Predicting the Outcome of the Buckwheat Oral Challenge Test: A First Evaluation Assuming a Single Serving of Boiled Buckwheat Noodles.

Summary: Background. Global increase in buckwheat consumption has led to a surge in buckwheat allergy reports. However, studies scrutinizing the predictive accuracy of buckwheat-specific immunoglobulin E (IgE) antibody levels in correlation with symptom manifestation remain limited. A critical concern is the discrepancy between the total buckwheat amount featured in prior studies and the quantity consumed per occasion. We aimed to determine open Oral Food Challenge (OFC) positivity rates with buckwheat, using a single serving of boiled buckwheat noodles, and assess the predictability of positive responses using buckwheat-specific IgE levels. Methods. Patients aged 20 years or younger, suspected of buckwheat allergy, were subjected to an OFC involving consumption of 100 g (4800 mg of protein) of boiled buckwheat noodles for those under six years, and 200 g (9600 mg of protein) for those six years or older. The predictive accuracy of the OFC, corresponding with buckwheat-specific IgE antibody levels, was evaluated using Receiver Operating Characteristic (ROC) analysis. Results. Our study involved 80 patients who undertook a buckwheat OFC. Among these, 14 (17.5%) tested positive for a buckwheat allergy, with 3 (3.8%) developing anaphylaxis. The comparative analysis of buckwheat-specific IgE antibody levels did not offer a reliable predictive measure for OFC outcomes. However, a past history of symptom manifestation following buckwheat consumption was significantly correlated with a positive OFC. Conclusions. Forecasting OFC outcomes based on buckwheat-specific IgE antibody levels poses a challenge, even when taking into account the total quantity of buckwheat that can be consumed in a single occasion.

World Allergy Organization (WAO) Diagnosis and Rationale for Action against Cow's Milk Allergy (DRACMA) Guideline update - VII - Milk elimination and reintroduction in the diagnostic process of cow's milk allergy.

The diagnosis of cow's milk allergy (CMA) in infants and young children remains a challenge because many of the presenting symptoms are similar to those experienced in other diagnoses. Both over- and under-diagnosis occur frequently. Misdiagnosis carries allergic and nutritional risks, including acute reactions, growth faltering, micronutrient deficiencies and a diminished quality of life for infants and caregivers. An inappropriate diagnosis may also add a financial burden on families and on the healthcare system. Elimination and reintroduction of cow's milk (CM) and its derivatives is essential for diagnosing CMA as well as inducing tolerance to CM. In non-IgE mediated CMA, the diagnostic elimination diet typically requires 2-4 weeks before reintroduction, while for IgE mediated allergy the time window may be shorter (1-2 weeks). An oral food challenge (OFC) under medical supervision remains the most reliable diagnostic method for IgE mediated and more severe types of non-IgE mediated CMA such as food protein induced enterocolitis syndrome (FPIES). Conversely, for other forms of non-IgE mediated CMA, reintroduction can be performed at home. The OFC cannot be replaced by the milk ladder after a diagnostic elimination diet. The duration of the therapeutic elimination diet, once a diagnosis was confirmed, can only be established through testing changes in sensitization status, OFCs or home reintroduction, which are directed by local protocols and services' availability. Prior non-evidence-based recommendations suggest that the first therapeutic elimination diet should last for at least 6 months or up to the age of 9-12 months, whichever is reached first. After a therapeutic elimination diet, a milk-ladder approach can be used for non-IgE mediated allergies to determine tolerance. Whilst some centers use the milk ladder also for IgE mediated allergies, there are concerns about the risk of having immediate-type reactions at home. Milk ladders have been adapted to local dietary habits, and typically start with small amounts of baked milk which then step up in the ladder to less heated and fermented foods, increasing the allergenicity. This publication aims to narratively review the risks associated with under- and over-diagnosis of CMA, therefore stressing the necessity of an appropriate diagnosis and management.

Low-Dose Oral Challenge Test in Pediatric Patients With Peanut Allergy: Tolerance Assessment of a Trace 5 mg Peanut Test After Symptom Induction With a 500 mg Test.

