History Of Immediate Reactions Research Articles

Clavulanic Acid Is a Leading Culprit Beta-Lactam in Immediate Allergic Reactions to Penicillins.

Clavulanate, a beta-lactam associated with amoxicillin, is frequently prescribed in patients at all ages. Recent data implicate amoxicillin-clavulanate in up to 80% of beta-lactam allergy cases. We assessed clavulanate's role in inducing allergic reactions to this combination treatment, with a focus on selective immediate reactions. Adults (≥ 16 years) reporting a history of immediate reactions to amoxicillin-clavulanate were evaluated through a beta-lactam allergological workup, using modified European Academy of Allergy and Clinical Immunology guidelines. Patients first underwent skin testing, and if negative, drug provocation tests. Expected outcomes were: Group A, subjects with immediate reaction to classical penicillin group determinants (penicilloyl polylysine, minor determinants mixture, and/or penicillin G); Group B, subjects with selective immediate reaction to amoxicillin; Group C, subjects with selective immediate reaction to clavulanate and Group D, those immediate reactions with co-sensitization to clavulanate plus penicillin group determinants or amoxicillin. Of 1,170 included patients, 104 had immediate reactions: 36.5% to penicillin group determinants (Group A), 26.9% to amoxicillin (Group B), 32.7% to clavulanate (Group C), and 3.8% to clavulanate plus penicillin determinants or amoxicillin (Group D). Diagnosis was made by skin testing in 79%, 75% and 47% of the patients, respectively, in the first 3 groups (P < 0.001). Drug provocation tests were necessary to establish most other diagnoses. Anaphylaxis predominated over urticaria/angioedema in all groups. Selective immediate reactions to clavulanate accounted for over a third of cases with confirmed reactions after amoxicillin-clavulanate intake, with more than half experiencing anaphylaxis. Within this group, skin test sensitivity was below 50%. People taking amoxicillin-clavulanate may also be co-sensitized to both drugs.

COVID-19 VACCINE ADMINISTRATION IN PATIENTS WITH FIRST-DOSE ADVERSE REACTIONS OR HISTORY OF SEVERE ALLERGIC REACTION

<h3>Introduction</h3> The COVID-19 pandemic has claimed over 6 million lives from 2020 onward. Vaccines against SARS-CoV-2 are one of our best tools in preventing severe illness and mortality. There have been multiple reactions reported to the SARS-CoV-2 vaccine that initially precluded further revaccinations, making protection against the virus incomplete. Our study aimed to identify true SARS-CoV-2 vaccine reactions, underlying patient risk factors, and to confirm the safety of our vaccine challenge protocol for revaccination. <h3>Methods</h3> Patients with reported adverse first-dose SARS-CoV-2 vaccine reactions precluding second dose, or those with history of severe allergic reaction were given a graded vaccine challenge of an initial 10% dose, observed for 30 minutes, with advancement to the 90% dose if no concerning reaction. <h3>Results</h3> Of the 50 patients enrolled, 49/50 (98%) were able to obtain the full vaccine dose. 8 (16%) of patients had a first dose reaction concerning for delayed hypersensitivity, and 7/8 of those patients tolerated the full repeat vaccine dose. 42 (84%) patients had history of immediate reaction to the first dose of the vaccine and all tolerated the full dose via challenge protocol. 1/50 patients needed epinephrine, but was able to fully obtain the dose with outpatient treatment during the course, and subsequent revaccination. <h3>Conclusion</h3> In a monitored setting, this challenge protocol is safe and effective for patients with history of adverse reaction to the vaccine or an underlying history of severe allergic reaction that would traditionally preclude repeat vaccination. The mechanism and pathophysiology of these reactions need to be elucidated through further research.

Second-dose mRNA COVID-19 vaccine safety in patients with immediate reactions after the first dose: Acase series.

