The true global scale of anaphylaxis remains elusive, because many episodes occur in the community without presentation to health care facilities, and most regions have not yet developed reliable ...systems with which to monitor severe allergic events. The most robust data sets currently available are based largely on hospital admissions, which are limited by inherent issues of misdiagnosis, misclassification, and generalizability. Despite this, there is convincing evidence of a global increase in rates of all-cause anaphylaxis, driven largely by medication- and food-related anaphylaxis. There is no evidence of parallel increases in global all-cause anaphylaxis mortality, with surprisingly similar estimates for case-fatality rates at approximately 0.5% to 1% of fatal outcomes for hospitalizations due to anaphylaxis across several regions. Studying regional patterns of anaphylaxis to certain triggers have provided valuable insights into susceptibility and sensitizing events: for example, the link between the mAb cetuximab and allergy to mammalian meat. Likewise, data from published fatality registers can identify potentially modifiable risk factors that can be used to inform clinical practice, such as prevention of delayed epinephrine administration, correct posturing during anaphylaxis, special attention to populations at risk (such as the elderly on multiple medications), and use of venom immunotherapy in individuals at risk of insect-related anaphylaxis.
Background Epidemiologic evidence suggests delayed introduction of egg might not protect against egg allergy in infants at risk of allergic disease. Objective We sought to assess whether dietary ...introduction of egg between 4 and 6 months in infants at risk of allergy would reduce sensitization to egg. Methods We conducted a randomized controlled trial in infants with at least 1 first-degree relative with allergic disease. Infants with a skin prick test (SPT) response to egg white (EW) of less than 2 mm were randomized at age 4 months to receive whole-egg powder or placebo (rice powder) until 8 months of age, with all other dietary egg excluded. Diets were liberalized at 8 months in both groups. The primary outcome was an EW SPT response of 3 mm or greater at age 12 months. Results Three hundred nineteen infants were randomized: 165 to egg and 154 to placebo. Fourteen infants reacted to egg within 1 week of introduction (despite an EW SPT response <2 mm at entry) and were unsuitable for intervention. Two hundred fifty-four (83%) infants were assessed at 12 months of age. Loss to follow-up was similar between groups. Sensitization to EW at 12 months was 20% and 11% in infants randomized to placebo and egg, respectively (odds ratio, 0.46; 95% CI, 0.22-0.95; P = .03, χ2 test). The absolute risk reduction was 9.8% (95% CI, 8.2% to 18.9%), with a number needed to treat of 11 (95% CI, 6-122). Levels of IgG4 to egg proteins and IgG4 /IgE ratios were higher in those randomized to egg ( P < .0001 for each) at 12 months. There was no effect on the proportion of children with probable egg allergy (placebo, 13; egg, 8). Conclusions Introduction of whole-egg powder into the diets of high-risk infants reduced sensitization to EW and induced egg-specific IgG4 levels. However, 8.5% of infants randomized to egg were not amenable to this primary prevention.
Background Food protein–induced enterocolitis syndrome (FPIES) is a non–IgE-mediated gastrointestinal allergic disorder. Large population-based FPIES studies are lacking. Objective We sought to ...determine the incidence and clinical characteristics of FPIES in Australian infants. Methods An Australia-wide survey (2012-2014) was undertaken through the Australian Paediatric Surveillance Unit, with monthly notification of new cases of acute FPIES in infants aged less than 24 months by 1400 participating pediatricians. Results Two hundred thirty infants with FPIES were identified. The incidence of FPIES in Australian infants (<24 months) was 15.4/100,000/y. Median age of first episode, diagnosis, and notification were 5, 7, and 10 months, respectively. There was no sex predilection. Seven percent of infants had siblings with a history of FPIES, and 5% reacted during exclusive breast-feeding. Sixty-eight had a single food trigger (20% had 2 and 12% had ≥3 food triggers). The most common FPIES triggers were rice (45%), cow's milk (33%), and egg (12%). Fifty-one percent of infants reacted on their first known exposure. Infants with FPIES to multiple versus single food groups were younger at the initial episode (4.6 vs 5.8 months mean, P = .001) and more frequently had FPIES to fruits, vegetables, or both (66% vs 21%, P < .0001). Infants exclusively breast-fed for more than 4 months had a trend toward lower rates of FPIES to multiple food groups (23% vs 36%, P = .06). Sixty-four percent of infants with FPIES to multiple foods, which included cow's milk, had coassociated FPIES to solid foods. Forty-two percent of infants with FPIES to fish reacted to other food groups. Conclusions FPIES is not rare, with an estimated incidence of 15.4/100,000/y. Rice is the most common food trigger in Australia. Factors associated with FPIES to multiple foods included early-onset disease and FPIES to fruits, vegetables, or both.
