Update in pediatric anaphylaxis: a systematic review

Extrinsic and Intrinsic Modulators of Anaphylaxis

The severity of anaphylaxis is determined by many factors. The allergenic source as well as the age of the affected individual and the route of allergen exposure encompass the major contributors of the clinical outcome. Moreover, the severity can be modulated further by intrinsic and extrinsic factors. Among these, the genetic predisposition, certain comorbidities such as uncontrolled asthma, and hormonal fluctuations have been proposed as intrinsic and antihypertensive medications or physical activity as extrinsic factors. Recent advances have highlighted immunologic pathways that may exacerbate the response to allergens through receptors on mast cells, basophils, platelets, and other granulocytes. Atopy, platelet-activating factor acetylhydrolase deficiency, hereditary alpha tryptasemia, and clonal mast cell disorders are examples associated with genetic alterations that may predispose to severe anaphylaxis. Identifying risk factors that lower the threshold of reactivity or increase the severity of multisystem reactions is important in the management of this patient population.

Prehospital Epinephrine Use in Pediatric Anaphylaxis by Emergency Medical Services

OBJECTIVES

Anaphylaxis requires prompt assessment and management with epinephrine to reduce its morbidity and mortality. This study examined the prehospital management of pediatric anaphylactic reactions in Northeast Ohio.

METHODS

This is a retrospective chart review using emergency medical service (EMS) run charts of patients 18 years and younger from February 2015 to April 2019. Patient charts with the diagnosis of "anaphylaxis" or "allergic reaction" were reviewed and confirmed that symptoms met anaphylaxis criteria. Information regarding epinephrine administration before EMS arrival and medications given by EMS providers was collected. Analysis was performed using descriptive statistics.

RESULTS

From 646 allergic/anaphylactic reaction EMS run charts, 150 (23%) met the guideline criteria for anaphylaxis. The median patient age was 12 years. Only 57% (86/150) of these patients received intramuscular epinephrine, and the majority received it before EMS arrival. Epinephrine was administered by EMS to 32% (30/94; 95% confidence interval [CI], 22.7% to 42.3%) of patients who had not already received epinephrine. The odds of receiving prehospital epinephrine were significantly lower for patients 5 years and younger (risk difference [RD], -0.23; 95% CI, -0.43 to -0.04), those with no history of allergic reaction (RD, -0.20; 95% CI, -0.38 to -0.03), those who presented with lethargy (RD, -0.43; 95% CI, -0.79 to -0.06), and those whose trigger was a medication or environmental allergen (RD, -0.47; 95% CI, -0.72 to -0.23 for each).

CONCLUSIONS

Emergency medical service providers in this region demonstrated similar use of epinephrine as reported elsewhere. However, 43% (64/150) of pediatric patients meeting anaphylaxis criteria did not receive prehospital epinephrine, and 10% (15/150) received no treatment whatsoever. Efforts to improve EMS provider recognition and prompt epinephrine administration in pediatric cases of anaphylaxis seem necessary.

Diagnosing, managing and preventing anaphylaxis: Systematic review

BACKGROUND

This systematic review used the GRADE approach to compile evidence to inform the European Academy of Allergy and Clinical Immunology's (EAACI) anaphylaxis guideline.

METHODS

We searched five bibliographic databases from 1946 to 20 April 2020 for studies about the diagnosis, management and prevention of anaphylaxis. We included 50 studies with 18 449 participants: 29 randomized controlled trials, seven controlled clinical trials, seven consecutive case series and seven case-control studies. Findings were summarized narratively because studies were too heterogeneous to conduct meta-analysis.

RESULTS

It is unclear whether the NIAID/FAAN criteria or Brighton case definition are valid for immediately diagnosing anaphylaxis due to the very low certainty of evidence. There was also insufficient evidence about the impact of most anaphylaxis management and prevention strategies. Adrenaline is regularly used for first-line emergency management of anaphylaxis but little robust research has assessed its effectiveness. Newer models of adrenaline autoinjectors may slightly increase the proportion of people correctly using the devices and reduce time to administration. Face-to-face training for laypeople may slightly improve anaphylaxis knowledge and competence in using autoinjectors. We searched for but found little or no comparative effectiveness evidence about strategies such as fluid replacement, oxygen, glucocorticosteroids, methylxanthines, bronchodilators, management plans, food labels, drug labels and similar.