BackgroundThe rates of suspected allergic reactions to the first dose of the coronavirus disease 2019 (COVID-19) mRNA vaccines have been reported to be as high as 2%, with an anaphylaxis incidence up to 2.5 per 10,000 individuals. Anaphylaxis in response to the first dose may be considered a contraindication to administration of the second dose, even though the second dose is necessary for optimal protection against severe disease. Many individuals with anaphylactic reactions to the first dose still want to receive a second dose. However, there are few published data to support the safety of administration of a second dose in this population.ObjectiveThe primary objective of this study was to determine the percentage of patients tolerating a second COVID-19 mRNA vaccine dose after an immediate reaction to the first dose.MethodsThis was a retrospective chart review of 47 patients at a Canadian hospital who had immediate, suspected allergic reactions following their first COVID-19 mRNA vaccine dose and received a second dose within our allergy clinic.ResultsOf 47 patients, 46 tolerated the second dose; 43% of patients developed mild, transient symptoms. There were no patients who developed anaphylaxis or needed epinephrine after the second dose.ConclusionOur case series adds to current evidence that administration of a second COVID-19 mRNA vaccine dose has a good safety profile in patients with a history of immediate reactions after the first dose, including those with a history of anaphylaxis in response to the first dose.

Management of Beta-Lactam Antibiotics Allergy: A Real-Life Study.

Beta-lactam allergy is a common problem in everyday medical practice and is recognized as a major public health issue. Carrying this label frequently leads to the avoidance of all beta-lactam antibiotics, favoring the use of other less preferred classes of antibiotics, that are more expensive and associated with more side effects and increased antimicrobial resistance. Therefore, delabeling a beta-lactam allergy is part of antimicrobial stewardship programs. Herein, we retrospectively examined the clinical records of 576 patients who were referred to our center for a label of allergy to beta-lactam antibiotics and were systematically investigated following a standardized algorithm. Our main aim was to evaluate the frequency of confirmed immediate- and delayed-type allergy to commonly prescribed subclasses of beta-lactam antibiotics (penicillin and cephalosporin), as well as the negative predictive value (NPV) and the sensitivity of skin tests. Our secondary aims were to examine the safety of beta-lactam skin testing and drug challenge. We identified that 260 patients reported a history of immediate reactions, 131 of delayed reactions, and 114 of unknown timing or mechanism of reactions. Following assessment and testing, 86 (18.3%) patients had a confirmed allergy to any beta-lactam antibiotics; 63 (13.4%) with an immediate- and 23 (4.9%) with a delayed-type reaction. Most frequently identified confirmed allergy was to penicillins (65 patients), followed by cephalosporins (21 patients). When immediate-type reactions were examined, NPV of skin tests were 96.3% and 100% for penicillins and cephalosporins, respectively. When delayed reactions were considered, NPV were 91.9 and 87.5% for penicillins and cephalosporins, respectively. Evaluation of the safety of skin tests according to the standardized procedure showed that systemic allergic reactions occurred in only 0.7% of skin tests and in 3.1% of drug challenges. Overall, our data indicate that only 18.3% of patients with a beta-lactam allergy label have a confirmed allergy and non-allergic patients can be safely delabeled through allergic workup based on skin tests and drug challenge. This approach supports the policy of saving second-line antibiotics through a standardized allergy workup.

MRNA COVID-19 vaccine safety in patients with previous immediate hypersensitivity to pegaspargase

mRNA COVID-19 vaccine safety in patients with previous immediate hypersensitivity to pegaspargase

Safe egg yolk consumption after a negative result for low-dose egg oral food challenge.