Introduction
The Australasian Society of Clinical Immunology and Allergy, the peak professional body for clinical immunology and allergy in Australia and New Zealand, develops and provides ...information on a wide range of immune‐mediated disorders, including advice about infant feeding and allergy prevention for health professionals and families. Guidelines for infant feeding and early onset allergy prevention were published in 2016, with additional guidance published in 2017 and 2018, based on emerging evidence.
Main recommendations
When the infant is ready, at around 6 months, but not before 4 months, start to introduce a variety of solid foods. (This is not a strict window of introduction but rather a recommendation not to delay the introduction of solid foods beyond 12 months.)
Introduce peanut and egg in the first year of life in all infants, regardless of their allergy risk factors.
Hydrolysed (partially and extensively) formula is no longer recommended for the prevention of allergic disease.
Changes in management a result of the guidelines
The guidelines specifically recommend introducing solid foods at around 6 months of age and introducing peanut and egg in the first year of life in all infants to prevent allergy development. Hydrolysed formula is no longer recommended for prevention of allergic disease. A new document outlining the reasons for and the method of peanut introduction to high risk infants is available for health professionals.
Fatal Anaphylaxis: Mortality Rate and Risk Factors Turner, Paul J.; Jerschow, Elina; Umasunthar, Thisanayagam ...
The journal of allergy and clinical immunology in practice (Cambridge, MA),
09/2017, Letnik:
5, Številka:
5
Journal Article
Recenzirano
Odprti dostop
Up to 5% of the US population has suffered anaphylaxis. Fatal outcome is rare, such that even for people with known venom or food allergy, fatal anaphylaxis constitutes less than 1% of total ...mortality risk. The incidence of fatal anaphylaxis has not increased in line with hospital admissions for anaphylaxis. Fatal drug anaphylaxis may be increasing, but rates of fatal anaphylaxis to venom and food are stable. Risk factors for fatal anaphylaxis vary according to cause. For fatal drug anaphylaxis, previous cardiovascular morbidity and older age are risk factors, with beta-lactam antibiotics, general anesthetic agents, and radiocontrast injections the commonest triggers. Fatal food anaphylaxis most commonly occurs during the second and third decades. Delayed epinephrine administration is a risk factor; common triggers are nuts, seafood, and in children, milk. For fatal venom anaphylaxis, risk factors include middle age, male sex, white race, cardiovascular disease, and possibly mastocytosis; insect triggers vary by region. Upright posture is a feature of fatal anaphylaxis to both food and venom. The rarity of fatal anaphylaxis and the significant quality of life impact of allergic conditions suggest that quality of life impairment should be a key consideration when making treatment decisions in patients at risk for anaphylaxis.
Summary
Food protein‐induced enterocolitis syndrome (FPIES) is a poorly understood non‐IgE gastrointestinal‐mediated food allergy that predominantly affects infants and young children.
Cells of the ...innate immune system appear to be activated during an FPIES reaction.
Acute FPIES typically presents between one and 4 hours after ingestion of the trigger food, with the principal symptom being profuse vomiting, and is often accompanied by pallor and lethargy. Additional features can include hypotension, hypothermia, diarrhoea, neutrophilia and thrombocytosis.
