Diagnosis Of IgE-mediated Food Allergy Research Articles

Interpretation of 2023 EAACI guidelines on the diagnosis of IgE-mediated food allergy

The prevalence of food allergy is increasing globally, becoming a significant public health issue that greatly impacts the quality of life for patients and their families. However, there is currently a problem with both underdiagnosis and overdiagnosis of food allergy. Therefore, accurate diagnosis of food allergy and personalized management based on accurate diagnosis are crucial. Over the past 10 years, there has been relevant research on food allergy diagnosis, particularly focusing on IgE-mediated food allergy diagnostic methods such as component resolved diagnosis and basophil activation test, since the launch of the European Academy of Allergy and Clinical Immunology(EAACI) Food Allergy Guidelines in 2014. In October 2023, EAACI published updated diagnostic guidelines for IgE-mediated food allergy. To help allergists and other medical professionals stay informed about the latest EAACI recommendations on the diagnosis of IgE-mediated food allergy, this guideline is now being interpreted.

EAACI guidelines on the diagnosis of IgE-mediated food allergy.

This European Academy of Allergy and Clinical Immunology guideline provides recommendations for diagnosing IgE-mediated food allergy and was developed using the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) approach. Food allergy diagnosis starts with an allergy-focused clinical history followed by tests to determine IgE sensitization, such as serum allergen-specific IgE (sIgE) and skin prick test (SPT), and the basophil activation test (BAT), if available. Evidence for IgE sensitization should be sought for any suspected foods. The diagnosis of allergy to some foods, such as peanut and cashew nut, is well supported by SPT and serum sIgE, whereas there are less data and the performance of these tests is poorer for other foods, such as wheat and soya. The measurement of sIgE to allergen components such as Ara h 2 from peanut, Cor a 14 from hazelnut and Ana o 3 from cashew can be useful to further support the diagnosis, especially in pollen-sensitized individuals. BAT to peanut and sesame can be used additionally. The reference standard for food allergy diagnosis is the oral food challenge (OFC). OFC should be performed in equivocal cases. For practical reasons, open challenges are suitable in most cases. Reassessment of food allergic children with allergy tests and/or OFCs periodically over time will enable reintroduction of food into the diet in the case of spontaneous acquisition of oral tolerance.

Food allergy-A holistic approach to dietary management. A joint EAACI Research & Outreach Committee and INDANA review.

Following a diagnosis of IgE-mediated food allergy, to secure the best outcome, the patient should receive individualized advice tailored to their specific needs, which considers the type and presentation of the food involved, level of exclusion required, risk of cross-contamination and any variance required for age, ethnicity, financial issues, and lifestyle. Issues such as food labels "may contain" statements, and variation in the threshold of reaction and impact of cofactors should also be considered. Most important is the need to ensure that the diagnosis is robust, especially given the nutritional, psychological, and socioeconomic issues that can affect an individual with a diagnosis of food allergy. Unnecessary exclusion of one or more foods that have not triggered allergic reactions, especially in individuals with allergic comorbidities, can result in severe IgE-mediated reactions on re-exposure. Given that food allergies may change over time, the diagnosis should be reviewed, to determine whether resolution is likely, or new-food triggers are reported. Regular assessment is vital, especially during childhood, to ensure reintroduction occurs at an appropriate time, thus enabling increased diversity of the diet and improvement in the quality of life. For some, an IgE-mediated food allergy may necessitate the life-long exclusion of foods, and for others, a food habitually eaten suddenly triggers an allergic reaction in adult life. People of all ages, ethnicities, and socioeconomic backgrounds deserve individual advice on the management of their food allergy to support a healthy diet and improve quality of life.

Is it possible to predict the development of anaphylaxis before oral food challenge tests administered to evaluate tolerance in IgE-mediated food allergy in children?

