Predictive Value Of Skin Testing Research Articles

Predictive value of skin testing with excipients for COVID-19 vaccines

Coronavirus disease 2019 (COVID-19) was declared a global pandemic by the World Health Organization (WHO) in March 2020. Despite the availability of therapies and the adoption of security measures, the most effective method to fight COVID-19 remains the induction of immunity through vaccines. Scientific communities have developed several types of COVID-19 vaccines since the beginning of the pandemic, including those with innovative messenger RNA (mRNA) technology. Patients with a history of allergic reactions may have an increased risk of hypersensitivity reactions to COVID-19 vaccines. Therefore, it is important that these patients are evaluated by an allergist to help monitor immediate-type adverse reactions and identify what vaccine component may elicit an allergic reaction. Various strategies have been suggested to prevent hypersensitivity reactions, including performing skin tests or in vitro tests before vaccination in high-risk patients, administering a different vaccine for the second dose in subjects reporting adverse reactions to the first dose, fractional dosing, or pretreating with anti-immunoglobulin E (IgE) monoclonal antibody. The scope of this review is to evaluate, through current evidence available in the literature, the accuracy of skin testing to the excipients of COVID-19 vaccines, especially polyethylene glycol (PEG) and polysorbate, in predicting allergic reactions to vaccination, despite the existing discordance of data and approaches to the question from the various clinical experiences, as to permit the safe administration of COVID-19 vaccines to populations around the globe.

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

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. 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. 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. 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.

Revaccination and Adverse Event Recurrence in Patients with Adverse Events following Immunization

To estimate the risk of recurrence of adverse events following immunization (AEFIs) upon revaccination and to determine among patients with suspected vaccine allergy whether allergy skin test positivity was associated with AEFI recurrence. This prospective observational study included patients assessed in the Canadian Special Immunization Clinic Network from 2013 to 2019 with AEFIs who required revaccination with the vaccine temporally associated with their AEFI. Participants underwent standardized assessment and data collection. Special Immunization Clinic physicians used guidelines to inform their recommendations. Participants were followed up after revaccination to capture AEFI recurrences. Data were transferred to a central database for descriptive analysis. Overall, 588 participants were assessed for 627 AEFIs; 570 (91%) AEFIs occurred in children <18years of age. AEFIs included immediate hypersensitivity (130/627; 21%), large local reactions (110/627; 18%), nonurticarial rash (51/627; 8%), seizures (26/627; 4%), and thrombocytopenia (11/627; 2%). Revaccination was recommended to 513 of 588 (87%) participants. Among participants recommended and due for revaccination during the study period, 63% (299/477) were revaccinated. AEFI recurrence was 10% (31/299) overall, 31% (15/49) for large local reactions, and 7% (5/66) for immediate hypersensitivity. No recurrence was serious. Among 92 participants with suspected vaccine allergy who underwent skin testing and were revaccinated, the negative predictive value of skin testing for AEFI recurrence was 96% (95% CI 92.5%-99.5%). Most individuals with AEFIs were safely revaccinated. Among those with suspected vaccine allergy, skin testing may help determine the safety of revaccination.

Non-immediate hypersensitivity reactions to iomeprol: Diagnostic value of skin tests and cross-reactivity with other iodinated contrast media.

Iodinated contrast media produce non-immediate hypersensitivity reactions (NIHR). The goal of this prospective study was to determine the utility of skin tests and the subsequent tolerance to negative skin-tested iodinated contrasts in patients with NIHR caused by iomeprol. Prick and intradermal tests with iomeprol, iopamidol, iopromide, and iobitridol were performed in all patients. IV challenge with the causative contrast (iomeprol in 90%) was made if skin tests were negative. In case of a positive skin test with the causal contrast, or a positive challenge test with it, IV challenge test with an alternative, negative skin-tested contrast was performed in all patients. Skin tests were positive in 47.6% (20/42) of patients with NIHR induced by iomeprol. Of the 66 challenge tests performed with negative skin-tested iodinated contrasts, tolerance was confirmed in 35 (53%): 32 iomeron, 2 iobitridol, 1 iopamidol. Cross-reactivity between iomeprol and iopamidol was 22% (4/20 in patients with positive skin tests and 5/21 in patients with negative skin tests). Sensitivity of the skin tests was less than 50% NIHRs due to iomeprol, while the negative predictive value of skin tests in patients who tolerated challenges with alternative contrasts (mainly iopamidol) was 53% (35 tolerated out of 66 performed). The cross-reactivity between iomeprol and iopamidol is high.

