Hypersensitivity to local anaesthetics

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.

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

BACKGROUND

Local anesthetics (LAs) are used in many health care settings and exposure during a lifetime is almost inevitable. Immediate-type allergy to LAs is considered rare among allergy experts but is commonly suspected by health care workers from other specialties, and by patients.

OBJECTIVE

The main aim of this study was to investigate the incidence of immediate-type allergy to LAs in our regional allergy clinic over the 5-year period 2010 to 2014.

METHODS

This was a retrospective single-center study of patients referred to a regional allergy clinic (excluding patients with perioperative reactions) with suspected immediate allergy to LAs, who had undergone subcutaneous provocation with 1 or more LAs. Patients were identified in the hospital clinical coding system and clinical information about the reaction and investigation results was obtained from their medical records.

RESULTS

A total of 164 patients (123 women/41 men; median age, 56 years; range, 7-89 years) who had 189 provocations with LAs were included over the 5-year period 2010 to 2014. All 164 patients had negative subcutaneous provocations to all 189 tests with LAs (95% CI, 0%-1.83%). Another allergen was identified in 10% (n = 17) of the patients.

CONCLUSIONS

None of the 164 patients with suspected immediate-type allergy to LAs reacted on provocation. Thus, no patients have been diagnosed with an immediate allergy to LAs in our regional allergy clinic in the 5-year period studied, and allergy to LAs must be considered very rare. Alternative mechanisms should be considered, but if symptoms are consistent with allergy, other potential allergens should be investigated.

No cases of perioperative allergy to local anaesthetics in the Danish Anaesthesia Allergy Centre

BACKGROUND

Local anaesthetics (LA) are often suspected as possible causes of allergic reactions. The Danish Anaesthesia Allergy Centre (DAAC) is the national reference centre for investigation of perioperative allergic reactions. The purpose of this study was to investigate the incidence of IgE-mediated immediate type perioperative allergic reactions to LA.

METHODS

In the period 2004-2013, a total of 409 patients (244 women/165 men; median age 49 years, range 1-86 years) were investigated in DAAC on suspicion of allergy associated with anaesthesia and surgery. A total of 162 (40%) patients were exposed to one or more LA. Suspected allergy to LA was investigated by prick test, intradermal test and subcutaneous provocation with the suspected drug. Patients with positive skin tests still underwent subcutaneous provocation, as false positive skin tests can occur.

RESULTS

A total of 203 test series with LA were carried out on 162 patients (89 women/73 men; mean age 49 years, range 2-85 years) with the following drugs: Lidocaine n = 80 (49%), bupivacaine n = 82 (51%), ropivacaine n = 31 (19%) and mepivacaine n = 10 (6%). All 162 patients had negative subcutaneous provocation for all tested LA (95% CI: 0-1.8%). Investigations revealed another allergen in 52 of 162 patients.

CONCLUSION

None of the 162 patients with suspected perioperative allergic reactions and exposure to LA reacted on subcutaneous provocation with the relevant LA. Thus, no patients have been diagnosed with allergy to LA in DAAC in the period 2004-2013 and allergy to LA must be considered very rare in this population.

Identifying and Managing Local Anesthetic Allergy in Dermatologic Surgery

BACKGROUND

Local anesthetic (LA) allergy is a concern for dermatologic surgeons given the large number of procedures performed yearly with LAs. Many patients also have anxiety about past or potential anesthesia allergy.

OBJECTIVE

This article will review the symptoms of IgE-mediated allergic reactions, the prevalence of IgE-mediated LA allergy, discuss common mimics of LA, and propose a practical approach for diagnostic and therapeutic options for LA allergy for the dermatologic surgeon in practice.

MATERIALS AND METHODS

A literature search of Pubmed using keywords "lidocaine," "local anesthetic," "hypersensitivity," and "allergy" was performed.

RESULTS

Amide anesthetics result in the most reports of true local anesthetic immediate hypersensitivity.

CONCLUSION

True IgE-mediated anaphylaxis to local anesthesia is very rare. Dermatologic surgeons should be aware of the symptoms of anesthetic allergy and its mimickers, as well as how to manage allergic reactions in their clinical practice.

Allergy to lidocaine injections: comparison of patient history with skin testing in five patients

INTRODUCTION

True allergy to local anesthetics, especially lidocaine, is uncommon. Most adverse reactions to this group of medications are classified as psychomotor, autonomic or toxic. In the case of suspected hypersensitivity to local anesthetics, skin testing is considered to be a useful tool - patch tests and intradermal tests for delayed hypersensitivity and skin prick tests and intradermal tests for immediate reactions. There is a particular need for such a diagnostic procedure, as patients suspected of hypersensitivity to local anesthetic drugs are frequently admitted.

AIM

To highlight the problem of hypersensitivity to local anesthetics on the basis of authors' own experience and literature data.

MATERIAL AND METHODS

We present cases of 5 patients referred to the clinic by their dentists with a suspicion of allergy to local anesthetics, four to lidocaine and 1 to articaine.