BackgroundHen's egg is one of the most common allergens causing infantile food allergy. Consuming heated egg yolk slightly contaminated with egg white (EY with scEW) improves diet quality. Most children with egg allergies can safely consume 1/25 of a heated whole egg (low‐dose egg). Although low‐dose egg has similar antigenicity to EY with scEW, clinical reproducibility is unknown. We aimed to examine the safety of EY with scEW consumption after a negative result of low‐dose egg oral food challenge (OFC).MethodsIn this prospective study, children aged <18 years with a history of immediate reaction to eggs were enrolled. We advised children and guardians to consume EY with scEW after a negative result of low‐dose egg OFC and to record symptoms, if any.ResultsWe evaluated 276 children with negative results for low‐dose egg OFC who had previously shown reactivity to eggs. Their median age was 1.2 years. Boys accounted for 188 (68%) of the children. The median egg white‐specific immunoglobulin E level was 11.7 kUA/L. At home, six children experienced mild symptoms. Skin symptoms were the most common. Among the six children, five were confirmed to continue the consumption of EY with scEW and one developed mild respiratory symptoms and continued to avoid eating eggs.ConclusionAlthough a few children with egg allergies experience mild symptoms, most of them can ultimately consume EY with scEW. Consumption of EY with scEW after low‐dose egg OFC seems safe and may improve their quality of life by making egg yolk products available.

The use of in vivo and in vitro tests in children with beta lactam allergy

BackgroundDrug allergies are reactions within the context of drug hypersensitivity reactions, which are caused by immunological mechanisms due to a previously sensitising drug. Beta-lactam antibiotics (BLA) are the leading agents causing drug hypersensitivity reactions in children.The aim of this study is to evaluate the diagnostic importance of in vivo and in vitro diagnostic tests in children with suspected immediate-type BLA hypersensitivity and to investigate the frequency of their use for the final diagnosis. MethodsPatients admitted to the Outpatient Clinic of Division of Paediatric Allergy and Immunology with suspicion of immediate-type BLA hypersensitivity between December 2014 and December 2018 were investigated. Patients with a history of immediate reactions to BLA were examined by performing drug specific IgE, skin prick tests, intradermal tests and drug provocation tests (DPT). ResultsDuring the study period, 148 patients were admitted to our clinic with suspected immediate-type BLA hypersensitivity. Forty-eight patients completed all assessment steps and were enrolled in the study. It has been shown that 27 patients did not have drug allergy. BLA hypersensitivity was proven in 21 patients by using in vivo test algorithm. More than half of the patients were diagnosed via skin tests with culprit drug. ConclusionAllergy work-up should be performed in patients with immediate reactions to BLA. A skin test can demonstrate BLA hypersensitivity in most patients. Thus, skin tests should be performed prior to the drug provocation test.

Oral Food Challenge Failures Among Foods Restricted Because of Atopic Dermatitis

To evaluate the frequency of office-based oral food challenge (OFC) failures to previously tolerated foods eliminated from diets to treat atopic dermatitis (AD) based on positive skin prick test (SPT) results and/or specific immunoglobulin E (sIgE) testing.A total of 442 patients were included who had undergone OFCs to peanut, wheat, soy, milk, and egg (the top 5 allergens in the United States) at the allergy clinics of Riley Hospital for Children at Indiana University Health from 2008 to 2014.By retrospective chart review, subjects were classified into 3 groups according to the reason for food avoidance, as follows: food allergy (defined as typical signs of an allergic reaction within 2 hours of ingestion, with supporting SPT or sIgE results), sensitization without introduction (food item never introduced because of positive SPT and/or sIgE results found during evaluation for AD or other food allergies), and avoidance based on positive SPT and/or sIgE test results found during AD workup (all had previously tolerated the food without reaction within 2 hours). OFCs were offered if the subject had sIgE levels predicting passing the OFC on the basis of 95% positive predictive values and no reaction to the food in the last 12 months. Plain and extensively heated milk OFCs were grouped together, as were those for egg. Extensively heated food challenges were offered regardless of sIgE levels. Total IgE levels were not reported.Indications for OFCs were a history of food allergy (320 of 442, 72.4%) and sensitization (77 of 442, 17.4%) and AD (45 of 442, 10.2%). There were no significant differences among these 3 groups at OFC in age, sex, race, asthma, allergic rhinitis, or percentage of positive SPT results to the food. The overall OFC failure rate was 20.1%, including 21.9% of the food allergy group, 16.9% of the sensitization group, and 13.3% of the AD group, which was not statistically significant comparing groups (P = .30). There was no significant difference with regard to OFC pass and fail rates among the 5 foods challenged or the length of time of food avoidance (range: 3–120 months, P = .97). Wheat was significantly more likely to be avoided because of AD (P < .001), and milk was likely to be avoided because of food allergy (P = .002).In this study, 13.3% of children with AD who had removed a previously tolerated food from their diet because of a positive SPT and/or sIgE test result failed an OFC to that food in as quickly as after 3 months of avoidance. This demonstrates the potentially rapid loss of tolerance that can occur with food elimination for AD therapy and bolsters evidence that SPT and/or sIgE test results in patients with AD who do not have a history of immediate reaction to the foods tested are often clinically irrelevant.Data on the role of food triggers in AD have been conflicting, but overall there is lack of high-quality evidence. Aggressive skin care regimens should be pursued over elimination diets, which carry the risk of loss of tolerance to a food previously consumed without immediate reaction.