Introduction Peanut allergy (PA) represents a significant public health concern, particularly prevalent in Western countries. Children at high risk for PA may undergo a low-dose oral food challenge (OFC). However, if the result is positive, complete elimination of peanuts from the diet is recommended, and further trace OFC is typically not performed.  Material and methods This cross-sectional study retrospectively examined the rate of positive peanut OFC with a total peanut load of 5 mg in children who tested positive with a total peanut load of 500 mg. Patient information was gathered from medical records. The primary endpoint was the rate at which children who tested positive in the OFC with 500 mg of peanut butter also tested positive with 5 mg of peanut butter equivalent.  Results Among 32 children who underwent an OFC with a total peanut load of 500 mg, two were excluded for not meeting the criteria. Among the remaining 30 children, 14 (46.7%) had a positive 500 mg peanut OFC test, and three (10%) experienced an anaphylactic reaction. Those who tested positive for the OFC had higher peanut-specific and Ara h2-specific immunoglobulin E (IgE) antibodies. An OFC with 5 mg of peanuts performed on 10 of the 14 patients who tested positive for 500 mg of peanuts showed no positive results. Conclusion The results of this study suggest that children with severe PA who exhibit positive symptoms to a total peanut load of 500 mg can tolerate a 5 mg dose of peanuts and should be considered for an OFC.

Risk Factors of Challenge-Proven Beta-Lactam Allergy in Children with Immediate and Non-Immediate Mild Cutaneous Reactions.

INTRODUCTION: Beta-lactam (BL) antibiotics are the most often involved drugs in allergic reactions. Mild cutaneous reactions such as maculopapular exanthema or urticaria are the most common presenting complaints of BL allergy in the pediatric population. However, it can be challenging to distinguish BL-induced allergy from reactions due to infections or other reasons. In this study, we aimed to determine the clinical characteristics and potential risk factors of true BL allergy in children with suspected mild cutaneous reactions to BLs. METHODS: We evaluated children who were admitted to our pediatric allergy clinic with suspected BL allergy in between January 2015 and March 2020. Patients with a history suggestive of immediate and non-immediate mild cutaneous reactions were included in the study. The oral challenge test (OCT) with the culprit drug was performed on all patients to confirm the diagnosis. RESULTS: Two hundred fourteen (119 male and 95 female) patients with a median age of 4.9 years were evaluated. BL allergy was confirmed in 10.7% (23) of the patients, according to the OCT results. Most of the proven allergic reactions were of the immediate type (73.9%), and urticaria was the most common presenting complaint (60.8%) in proven BL-allergic patients. The negative predictive value of penicillin-G skin testing was 89.7% for immediate-type penicillin allergy and 93.4% for non-immediate reactions. Also, positive predictive value of penicillin-G skin testing was 50% for immediate and 25% for non-immediate reactions. In the multivariate logistic regression analysis, a history of proven drug allergy (Exp (B): 7.76, 95% CI: 1.88-31.97, p = 0.005) was found to be the risk for BL allergy. CONCLUSION: This study highlighted that OCTs should be performed to confirm the diagnosis in patients suspected of immediate and non-immediate mild cutaneous reactions to BLs and remove the overestimated "BL allergy" label. In these patients, a history of proven drug allergy might be a risk factor for true BL allergy.

Behind the scene: Paracetamol hypersensitivity in children.

BACKGROUND: Paracetamol, a non-steroidal anti-inflammatory drug, is commonly being used for fever and pain relief worldwide. The aim of this study was to evaluate children with a suspected history of paracetamol hypersensitivity. METHODS: Sixty patients who were referred to our clinic in between January 2015 and December 2018 with a suspected history of paracetamol hypersensitivity were included. Reactions were classified according to the European Network for Drug Allergy (ENDA)/Global Allergy and Asthma European Network classification and European Academy of Allergy and Clinical Immunology (EAACI)/ENDA Position Paper. Diagnoses were confirmed by skin tests and oral challenge tests (OCTs). In those with verified paracetamol hypersensitivity, an OCT with a strong COX-1 inhibitor was performed to classify the type of the reaction to refer as either selective or cross-intolerance hypersensitivity. A subsequent OCT with a selective COX-2 inhibitor was performed in those cross-intolerant patients to find out a safe alternative drug. RESULTS: Sixty OCTs with paracetamol were performed to patients with a median age of 8.5 years, and hypersensitivity to paracetamol was verified in 8 patients. Four children were classified as selective responders, and 3 were classified as cross-intolerant after OCT with a COX-1 inhibitor. Overall, skin test positivity for paracetamol was detected in only one patient, in whom OCT with paracetamol was negative. In all 3 cross-intolerant patients, a safe alternative non-steroidal anti-inflammatory drug was identified after an OCT with a selective COX-2 inhibitor. CONCLUSION: OCT stands as the gold-standard procedure in verifying the diagnosis of patients with paracetamol-induced drug hypersensitivity, as well as, in defining the type of reactions and finding out safe alternative drugs.

