Identification of patients eligible for penicillin skin test protocol
Saturday, March 3, 2018
South Hall A2 (Convention Center)
Christine Muglia, MD, Sarah M. Abbassi, MD, Jasmine Huerta, Arun Mattappallil, PharmD, Reena Khianey, MD, Alan H. Wolff, MD, Eugenio Capitle, MD
RATIONALE: Removing penicillin allergy from patient charts via negative skin testing has been shown to result in use of narrower spectrum antibiotics, more effective antibiotics, and more cost-effective therapy. Penicillin skin testing is a valuable test in patients with history of IgE-mediated reactions. We sought to identify how many patients in our institution had prior IgE-mediated reaction to penicillin, thus would benefit from implementation of a penicillin skin test protocol in our institution.

METHODS: A retrospective cohort study of patients >18 years admitted during January-February 2017 with documented penicillin allergy was performed. Type of reaction was documented in the electronic medical record (EMR) as anaphylaxis, rash, itching, hives, swelling, shortness of breath, or a "free-texted" comment. We grouped the reactions as undocumented, possibly IgE-mediated (any combination of anaphylaxis/rash/itching/hives/swelling/shortness of breath), and non-IgE mediated (thrombocytopenia, anxiety, stomach upset, acute interstitial nephritis, etc).

RESULTS: Of 183 patients who met the inclusion criteria, 32% (n=58) reactions were undocumented, 61% (n=112) possibly IgE-mediated, and 7% (n=13) non-IgE mediated. By combining the undocumented and possibly IgE-mediated reactions, we identified 93% (n=170) of patients with penicillin allergy over a two month period who would likely benefit from penicillin skin testing.

CONCLUSIONS: These patients require a more detailed history prior to skin testing because EMR does not distinguish between Type 1-4 reactions. Nonetheless, we identified a significant number of penicillin-allergic patients with possibly IgE-mediated reaction or undocumented reaction who would benefit from the implementation of an institution-wide penicillin skin test protocol.