Suspected Reaction With Cephalosporin May Be a Predictive Factor for β-Lactam Allergy in Children

To determine the frequency and risk factors of confirmed allergy in patients who report β-lactam allergy and evaluate cross-reactivity between β-lactams in children with confirmed allergy.The population included 67 children evaluated at an academic allergy and immunology practice in Turkey from 2012 to 2017.All patients referred to an outpatient clinic with history of immediate reaction to β-lactam antibiotics were included. Patients completed a questionnaire and underwent workup on the basis of the European Network for Drug Allergy guidelines. Serum-specific immunoglobulin E to penicilloyl V, penicilloyl G, amoxicilloyl, and ampicilloyl were measured by UniCAP in all patients. Patients with undetectable serum results underwent skin prick tests (SPTs). Intradermal testing was performed if the SPT result was negative. A drug provocation test with suspected β-lactam was performed in patients with negative workup.β-lactam allergy was confirmed in 14.9% of patients who reported a history of allergy. All of the allergic patients had negative results on SPT and serology. Four patients with negative intradermal results had a reaction (urticaria) with the drug provocation test. Age, sex, time interval since reaction, atopy, reaction type, parental history of drug allergy, and multiple drug allergy history were not significantly different between allergic and tolerant patients. The rate of confirmed diagnosis was higher for the group that reported cephalosporin allergy compared with report of penicillin allergy (P = .03). Three patients with allergy to penicillin tolerated cefuroxime. Four patients with selective allergy to ceftriaxone tolerated cephalosporins with dissimilar side chains.Appropriate evaluation of suspected drug allergy will lead to accurate diagnoses and reduce the use of less-effective yet more-expensive alternative antibiotics.This study supports a large body of literature demonstrating that most patients who report a β-lactam allergy tolerate the drug. Neither serum immunoglobulin E testing nor SPT alone are sufficient to evaluate β-lactam allergy. Even intradermal testing may miss some truly allergic patients. The gold standard, drug provocation challenge, is required to confirm a diagnosis of allergy. The clinical history and available diagnostic results must be weighed to determine if drug provocation challenge is appropriate because reactions in allergic individuals can be potentially life-threatening.

Sulfonamide Hypersensitivity: Fact and Fiction

Sulfonamide antimicrobials are commonly reported as causing drug allergy and have been implicated in a variety of hypersensitivity reactions including immediate IgE-mediated reactions, benign T-cell-mediated rashes, and severe cutaneous adverse reactions such as Stevens-Johnson syndrome, toxic epidermal necrolysis, and drug reaction with eosinophilia and systemic symptoms. Cross-reactivity is unlikely between sulfonamide antimicrobials and sulfonamide non-antimicrobials. In patients who develop reactions to a sulfonamide non-antimicrobial, there is no evidence to suggest that sulfonamide antimicrobials and other sulfonamide non-antimicrobials would cross-react. Although immediate skin testing can be performed in patients with histories of immediate reactions, they are infrequently positive and wane over time. Delayed skin testing including patch tests to sulfonamides is rarely positive. Drug challenges are a useful tool for patients with both immediate and delayed reactions to sulfonamides. The role of sulfamethoxazole desensitization is controversial as rates of hypersensitivity reactions are similar between desensitization and drug challenge.