Objective: Life-threatening anaphylaxis may occur in IgE-mediated food allergy. Oral Food Challenge (OFC) is the gold standard in demonstrating tolerance and diagnosing food allergy; however, these tests may cause anaphylaxis. Predicting the risk of developing anaphylaxis before performing OFC is valuable information in evaluating tolerance as in diagnosis. The present study aims to evaluate the effectiveness of the tests used in clinical practice in predicting the risk of anaphylaxis during OFC in IgE-mediated food allergy. To our knowledge, this is the first study evaluating skin prick tests in the prediction of anaphylaxis. Material and Methods: In this descriptive cross-sectional study, the history, demographic, clinical and laboratory data of the patients, followed up with the diagnosis of IgE-mediated food allergy, on whom OFC was performed, were evaluated retrospectively. Results: Of the 254 patients who underwent OFC, 133 were followed up with a diagnosis of IgE-mediated food allergy. The mean age was 21 months (12-120), and anaphylaxis occurred in nine (6.7%) of them during OFC. According to the frequency, the food responsible for IgE-mediated food allergy was determined as milk, egg and egg-milk combination. Age during the challenge and total IgE levels were higher in the group that experienced OFC-related anaphylaxis. The tests that could best determine the risk of anaphylaxis before the challenge was the skin prick test (SPT) and prick to prick (PTP) test for milk. Milk SPT and PTP test at the time of initial diagnosis and determination of milk sIgE and egg white sIgE before challenge were found to predict the risk of anaphylaxis. The negative predictive value was over 95% in tests that gave significant results for milk. There was no statistically significant finding associated with other allergenic foods. Conclusion: In evaluating tolerance development, performing sIgE, SPT and/or PTP tests for milk before OFC is useful in predicting anaphylaxis. Studies with larger numbers of cases are needed to assess the risk of anaphylaxis caused by other foods.

Homemade Food Allergen Extracts for Use in Skin Prick Tests in the Diagnosis of IgE-Mediated Food Allergy: A Good Alternative in the Absence of Commercially Available Extracts?

Introduction: The skin prick test (SPT) is the first step in the diagnosis of an immunoglobulin E (IgE)-mediated food allergy. The availability of commercial food allergen extracts is very limited, resulting in a need for alternative extraction methods of food allergens. The objective of this study was to compare the SPT results of homemade food allergen extracts with commercially available extracts. Methods: Adult patients with a suspected food allergy were included. Food allergen-specific symptoms were scored using a questionnaire. SPTs were performed with homemade and commercially available extracts (ALK-Abelló, Kopenhagen, Denmark) from almond, apple, hazelnut, peach, peanut, and walnut. Serum-specific IgE was measured with ISAC or ImmunoCAP™. Intra-class correlation coefficients (ICC) between the SPT results of both extract methods were calculated. The proportion of agreement with food allergen-specific symptoms was analyzed. Results: Fifty-four patients (mean age 36; range 19–69 years; female/male: 42/12) were included. The intra-class correlation coefficient (ICC) between the SPT results of both extract methods were strong for hazelnut 0.79 (n = 44) and walnut 0.78 (n = 31), moderate for apple 0.74 (n = 21) and peanut 0.66 (n = 28), and weak for almond 0.36 (n = 27) and peach 0.17 (n = 23). The proportion of agreement between SPT results and food allergen-specific symptoms was comparable for homemade and commercially available extracts, except for peach; 0.77 versus 0.36, respectively. Conclusion: In the diagnostic procedures to identify an IgE-mediated food allergy, homemade extracts from hazelnut and walnut appear to be a good alternative in the absence of commercially available food allergen extracts.

