The changing face of anaphylaxis in adults and adolescents

Our institution has published serial studies of adults and adolescents with anaphylactic events. The first series was published in 1993 and the last was published in 2006. It was our perception that the nature of anaphylactic episodes had changed over the 2 decades since the last review.

To determine whether the etiologies and presentations of anaphylaxis have changed during the past decade in our population.

Patient charts were identified based on International Classification of Diseases, Ninth Revision codes for anaphylactic shock. Charts identified were analyzed for clinical symptoms reported, comorbidities, etiology, investigative testing, and subsequent treatment. These cases were categorized as definitive, probable, or idiopathic based on history and results from testing, similar to our prior reports.

We identified 281 possible cases, of which 218 met criteria for anaphylaxis. Of these cases, median age was 42 years (range 9-78) and 64% were female. In the review of cases, 85 (39%) were determined to have a definitive etiology, 57 were determined to have a probable etiology (26%), and 76 (35%) were idiopathic. Interestingly, of those with a definitive cause, the most common etiology identified was galactose-α-1,3-galactose, accounting for 28 cases (33%). Foods were the second leading cause, accounting for 24 cases (28%).

In this follow-up report on anaphylaxis etiology from a single center, the most common etiology was galactose-α-1,3-galactose. This differs greatly from prior reports from our center. Interestingly, the percentage of cases attributed to idiopathic anaphylaxis decreased from 59% in our previous report to 35% in the present report, which could largely be explained by the number of galactose-α-1,3-galactose cases.