Accuracy of serum IgE concentrations and papule diameter in the diagnosis of cow's milk allergy

ObjectiveTo compare serum concentrations of specific IgE and mean papule diameters induced in the immediate skin reactivity test with cow's milk and its fractions with results of the oral challenge test, and to establish cutoff points capable of predicting clinical reactivity to cow's milk in patients treated at a referral service. MethodsOne hundred and twenty‐two children (median of 17 months) with a history of immediate reactions to cow's milk and presence of specific IgE for cow's milk and/or its fractions (positive skin and/or IgE serum tests) were submitted to open oral challenge test with cow's milk. ResultsThe oral challenge test was positive in 59.8% of the children, 49% of whom were males. Serum levels of specific IgE, as well as mean cow's milk papule diameters, were significantly higher in allergic patients (medians: 3.39kUA/L vs. 1.16kUA/L, 2.5mm vs. 0mm). The optimal cutoff points (Youden's index) of serum IgE specific for cow's milk and its fractions capable of predicting cow's milk reactivity (positive oral challenge test) were: 5.17kUA/L for cow’s milk, 0.95kUA/L for α‐lactalbumin, 0.82kUA/L for β‐lactoglobulin, and 0.72kUA/L for casein, whereas for papule diameters the cutoff points were 3.5mm for cow's milk and 6.5mm, 9.0mm, and 3.0mm for the α‐lactalbumin, β‐lactoglobulin, and casein fractions, respectively. ConclusionsThe cutoff points capable of predicting clinical reactivity to cow's milk were: 5.17kUA/L for serum‐specific IgE and 3.5mm for papule diameter measurement, values considered discriminatory for the diagnosis of cow's milk allergy.

Risk Factors and Clinical Features in Cashew Nut Oral Food Challenges

Background: Cashew nuts (CN) are capable of causing severe allergic reactions. However, little has been reported about the details of CN oral food challenges (OFC). Methods: CN-specific IgE (sIgE) levels were measured for 1 year in 66 patients who underwent an OFC with >3 g CN for diagnosis or confirmation of tolerance acquisition between June 2006 and August 2014. We retrospectively analyzed the OFC and patient background. Results: The median (IQR) age of the 66 patients (48 boys/men and 18 girls/women) was 7.0 years (5.7-8.8). Twelve patients (18.2%) had a positive OFC result; 6 of 8 (75%) patients with a history of an immediate reaction to CN failed the OFC. Anaphylaxis was experienced by 5 of these 12 (42%) patients. A history of an immediate reaction to CN and the CN sIgE levels were significantly different for patients with a positive or negative OFC result (p < 0.01). Among patients without a previous immediate reaction to CN, the 95% positive predictive value (PPV) for the CN sIgE level for a positive OFC result was 66.1 kU_A/L. Conclusions: A history of an immediate reaction to CN and high CN sIgE were risk factors for a positive OFC result. The number of positive OFC results was relatively low, but there was a high probability of anaphylaxis. We should consider the indication of OFC carefully for patients with a history of immediate reactions to CN and avoid OFC for patients without such a history whose CN sIgE values are >66.1 kU_A/L (95% PPV).