Amoxicillin hypersensitivity: Patient outcomes in a seven-year retrospective study

BackgroundThe beta-lactam antibiotic amoxicillin and the beta-lactamase inhibitor clavulanic acid in combination with amoxicillin are known to cause both immediate- and nonimmediate-type hypersensitivity. ObjectiveTo characterize a large cohort of patients with a history of amoxicillin or amoxicillin-clavulanic acid hypersensitivity. MethodsA retrospective analysis was conducted of the demographics, presentation, investigation, and management of 331 patients presenting to 1 allergy center with a history of hypersensitivity to amoxicillin or amoxicillin-clavulanic acid. ResultsHypersensitivity was confirmed in 37 of 221 patients (17%) who took amoxicillin and 47 of 110 patients (43%) who took amoxicillin-clavulanic acid as the index drug.In immediate hypersensitivity, skin test results confirmed the diagnosis in 66 of 139 patients (47%). Penicillin cross-reactivity was observed in 16 of 36 patients (44%). Of the 16 patients who were cross-reactive, 13 (81%) reacted to amoxicillin-clavulanic acid as the index drug. All patients who had negative skin test results (73/139) underwent drug provocation. The negative predictive value of skin tests was 89%.In nonimmediate hypersensitivity, delayed intradermal tests confirmed diagnosis in 12 of 170 patients (7%). Of the 12 patients whose skin test results were positive, 8 (67%) presented with drug reaction with eosinophilia and systemic symptoms. All patients with a negative skin test result (158/170) underwent drug provocation. The negative predictive value of skin tests was 95%. Penicillin cross-reactivity was observed in 3 of 12 patients (25%).Ten patients were diagnosed with hypersensitivity to clavulanic acid. ConclusionThe negative predictive value of skin tests in both immediate and nonimmediate hypersensitivity reactions is excellent and excludes severe allergy. Nonimmediate hypersensitivity is rare. Confirmed hypersensitivity is more likely if amoxicillin-clavulanic acid is the index drug. Cross-reactivity was more common in patients presenting with immediate hypersensitivity, typically involving benzylpenicillin. A minority of patients were allergic to clavulanic acid.

Evaluation of skin test indications for general anesthetics in real life: a prospective cohort study

BackgroundIn daily practice, atopic patients and those who have other drug allergies are referred to allergy clinics for evaluation of possible general anesthetic allergy despite the fact that it is not recommended in recent guidelines. ObjectiveThe aim of this prospective study is to determine the negative predictive value of skin tests for common general anesthetic drugs prior to general anesthesia in atopic patients and in patients who had drug allergies by including the data of those who had previously tolerated or reacted to general anesthesia. MethodsA database program was constituted to collect the preoperative skin test data of patients referred to our clinic between 2013 and 2018. Demographic and clinical history, medications implemented during perioperative period, reactions, and results of skin tests performed with anesthetic drugs and latex were evaluated. ResultsFour hundred fifty-nine out of the total 1167 patients referred fulfilled the inclusion criteria for further evaluation. Nearly 75% of the patients were female and mean age was 46.3 ± 14.3 years. History of hypersensitivity reactions (HRs) due to NSAIDs and/or antibiotics, radiocontrast agents, local anesthetics, and food were present in the 53.1%, 4.1%, 1.5%, and 2.0%, respectively. The negative predictive values of skin tests for general anesthetics were in the range of 80–100%. Only 4 patients (0,87%) experienced HRs during operation. ConclusionThese real-life data reveal high rates of negative predictive value of skin tests with general anesthetic drugs and a low reaction rate in atopic patients and in patients with allergy to other drugs.