CONCLUSIONS

Anaphylaxis is a potentially life-threatening condition but, due to practical and ethical challenges, there is a paucity of robust evidence about how to diagnose and manage it.

Nationwide Survey of Hospitalization Due to Pediatric Food-Induced Anaphylaxis in the United States

OBJECTIVE

Anaphylaxis is a common, serious, systemic allergic reaction. In the United States, the change of annual hospitalization rates by anaphylaxis-trigger foods and risk factors associated with severity remain unclear.

METHODS

Hospital discharge records of food-induced anaphylactic reactions of individuals younger than 20 years were obtained from Kids' Inpatient Database in 2006, 2009, and 2012 and were weighted to estimate the number of hospitalizations in the United States. We identified annual hospitalization rates by patients' characteristics and anaphylaxis-trigger foods and investigated factors associated with severity and use of mechanical ventilation with multivariable logistic regression.

RESULTS

A total of 3427 hospitalizations were obtained, and annual hospitalization rates showed a significantly increasing trend from 1.2 per 100,000 children in 2006 to 1.5 per 100,000 children in 2012 (P < 0.001). The leading causes of hospitalizations due to food-induced anaphylaxis were peanuts (0.35-0.48 per 100,000 children), tree nuts and seeds (0.20-0.32 per 100,000 children), and milk products (0.09-0.13 per 100,000 children), with significantly increasing trends during 2006-2012. Milk products were significantly associated with severity (odds ratio [OR], 2.0; 95% confidence interval [CI], 1.3-2.9). Ages between 13 and 20 years (OR, 2.7; 95% CI, 1.4-5.1) and comorbidity of asthma (OR, 2.1; 95% CI, 1.3-3.4) were significantly associated with the use of mechanical ventilation.

CONCLUSIONS

The annual hospitalization rates in the entire United States showed an increasing trend during 2006-2012. The rates of peanuts, tree nuts and seeds, and milk products demonstrated upward trends. Milk products, ages between 13 and 20 years, and comorbidities of asthma were related to severity and morbidity.

Missed Registration of Disease Codes for Pediatric Anaphylaxis at the Emergency Department

Background

It is important to register anaphylaxis codes correctly to study the exact prevalence of anaphylaxis. The purpose of this study was to analyze the clinical characteristics and disease codes of inaccurately registered groups in pediatric anaphylaxis patients.

Methods

This study reviewed the medical records of all pediatric patients who presented to the university hospital emergency department over a 5-year period. Study subjects were divided into 2 groups: the accurate group, including those registered under anaphylaxis codes, and the inaccurate coding group, including those registered under other codes.

Results

From a total of 79,676 pediatric patients, 184 (0.23%) had anaphylaxis. Of these, 23 (12.5%) and 161 (87.5%) patients were classified to the accurate and inaccurate coding groups, respectively. Average age, time from symptom onset to emergency department presentation, past history of allergy, and penicillin and cephalosporin as causes of anaphylaxis differed between the 2 groups. Cardiovascular (39.1% vs. 5.6%, p=0.001) and respiratory symptoms (65.2% vs. 42.2%, p=0.038) manifested more frequently in the accurate group, while gastrointestinal symptoms (68.3% vs. 26.1%, p=0.001) were more frequently observed in the inaccurate coding group. Fluid administration (82.6% vs. 28.0%, p=0.001), steroid use (60.9% vs. 23.0%, p=0.001), and epinephrine use (65.2% vs. 13.0% p=0.001) were more common treatments for anaphylaxis in the emergency department in the accurate group. Anaphylaxis patients with cardiovascular symptoms, steroid use, and epinephrine use were more likely to be accurately registered with anaphylaxis disease codes.

Conclusions

In the case of pediatric anaphylaxis, more patients were registered inaccurately under other allergy-related codes and simple symptom codes, rather than under anaphylaxis codes. Therefore, future research on anaphylaxis should consider inaccurately registered anaphylactic patients, as shown in this study.