Increased ratio of pollock roe-specific IgE to salmon roe-specific IgE levels is associated with a positive reaction to cooked pollock roe oral food challenge

BackgroundAnaphylaxis and immediate-type fish roe allergies have been reported worldwide, and, in Japan, fish roe is the sixth most common food allergen. No oral food challenges (OFCs) have used pollock roe (PR), which is reported to have high cross-reactivity with salmon roe (SR). Therefore, we administered an OFC using cooked PR to evaluate PR- and SR-specific immunoglobulin E (IgE) levels and allergic reactions in patients with PR sensitivity. MethodsThis retrospective study evaluating patient characteristics and responses to OFCs was conducted with 10–20 g of cooked PR, between April 2006 and November 2016. ResultsWe assessed 51 patients (median age: 6.8 years). All had PR sensitization, 6 (12%) with a history of immediate reactions to PR, and 18 (35%) of immediate reactions to SR. Median PR-specific and SR-specific IgE values were 3.4 kUA/L and 9.9 kUA/L, respectively. Seven patients (14%) had a positive OFC. There was no anaphylaxis. Induced symptoms were mild and included localized urticaria, throat pruritus, intermittent cough, and mild abdominal pain. We treated one patient with mild abdominal pain with oral antihistamines. There were no significant differences in history of immediate reaction to PR and PR-specific IgE titers between OFC-positive and OFC-negative patients, although significant differences were found for PR-specific IgE titers adjusted for SR-specific IgE (p = 0.025) and PR-specific IgE/SR-specific IgE ratio (p = 0.009). ConclusionsIncreased PR-specific IgE/SR-specific IgE ratio or PR-specific IgE levels adjusted for SR-specific IgE levels were risk factors for OFC positivity.

Accuracy of serum IgE concentrations and papule diameter in the diagnosis of cow's milk allergy

ObjectiveTo compare serum concentrations of specific IgE and mean papule diameters induced in the immediate skin reactivity test with cow's milk and its fractions with results of the oral challenge test, and to establish cutoff points capable of predicting clinical reactivity to cow's milk in patients treated at a referral service. MethodsOne hundred and twenty-two children (median of 17 months) with a history of immediate reactions to cow's milk and presence of specific IgE for cow's milk and/or its fractions (positive skin and/or IgE serum tests) were submitted to open oral challenge test with cow's milk. ResultsThe oral challenge test was positive in 59.8% of the children, 49% of whom were males. Serum levels of specific IgE, as well as mean cow's milk papule diameters, were significantly higher in allergic patients (medians: 3.39kUA/L vs. 1.16kUA/L, 2.5mm vs. 0mm). The optimal cutoff points (Youden's index) of serum IgE specific for cow's milk and its fractions capable of predicting cow's milk reactivity (positive oral challenge test) were: 5.17kUA/L for cow's milk, 0.95kUA/L for α-lactalbumin, 0.82kUA/L for β-lactoglobulin, and 0.72kUA/L for casein, whereas for papule diameters the cutoff points were 3.5mm for cow's milk and 6.5mm, 9.0mm, and 3.0mm for the α-lactalbumin, β-lactoglobulin, and casein fractions, respectively. ConclusionsThe cutoff points capable of predicting clinical reactivity to cow's milk were: 5.17kUA/L for serum-specific IgE and 3.5mm for papule diameter measurement, values considered discriminatory for the diagnosis of cow's milk allergy.

Oral Challenge without Skin Testing Safely Excludes Clinically Significant Delayed-Onset Penicillin Hypersensitivity

Penicillins are the drug family most commonly associated with hypersensitivity reactions. Current guidelines recommend negative skin tests (ST) before re-administering penicillins to patients with previous nonimmediate reactions (NIR). The objective of this study was to examine whether ST are necessary before re-administering penicillin to patients with NIR. Patients with NIR to penicillins starting longer than 1 hour after last dose administration or starting any time after the first treatment day or patients with vague recollection of their reaction underwent penicillin ST. Disregarding ST results, patients were challenged with the relevant penicillins. One-tenth of the therapeutic dose followed by the full dose was administered at 1-hour interval and patients continued taking the full dose for 5 days. A total of 710 patients with alleged BL allergy were evaluated. Patients with a history of immediate reaction (52, 7.3%) or cephalosporin allergy (16, 2.2%) were excluded. Of the remaining 642 patients, 62.3% had negative ST, 5.3% positive ST, and 32.4% equivocal ST. A total of 617 (96.1%) patients were challenged. Immediate reaction was observed in 9 patients (1.5%): 1-positive ST, 7-negative ST, and 1-equivocal ST (P= .7). Late reaction to the first-day challenge occurred in 24 patients (4%). An at-home challenge was continued by 491 patients. Complete 5-day and partial challenges were well tolerated by 417 (85%) and 44 patients (8.9%), respectively, disregarding ST results. Thirty patients (6.1%) developed mild reactions to the home challenge regardless of their ST results. A 5-day oral challenge without preceding ST is safe and sufficient to exclude penicillin allergy after NIR developing during penicillin treatment.