Facteurs de risque et évolution des allergies alimentaires IgE médiées avant et après transplantation hépatique dans une cohorte pédiatrique française

IntroductionAfter liver transplantation (LT), children treated with tacrolimus may develop IgE-mediated food allergy (IMFA). MethodLT children were referred by hepatologists to an allergist for suspected IMFA. An allergological evaluation before and after LT was performed. The results of the data were compared. ResultsThe cohort included 30 children with a mean age of 2.8 years, all treated with basiliximab and tacrolimus combo in post-LT. For 10 children, the clinical history and/or skin and biological tests and/or oral challenge test could rule out the diagnosis of IMFA. The diagnosis of IMFA was confirmed in 20 children (67%), of whom 70% (n=14) had familial atopy. Thirteen children were switched from tacrolimus to cyclosporine, of whom 3 were cured and 6 had persistent allergy. Children with post-LT sensitization presented IMFA (n=13, 76%) of which 54% (n=7) healed spontaneously. Children with pre- and post-LT sensitization had IMFA in 63% (n=7). Only 29% of them (n=2) recovered. For 71% (n=5) of them, the allergy persisted. The most frequently incriminated food allergens were, in decreasing order, peas, fish, lentils, peanuts and eggs. ConclusionChildren sensitized in pre- and post-LT settings have mostly persistent IMFA, whereas those with sensitization that appeared in post-LT tend to become tolerant spontaneously. Long-term follow-up in collaboration between hepatologist and allergist is essential.

Whole-cell pertussis vaccine in early infancy for the prevention of allergy in children.

Atopic diseases are the most common chronic conditions of childhood. The apparent rise in food anaphylaxis in young children over the past three decades is of particular concern, owing to the lack of proven prevention strategies other than the timely introduction of peanut and egg. Due to reported in vitro differences in the immune response of young infants primed with whole-cell pertussis (wP) versus acellular pertussis (aP) vaccine, we systematically appraised and synthesised evidence on the safety and the potential allergy preventive benefits of wP, to inform recommendation for future practice and research. To assess the efficacy and safety of wP vaccinations in comparison to aP vaccinations in early infancy for the prevention of atopic diseases in children. We searched the Cochrane Central Register of Controlled Trials, Ovid MEDLINE, Embase, and grey literature. The date of the search was 7 September 2020. We included randomised controlled trials (RCTs) and non-randomised studies of interventions (NRSIs) that reported the occurrence of atopic diseases, and RCTs only to assess safety outcomes. To be included studies had to have at least six months follow-up, andinvolve children under 18 years old, who received a first dose of either wP (experimental intervention) or aP (comparator) before six months of age. Two review authors independently screened studies for eligibility, extracted the data, and assessed risk of bias using standard Cochrane methods. We assessed the certainty of the evidence using GRADE. Our primary outcomes were diagnosis of IgE-mediated food allergy and all-cause serious adverse events (SAEs). Secondary outcomes included: diagnosis of not vaccine-associated anaphylaxis or urticaria, diagnosis of asthma, diagnosis of allergic rhinitis,diagnosis of atopic dermatitis and diagnosis of encephalopathy. Due to paucity of RCTs reporting on the atopic outcomes of interest, we assessed a broader outcome domain (cumulative incidence of atopic disease) as specified in our protocol.We summarised effect estimates as risk ratios (RR) and 95% confidence intervals (CI). Where appropriate, we pooled safety data in meta-analyses using fixed-effect Mantel-Haenszel methods, without zero-cell corrections for dichotomous outcomes. We identified four eligible studies reporting on atopic outcomes, representing 7333 children. Based on a single trial, there was uncertain evidence on whether wP vaccines affected the risk of overall atopic disease (RR 0.85, 95% CI 0.62 to 1.17) or asthma only (RR 1.04, 95% CI 0.59 to 1.82; 497 children) by 2.5 years old.Three NRSIs were judged to be at serious or critical risk of bias due to confounding, missing data, or both, and were ineligible for inclusion in a narrative synthesis. We identified 21 eligible studies (137,281 children) that reported the safety outcomes of interest. We judged seven studies to be at high risk of bias and those remaining, atunclear risk. The pooled RR was 0.94 for all-cause SAEs (95% CI 0.78 to 1.15;I2 = 0%; 15 studies, 38,072children).For every 1000 children primed with a first dose of wP, 11 had an SAE. The corresponding risk with aP was 12 children (95% CI 9 to 13). The 95% CI around the risk difference ranged from three fewer to two more events per 1000 children, and the certainty of the evidence was judged as moderate (downgraded one level for imprecision). No diagnoses of encephalopathy following vaccination were reported (95% CI around the risk difference - 5 to 12 per 100,000 children;seven primary series studies; 115,271 children). The certainty of the evidence was judged as low, since this is a serious condition, and we could not exclude a clinically meaningful difference. There is very low-certainty evidence that a first dose of wP given early in infancy, compared to a first dose of aP, affects the risk of atopic diseases in children. The incidence of all-cause SAEs in wP and aP vaccinees was low, and no cases of encephalopathy were reported. The certainty of the evidence was judged as moderate for all-cause SAEs, and low for encephalopathy. Future studies should use sensitive and specific endpoints of clinical relevance, and should be conducted in settings with high prevalence of IgE-mediated food allergy.Safety endpoints should prioritise common vaccine reactions, parental acceptability, SAEs and their potential relatedness to the dose administered.