A survey of anaphylaxis etiology and treatment

Identifying the causes of anaphylaxis which is an acute, potentially fatal systemic reaction is very important in every community. Treatment strategies and pitfalls should also be determined. We sought to determine the most common triggers of anaphylaxis, clinical manifestations and treatment strategies in Mashhad, northeast of Iran. An observational cross-sectional study was conducted to evaluate all patients with a history of anaphylactic reaction who were referred to University Allergy Clinics between 2006 and 2016 in Mashhad Iran. We used a combination of patient’s clinical history and allergy diagnostic testing including radioallergosorbant test and skin prick test in order to determine the etiology of anaphylaxis. We identified 172 anaphylactic reactions in 70 patients. Median age was 15 years with a range from 6 months to 48 years. The triggers included: foods, 61.4%; drugs, 15.7%; hymenoptera venom, 8.6%; idiopathic, 5.7%; immunotherapy, 4.3% and other etiologies: 5.7%. Nuts and seeds were the most important triggers of food induced anaphylaxis, especially in school children, adolescents and young adults, followed by fruits. However, Cow’s milk and hen’s egg were the main triggers of anaphylaxis in children aged under 2 years. The most common symptoms were cutaneous and cardiovascular. Corticosteroids (94.3%) and/or antihistamines (85.7%) were used most frequently for treatment followed by intravenous fluids (54.3%), whereas epinephrine was only used in 17.1% of the cases. Food related anaphylaxis and other typical triggers of anaphylaxis are age dependent and the risks and triggers change with age. Epinephrine injection should be increased by improving the awareness of physician and medical teams. The study was approved by the Ethics Committee of the Faculty of Medicine of Mashhad University of Medical Sciences (approved number: IR.MUMS.REC.1393.960).

The Epidemiology of Anaphylaxis

Anaphylaxis is a dramatic expression of systemic allergy. The lifetime prevalence of anaphylaxis is currently estimated at 0.05-2 % in the USA and ~3 % in Europe. Several population-specific studies have noted a rise in the incidence, particularly in the hospitalizations and ER visits due to anaphylaxis. The variable signs and symptoms that constitute the diagnostic criteria for anaphylaxis, the differences in diagnostic algorithms, and the limitations in the current coding systems have made summarizing epidemiologic data and comparing study results challenging. Nevertheless, across all studies, the most common triggers continue to be medications, food, and venom. Various risk factors for more severe reactions generally include older age, history of asthma, and having more comorbid diseases. Interesting seasonal, geographic, and latitude differences have been observed in anaphylaxis prevalence and incidence rates, suggesting a possible role of vitamin D and sun exposure in modifying anaphylaxis risk. While the incidence and prevalence of anaphylaxis appear to be increasing in certain populations, the overall fatality rate remains relatively low.

Time Trends in Food Allergy Diagnoses, Epinephrine Orders, and Epinephrine Administrations in New York City Schools

OBJECTIVES

To assess time trends in food allergy diagnoses, epinephrine autoinjector (EAI) prescriptions, and EAI administrations in the school setting.

STUDY DESIGN

In this retrospective study, deidentified student data from the New York City Department of Health and Mental Hygiene, which oversees >1 million students in 1800 schools, were provided to investigators. Data from school years 2007-2008 to 2012-2013 pertaining to diagnoses of food allergy, student-specific EAI orders, and EAI administrations among students in New York City were analyzed for trends over time, via the use of ORs and χ² calculation.

RESULTS

The prevalences of providing physician documentation of food allergy and EAI orders, and the incidence of EAI administrations, all increased approximately 3-fold over the years of the study. Of 337 EAI administrations, more than one-half used stock EAI, and three-quarters were for students without a student-specific order preceding the incident.

CONCLUSIONS

The rise in food allergy diagnoses, EAI prescriptions, and EAI administrations suggest either a true increase in allergic disease, increased reporting, and/or, in the case of EAI administrations, increased appropriate use. As the majority of EAI administrations used stock supply, availability of nonstudent-specific stock EAI appears vital to management of anaphylaxis in schools. Collaboration between physicians, families, and schools is needed to identify students at risk for severe allergic reactions and to ensure preparedness and availability of EAI in the event of anaphylaxis.

Factors associated with epinephrine administration for anaphylaxis in children before arrival to the emergency department

BACKGROUND

Epinephrine is the first-line treatment for anaphylaxis but may be underused by patients and medical personnel.

OBJECTIVE

To evaluate factors associated with anaphylaxis management before arrival at the emergency department (ED) or urgent care center (UCC).

METHODS

We performed a retrospective review of electronic medical records for all patients aged 0 to 25 years presenting with anaphylaxis to the ED or UCC at a pediatric academic referral center during 2009 to 2013.