Reactions of Buckwheat-Hypersensitive Patients during Oral Food Challenge Are Rare, but Often Anaphylactic

Background: Buckwheat (BW) is a common cause of life-threatening allergy in Asia. Few have examined oral food challenges (OFCs) using BW. We here describe the OFC outcomes for the diagnosis or confirmation of tolerance acquisition and clarify risk factors for positive OFCs. Methods: Between July 2005 and March 2014, we retrospectively reviewed data from children who underwent OFCs using 3,072 mg of BW protein at Sagamihara National Hospital. Children were suspected of having BW allergy because of positive results for BW-specific IgE or because they had been previously diagnosed with BW allergy owing to immediate reactions to BW. Results: Of 476 such patients, we analyzed 419 aged 1-17 years (median age 6.7 years). Forty-four (10.5%) reacted to the BW OFC and 24 (54.5%) experienced anaphylaxis. Among patients with suspected BW allergies (n = 369), 30 (8.1%) reacted to OFC. However, among patients with definitive BW allergies (n = 50) who underwent OFCs a median of 7.0 years after their last immediate reaction, 14 (28.0%) reacted to OFC. Among 12 patients with past anaphylactic reactions to BW, 8 exhibited tolerance to BW. A history of immediate reaction to BW and high BW-specific IgE levels were significant risk factors for a positive OFC. Conclusions: BW allergies are rare among children suspected of having BW allergies due to positivity for BW-specific IgE. Most children with definitive BW allergies can tolerate BW, even after anaphylactic reactions. Nevertheless, careful observation is needed when performing BW OFCs, considering the high incidence of anaphylactic reactions.

Evaluation and characterization of 125 patients with a history of reaction to beta-lactams

Reactions to beta-lactams are frequent and it is difficult to establish the relationship between the drug and symptoms. To describe the clinical characteristics and explore the immunological mechanisms of patients with suspected adverse reaction to beta-lactams. Retrospective study of patients with a history of beta-lactam reaction and tests for reactions to drugs. Out of 125 patients, 71 were women (56.8%); 73 had a history of immediate reaction and 52 delayed reaction; 590 allergy tests were done: specific IgE measurement, skin prick, patch, and provocation tests. The drugs most often related were amoxycillin, in 62 patients (49.6%), crystalline penicillin in 17 (13.6%), benzathine penicillin in 15 (12%), and cefalexin in 13 (10.4%). The severity of the reaction was mild in the majority (82%). 7.7% had a history of anaphylaxis and 10.8% sought care for a positive penicillin skin test, without history of reaction. Only 6.7% resulted in a positive test. More than 62% began testing two years after the reaction for which they sought care. The clinical history is insufficient to determine allergy to beta-lactams. In our sample, few patients with a history of beta-lactam reaction had evidence of immune-mediated reactions.

Asymptomatic LTP sensitisation is common in plant-food allergic children from the Northeast of Spain