RESULTS

Intradermal tests were positive in 1 out of 5 subjects, with a concomitant episode of urticaria. In 1 patient we obtained a doubtful result of intradermal tests. Skin prick tests and patch tests were negative in all cases. In 2 cases we performed an incremental challenge test also with a negative result.

CONCLUSIONS

It has to be emphasized that, although rare, consequences of true allergy to local anesthetics can be serious considering a patient's future management and therapy. That is why this diagnosis may be crucial.

The negative predictive value of typing safe local anesthetics

BACKGROUND

Although allergy to local anesthetics (LA) is rare, patients often report unwanted reactions after their administration. A history of anaphylaxis or an atypical reaction related to LA is an indication for typing a safe anesthetic for future surgical or dental procedures.

AIM

The aim of the study was to determine the negative predictive value (NPV) of typing safe LA.

METHODS

A total of 154 patients with a history of an unwanted reaction to LA were enrolled into the study. Stepwise typing of a safe anesthetic included skin prick tests (SPT) and intracutaneous tests (ICT) with two or three of the following LA: lidocaine, bupivacaine, mepivacaine, and articaine. Skin tests were followed by provocations with one or two LA. Telephone follow-up visits were performed 4-12 months after drug typing. On the basis of follow-up questionnaire results, the NPV of the protocol was calculated.

RESULTS

The full protocol was performed in 148 patients. Positive results of SPT were observed in 2, of ICT in 19 and of provocations in 11 cases. Lidocaine was found safe in 44, bupivacaine in 14, mepivacaine in 34 and articaine in 61 patients. The drug typed at the clinical visit was administered in 78 patients, and 76 reported no reactions (NPV = 97%).

CONCLUSION

Stepwise approach including SPT, ICT and provocations is safe and allows typing a safe anesthetic in a vast majority of patients.

IgE-mediated allergy to local anaesthetics: separating fact from perception: a UK perspective

Local anaesthetic (LA) agents have been routinely used in dentistry, ophthalmology, minor surgery, and obstetrics since the late nineteenth century. Reports relating to adverse reactions and LA allergy have appeared in the published literature for several years. However, the incidence of true, IgE-mediated LA allergy remains uncertain and is presumed to be very low. We critically reviewed the English language literature on suspected LA allergy and its investigation with the aim of estimating the reported prevalence and analysing the role of different tests currently used to identify and confirm LA allergy. Twenty-three case series involving 2978 patients were identified and analysed. Twenty-nine of these patients had true IgE-mediated allergy to LA, thus confirming the reported prevalence of LA allergy in large series to be <1% (0.97%). The protocols used in the investigation of these patients have also been discussed. Evidence from this review confirms the rarity of IgE-mediated allergy to LA and supports an investigation strategy based on using the clinical history to select patients for skin testing and challenge. We believe that such a triage process would alleviate pressures on allergy services without compromising patient safety.

Suspected allergy to local anaesthetics: follow-up in 135 cases

BACKGROUND

Local anaesthetics (LA) are generally considered safe with respect to allergy. However, various clinical reactions steadily occur. Even though most reactions are manifestations of reflexes to perceptive stimuli, uncertainty often remains regarding a possible allergic mechanism. This uncertainty later leads to an avoidance of local anaesthesia and unnecessarily painful interventions, resource-consuming general anaesthesia or even the risk of re-exposure to other yet unidentified allergens. In the present study, follow-up procedures at an allergy clinic were analysed to examine the frequency of identified causative agents and pathogenetic mechanisms and evaluate the strength of the diagnostic conclusions.

METHOD

The medical records of 135 cases with alleged allergic reactions to LA were reviewed. Diagnoses were based on case histories, skin tests, subcutaneous challenge tests and in vitro IgE analyses.

RESULTS

Two events (1.5%) were diagnosed as hypersensitivity to LA, articaine-adrenaline and tetracaine-adrenaline, respectively. Ten reactions (7%) were diagnosed as IgE-mediated allergy to other substances including chlorhexidine, latex, triamcinolone and possibly hexaminolevulinate. As challenge testing was not consistently performed with the culprit LA compound, follow-ups were short of definitely refuting hypersensitivity in 61% of the cases. The reported clinical manifestations were in general diagnostically unspecific, but itch and generalised urticaria were most frequent in test-positive cases.

CONCLUSION

Reactions during local anaesthesia are rarely found to be an IgE-mediated LA allergy. Whenever the clinical picture is compatible with allergy, other allergens should also be tested.

Hypersensitivity to local anaesthetics--update and proposal of evaluation algorithm

Local anaesthetics (LA) are widely used drugs. Adverse reactions are rare but may be caused by delayed-type hypersensitivity reactions and probably also immediate-type reactions. As it is not always easy to clinically differ between these subtypes, allergy skin testing should be considered. Although numerous test protocols have been published, how patients with hypersensitivity reactions to LA are ideally evaluated remains a topic of discussion. This review attempts to generate a comprehensive update on allergic reactions to LA and to present an algorithm that can be used for the evaluation of patients suspected with immediate- and delayed-type immune reactions. Literature was examined using PubMed-Medline, EMBASE, Biosis and Science Citation Index. Based on the literature, the proposed algorithm may safely and rapidly distinguish between immediate-type and delayed-type allergic immune reactions.