RESULTS

A total of 408 patients (mean age, 7.25 years; 62% male) were included for analysis. Only 148 patients (36.3%) received epinephrine before arrival at the ED or UCC. Reactions occurring at home (n = 36/114) were less likely to be treated with epinephrine compared with reactions occurring at school (n = 30/49) (odds ratio [OR], 0.29; 95% confidence interval [CI], 0.15-0.59). The odds of receiving epinephrine before arrival at the ED or UCC were significantly lower with a 2-organ system (OR, 0.50; 95% CI, 0.30-0.85) or 3-organ system (OR, 0.41; 95% CI, 0.21-0.81) presentation compared with 1-organ system involvement. Foods (342 [83.8%]) were the most commonly reported provoking trigger. Patients who did not receive epinephrine before arrival at the ED or UCC were significantly less likely to be discharged to home (OR, 0.56; 95% CI, 0.37-0.86; P = .01).

CONCLUSION

This study identifies factors associated with prehospital management of anaphylaxis for children, which highlight that epinephrine administration may be occurring with considerable delay. Increased awareness and education of caregivers, patients, and medical professionals are necessary to provide optimal management.

Anaphylaxis in the Pediatric Emergency Department: Analysis of 133 Cases After an Allergy Workup

BACKGROUND

Data on the incidence and characteristics of pediatric anaphylaxis are scarce. Reported causes of anaphylaxis are mostly those suspected by the physician in the emergency department (ED), which may not coincide with the real triggers.

OBJECTIVES

To investigate the incidence, management, and etiology of pediatric anaphylaxis in the ED of a Spanish tertiary hospital and to determine the concordance between the suspected etiology in the ED and diagnosis after the allergy workup.

METHODS

We performed an observational, descriptive study of all patients with anaphylaxis attended in the pediatric ED from 2012 to 2014. Cases were considered anaphylaxis based on National Institute of Allergy and Infectious Diseases/Food Allergy and Anaphylaxis Network criteria. We recorded data on clinical characteristics, management, etiology suspected by the ED physician and patient (or relatives), and the workup performed in the allergy department.

RESULTS

We recorded 133 cases of anaphylaxis (incidence, 0.12%), with 20 cases (15%) recorded in children younger than 12 months. Anaphylaxis was correctly diagnosed in the ED in 70 cases (53%). Food allergy was the cause of anaphylaxis in 106 out of 118 studied in the allergy department (AD) (90%). The final etiology differed from the etiology initially suspected in the ED in 42 cases (39%). After the study, the frequency of patients with unidentified triggers decreased by 75%.

CONCLUSIONS

The incidence of anaphylaxis is higher in children than previously reported in adults from the same center, and food is the trigger in most cases. To prevent erroneous diagnoses, the etiology of anaphylaxis should be established after an appropriate workup.

A multicenter study on anaphylaxis caused by peanut, tree nuts, and seeds in children and adolescents

Peanut (PN) and tree nuts (TNs) are common causes of anaphylaxis in Western countries, but no information is available in Korea. To feature clinical characteristics of anaphylaxis caused by PN, TNs, and seeds, a retrospective medical record review was performed in 14 university hospitals in Korea (2009-2013). One hundred and twenty-six cases were identified, with the mean age of 4.9 years. PN, walnut (WN), and pine nut accounted for 32.5%, 41.3%, and 7.1%, respectively. The median values of specific IgE (sIgE) to PN, WN, and pine nut were 10.50, 8.74, and 4.61 kU_A /l, respectively. Among 50 cases managed in the emergency department, 52.0% were treated with epinephrine, 66.0% with steroid, 94.0% with antihistamines, 36.0% with oxygen, and 48.0% with bronchodilator. In conclusion, WN, PN, and pine nut were the three most common triggers of anaphylaxis in Korean children, and anaphylaxis could occur at remarkably low levels of sIgE.

Hospitalizations due to allergic reactions in Finnish and Swedish children during 1999-2011

BACKGROUND

Several authors have reported on allergic reactions that resulted in presentation to the emergency department. However, studies of the secular trend of hospitalizations for paediatric allergic reactions, including anaphylaxis, are scarce. The aim of this study was to describe the secular trends of hospitalizations for allergic reactions, including anaphylaxis, among children aged 0-19 years in Finland and Sweden, and to establish the trend of prescribed epinephrine auto-injectors (EAI) among paediatric populations.

