title: ACE-I Angioedema: Accurate Clinical Diagnosis May Prevent Epinephrine-Induced Harm.
abstract: BACKGROUND
  Upper airway angioedema is a life-threatening emergency department (ED) presentation with increasing incidence. Angiotensin-converting enzyme inhibitor induced angioedema (AAE) is a non-mast cell mediated etiology of angioedema. Accurate diagnosis by clinical examination can optimize patient management and reduce morbidity from inappropriate treatment with epinephrine. The aim of this study is to describe the incidence of angioedema subtypes and the management of AAE. We evaluate the appropriateness of treatments and highlight preventable iatrogenic morbidity.
  
  
  METHODS
  We conducted a retrospective chart review of consecutive angioedema patients presenting to two tertiary care EDs between July 2007 and March 2012.
  
  
  RESULTS
  Of 1,702 medical records screened, 527 were included. The cause of angioedema was identified in 48.8% (n=257) of cases. The most common identifiable etiology was AAE (33.1%, n=85), with a 60.0% male predominance. The most common AAE management strategies included diphenhydramine (63.5%, n=54), corticosteroids (50.6%, n=43) and ranitidine (31.8%, n=27). Epinephrine was administered in 21.2% (n=18) of AAE patients, five of whom received repeated doses. Four AAE patients required admission (4.7%) and one required endotracheal intubation. Epinephrine induced morbidity in two patients, causing myocardial ischemia or dysrhythmia shortly after administration.
  
  
  CONCLUSIONS
  AAE is the most common identifiable etiology of angioedema and can be accurately diagnosed by physical examination. It is easily confused with anaphylaxis and mismanaged with antihistamines, corticosteroids and epinephrine. There is little physiologic rationale for epinephrine use in AAE and much risk. Improved clinical differentiation of mast cell and non-mast cell mediated angioedema can optimize patient management.
authors.affiliation: Queen's University, Departments of Emergency Medicine and Biomedical and Molecular Sciences, Kingston, Ontario, Canada; Western University, Division of Emergency Medicine, Department of Medicine, London, Ontario, Canada.
authors.forename: R Mason
authors.initials: RM
authors.lastname: Curtis
authors.affiliation: Queen's University, Division of Allergy and Immunology, Kingston, Ontario, Canada.
authors.forename: Sarah
authors.initials: S
authors.lastname: Felder
authors.affiliation: Queen's University, Division of Allergy and Immunology, Kingston, Ontario, Canada.
authors.forename: Rozita
authors.initials: R
authors.lastname: Borici-Mazi
authors.affiliation: Queen's University, Departments of Emergency Medicine and Biomedical and Molecular Sciences, Kingston, Ontario, Canada; Queen's University, Program in Critical Care Medicine, Kingston, Ontario, Canada; Western University, Division of Critical Care of Medicine, Department of Medicine, London, Ontario, Canada.
authors.forename: Ian
authors.initials: I
authors.lastname: Ball
mesh_terms: D000328:Adult; D000368:Aged; D000402:Airway Obstruction / Q000150:complications / Q000473:pathology*; D054179:Angioedemas, Hereditary / Q000175:diagnosis* / Q000209:etiology* / Q000473:pathology / Q000628:therapy; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000009:adverse effects*; D000075202:Contraindications; D004155:Diphenhydramine / Q000627:therapeutic use; D004636:Emergency Service, Hospital; D004837:Epinephrine / Q000009:adverse effects*; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D011899:Ranitidine / Q000627:therapeutic use; D012189:Retrospective Studies; D012307:Risk Factors
chemical_list: D000806:Angiotensin-Converting Enzyme Inhibitors; D011899:Ranitidine; D004155:Diphenhydramine; D004837:Epinephrine