Anaphylaxis: incidence, presentation, causes and outcome in patients in a tertiary-care hospital in Karachi, Pakistan.

BACKGROUND Anaphylaxis is a potentially fatal condition requiring immediate resuscitation. Data regarding the epidemiology of anaphylaxis are limited and inconsistent. A reason for the variability was unavailability of a universally acceptable case definition till 2005. We reviewed cases using this new definition AIM To review the incidence, clinical presentation, cause and outcome of anaphylaxis at a tertiary-care centre in a low-income country. DESIGN Retrospective, case series METHODS Chart review of all patients discharged from Aga Khan University Hospital between January 1988 and December 2012 (24 years) with anaphylaxis definition as per second National Institute of Allergy and Infection disease/Food Allergy and Anaphylaxis Network Symposium RESULTS Total of 129 cases were found with mean age of 41.6 years (SD 18.8). Majority of patients had cutaneous features (76.7%), followed by respiratory (68.9%), cardiac (64.3%) and gastrointestinal (20.9%) symptoms, respectively. About 22.4% of patients had positive history for allergens out of which 31% (n = 9) were exposed to the same allergens. The common causes identified for anaphylaxis were drugs (60.5%), food (16.3%) and intravenous contrast (10.9%), respectively. Only 22.5% of cases received epinephrine as a part of their initial management. In four patients (3.1%) the cause of death was attributed to anaphylaxis. CONCLUSION Anaphylaxis is a rare but life-threatening condition. Though cutaneous features are most common, their absence does not exclude the diagnosis. Drugs were the most common cause and epinephrine was not commonly used as first-line agent for its management.