Deriving health utility indices from a food allergy quality-of-life questionnaire.

BackgroundThe Food Allergy Quality‐of‐Life Questionnaire‐Parent Form (FAQLQ‐PF) is widely used to assess food allergy–specific health‐related quality of life (FAQL), but cannot be used directly in cost‐utility analyses, which require health state utility (HSU) scores. Currently, limited evidence is available regarding the HSU of food‐allergic children/adolescents. This study aimed to develop mapping algorithms from the FAQLQ‐PF onto HSU scores generated by generic, preference‐based, health‐related quality‐of‐life (HRQL) instruments.MethodsCaregivers of children aged 7 to 17 years with a clinician diagnosis of IgE‐mediated food allergy, recruited via Allergy & Anaphylaxis Australia, completed an online FAQLQ‐PF questionnaire and proxy generic preference‐based pediatric instruments (Assessment of Quality of Life [AQoL]‐6D and Child Health Utility 9D [CHU9D]). Optimal statistical methods were based on series of goodness‐of‐fit statistics.ResultsMean FAQLQ‐PF total score, AQoL‐6D, and CHU9D utility scores of 238 food‐allergic children/adolescents were 3.49 (SD: 1.41), 0.78 (SD: 0.22), and 0.74 (SD: 0.22), respectively. The Spearman correlation coefficients of FAQLQ‐PF with AQoL‐6D and CHU9D were rho = −0.56 and rho = −0.45, respectively. Optimal mapping algorithms were generated from selected FAQLQ‐PF items, mapped onto AQoL‐6D or CHU9D utility scores, with AQoL‐6D demonstrating better performance.ConclusionsThis study generated mapping algorithms to help facilitate the use of FAQLQ‐PF for cost‐utility analyses, which are essential for health economic evaluation. External validation of the reported mapping algorithms is warranted.

Predictive value of the number of adverse reaction episodes for the IgE-mediated food allergy diagnosis

Introduction and objectivesThe reproducibility of the adverse reaction increases the suggestiveness of a history of food allergy. However, the positive predictive value (PPV) of multiple adverse reaction episodes for the diagnosis of IgE-mediated food allergy is not known. This evaluation was the objective of our study. Patients and methodsWe retrospectively studied 180 children with a history of non-anaphylactic adverse reactions after the ingestion of a food. All children had the prick test positive for the offending food and performed the oral food challenge (OFC) within 12 months after the last adverse reaction episode (ARE). We have evaluated whether increasing the number of ARE increased the probability that the OFC would be positive (failed). Results93 patients (52%) presented one ARE, 49 (27%) presented two ARE, 24 (13%) presented three ARE, 14 (8%) patients presented≥four ARE. The OFC was positive in 94/180 (52%). The outcome of the OFC was found to be positively correlated with the number of ARE (OR=1.56; 95% CI=1.16–2.09; p=0.003). A PPV=100% was observed with a number of ARE≥five. ConclusionsThe number of ARE is an important predictor of the diagnosis of food allergy, although less than we would have imagined. The number of ARE could be used to increase the predictability of the diagnostic tests currently in use, to define clinical prediction rules alternative to OFC and easy to use in clinical practice.

