For a study, researchers sought to better understand the demographic, clinical, and treatment characteristics of older persons who arrived at emergency departments (EDs) with anaphylaxis instead of less severe, non-anaphylactic acute allergic responses (AARs). Using the International Classification of Diseases, Ninth Revision (ICD-9) codes or ICD-9-based algorithms, including the National Institute of Allergy and Infectious Diseases (NIAID) diagnostic criteria, a retrospective analysis of ED patients older than or equal to 65 years was carried out. The features above were compared between cohorts using descriptive statistics. Among the 164 eligible visits, 71 (43.3%), 90 (54.9%), and 3 (1.8%) cases were found using the ICD-9 codes, the algorithms, or both. Only half of them met the NIAID diagnostic standards. Criteria-confirmed anaphylaxis group showed greater frequencies of food allergies (26.8%  vs. 12.2%, P=.02) but lower rates of medication allergies (43.9% vs. 61.0%, P=.03) as compared to the non-anaphylactic AAR group. The presenting signs and symptoms for the anaphylactic group that met the criteria were mucocutaneous, respiratory, cardiovascular, and gastrointestinal, in that order of decreasing frequency. Pre-ED (12.2% vs 0.0%, P=.001) or ED (72.0% vs 4.9%, P<.001) epinephrine administration, and allergy referral (17.1% vs 2.4%, P=.002) rates were greater in the group with criteria-confirmed anaphylaxis (13.4% vs 2.4%, P=.009). Tryptase levels were infrequently required; they were never ordered in the non-anaphylactic AAR group and just once in the group with criteria-confirmed anaphylaxis. Despite a low fatality rate (n=1), hospitalization was necessary for 64.6% of the anaphylactic cohort who met the criteria, with 23.2% hospitalized in an intensive care unit. Anaphylaxis in elderly ED patients was still poorly diagnosed. Using the current techniques, finding cases that meet the NIAID criteria was still difficult. Recommendations were not well followed in the management of these individuals.

Source – sciencedirect.com/science/article/abs/pii/S1081120622002113