METHODS

Using national databases, we identified hospitalizations between 1999 and 2011 with the primary diagnosis of allergic reaction per International Classification of Diseases, 10th Revision.

RESULTS

Hospitalizations for allergic reactions totalled 1987 in Finland and 5433 in Sweden. Incidence rates increased in both countries. In Finland, the incidence of admission was 7.8 per 100 000 person-years at the start of the study period and 15.8 at the end of the study period. The corresponding numbers among Swedish children were 13.7 and 31.8 per 100 000 person-years. In Finland, 60% of children hospitalized were aged under 10 years. In Sweden, this proportion was somewhat lower, at 48%. Most hospitalizations occurred between May and September. The prevalence of EAI prescriptions in Finland increased by fourfold during the study period. In Sweden, such an increase was not identified.

CONCLUSIONS

The incidence of allergic reactions leading to hospitalizations between 1999 and 2011 increased in Finland and Sweden among children aged 0 to 19 years. In Finland, the incidence was lower throughout the study period compared to Sweden. Younger children constituted the majority of hospitalized children.

Emergency epinephrine use for food allergy reactions in Chicago Public Schools

BACKGROUND

Given the increase in childhood food allergy, national and local policies have been developed to encourage schools to stock undesignated epinephrine auto-injectors in case of an anaphylactic emergency.

PURPOSE

To describe the use of epinephrine auto-injectors in Chicago Public Schools during the 2012-2013 school year, specifically for food-induced allergic reactions.

METHODS

District-issued epinephrine auto-injectors were distributed to all public and charter schools in Chicago prior to the start of the 2012-2013 school year. Data on their use were collected, and frequencies were computed in the autumn of 2013.

RESULTS

Thirty-eight district-issued epinephrine auto-injectors were administered during the inaugural year of the Chicago Public Schools initiative. Epinephrine auto-injectors were administered to students (92.1%) and school staff (7.9%). Most district-issued epinephrine auto-injectors were administered in elementary schools (63.2%) and on Chicago's North-Northwest Side (36.8%). More than half (55.0%) of all district-issued epinephrine auto-injectors were administered for first-time anaphylactic events. Food-induced reactions accounted for more than half (55.3%) of all reactions requiring epinephrine auto-injector use, whereas the trigger of more than one third (34.2%) of all reactions requiring the use of an epinephrine auto-injector remained unknown.

CONCLUSIONS

Chicago Public Schools is the first large, urban school district in the U.S. to develop and implement the District-Issued Emergency Epinephrine Initiative, which helped 38 students and staff avoid potential morbidity and mortality. The impact of this initiative during its first year underscores the need for stocking undesignated epinephrine in schools across the country.

Caustic ingestions mimicking anaphylaxis: case studies and literature review

Anaphylaxis presents in children with rapid involvement of typically 2 or more organ systems including cutaneous, gastrointestinal, and respiratory. Caustic ingestions (CI) may also present with acute involvement of cutaneous, gastrointestinal, and respiratory systems. We present 2 cases of "missed diagnosis" that illustrate how CI presenting with respiratory symptoms can be mistaken for anaphylaxis owing to these similarities. Both of these patients had delay in appropriate care for CI as a result. These cases demonstrate the importance of considering CI in children who have gastrointestinal symptoms, respiratory distress, and oropharyngeal edema.

Identifying barriers to chronic disease reporting in Chicago Public Schools: a mixed-methods approach

BACKGROUND

Chronic disease among school-aged children is a public health concern, particularly for asthma and food allergy. In Chicago Public Schools (CPS), rates of asthma and food allergy among students are underreported. The aim of this study was to determine the barriers to chronic disease reporting as experienced by CPS parents and school nurses.

METHODS

A mixed-methods approach included focus groups and key informant interviews with parents and school nurses, and a cross-sectional survey was completed by parents. Qualitative data analysis was performed and survey data were analyzed to determine the significant demographic and knowledge variables associated with successfully completing the reporting process.

RESULTS

The three main barriers identified were 1) a lack of parental process knowledge; 2) limited communication from schools; and 3) insufficient availability of school nurses. Parents were significantly more likely to successfully complete the reporting process if they knew about special accommodations for chronic diseases, understood the need for physician verification, and/or knew the school nurse.

CONCLUSIONS

These findings suggest that increasing parental knowledge of the reporting process will allow schools to better identify and manage their students' chronic conditions. A parent-focused intervention informed by these results has been completed.