxis: Evaluation and Management

Perioperative anaphylaxis (PA) is a rare but life-threatening condition that poses diagnostic and management challenges in the operating room. The incidence of severe perioperative reactions is estimated to be approximately 1:7000-10,000. Management involves both immediate stabilization of the patient and identifying the culprit agent. Identification is essential to prevent recurrence of the event in subsequent surgeries and to avoid unnecessary labeling of drug allergy. Identifying all possible exposures including medications, disinfectants, latex, and dyes and choosing the appropriate tests are essential for proper evaluation. To identify the culprit, primary testing modalities include tryptase at the time of the reaction with subsequent levels and skin testing with nonirritating concentrations to the medications and substances utilized during the procedure and those potentially used as alternates. This strategy provides guidance for future surgeries and procedures. Close collaboration between the allergy, anesthesiology, and surgery teams is essential for appropriate management of these patients at the time of the reaction, during the post event evaluation and in preparation for subsequent surgeries.

Identification of Risk Factors and Cross-Reactivity of Local Anesthetics Hypersensitivity: Analysis of 14-Years' Experience

Purpose

Local anesthetics (LA) are widely used and adverse drug reactions (ADR) occur in 2.5–10%, but hypersensitivity reactions are rare (ranging between 0% and 4.3%). Risk is so overestimated causing too many allergy clinic referrals. There are limited and also conflicting results over the management of LA allergy. We aimed to find out who should be referred to an allergy clinic for a LA allergy testing, to define the subjects with an increased risk of LA allergy and to assess the need for testing for identifying alternative LA.

Patients and Methods

We performed a retrospective study of patients referred to our clinic for diagnostic workup of LA hypersensitivity from 2006 to 2020.

Results

In our cohort of 398 patients, tests were positive in 14 (3.52%) of them. Personal history of ADR with LA was the only independent risk factor for positive test (RR=4.007, p=0.033). Presence of generalized cutaneous symptoms and hypotension during past reaction were independent predictors of positive test (RR=9.043, p=0.021 and RR=10.445, p=0.038, respectively). The negative predictive value of intradermal test at dilution of 1:100 for immediate-type reaction was high (97.56%). Also, we demonstrated cross-reactivity within the amide-group LAs and co-occurrence of immediate- and delayed-type reactions.

Conclusion

Only patients with an LA-induced ADR should be referred to an allergy clinic. History of generalized cutaneous symptoms and/or hypotension during the reaction may define subjects with an increased risk of LA allergy. A stepwise test procedure may start with skin tests especially for these patients with increased risk factors. In presence of LA allergy, alternative LA should always be confirmed by performing a challenge test.

Risk of True Allergy to Local Anesthetics: 10-Year Experience from an Anesthesia Allergy Clinic in China

Background

Local anesthetics (LAs) have been widely used throughout the healthcare settings, especially in local anesthesia and pain management. The incidence of allergic reactions to LAs remains uncertain. The danger of allergic reactions to the use of LAs in every day of clinical practice is a matter of great concern. Therefore, it is necessary to investigate the risk of true allergy to LAs.

Methods

This study retrospectively evaluated the medical records of patients who were referred to an anesthesia allergy clinic in China and underwent allergy tests with LAs over a 10-year period from 2009 to 2019. The following information was collected from medical records: demographics of the patients, reasons for referral, clinical features of drug hypersensitivity reaction (DHR), and test results with LAs. Skin tests combined with an in vitro method, basophil activation test (BAT), were used to investigate allergic reactions to LAs.

Results

A group of 109 patients were included in the analysis. The main reason for referral was the presence of a suspected DHR after procedures with LAs (n=68, 62%), the second most common reason for referral was a history of DHR to other drugs and the need to use LAs for upcoming procedures (n=41, 38%). Of the 68 patients with a suspected DHR to LAs, only six cases presented true allergy and showed positive results in skin tests and/or BAT. And all 41 patients who had a history of DHR to other drugs presented negative in all tests.

Conclusion

Risk of true allergy to LAs may be very low. However, patients with a suspected history of DHR to LAs should be considered for allergy tests. Skin tests and BAT may be useful in the investigation and diagnosis of true allergy to LAs in clinical practice.