IgE-Mediated Food Allergy

Food allergies are defined as adverse immune responses to food proteins that result in typical clinical symptoms involving the dermatologic, respiratory, gastrointestinal, cardiovascular, and/or neurologic systems. IgE-mediated food-allergic disease differs from non-IgE-mediated disease because the pathophysiology results from activation of the immune system, causing a T helper 2 response which results in IgE binding to Fcε receptors on effector cells like mast cells and basophils. The activation of these cells causes release of histamine and other preformed mediators, and rapid symptom onset, in contrast with non-IgE-mediated food allergy which is more delayed in onset. The diagnosis of IgE-mediated food allergy requires a history of classic clinical symptoms and evidence of food-specific IgE by either skin-prick or serum-specific IgE testing. Symptoms of IgE-mediated food allergies range from mild to severe. The severity of symptoms is not predicted by the level of specific IgE or skin test wheal size, but the likelihood of symptom onset is directly related. Diagnosis is excluded when a patient can ingest the suspected food without clinical symptoms and may require an in-office oral food challenge if testing for food-specific IgE by serum or skin testing is negative or low. Anaphylaxis is the most severe form of the clinical manifestation of IgE-mediated food allergy, and injectable epinephrine is the first-line treatment. Management of food allergies requires strict avoidance measures, counseling of the family about constant vigilance, and prompt treatment of allergic reactions with emergency medications. Guidelines have changed recently to include early introduction of peanuts at 4–6 months of life. Early introduction is recommended to prevent the development of peanut allergy. Future treatments for IgE-mediated food allergy evaluated in clinical trials include epicutaneous, sublingual, and oral immunotherapy.

Road map for the clinical application of the basophil activation test in food allergy.

SummaryThe diagnosis of IgE‐mediated food allergy based solely on the clinical history and the documentation of specific IgE to whole allergen extract or single allergens is often ambiguous, requiring oral food challenges (OFCs), with the attendant risk and inconvenience to the patient, to confirm the diagnosis of food allergy. This is a considerable proportion of patients assessed in allergy clinics. The basophil activation test (BAT) has emerged as having superior specificity and comparable sensitivity to diagnose food allergy, when compared with skin prick test and specific IgE. BAT, therefore, may reduce the number of OFC required for accurate diagnosis, particularly positive OFC. BAT can also be used to monitor resolution of food allergy and the clinical response to immunomodulatory treatments. Given the practicalities involved in the performance of BAT, we propose that it can be applied for selected cases where the history, skin prick test and/or specific IgE are not definitive for the diagnosis of food allergy. In the cases that the BAT is positive, food allergy is sufficiently confirmed without OFC; in the cases that BAT is negative or the patient has non‐responder basophils, OFC may still be indicated. However, broad clinical application of BAT demands further standardization of the laboratory procedure and of the flow cytometry data analyses, as well as clinical validation of BAT as a diagnostic test for multiple target allergens and confirmation of its feasibility and cost‐effectiveness in multiple settings.

Making the Most of In Vitro Tests to Diagnose Food Allergy

Various in vitro tests assess different aspects of the underlying immune mechanism of IgE-mediated food allergy. Some can be used for diagnostic purposes; specific IgE to allergen extracts is widely available; specific IgE to allergen components is used in most specialist centers, and the basophil activation test is becoming increasingly used clinically. IgE to allergen peptides, T-cell assays, allergen-specific/total IgE ratios, and allergen-specific IgG4/IgE ratios are currently reserved for research. Different factors can modulate the likelihood of IgE-mediated food allergy of a given allergy test result, namely, the patients' age, ethnicity, previous allergic reaction to the identified food, concomitant atopic conditions, and geographical location, and need to be taken into account when interpreting the allergy test results in the clinic. The importance of the specific food, the clinical resources available, and patient preferences are additional aspects that need to be considered when deciding whether an oral food challenge is required to reach an accurate diagnosis of IgE-mediated food allergy.