Potential mechanisms of anaphylaxis to COVID-19 mRNA vaccines

Anaphylaxis to vaccines is historically a rare event. The coronavirus disease 2019 pandemic drove the need for rapid vaccine production applying a novel antigen delivery system: messenger RNA vaccines packaged in lipid nanoparticles. Unexpectedly, public vaccine administration led to a small number of severe allergic reactions, with resultant substantial public concern, especially within atopic individuals. We reviewed the constituents of the messenger RNA lipid nanoparticle vaccine and considered several contributors to these reactions: (1) contact system activation by nucleic acid, (2) complement recognition of the vaccine-activating allergic effector cells, (3) preexisting antibody recognition of polyethylene glycol, a lipid nanoparticle surface hydrophilic polymer, and (4) direct mast cell activation, coupled with potential genetic or environmental predispositions to hypersensitivity. Unfortunately, measurement of anti–polyethylene glycol antibodies in vitro is not clinically available, and the predictive value of skin testing to polyethylene glycol components as a coronavirus disease 2019 messenger RNA vaccine-specific anaphylaxis marker is unknown. Even less is known regarding the applicability of vaccine use for testing (in vitro/vivo) to ascertain pathogenesis or predict reactivity risk. Expedient and thorough research-based evaluation of patients who have suffered anaphylactic vaccine reactions and prospective clinical trials in putative at-risk individuals are needed to address these concerns during a public health crisis.

Piperacillin-Tazobactam Allergies: An Exception to Usual Penicillin Allergy.

PurposeThe majority of penicillin allergy labels are false, and skin tests (ST) have high negative predictive value (NPV) of up to 90%. Piperacillin-tazobactam (PT) allergy has been suspected to be an exception to this, but existing literature is scarce. We investigate the epidemiology, clinical characteristics, testing outcomes and predictive value of ST in patients referred for suspected PT allergies.MethodsThe records of all patients referred for suspected PT allergy testing and prescription rates of PT in all Hong Kong public hospitals (2015–2019) were analyzed.ResultsThere was an increase in both PT prescriptions and number of newly reported PT allergies between 2015 and 2019. The majority (91.1%) of patients with suspected PT allergy had at least 1 underlying medical co-morbidity or immunosuppressant use leading to increased risk of infections. Thirty-six patients with suspected PT allergy completed ST. Two patients had positive ST, and 32/34 patients with negative ST underwent drug provocation testing (DPT). Nine of these patients were diagnosed with PT allergy based on positive DPT. Overall, 11/34 (32.4%) were diagnosed with PT allergy and the NPV of ST was 71.9%.ConclusionsThere is growing utilization of PT and corresponding cases of suspected allergies. The majority of suspected PT allergies had increased risk for recurrent infections. Unlike other penicillin allergy, there is a high rate of genuine PT allergy (up to 30%) and a poor NPV of ST (up to 70%). DPT remains the gold standard for accurate diagnosis, and all patients with a suspected allergy should undergo thorough allergy workup.

Drug Challenge Tests With General Anesthetics: Predictive Value of Skin Tests.

The study of perioperative drug reactions remains a major challenge for both diagnosis and therapy. The lack of a standard assessment of allergy to general anesthetics and of data establishing the true value of skin tests for most drugs used in induction and maintenance of anesthesia, as well as the lack of commercially available reagents for in vitro tests, renders the study of these reactions problematic. The aims of this study were to provide a diagnostic protocol for drug challenge testing with general anesthetics, to establish an etiological diagnosis that is as specific as possible, and to determine the predictive value of skin tests. Twenty-nine patients with perioperative drug reactions were included in the study from November 2008 to December 2018. We confirmed the high negative predictive value of the tests (96%-100%) in the case of propofol, rocuronium, and fentanyl. To our knowledge, this is the first study to describe drug challenge testing with general anesthetics and, therefore, to establish the true negative predictive value of skin tests, which leads to a definitive diagnosis and safer surgery. After assessing risks and benefits and considering the importance of this group of drugs, we conclude that drug challenge testing with general anesthetics is necessary. We propose a protocol for perioperative drug reactions that enables us to make a highly accurate etiological diagnosis with minimum risk for the patient.

