Food allergy is a growing health problem affecting both pediatric and adult patients. Food allergies are often immunoglobulin E (IgE) mediated but other food-induced non-IgE-mediated diseases exist. Diagnosis of food allergy relies on the combination of clinical and reaction history, skin and IgE testing as well as oral food challenges. Although oral immunotherapy has been able to achieve sustained unresponsiveness in some patients, no cure for food allergies has been found to date. Avoidance of the inciting food as well as availability of epinephrine autoinjectors remains the mainstay of treatment.

Guidelines and recommendations for the diagnosis and management of cow\'s milk allergy (CMA) in childhood are based on scientific review of the available evidence. While this approach is the most rigorous, guidelines may not fully address all scenarios encountered by clinicians. Many symptoms of CMA overlap with other common childhood illnesses and are subjectively reported by the caregivers of the infant, as is the interpretation of the dietary interventions. Additionally, many healthcare professionals and caregivers do not follow the recommendations to perform an oral food challenge or reintroduction of cow\'s milk after a diagnostic elimination diet because (1) the infant is doing well and (2) the carer\'s fear of symptoms relapsing with this procedure. As a result, CMA in infants may be either under-diagnosed leading to reduced quality of life for families or over-diagnosed, resulting in unnecessary long-term elimination diets and increasing the risk for nutritional deficiencies. This paper discusses some of these controversial topics, focusing on misdiagnosis and mismanagement in clinical practice. The lack of objective diagnostic criteria can hamper the diagnosis and management of CMA in daily practice.

Omalizumab is a recombinant humanized monoclonal antibody against immunoglobulin E., which can specifically bind to IgE in blood and inhibit the release of inflammatory mediators to improve the symptoms of IgE-mediated asthma effectively. This meta-analysis was used to retrieve the studies in recent years to provide a clinical reference for the omalizumab in treating allergic asthma (AA).
The databases Ovid, Embase, Pubmed, the Cochrane Library of clinical trials, CNKI (China National Knowledge Infrastructure) (China), and Wangfang Data (China) were searched for all studies on omalizumab involvement in treating allergic childhood asthma up to January 2022. Effectiveness, rate of exacerbation within 24 weeks (and 52 weeks), and the incidence of adverse reactions and serious adverse reactions were used as the primary data analysis indicators.
Seven eligible pieces of literature were included. Meta-analysis indicated that omalizumab could significantly improve the treatment efficacy in children with asthma [RR (Risk Ratio) = 1.24, 95% CI (Confidential Interval) (1.09, 1.41), Z = 3.30, p = 0.001], reduced the incidence of significant clinical exacerbation in children with asthma within 24 weeks [RR = 0.55, 95% CI (0.35, 0.85), Z = -2.67, p = 0.001], reduced the incidence of significant clinical exacerbation in children with asthma within 52 weeks [RR = 0.52, 95% CI (0.39, 0.71), Z = -4.2, p < 0.0001], and the incidence of total serious adverse reactions was not statistically different from placebo [RR = 1.00, 95% CI (0.98, 1.03), Z = 0.71, p = 0.479], the incidence of serious adverse reactions was significantly decreased [RR = 0.53, 95% CI (0.36, 0.77), Z = -3.35, p = 0.001].
In treating IgE (immunoglobulin E)-mediated asthma in children, adding oral (or subcutaneous) omalizumab to a glucocorticoid regimen can enhance the effectiveness of treatment, reduce the probability of significant exacerbation during treatment, and reduce the incidence of serious adverse reactions.

Food allergy is a growing health problem affecting both pediatric and adult patients. Food allergies are often immunoglobulin E (IgE) mediated but other food-induced non-IgE-mediated diseases exist. Diagnosis of food allergy relies on the combination of clinical and reaction history, skin and IgE testing as well as oral food challenges. Although oral immunotherapy has been able to achieve sustained unresponsiveness in some patients, no cure for food allergies has been found to date. Avoidance of the inciting food as well as availability of epinephrine autoinjectors remains the mainstay of treatment.

Vaccine anaphylaxis is rare; however, severe allergic reactions after administration of a coronavirus disease 2019 (COVID-19) vaccines have been reported. Excipients in the vaccine may play a role in severe allergic reactions post-vaccination. Various mechanisms, including IgE-mediated pathways, direct mass cell stimulation via the Mas-related G protein-coupled receptor-X2, and complement pathway activation, have been proposed to cause the anaphylaxis. Skin testing, using the basophil activation test, has been used to clarify the mechanism of the anaphylaxis and provide safety information for the next injection. Here, we review the current evidence and suggested approaches for patients who experienced an immediate severe allergic reaction to the first dose of a COVID-19 vaccine.

Vaccine-associated hypersensitivity reactions are not infrequent; however, serious acute-onset, presumably IgE-mediated or IgG and complement-mediated anaphylactic or serious delayed-onset T cell-mediated systemic reactions are considered extremely rare. Hypersensitivity can occur because of either the active vaccine component (antigen) or one of the other components. Postvaccination acute-onset hypersensitivity reactions include self-limited localized adverse events and, rarely, systemic reactions ranging from urticaria/angioedema to full-blown anaphylaxis with multisystem involvement. Risk of anaphylaxis after all vaccines is estimated to be 1.31 (95% CI, 0.90-1.84) per million vaccine doses, respectively. Serious hypersensitivity reactions after influenza vaccines are particularly important because of the large number of persons vaccinated annually. Influenza vaccines are unique in requiring annual changes in the vaccines\' antigenic composition to match the predicted circulating influenza strains. Recently, novel influenza vaccine types were introduced in the United States (recombinant vaccines, some with higher antigen content and a new adjuvanted vaccine). Providers should be aware of changing recommendations on the basis of recent published evidence for persons with a history of egg allergy to receive annual influenza vaccination. Further research is needed to elucidate the pathophysiology and risk factors for reported vaccine-associated adverse events. Further research is also needed to determine whether repeated annual inactivated influenza vaccination, the number of vaccine antigens administered at the same time, and the current timing of routine infant vaccinations are optimal for overall population well-being.