[Update on perioperative hypersensitivity reactions: joint document from the Brazilian Society of Anesthesiology (SBA) and Brazilian Association of Allergy and Immunology (ASBAI) - Part II: etiology and diagnosis]

This second joint document, written by experts from the Brazilian Association of Allergy and Immunology (ASBAI) and Brazilian Society of Anesthesiology (SBA) concerned with perioperative anaphylaxis, aims to review the pathophysiological reaction mechanisms, triggering agents (in adults and children), and the approach for diagnosis during and after an episode of anaphylaxis. As anaphylaxis assessment is extensive, the identification of medications, antiseptics and other substances used at each setting, the comprehensive data documentation, and the use of standardized nomenclature are key points for obtaining more consistent epidemiological information on perioperative anaphylaxis.

Update on perioperative hypersensitivity reactions: joint document from the Brazilian Society of Anesthesiology (SBA) and Brazilian Association of Allergy and Immunology (ASBAI) - Part II: etiology and diagnosis

This second joint document, written by experts from the Brazilian Association of Allergy and Immunology (ASBAI) and Brazilian Society of Anesthesiology (SBA) concerned with perioperative anaphylaxis, aims to review the pathophysiological reaction mechanisms, triggering agents (in adults and children), and the approach for diagnosis during and after an episode of anaphylaxis. As anaphylaxis assessment is extensive, the identification of medications, antiseptics and other substances used at each setting, the comprehensive data documentation, and the use of standardized nomenclature are key points for obtaining more consistent epidemiological information on perioperative anaphylaxis.

Epidemiology and drug allergy results in children investigated in allergy unit of a tertiary-care paediatric hospital setting

Background and objective

Drug Hypersensitivity Reactions (DHRs) are considered adverse effects of medications that resemble allergy symptoms. The reported positive clinical history of pediatric drug reactions is about 10%, however, after allergy investigations, only a small percent is confirmed as hypersensitivity.

The aim of this study was to analyze the clinical history, allergy work-up results and sensitization profile of children and adolescents referred to our Allergy Unit for suspected DHRs.

Methods

The study evaluated data related to a group of children with a positive history of drug reactions during a two-year period. The allergy work-up consisted of in vivo and in vitro tests, in accordance with the recommendations of the ENDA/EAACI guidelines.

Results

Data from a group of 637 patients [348 M (54.6%); 289 F (45.4%)] were retrospectively analyzed. Beta lactams (BLs) were the most common drugs involved in the reported clinical history, followed by non-steroidal anti-inflammatory drugs (NSAIDs). Severe cutaneous adverse reactions (SCARs) were most frequently observed during BL treatment. The confirmation of BL hypersensitivity was higher for immediate reactions (IRs) [9.4%; 5.1% through positive skin tests (STs) and 5.5% through drug provocation test (DPT)] compared to non-immediate reactions (non-IRs) (8.1%; 2.2% through STs and 6.2% through DPT). A higher number of positive results was obtained for BLs and macrolides when the tests were performed within 12 months after the index reaction (p < 0.05). During DPTs with amoxicillin-clavulanic acid, four hypersensitivity reactions (including one anaphylaxis) occurred despite negative STs.

Conclusion

Our data demonstrated that only 9.1% of patients resulted in being positive to allergy tests which is in line with the data in literature. An allergy work-up is mandatory for excluding suspected hypersensitivity.

Safety of local anesthetics

Local anesthetics are essential medications for the conduction of dermatological procedures. They stop the depolarization of nerve fibers and are divided into two main categories, the amide and ester types. Systemic toxicity with reflex on the central nervous and cardiovascular systems is their most feared adverse reactions, and the anaphylactic reaction is the most concerning one. Although potentially fatal, these events are extremely rare, so local anesthetics are considered safe for use in in-office procedures.

Recent developments and highlights in drug hypersensitivity

Drug hypersensitivity reactions (DHRs) are nowadays the third cause of allergy after rhinitis and asthma with a significant increase in prevalence in both adults and paediatric population with new drugs included as culprit. For this, DHRs represent not only a health problem but also a significant financial burden for affected individuals and health systems. Mislabelling DHRs is showing to be a relevant problem for both, false label of drug allergic and false label of nonallergic. All this reinforces the need to improve accurate diagnostic approaches that allow an appropriate management. Moreover, there is a need for training both, nonallergist stakeholders and patients to improve the reaction identification and therefore decrease the mislabelling. The use of allergy cards has shown to be relevant to avoid the induction of DHRs due to the prescription of wrong medication. Recent developments over the last 2 years and highlights about risk factors, diagnostic approaches, mechanisms involved as well as prevention actions, and management have been reviewed. In these papers, it has been outlined the need for correct diagnosis and de-labelling of patients previously false-reported as allergic, which will improve the management and treatment of patients with DHRs.