Features of in vivo diagnostics of delayed drug hypersensitivity to beta-lactams

Background. Beta-lactams are the most widely used group of antibacterial agents. They are used for treating of infectious complications of varying severity, including urgent situations. The exclusion of the entire beta-lactam group not only leads to a significant increase in the cost of treatment, length of hospitalization and the formation of resistance of the flora to alternative antibiotics, but also may be life threatening in some cases. Therefore, correct diagnosis and establishement of the offending medication can prevent the development of allergic reactions and to avoid unreasonable lifelong bans on the use of certain medications, which often lead to a decrease of the effectiveness of treatment and increase its cost. The aim of the study was to develop the diagnostic and management algorithm and of of patients with presumptive diagnosis of delayed drug hypersensitivity to beta-lactams. Materials and methods. A comprehensive in-depth examination, including in vivo tests with beta-lactams was done in 53 patients (37 - 70% women, and 16 - 30% men) with a presumptive diagnosis of delayed drug hypersensitivity to beta-lactams. The minimum age at the time of the reaction was 4 years, the maximum age was 86 years, the average age was 37 years,the median was 38,5 years old. The minimum age at the time of testing was 6 years, the maximum age was 89 years, the average age was 44 years, median was 44 years old. Results. In the group of patients with delayed drug hypersensitivity to beta-lactams (n=21) the diagnosis was confirmed by skin testing in 19 (90,5%) patients, in 18 (85,7%) to aminopenicillins, and 1 (4,8%) to ceftriaxone. In 2 (9,5%) cases, the diagnosis was established using a drug provocation test: for amoxicillin (4,8%) and for ceftriaxone (4,8%). According to the obtained data, the specificity of skin tests for the diagnostics of delayed drug hypersensitivity to beta-lactams was 100%. In case of delayed drug hypersensitivity to aminopenicillins, the sensitivity of skin tests was 94,7%, the negative predictive value of skin tests was 93,7%, the overall accuracy of skin testing was 97%, and the incidence of false-negative results was 5,3%. Conclusion. Skin testing is promising and safe in the diagnositics of delayed drug hypersensitivity to beta-lactams. It allows to exclude unreasonable contraindications for the use of beta-lactams, thereby increasing the effectiveness of treatment while reducing economic costs.

Workgroup Report by the Joint Task Force Involving American Academy of Allergy, Asthma & Immunology (AAAAI); Food Allergy, Anaphylaxis, Dermatology and Drug Allergy (FADDA) (Adverse Reactions to Foods Committee and Adverse Reactions to Drugs, Biologicals, and Latex Committee); and the Centers for Disease Control and Prevention Botulism Clinical Treatment Guidelines Workgroup-Allergic Reactions to Botulinum Antitoxin: A Systematic Review.

Naturally occurring botulism is rare, but a large number of cases could result from unintentional or intentional contamination of a commercial food. Despeciated, equine-derived, heptavalent botulinum antitoxin (HBAT) is licensed in the United States. Timely treatment reduces morbidity and mortality, but concerns that botulinum antitoxin can induce anaphylaxis exist. We sought to quantify the allergy risk of botulinum antitoxin treatment and the usefulness of skin testing to assess this risk. We conducted a systematic review of (1) allergic reactions to botulinum antitoxin and (2) the predictive value of skin testing (ST) before botulinum antitoxin administration. We searched 5 scientific literature databases, reviewed articles' references, and obtained data from the HBAT manufacturer and from the Centers for Disease Control and Prevention. Anaphylaxis incidence was determined for HBAT and previously employed botulinum antitoxins. We calculated the positive predictive value (PPV) and negative predictive value (NPV) of ST for anaphylaxis related to HBAT and other botulinum antitoxins. Seven articles were included. Anaphylaxis incidence was 1.64% (5/305 patients) for HBAT and 1.16% (8/687 patients) for all other botulinum antitoxins (relative risk, 1.41 [95% confidence interval, .47-4.27]; P = .5). Observed values for both PPV and NPV for HBAT-ST (33 patients) were 100%. Observed PPVs and NPVs of ST for other botulinum antitoxins (302 patients) were 0-56% and 50%-100%, respectively. There were no reports of fatal anaphylaxis. Considering the <2 % rate of anaphylaxis, fatal outcomes, modest predictive value of ST, resource requirements for ST, and the benefits of early treatment, data do not support delaying HBAT administration to perform ST in a mass botulinum toxin exposure. Anaphylactic reactions may occur among 1%-2% of botulinum antitoxin recipients and will require epinephrine and antihistamine treatment and, possibly, intensive care.

Oral challenge without skin tests in children with non‐severe beta‐lactam hypersensitivity: Time to change the paradigm?

