Epidemiology and management of acute angioedema across tertiary and district-level south african emergency rooms

INTRODUCTION A ngioedema (AE) is the most common acute allergic presentation in emergency rooms (ER), with hospitalisation rates increasing in high-income countries. AE can complicate with life-threatening laryngeal obstruction. There are no local data; therefore we aimed to characterise acute AE cases presenting to ER. METHOD We conducted a retrospective folder review of all patients admitted to Groote Schuur Hospital and Mitchells Plain District Hospital ER from 1 June 2018 to 30 June 2020. Patients >= 8 years that were coded T78.3/1 78.4 by the International Statistical Classification of Diseases and Related Health Problems 10th Revision (ICD10) were included in this cohort. The authors then reviewed each event and collected information regarding patient demographics, medical history, management and outcomes. RESULTS A total of 231 events were T78.3/4 by ICD10 coding. Of these, there were 149 (64.5%) events of acute AE. AE events had a median (IQR) age of 42 (27-58) years and 63% were female. Drug-induced AE was the most common cause, with 63/149 (42%) of the events linked to an offending drug. ACE-Inhibitors were the likely culprit in 41/63 (65%). A total of 68/149 (45.6%) cases were considered probably histamine-mediated (in only five events was there known allergen exposure). Ten patients were known to have hereditary angioedema (HAE). Twenty-two (14.8%) of the cases reported recurrent AE, with none known or referred to allergy services for investigation. The median (IQR) number of hours from onset to angioedema was 12 (5-24 hours). The majority of acute AE involved swelling above the shoulders (60%, 90/149), and there was airway involvement in 22 patients, with two needing intubation. Twenty-one patients were admitted, with 6 of them (28.6%) requiring an intensive care unit (ICU), with no deaths. Guideline acute management occurred in 83.2% of cases, with only two cases of HAE being treated incorrectly with antihistamines and corticosteroids. CONCLUSION AE is the most common allergy presentation to ER in Cape Town, South Africa, with 1-3 cases occurring per week. Bradykinin-mediated AE secondary to ACE-I therapy is the single most common offender. Ongoing awareness and system-strengthening is required to ensure accurate diagnosis of the less common causes of AE (particularly bradykinin-mediated AE) and linkage to allergy specialist services for recurrent AE.