In Australia, the most commonly reported foods responsible for FPIES are (in descending order) rice, cow's milk, egg, oats and chicken.
Most children with FPIES react to only one food trigger, and thus, avoidance of multiple foods is often not indicated.
FPIES is often misdiagnosed as sepsis or gastroenteritis. However, a diagnosis of FPIES is favoured if there is rapid resolution of symptoms within hours of presentation, an absence of fever, and a lack of a significant rise in C‐reactive protein at presentation.
Diagnosis is often hampered by the lack of awareness of FPIES, absence of reliable biomarkers, the non‐specific nature of the presenting symptoms, and the delay between allergen exposure and symptoms.
Although some national peak allergy bodies have attempted to improve the diagnosis and management of FPIES, up until 2017 there were no internationally agreed guidelines for its diagnosis and management.
PURPOSE OF REVIEWThe observed increase in incidence of allergic disease in many regions over the past 3 decades has intensified interest in understanding the epidemiology of severe allergic ...reactions. We discuss the issues in collecting and interpreting these data and highlight current deficiencies in the current methods of data gathering.
RECENT FINDINGSAnaphylaxis, as measured by hospital admission rates, is not uncommon and has increased in the United Kingdom, the United States, Canada, and Australia over the last 10–20 years. All large datasets are hampered by a large proportion of uncoded, ‘unspecified’ causes of anaphylaxis. Fatal anaphylaxis remains a rare event, but appears to be increasing for medication in Australia, Canada, and the United States. The rate of fatal food anaphylaxis is stable in the United Kingdom and the United States, but has increased in Australia. The age distribution for fatal food anaphylaxis is different to other causes, with data suggesting an age-related predisposition to fatal outcomes in teenagers and adults to the fourth decade of life.
SUMMARYThe increasing rates of food and medication allergy (the latter exacerbated by an ageing population) has significant implications for future fatality trends. An improved ability to accurately gather and analyse population-level anaphylaxis data in a harmonized fashion is required, so as to ultimately minimize risk and improve management.
Background
Commercial allergen extracts for allergy skin prick testing (SPT) are widely used for diagnosing fish allergy. However, there is currently no regulatory requirement for standardization of ...protein and allergen content, potentially impacting the diagnostic reliability of SPTs. We therefore sought to analyse commercial fish extracts for the presence and concentration of fish proteins and in vitro IgE reactivity using serum from fish‐allergic patients.
Methods
Twenty‐six commercial fish extracts from five different manufacturers were examined. The protein concentrations were determined, protein compositions analysed by mass spectrometry, followed by SDS‐PAGE and subsequent immunoblotting with antibodies detecting 4 fish allergens (parvalbumin, tropomyosin, aldolase and collagen). IgE‐reactive proteins were identified using serum from 16 children with confirmed IgE‐mediated fish allergy, with focus on cod, tuna and salmon extracts.
Results
The total protein, allergen concentration and IgE reactivity of the commercial extracts varied over 10‐fold between different manufacturers and fish species. The major fish allergen parvalbumin was not detected by immunoblotting in 6/26 extracts. In 7/12 extracts, five known fish allergens were detected by mass spectrometry. For cod and tuna, almost 70% of patients demonstrated the strongest IgE reactivity to collagen, tropomyosin, aldolase A or β‐enolase but not parvalbumin.
Conclusions
Commercial fish extracts often contain insufficient amounts of important allergens including parvalbumin and collagen, resulting in low IgE reactivity. A comprehensive proteomic approach for the evaluation of SPT extracts for their utility in allergy diagnostics is presented. There is an urgent need for standardized allergen extracts, which will improve the diagnosis and management of fish allergy.
Commercial skin prick test (SPT) extracts often contain insufficient amounts of important fish allergens, resulting in low IgE reactivity. Collagen, tropomyosin and aldolase A are of under‐recognized importance for the diagnosis of fish allergy. Understanding the molecular allergology of SPT allergen extracts is essential for best diagnostics.
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