Suspected allergy to penicillins and cephalosporins is very common in childhood. After a proper evaluation, allergy will be confirmed only in a small portion of them. Intradermal tests are usually part of the allergy workup, but they are painful for children and time-consuming, and their role has been debated. A systematic review found only two studies reporting a positive predictive value of skin tests in children of 36% and 33%, respectively, leading to a high rate of inaccurate diagnosis. Moreover, considering that skin tests are negative in more than 90%-95% of cases, an oral provocation test (OPT) is finally needed to confirm tolerance in most of these children. Positive OPT are rare, and even where children demonstrate reproducible signs on challenge, they rarely constitute immediate or serious symptoms. Therefore, OPT to the index antibiotic without skin tests are increasingly being considered an accepted procedure for children with a suspected mild non-immediate reaction related to a beta-lactam antibiotic. Furthermore, a recent research has taken the same approach including children with suspected mild immediate reactions, with similar safety and positive results. In light of recent evidence highlighted, it is now the time for large and multicentric studies to confirm that OPT with the index antibiotic, without skin tests, are safe and convenient for children with a history of a mild reaction with a beta-lactam antibiotic before it can be recommended in pediatric allergy guidelines.

P002 Predictive value of skin testing to omalizumab and excipients

P002 Predictive value of skin testing to omalizumab and excipients

Analysis of cross-reactivity among radiocontrast media in 97 hypersensitivity reactions

Results Ninety-seven patients were included. CR occurred between ionic monomers (IMs) in 2 cases, between non-ionic monomers (NIMs) in 93 cases, between an ionic dimer (ID) and an IM in 1 case, between NIMs and IMs in 38 cases, between NIMs and IDs in 29 cases, between non-ionic dimers (NIDs) and IMs in 9 cases, between IDs in 13 cases, and between NIMs in 65 cases. Multiple correspondence analyses identified two subgroups of RCM in which CR was frequent: Group A (iodixanol, iopamidol, iomeprol, iohexol, ioversol), which share two identical N-(2, 3-dihydroxypropyl) carbamoyl side chains that could be the antigen determinant (also present in other drugs), and Group B (ioxaglate, iobitridol). Conclusion From this largest study of CR between RCM, we demonstrate that frequent CR between RCM does not follow the current chemical classification. Thus, we propose reclassifying RCM, and also suggest re-challenging sensitized patients with RCM from a different CR subgroup than that of the RCM initially involved.

Indications, Protocols, and Outcomes of Drug Desensitizations for Chemotherapy and Monoclonal Antibodies in Adults and Children

Advances in the understanding of various malignancies and chronic inflammatory diseases has led to the development of better treatment options for prolonging patient survival and minimizing morbidity. The recognition of "first-line" chemotherapy and monoclonal agents for these conditions has given more urgency to the need to re-administer these drugs in cases of drug hypersensitivity reactions. Therefore, in these cases, not only is desensitization considered when there is no alternative therapy available but also when alternative treatments are considered therapeutically inferior and/or more toxic. In this article, we describe the steps involved in the evaluation of these patients, factors to consider before making a decision to desensitize, the implementation of desensitization protocols, and the outcomes of such procedures.

Comparative dietary therapy effectiveness in remission of pediatric eosinophilic esophagitis

Eosinophilic esophagitis is a chronic, immune-mediated inflammatory disorder that responds to dietary therapy; however, data evaluating the effectiveness of dietary therapeutic strategies are limited. This study compared the effectiveness of 3 frequently prescribed dietary therapies (elemental, 6-food elimination, and skin prick and atopy patch-directed elimination diets) and assessed the remission predictability of skin tests and their utility in directing dietary planning. A retrospective cohort of proton-pump inhibitor-unresponsive, non-glucocorticoid-treated patients with eosinophilic esophagitis who had 2 consecutive endoscopic biopsy specimens associated with dietary intervention was identified. Biopsy histology and remissions (<15 eosinophils/high-power field) after dietary therapy and food reintroductions were evaluated. Ninety-eight of 513 patients met the eligibility criteria. Of these 98 patients, 50% (n= 49), 27% (n= 26), and 23% (n= 23) received elemental, 6-food elimination, and directed diets, respectively. Remission occurred in 96%, 81%, and 65% of patients on elemental, 6-food elimination, and directed diets, respectively. The odds of postdiet remission versus nonremission were 5.6-fold higher (P= .05) on elemental versus 6-food elimination diets and 12.5-fold higher (P= .003) on elemental versus directed diets and were not significantly different (P= .22) on 6-food elimination versus directed diets. After 116 single-food reintroductions, the negative predictive value of skin testing for remission was 40% to 67% (milk, 40%; egg, 56%; soy, 64%; and wheat, 67%). All 3 dietary therapies are effective; however, an elemental diet is superior at inducing histologic remission compared with 6-food elimination and skin test-directed diets. Notably, an empiric 6-food elimination diet is as effective as a skin test-directed diet. The negative predictive values of foods most commonly reintroduced in single-food challenges are not sufficient to support the development of dietary advancement plans solely based on skin test results.