A Cross-Sectional Observational Study of Clinical Spectrum and Prevalence of Fixed Food Eruption in a Tertiary Care Hospital.

BACKGROUND: Fixed food eruption (FFE) is a rare type of hypersensitivity reaction occurring after ingestion of some food items in the form of recurrent erythematous patches, bullae, vesicle, or pustule at the same site after ingestion of same or related food products. Various items listed responsible for causing FFE include tree nuts, groundnuts, legumes, lentils, eggs, fruits like kiwi, strawberry, tonic water, and tartrazine. Its more commonly reported in developed countries with no Indian studies as of yet. We studied the clinical spectrum and prevalence of FFE in a tertiary care hospital. OBJECTIVE: To study the prevalence and pattern of FFE after eliminating all other possible causes including drug rash. MATERIALS AND METHODS: A cross-section observational study of 27 consecutive patients suspected to have fixed food eruption after eliminating all possibilities of any drug reaction to the best of our knowledge. Informed consent was obtained from the patients, and ethical clearance was taken from the hospital ethical committee. RESULTS: A total of 27 patients were studied out of which 18 (66.66%) were females and 9 (33.33%) were males. The prevalence of fixed food eruption was calculated to be 0.072%.Fixed food eruption was noted secondary to cashew nuts (14.8%), almonds (7.4%), walnut (7.4%), pistachio (3.7%), strawberry (3.7%), kiwi (3.7%), and cheese crisps (3.7%). CONCLUSION: This observational study highlights the varied patterns of fixed food eruptions as well as the burden of disease in population secondary to certain diets.

Long-Term Follow-Up After Penicillin Allergy Delabeling in Ambulatory Patients.

BACKGROUND: Unverified penicillin allergy label has negative health implications. To address this, several delabeling methods have been proposed. OBJECTIVES: To appraise the long-term outcomes of the penicillin allergy evaluation in ambulatory patients, focusing on subsequent use of penicillins in individuals found not allergic. A secondary objective was to examine the consistency between the evaluation's recommendations and the allergy label. METHODS: A retrospective medical records review and phone survey were carried out in ambulatory patients who were evaluated for suspected penicillin allergy in our allergy unit. Patients with an uneventful oral challenge test (OCT) were interviewed regarding subsequent use of penicillins. Medical records were examined for antibiotic prescriptions and purchases. The records were also investigated for existing/erased penicillin allergy label and its consistency with the allergy evaluation. RESULTS: Six hundred thirty-nine patients with an uneventful OCT were available for the survey. During a 56-month follow-up, 70% (447 patients) had used penicillins at least once. One hundred ninety-two patients (30%) did not use penicillins. The main reason for not using penicillins was lack of a clinical indication. Three hundred thirty-five patients (51.22%) carried a penicillin allergy label in their electronic medical file in spite of an uneventful OCT. CONCLUSIONS: Penicillin allergy annulling via OCT has proven to be effective. Most of the patients who previously avoided penicillins have reused penicillins safely.

Flare-Up Phenomenon of Intradermal Test with Anaphylactic Reaction to Paracetamol (Acetaminophen).

BACKGROUND: Paracetamol is a Non-Steroidal Anti-Inflammatory Drug (NSAID) that can produce hypersensitive reactions mediated by specific immunological mechanisms (IgE or T celldependent) or by a non-immunological mechanism (inhibition of cyclooxygenase COX-1). OBJECTIVE: An 80-year-old man with a history of allergy to pyrazolones, with good tolerance to other NSAIDs was referred to our allergy department because he presented a generalized urticaria after the administration of Intravenous (IV) paracetamol. METHODS: We performed an Intradermal Test (IDT) with paracetamol (0.02mg/ml) and later a Single Blind Oral Challenge Test (SBOCT) with oral paracetamol. RESULTS: IDT reading at 15min showed negative result so an SBOCT was performed with oral paracetamol. With an accumulative dose of 250mg, after 20min, he developed discomfort, nausea and dizziness, urticarial, hypotension (BP 80/40) as well as flare-up phenomenon was observed in the site of the IDT with paracetamol. Tryptase levels during the reaction and 2hrs later were increased. CONCLUSION: We present an anaphylactic shock due to sensitization to paracetamol because of a type I hypersensitivity mechanism, diagnosed by SBOCT and a positive IDT because of flare-up phenomenon, in a patient with previous pyrazolones allergy and with tolerance to other NSAIDs. Some relevant patents are also summarized in this paper.

