44th Multicenter Airway Research Collaboration (MARC-44)

Carlos A. Camargo, Jr., MD, DrPH (Principal Investigator)
Lacey B. Robinson, MD MPH (Co-Investigator)
Anna Chen Arroyo, MD MPH (Co-Investigator)
Susan A. Rudders, MD MSc (Co-Investigator)
Ashley Sullivan, MPH, MS (Project Coordinator)

Funding Source: 
Funded by a grant from kaleo, Inc. to MGH (Carlos A. Camargo, PI). Kaleo, Inc. has no role in the conduct of the study nor collection, management, or analysis of data


  • Aim 1: To characterize trends in emergency department (ED) visits and hospitalizations for infant anaphylaxis over time and by region in the United States (US) from 2006-2015.
  • Aim 2: To quantify the rates and predictors of severe anaphylaxis, including hospitalization, intensive care unit (ICU) admission and ED revisits (after initial ED visit for anaphylaxis).
  • Aim 3: To quantify the cost of infant anaphylaxis including ED visits, inpatient hospitalization and ED revisits.

Design and Setting: We conducted retrospective cohort studies of the trends, health care utilization, and cost of anaphylaxis and other food-related acute allergic reactions in infants and toddlers (aged < 3 years) who presenting for ED care in the US from 2006-2015 using data from multiple large data sets available through the Healthcare Cost and Utilization Project (HCUP).

The study utilized four HCUP databases: Nationwide Emergency Department Sample (NEDS), Nation (Nationwide) Inpatient Sample (NIS), State Emergency Department Database (SEDD, New York and Nebraska), and State In-patient Database (SID, New York and Nebraska).

Study Population: We studied children (< 18 year of age) and infants and toddlers (age < 3 years) who presented to the ED or inpatient admission with a physician-diagnosed acute allergic reaction. By using different sets (and subsets) of diagnosis codes we identified anaphylaxis, overall acute allergic reactions (AAR), food-induced anaphylaxis (FIA) and overall food-induced acute allergic reactions (FAAR).