An EAACI position paper on the investigation of perioperative immediate hypersensitivity reactions

Perioperative immediate hypersensitivity reactions are rare. Subsequent allergy investigation is complicated by multiple simultaneous drug exposures, the use of drugs with potent effects and the many differential diagnoses to hypersensitivity in the perioperative setting. The approach to the investigation of these complex reactions is not standardized, and it is becoming increasingly apparent that collaboration between experts in the field of allergy/immunology/dermatology and anaesthesiology is needed to provide the best possible care for these patients. The EAACI task force behind this position paper has therefore combined the expertise of allergists, immunologists and anaesthesiologists. The aims of this position paper were to provide recommendations for the investigation of immediate-type perioperative hypersensitivity reactions and to provide practical information that can assist clinicians in planning and carrying out investigations.

Lidocaine as a Rare and Hidden Allergen in the Perioperative Setting: A Case Report

Local anesthetics are used throughout the health care system. In the perioperative setting and in other settings of exposure to local anesthetics, true allergy is reported very rarely. We present an unusual case of immediate-type perioperative hypersensitivity to lidocaine with cross-reaction to mepivacaine, which was missed on initial investigation. This case illustrates that lidocaine may be a "hidden allergen" in the perioperative setting and should always be considered a potential culprit in cases of suspected perioperative hypersensitivity. The case also demonstrates that suspected perioperative hypersensitivity requires highly specialized investigation and close collaboration between allergists and anesthesiologists.

Comparative epidemiology of suspected perioperative hypersensitivity reactions

Suspected perioperative hypersensitivity reactions are rare but contribute significantly to the morbidity and mortality of surgical procedures. Recent publications have highlighted the differences between countries concerning the respective risk of different drugs, and changes in patterns of causal agents and the emergence of new allergens. This review summarises recent information on the epidemiology of perioperative hypersensitivity reactions, with specific consideration of differences between geographic areas for the most frequently involved offending agents.

Differential diagnosis of late-type reactions to injected local anaesthetics: Inflammation at the injection site is the only indicator of allergic hypersensitivity

BACKGROUND

Anaphylaxis-like reactions developing within a few minutes are the most frequent complications of subcutaneous or submucosal injections of local anaesthetics (LAs), and topically applied LAs are potential contact allergens. In addition, injected LAs have been reported to induce delayed reactions, including local inflammation at the injection site, and various general symptoms.

OBJECTIVES

To assess the frequency and symptoms of late-type hypersensitivity occurring several hours after LA injections.

METHODS

We retrospectively evaluated clinical data and test results from all patients referred to our allergy clinic in a period of 20 years for diagnostic work-up of LA-associated late-type reactions.

RESULTS

Of 202 patients reporting symptoms with onset at least 1 hour after LA injection, 40 had cutaneous inflammation confined to the injection site, and 162 reported various systemic symptoms. LA hypersensitivity could be excluded in all patients with systemic complaints by means of skin testing and subsequent subcutaneous provocation. In 8 of the 40 patients (20%) with local inflammatory reactions, late-type allergic LA hypersensitivity was confirmed.

CONCLUSIONS

Late-type LA allergy commonly causes inflammatory skin reactions confined to the injection site. Conversely, LAs are highly unlikely to trigger delayed systemic symptoms such as urticarial or exanthematous skin eruptions.

The Journal of Allergy and Clinical Immunology: In Practice 2018 Highlights

A large number of clinically impactful studies and reviews were published in this journal in 2018. This article provides highlights of the original research published in 2018 issues of The Journal of Allergy and Clinical Immunolgy: In Practice on the subjects of anaphylaxis, asthma, dermatitis, drug allergy, eosinophilic disorders, food allergy, immune deficiency, rhinitis, and urticaria/angioedema and mast cell disorders. Within each topic, practical aspects of diagnosis and management are emphasized. Treatments discussed include lifestyle modifications, allergen avoidance therapy, positive and negative effects of pharmacologic therapy, and various forms of immunologic and desensitization management. We hope this review will help readers consolidate and use this extensive and practical knowledge for the benefit of patients.