Management of food allergy: A survey of Australian paediatricians

The prevalence of Immunoglobulin E (IgE)-mediated food allergy in the developed world is increasing, overwhelming tertiary allergy services. Alternative models of care are required. General paediatricians could provide this care but may require further training to do so. We aimed to determine Australian general paediatricians': (i) knowledge and management of IgE-mediated food allergy; (ii) access to and use of diagnostic services; and (iii) interest in further training. Members of the Australian Paediatric Research Network completed an online survey in 2011/12. A case study elicited paediatrician's knowledge of diagnostic history taking, testing and key management principles. Study-designed questions assessed paediatricians' current practice, access to allergy services and interest in further training. One hundred sixty-eight (43%) of 390 paediatricians responded; 93 paediatricians reported managing food allergy. Diagnostic and management practices varied widely. Paediatricians had high levels of agreement (>90%) for only three of 13 questions pertaining to diagnosis and management. Only 56 (61%) correctly identified that a diagnosis of IgE-mediated food allergy requires a history consistent with a clinical reaction and a positive specific serum IgE antibody or skin prick test result. Reported waiting times for tertiary allergy services ranged from 5.4 (private) to 10.6 months (public). Most (91%) paediatricians expressed interest in further training. General paediatricians would benefit from further training if they are to practice allergy care as their diagnosis and management is often inconsistent with international guidelines. Training could be delivered online to maximise reach and uptake. If effective, such a model could relieve some of the burden experienced by Australian tertiary allergy services.

The Usefulness of Component-Resolved Diagnostics in Food Allergy

The Usefulness of Component-Resolved Diagnostics in Food Allergy

The diagnosis of food allergy: protocol for a systematic review

BackgroundThe literature on diagnostic tests for food allergy currently lacks clear consensus regarding the accuracy and safety of different investigative approaches. The European Academy of Allergy and Clinical Immunology is in the process of developing its Guideline for Food Allergy and Anaphylaxis, and this systematic review is one of seven inter-linked evidence syntheses that are being undertaken in order to provide a state-of-the-art synopsis of the current evidence base in relation to epidemiology, prevention, diagnosis and clinical management, and impact on quality of life, which will be used to inform the formulation of clinical recommendations. The aim of this systematic review will be to assess the diagnostic accuracy of tests aimed at supporting the clinical diagnosis of IgE-mediated food allergy.MethodsThe following databases from inception to September 30, 2012 will be searched for studies of diagnostic tests: Cochrane Library (Wiley&Sons); MEDLINE (OVID); Embase (OVID); CINAHL (Ebscohost); ISI Web of Science (Thomson Web of Knowledge); TRIP Database (web http://www.tripdatabase.com); and Clinicaltrials.gov (NIH web). These database searches will be supplemented by contacting an international panel of experts. Studies evaluating APT, SPT, specific-IgE, and component specific-IgE in participants of any age with suspected food allergy will be included. The reference standard will be DBPCFC in at least 50% of the participants. Studies will be quality assessed by using the QUADAS-2 instrument. We will report summary statistics such as sensitivity, specificity, and/or likelihood ratios. We will use the hierarchical summary ROC (HSROC) model to summarize the accuracy of each test and to compare the accuracy of two or more tests.DiscussionDecisions on which tests to use need to be guided by availability of tests, populations being cared for, risks, financial considerations and test properties. This review will examine papers from around the world, covering children and adults with suspected food allergy in varying populations and concentrated on four type of tests: APT, SPT, specific-IgEs, and component specific-IgEs.