BACKGROUND: Anaphylactic reactions involving IgE mediated hypersensitivity have been frequently reported for a number of uncommon foods. However, cases of anaphylaxis to over the counter vitamins and oral supplements have been rarely published. Lactose intolerance affects approximately 20% of Canadians and roughly 70% of the world\'s population of any age. Lactose intolerance develops primarily due to the absence of the enzyme lactase and treatment involves avoidance of lactose-containing foods or ingestion of commercially available lactase enzyme preparations prior to their consumption. This case report represents the first documented evidence of anaphylaxis after exposure to supplemental lactase enzyme preparation.
METHODS: A 38 years old Caucasian female presented with a history of self-diagnosed adult-onset lactose intolerance and a suspected allergy to lactase containing tablets. She reported an episode of bilateral orbital swelling, shortness of breath, and throat constriction after oral ingestion of a supplemental lactase enzyme tablet. Her symptoms slowly resolved with the administration of inhaled salbutamol and oral diphenhydramine. She handled lactase tablets for years to her children who were lactose intolerant, but had never ingested the tablets herself prior to the reported episode. In clinic, physical examination was benign, and skin prick testing to a slurry of the lactase tablet revealed a strongly positive reaction wheal size of 10 mm and flare of 60 mm with normal controls. The patient reported throat tightness and constriction after skin prick testing and required cetirizine treatment and observation in clinic. Subsequent skin testing was performed with individual ingredients of the lactase tablet provided by the manufacturer and Aspergillus niger, a common bacteria used in lactase preparations. Only concentrated lactase enzyme elicited a positive response. The patient was diagnosed with lactase tablet induced anaphylaxis due to synthetic lactase enzyme IgE mediated allergy, and was advised to avoid all products containing lactase enzymes as an ingredient and to carry an epinephrine auto-injector.
CONCLUSIONS: This is the first documented case report of an anaphylactic reaction to supplemental lactase enzyme. This case report reinforces the importance of thorough allergy assessment, education on avoidance of triggers, in particular with uncommon allergens.

BACKGROUND: Drugs are responsible for 40% to 60% of anaphylactic reactions treated in the emergency department. A global research agenda to address uncertainties in anaphylaxis includes studies that identify factors associated with morbidity and mortality.
OBJECTIVE: The present study investigated drug-induced anaphylaxis, etiologies, aggravating factors, and treatment.
METHODS: A total of 806 patients with adverse drug reactions were screened, and those who had a clinical diagnosis of anaphylaxis were included in the study. Clinical and demographic characteristics of anaphylaxis were described, including etiologies, pathophysiologic mechanisms involved in the reactions, and a personal history of atopy and asthma. Factors associated with disease severity also were identified.
RESULTS: Anaphylaxis was diagnosed in 117 patients (14.5%). The etiologies were defined in 76% of the cases, nonsteroidal anti-inflammatory drugs being the most frequent. Seventy-eight patients (66.7%) reported a previous reaction to the drug involved in the current reaction or to a drug from the same class and/or group. Epinephrine was used to treat 34.2% of patients who presented with anaphylaxis, and 40.8% of those with anaphylactic reactions with cardiovascular involvement. IgE-mediated reactions were associated with greater severity, manifested by the rates of cardiovascular dysfunction, hospitalization, and use of epinephrine.
CONCLUSIONS: The prevalence of anaphylaxis is high in patients who seek medical assistance for drug reactions, but its diagnosis is missed in emergency services, and adrenaline is underused. Drugs were prescribed to many patients despite a history of previous reaction. Nonsteroidal anti-inflammatory drugs were implicated in most cases of anaphylaxis induced by drugs, and IgE-mediated reactions were less frequent but more severe.

BACKGROUND: Inpatient providers have varying levels of knowledge in managing patients with drug and/or penicillin (PCN) allergy.
OBJECTIVE: Our objectives were (1) to survey inpatient providers to ascertain their baseline drug allergy knowledge and preparedness in caring for patients with PCN allergy, and (2) to assess the impact of an educational program paired with the implementation of a hospital-based clinical guideline.
METHODS: We electronically surveyed 521 inpatient providers at a tertiary care medical center at baseline and again 6 weeks after an educational initiative paired with clinical guideline implementation. The guideline informed providers on drug allergy history taking and antibiotic prescribing for inpatients with PCN or cephalosporin allergy.
RESULTS: Of 323 unique responders, 42% (95% CI, 37-48%) reported no prior education in drug allergy. When considering those who responded to both surveys (n = 213), we observed a significant increase in knowledge about PCN skin testing (35% vs 54%; P < .001) and loss of PCN allergy over time (54% vs 80%; P < .0001). Among those who reported attending an educational session (n = 62), preparedness to determine if an allergy was severe significantly improved (77% vs 92%; P = .03). Other areas, including understanding absolute contraindications to receiving a drug again and PCN cross-reactivity with other antimicrobials, did not improve significantly.
CONCLUSIONS: Inpatient providers have drug allergy knowledge deficits but are interested in tools to help them care for inpatients with drug allergies. Our educational initiative and hospital guideline implementation were associated with increased PCN allergy knowledge in several crucial areas. To improve care of inpatients with drug allergy, more research is needed to evaluate hospital policies and sustainable educational tools.