BackgroundThe sensitisation profile at molecular level in plant-food allergy is complex. Several allergens may be involved, with different potential for severe reactions. lipid transfer proteins (LTP) are considered the most relevant plant-food allergens in adults in Mediterranean countries, but less is known in children. AimTo describe the clinical pattern and sensitisation profile of children with plant-food allergy and LTP sensitisation from Northeast Spain. MethodsChildren with history of immediate reaction to plant-food(s), positive skin-prick-test to the culprit plant-food(s) and specific-IgE to plant-food LTPs were analysed. Results130 children were included. 69.2% (90/130) had reacted to ≥2 taxonomically unrelated plant-foods. Peach, walnut, hazelnut and peanut were most frequently involved. Reactions severity ranged from anaphylaxis (45.4%, 59/130) to oral symptoms only. Sensitisation to a particular plant-food LTP not always caused clinical symptoms with that plant-food; 69% (40/58) and 63% (17/27) of peach- and walnut-tolerant subjects had positive rPru p 3 and nJug r 3 specific IgE, respectively. 65.4% (85/130) of children were also sensitised to storage proteins, which was associated to anaphylaxis and nut allergy. However, 60% of patients without nuts/seeds allergy were sensitised to storage proteins. Specific-IgE levels to LTPs and/or storage proteins were not useful to predict allergy (vs. tolerance) to peach, walnut, peanut or hazelnut. ConclusionsSensitisation to LTP and/or storage proteins without clear clinical significance is relatively common. Prospective longitudinal studies are required to evaluate the relevance of these silent sensitisations over time. Caution is required when interpreting the results of molecular-based diagnostic tools in clinical practice.

Age of resolution from IgE-mediated wheat allergy.

The natural history of wheat allergy varies among different countries. To study the age of resolution from IgE-mediated wheat allergy and to define the predictors of wheat tolerance. Patients with a history of immediate reactions after wheat ingestion were enrolled. Skin prick test (SPT) and measurement of serum specific IgE (sIgE) to wheat and ω-5 gliadin were performed. Oral challenge to wheat was performed to determine wheat tolerance. Fifty-five patients, aged 6 months to 12 years, were studied. The median age of wheat tolerance was 76 months (range 37-114 months). The percentage of children with wheat tolerance was 14.7% at age 2 years, 27% by age 4, 45.7% by age 5 and 69% by age 9. Predictors for wheat tolerance were SPT for wheat less than 3 mm of wheal diameter (hazard ratio 8.9), sIgE levels of wheat and ?-5 gliadin less than 0.35 (HR 4.3) and 0.35 kAU/L (HR 44), respectively, duration of onset of symptoms to time of physician diagnosis less than 36 months (HR 7.6) and no history of allergic rhinitis (HR 4.8). Forty percent of children with IgE-mediated wheat allergy develop tolerance by the age of 5 years. Size of SPT, IgE level of wheat and ω-5 gliadin, time from onset of symptoms to physician diagnosis and history of allergic rhinitis are helpful for predicting wheat tolerance.

Natural History of Food-Triggered Atopic Dermatitis and Development of Immediate Reactions in Children

Case reports suggest that children with food-triggered atopic dermatitis (AD) on elimination diets may develop immediate reactions on accidental ingestion or reintroduction of an avoided food. The objective of this study was to systematically study the incidence and risk factors associated with these immediate reactions. A retrospective chart review of 298 patients presenting to a tertiary-care allergy-immunology clinic based on concern for food-triggered AD was performed. Data regarding triggering foods, laboratory testing, and clinical reactions were collected prospectively from the initial visit. Food-triggered AD was diagnosed by an allergist-immunologist with clinical evaluation and laboratory testing. We identified immediate reactions as any reaction to a food for which there was evidence of sIgE and for which patients developed timely allergic signs and symptoms. Differences between children with and without new immediate reactions were determined by a Mann-Whitney, χ(2), or Fisher's exact test as appropriate. A total of 19% of patients with food-triggered AD and no previous history of immediate reactions developed new immediate food reactions after initiation of an elimination diet. Seventy percent of reactions were cutaneous but 30% were anaphylaxis. Cow's milk and egg were the most common foods causing immediate-type reactions. Avoidance of a food was associated with increased risk of developing immediate reactions to that food (P < .01). Risk was not related to specific IgE level nor a specific food. A significant number of patients with food-triggered AD may develop immediate-type reactions. Strict elimination diets need to be thoughtfully prescribed as they may lead to decreased oral tolerance.