Adverse Food Reactions—An Emerging Issue for Adults

Adverse reactions to foods are classified according to the presence or absence of involvement of the immune system, which may or may not include the production of immunoglobulin E (IgE) antibodies. This review focuses on the epidemiology, diagnosis, and management of adverse food reactions, primarily in adults, and excluding celiac disease and lactose intolerance. Reported reactions to foods are often believed to be manifestations of a food allergy; however, IgE-mediated food allergy only affects 1% to 4% of adults, with seafood, tree nuts, peanuts, fruits, and vegetables being the most common triggers. Diagnosis is challenging and most commonly achieved through careful evaluation of clinical history followed by elimination and reintroduction or challenge with the suspected offending food. With acute-onset allergic reactions, estimation of food-specific IgE antibodies is frequently used to confirm or refute the diagnosis. Recent developments, such as single allergen assays, enhance the diagnosis of IgE-mediated food allergy, but the gold standard remains oral food challenge. Despite recent advances in the management of food allergy, including the promotion of oral tolerance, the mainstay of management is still the avoidance of food triggers. Dietary management can be compromised by nutritional inadequacy, accidental exposure, food labeling, and quality of life or adherence issues. It is essential that adults with confirmed food allergy receive optimal nutrition and dietetic support to enable them to manage their condition.

Role of basophil activation test for monitoring the immunological changes during desnsitization to cow’s milk: a case report

The basophil activation test (BAT) has proven to be a useful tool for the diagnosis of IgE-mediated food allergy and the evaluation of clinical tolerance in food allergic patients. Until now, successful oral desensitization to food allergen has been correlated with changes in cytokine production (IL-4 and INF-γ) and allergen-specific IgE and IgG4 antibodies. We report a case of a 12-year-old male affected by cow’s milk allergy. The diagnosis was based on a positive allergological work-up, included skin prick test with commercial food extracts (Alk-Abello) and fresh cow’s milk (prick-by-prick method), detection in serum of total and specific IgE (ImmunoCAP System, Phadia), basophil activation test and finally a double-blind placebo-controlled food challenge. Skin prick test, specific IgE, BAT and oral food challenge were positive and so we decided to carry on a sublingual-oral desensitization treatment with cow’s milk, performed according to standardized protocol. In order to evaluate the immunological changes occurred during the immunotherapy, we performed further laboratory tests, included the detection in serum of total and specific IgE and BAT at the end of protocol. Desensitization was successfully carried out within 12 months, reaching the maximum dose of 150 ml of cow’s milk without side effects. The patient showed a decrease of specific IgE levels without reaching normal values and an increase of specific IgG4 levels; whereas the BAT starting from a positive value of 59% became negative after 12 months of treatment. This case report shows how it is possible to monitor allergen-specific basophil responses using the flow cytometry in order to identify an acquired tolerance induced by desensitization. Although further studies are needed, it was interesting to note that the basophil activation test seems to be more sensitive and characterized by a close correlation with the clinical tolerance.

Guidelines for the Diagnosis and Management of Food Allergy in the United States: Summary of the NIAID-Sponsored Expert Panel Report

Guidelines for the Diagnosis and Management of Food Allergy in the United States: Summary of the NIAID-Sponsored Expert Panel Report

Can conjunctival provocation test facilitate the diagnosis of food allergy in children?

Background Food allergy is common in children, occurring in 5–7.5%. The diagnosis may, however, be difficult. Elevated IgE or positive skin prick test to a food allergen is often considered proof of allergy, but may represent sensitisation without clinical manifestations. For a precise diagnosis oral challenge is necessary, but this is often not performed because of risk of serious allergic reactions. The aim of this study was to evaluate whether conjunctival provocation test would facilitate the diagnosis of IgE-mediated food allergy. Methods One hundred and forty-nine children with 174 possible diagnoses of food allergy were included. General examination, skin prick test and specific IgE were performed, as well as conjunctival provocation test of the suspected food allergen. Open food challenges and double-blind placebo controlled tests were performed in order to diagnose possible food allergy. Results Forty-six children with strongly positive conjunctival reactions (rubor, itching, oedema) to fifty food allergens were all proven to have allergy to the food in question. The children with negative conjunctival provocation tests showed no allergic reactions when challenged. Conclusions We find that a strongly positive conjunctival reaction to a food allergen correlates well with true allergy. An oral challenge should be carefully performed. With a negative conjunctival test an oral challenge may safely be performed.

Basophil activation tests in food allergy

Basophil activation tests in food allergy