[Fixed drug eruption to clarithromycin: The importance of challenge tests in diagnosis]. / Érythème pigmenté fixe à la clarithromycine : importance des tests de provocation pour le diagnostic.

BACKGROUND: Determining the substance responsible for recurrent fixed drug eruption (FDE) may be difficult in the case of patients on multiple medication. Allergy testing may prove invaluable in such situations, as we demonstrate herein with an original case. PATIENTS AND METHODS: A 49-year-old man presented a rash on the seventh day of treatment with esomeprazole, clarithromycin and amoxicillin prescribed for gastritis involving Helicobacter pylori. The condition regressed spontaneously within a few days, but left three areas of hyperpigmentation. The patient subsequently reported four further episodes consisting of stereotypical reactivation in the areas of the three initial lesions and occurring 24hours after use of clarithromycin (2 episodes) and amoxicillin (2 episodes). The patient resumed proton pump inhibitor therapy (esomeprazole) without incident. Based on history taking, an initial diagnosis was made of multiple fixed drug eruption involving amoxicillin and clarithromycin. The initial skin allergy investigations were negative (patch-tests for amoxicillin and clarithromycin on healthy skin on the patient's back and on the affected area). After discussion, we decided to reintroduce the suspected drugs in succession. Beginning with clarithromycin, 12h after a single dose of 250mg, we noted an erythematous reaction on the pigmented areas, together with a burning sensation. In an identical challenge test with amoxicillin (500mg), the latter drug was perfectly well tolerated, ruling out the diagnosis of FDE to amoxicillin and thus the diagnosis of multiple FDE suggested by the patient history. DISCUSSION: FDEs to macrolides are rare, and herein we report a new case. Our observation confirms the diagnostic value of challenge tests in FDE. These tests should only be performed in the event of non-severe FDE, in other words not in bullous or systemic reactions, and they often constitute the only diagnostic approach possible, since skin tests are rarely positive during investigation for FDE.

An oral challenge test with carmine red (E120) in skin prick test positive patients.

BACKGROUND: Positive skin prick test reactions to carmine red (E120) occur in approximately 3% of the patients studied for food allergy. Carmine ingestion associated systemic symptoms are occasionally suspected, but sufficient information of proven carmine allergy is not available. PATIENTS AND METHODS: To analyse carmine related symptoms in skin prick test positive patients a cohort of 23 patients with suspected allergy to carmine red was subjected to a single-blind placebo-controlled oral challenge test with carmine red. RESULTS: Five patients developed clinical symptoms during the placebo-controlled oral challenge. As a result, the overall frequency of clinical carmine allergy is estimated to be 0.7% in general dermatology patients studied for food-associated symptoms. CONCLUSIONS: Oral challenge test provides a valuable in vivo tool to better inform patients with positive skin prick tests to additives to avoid false allergy diets.

Immediate-type hypersensitivity reaction to Mannitol as drug excipient (E421): a case report.

Allergic reactions to mannitol have been reported rarely, despite its widespread use as a drug and as a food excipient. This is the first case report in which oral mannitol induces an immediate type hypersensitivity as a drug excipient, in a 42 year old man affected by rhinitis to olive tree pollen. Unusual and undervalued risk factors for mannitol hypersensitivity are examined.

Using a gluten oral food challenge protocol to improve diagnosis of wheat-dependent exercise-induced anaphylaxis.

