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.

Development of sensitization to peanut and storage proteins and relation to markers of airway and systemic inflammation: A 24-year follow-up.

BACKGROUND: Long-time data of peanut allergy over time is sparse. We aimed to study the longitudinal development of sensitization to peanut extract and storage protein allergen molecules and associations with asthma status, airway and systemic inflammation markers. METHODS: The Swedish birth cohort BAMSE followed 4089 participants with questionnaires, clinical investigations and blood sampling between 0 and 24 years. Information on (i) background factors at 2 months, (ii) peanut allergy symptoms and IgE data (ImmunoCAP) at 4, 8, 16, and 24 years, and (iii) IgE to storage proteins, lung function data including exhaled nitric oxide (FENO) as well as systemic inflammatory markers at 24 years of age were collected. RESULTS: The prevalence of peanut extract sensitization, defined as IgE ≥ 0.35 kUA /L, was 5.4%, 8.0%, 7.5%, and 6.2% at 4, 8, 16, and 24 years of age, respectively. Between 8 and 24 years of age, (33/1565) participants developed IgE-ab to peanut extract (median 1,4, range 0.7-2.6 kUA /L), and among those 85% were also sensitized to birch. Only six individuals developed sensitization to Ara h 2 (≥0.1 kUA /L) between 8 and 24 years of age, of whom three had an IgE-ab level between 0.1-0.12 kUA /L. Storage protein sensitization was associated with elevated FENO, blood eosinophils and type 2 inflammation-related systemic proteins. CONCLUSION: Sensitization to peanut extract after 4 years of age is mainly induced by birch cross-sensitization and IgE to Ara h 2 rarely emerges after eight years of age. Storage protein sensitization is associated with respiratory and systemic inflammation.

Unusual and Unexpected Allergic Reactions Can Be Unraveled by Molecular Allergy Diagnostics.

The fifth class of immunoglobulin, immunoglobulin E (IgE) was discovered in 1967 and has had immense importance for the understanding, diagnosis, and treatment of allergic disease. More than 50 years have passed and efforts to characterize, standardize, and refine allergens with the aim to improve clinical diagnosis and allergen-specific immunotherapy are still ongoing. Another important breakthrough was made in 1999 with the introduction of component-resolved diagnostics (CRD), making it possible to quantify IgE antibodies against individual allergen proteins for diagnostic purposes at a molecular level. The progress and developments made in allergy diagnosis often originate from clinical observations and case studies. Observant physicians and health-care personnel have reported their findings in the medical literature, which in turn has inspired researchers to become involved in clinical research. Allergists continuously encounter new allergies and are often asked by their patients how to prevent new reactions. In the current article, we focus on recent clinical observations that can now be explained by CRD. The examples taken concern allergic reactions toward peanuts, tree nuts, lemon kernels, health drinks, meat, insects, dog dander, cannabis, and semen. We now have an improved understanding of why patients may react in a serious or unexpected way, as illustrated by these examples, yet many other clinical observations remain unexplained. The aim of this review is to highlight the importance of clinical observations among allergic patients, focusing on systemic, or unusual and unexpected allergic reactions, where component-testing has further refined the diagnosis of IgE-mediated allergy.

Detection of subclinical vitamin K deficiency in neurosurgery with PIVKA-II.

Vitamin K is known for supporting the carboxylation of hepatic coagulation proteins. Levels of proteins induced by vitamin K absence for factor II (PIVKA-II) reflect hypocarboxylated prothrombin and can be used to detect subclinical vitamin K deficiency. The aim of this study was to determine the prevalence of perioperative subclinical vitamin K deficiency among neurosurgical patients using PIVKA-II and investigate the existence of any correlation to standard coagulation assays. Also, the antitumor effects of vitamin K were reviewed. Thirty-five patients undergoing brain tumor resection were included. Blood samples were drawn preoperatively, at the end of surgery and in the morning after surgery. In addition to PIVKA-II, factor II and the Owren and Quick prothrombin times were analyzed. Seventeen of 35 patients had elevated PIVKA-II levels before surgery, which continued to be above normal range postoperatively. Median PIVKA-II and Owren prothrombin time (PT-INR) were increased on the morning day 1 postoperatively compared to before surgery, whereas Quick end-stage prothrombin time (EPT) decreased and factor II was unaffected. Postoperative complications were connected to high PIVKA-II increases. Positive correlations between PIVKA-II and factor II and body mass index (BMI) were found. In conclusion, PIVKA-II was increased in many patients preoperatively and then increased by the morning following surgery. Standard coagulation assays were largely non-pathological. Correlations were demonstrated between PIVKA-II and factor II and BMI. The effect of perioperative treatment with different vitamin K supplements should be investigated in future studies, as well as clinical trials evaluating their antitumor effects.