Value Of Skin Testing Solely With Penicillin G In Children With a History Of Penicillin Allergy

For most part of the last decade, PrePen® has been unavailable commercially. This situation has compromised the evaluation of many patients with a history of penicillin allergy. During this period, evaluation of children with a history of penicillin allergy continued in our center using penicillin G as the sole reagent for skin testing. We aimed to determine the negative predictive value and safety of this approach. We reviewed the files of all patients evaluated for a history of penicillin allergy between December 2006 and December 2009 at the CHU Sainte-Justine Allergy Clinic. Evaluation consisted of skin testing with penicillin G 10,000 IU/mL followed if negative by a graded challenge to the culprit penicillin. We evaluated 563 patients during this period. Among these, 185 (32.9%) had a positive skin test to penicillin G and 378 (67.1%) had a negative skin test. A reaction occurred in 4.8% (18/375) of patients following challenge. Three patients were not challenged. All reactions were mild and generally limited to the skin. The negative predictive value of skin testing solely with penicillin G was calculated at 95.2% (92.5-97.1%). This study raises questions about the relevance of skin testing children with a history of penicillin allergy with a large array of skin test reagents as the negative predictive value of penicillin G alone approximates that of the recommended approach. Also, it offers support for a simpler and safe alternative to skin testing in these children using penicillin G as the sole skin test reagent.

Negative predictive value of skin tests to neuromuscular blocking agents

Allergy to neuromuscular blocking agents (NMBAs) is the most important caue of perioperative anaphylaxis in France. The diagnosis relies on a careful clinical history, the search of serum IgE antibodies, and the realization of skin tests. Although the skin tests are the most important tool and their sensitivity is widely recognized, the lack of information about their negative predictive value represents an important issue in the management of patients who require a new procedure with NMBA injection. We present a series of 49 patients with confirmed allergy to NMBAs, six of whom required a subsequent surgery with neuromuscular blockade. Negative skin tests allowed the selection of an alternative NMBA, which was well tolerated in all 6 cases. We found an excellent negative predictive value of skin tests in our series but larger studies are required to properly address this question.

Delayed hypersensitivity reactions caused by iodixanol: An assessment of cross-reactivity in 22 patients

Delayed hypersensitivity reactions caused by iodixanol: An assessment of cross-reactivity in 22 patients

The predictive value of skin testing in the diagnosis of local anesthetic allergy

Local anesthetics are commonly used medications and can result in adverse reactions. The diagnostic workup of local anesthetic reactions remains controversial. This study was designed to determine the effectiveness of skin testing for local anesthetic allergy evaluation. A retrospective chart review was performed on patients undergoing local anesthetic skin testing. Patients were included if they underwent prick and intradermal skin testing followed by incremental subcutaneous challenge. Charts were further systematically reviewed to evaluate response to local anesthetics in the clinical setting after open subcutaneous challenge. One hundred seventy-eight patients underwent 227 local anesthetic skin tests. Two hundred twenty (97%) of the skin tests were negative. Of the negative skin tests results, 214 (97%) had negative challenge or probable non-IgE-mediated events during challenge. Three patients with six negative skin tests had a local reaction during the open subcutaneous challenge. Seven skin tests on five patients met the criteria for a positive skin test with local anesthetics. One patient had an equivocal local skin reaction with subcutaneous challenge without systemic effects. Three patients had a negative subcutaneous challenge and one patient did not undergo a challenge. Ninety-eight percent of patients receiving local anesthetics in the clinical setting after open subcutaneous challenge tolerated the medications. The negative predictive value of the local anesthetic skin test was 97% with few positive skin tests. Positive local anesthetic skin tests are uncommon and the local anesthetic skin tests have an excellent negative predictive value. Additional study with skin test-only protocols is warranted.