BACKGROUND: Oral wheat plus cofactors challenge tests in patients with wheat-dependent exercise-induced anaphylaxis (WDEIA) produce unreliable results. OBJECTIVE: We sought to confirm WDEIA diagnosis by using oral gluten flour plus cofactors challenge, to determine the amount of gluten required to elicit symptoms, and to correlate these results with plasma gliadin levels, gastrointestinal permeability, and allergologic parameters. METHODS: Sixteen of 34 patients with a history of WDEIA and ω5-gliadin IgE underwent prospective oral challenge tests with gluten with or without cofactors until objective symptoms developed. Gluten reaction threshold levels, plasma gliadin concentrations, gastrointestinal permeability, sensitivities and specificities for skin prick tests, and specific IgE levels were ascertained in patients and 38 control subjects. RESULTS: In 16 of 16 patients (8 female and 8 male patients; age, 23-76 years), WDEIA was confirmed by challenges with gluten alone (n = 4) or gluten plus cofactors (n = 12), including 4 patients with previous negative wheat challenge results. Higher gluten doses or acetylsalicylic acid (ASA) plus alcohol instead of physical exercise were cofactors in 2 retested patients. The cofactors ASA plus alcohol and exercise increased plasma gliadin levels (P < .03). Positive challenge results developed after a variable period of time at peak or when the plateau plasma gliadin level was attained. Positive plasma gliadin threshold levels differed by greater than 100-fold and ranged from 15 to 2111 pg/mL (median, 628 pg/mL). The clinical history, IgE gliadin level, and baseline gastrointestinal level were not predictive of the outcomes of the challenge tests. The challenge-confirmed sensitivity and specificity of gluten skin prick tests was 100% and 96%, respectively. CONCLUSION: Oral challenge with gluten alone or along with ASA and alcohol is a sensitive and specific test for the diagnosis of WDEIA. Exercise is not an essential trigger for the onset of symptoms in patients with WDEIA.

Benefits and limitations of molecular diagnostics in peanut allergy: Part 14 of the series Molecular Allergology.

Allergic reactions to peanut (Arachis hypogaea, Ara h) are caused by immunoglobulin E (IgE)-mediated sensitizations to various proteins. The stability and relative proportion of these proteins in peanut determine the risk of hazardous reactions. Hazardous sensitization to seed storage proteins [S2 albumins (Ara h 2, 6 and 7) > other seed storage proteins (Ara 1 and 3) > oleosins (Ara h 10 and 11)] are distinct from sensitizations to lipid transfer protein (Ara h 9) with moderate risk or cross-sensitizations to Bet v 1-homologous PR-10 protein (Ara h 8) and to profilin (Ara h 5) with low risk. A specific IgE test, e.g. to Ara h 2 in the case of suspected systemic reaction, or where this should be ruled out, can facilitate easier risk assessment. Results, however, are only relevant in the presence of corresponding clinical symptoms. IgE sensitization to peanut extract without hazardous reactions is often caused in this part of the world by Bet v 1-related cross reactions (in birch pollen allergy sufferers), cross-reactive carbohydrate determinants (CCD) or profilin sensitizations. In the case of doubt, clinical relevance can only be established by means of oral challenge, particularly since not all peanut allergens (e. g., oleosins) are available as yet for diagnostic purposes.

A case of anaphylaxis to oral minocycline.

Minocycline is a semisynthetic tetracycline derivative that is often used in the treatment of acne vulgaris. To date, there has been only one case report of anaphylaxis to minocycline. We report here a case of anaphylaxis to oral minocycline. A 56-yr-old woman visited our hospital after three episodes of recurrent anaphylaxis. We performed an oral challenge test, the standard method for diagnosing drug allergies, with minocycline, one of the drugs she had taken previously. She developed urticaria, angioedema, nausea, vomiting, hypotension, and dyspnea within 4 min and was treated with intramuscular epinephrine, intravenous antihistamine and systemic corticosteroid. However, she presented similar symptoms at 50 min and at 110 min. In prescribing oral minocycline, physicians should consider the possibility of serious adverse reactions, such as anaphylaxis.

A Case of Anaphylaxis to Oral Minocycline

Minocycline is a semisynthetic tetracycline derivative that is often used in the treatment of acne vulgaris. To date, there has been only one case report of anaphylaxis to minocycline. We report here a case of anaphylaxis to oral minocycline. A 56-yr-old woman visited our hospital after three episodes of recurrent anaphylaxis. We performed an oral challenge test, the standard method for diagnosing drug allergies, with minocycline, one of the drugs she had taken previously. She developed urticaria, angioedema, nausea, vomiting, hypotension, and dyspnea within 4 min and was treated with intramuscular epinephrine, intravenous antihistamine and systemic corticosteroid. However, she presented similar symptoms at 50 min and at 110 min. In prescribing oral minocycline, physicians should consider the possibility of serious adverse reactions, such as anaphylaxis.