Treatment of Patients with a History of Penicillin Allergy in a Large Tertiary-Care Academic Hospital

MedicalResearch.com Matthieu Picard, MD, FRCPC

Hôpital Maisonneuve-Rosemont
Université de Montréal Montréal, Qc, Canada

MedicalResearch.com: What are the main findings of the study?

Dr. Picard: We found that patients reporting a history of penicillin allergy were often treated with penicillins despite their history of allergic reaction to that drug.

In this study, which took place in a large tertiary-care academic hospital without allergists on staff, more than half of patients with a presumed penicillin allergy and a need for antibiotics were treated with beta-lactams, a class of antibiotics that includes penicillins and drugs that can cause allergic reactions in penicillin allergic individuals because of cross-reactivity.

Explanations for this situation can be found in the poor documentation of the history of penicillin allergy in the medical file, as shown by the frequent lack of important details regarding that history and the fact that it was not even mentioned at time of antibiotic prescription in 21% of cases.

Furthermore, very few files documented the decision-making process leading to the use of a penicillin and when it did, the rationale was frequently wrong. These findings clearly point to a lack of knowledge on the management of penicillin allergy and argue for increased education on that matter.

Importantly, most patients with a history of penicillin allergy are in fact not allergic and can receive it safely. However, the only way to safely determine the true allergic status of a patient regarding penicillin is through an evaluation by an allergist who can perform penicillin skin testing and drug challenges. In this study, only 2 of 134 patients with a history of penicillin allergy were referred to an allergist upon discharge to determine their allergic status towards penicillin.

In a parallel survey, physicians among the hospital staff said that their lack of knowledge on penicillin allergy and the absence of allergists on staff explained why they did not refer patients for penicillin allergy evaluation. The usefulness of a penicillin allergy evaluation cannot be overemphasized as it has been shown that patients with a history of penicillin allergy are often treated with second-choice antibiotics which are more expansive than their beta-lactam equivalent and have a broader spectrum of antimicrobial activity than needed. In this study, it was calculated that the use of alternative antibiotics carried an additional cost of $326.50 CAD per patient.

MedicalResearch.com: What should clinicians and patients take away from your report?

Dr. Picard: Physicians should refer patients with a history of penicillin allergy to an allergist to clarify their allergic status towards penicillin. This should be done ahead of need for antibiotics and especially for patients who are felt to be at risk of needing antibiotics in the near future. That being said, ideally every patient with a history of penicillin allergy should be evaluated by an allergist. On the other hand, patients with a history of penicillin allergy should inquire about penicillin allergy evaluation to their primary care physician. Also, it should encourage physicians not familiar with penicillin allergy to learn more on the subject as 10% of patients report a history of penicillin allergy making this situation very common in everyday medical practice.

MedicalResearch.com: What recommendations do you have for future research as a result of this study?

Dr. Picard: In the future, research should focus on ways to provide systematic penicillin allergy evaluation for patients at increased risk of needing antibiotics in the future. This way, the prevalence of a history of penicillin allergy could in theory be reduced and as a result the unnecessary use of alternative broad-spectrum antibiotics, with their associated costs and comorbidities, could hopefully be minimized. Also, measures should be put in place to insure that patients with an acute need for antibiotics be treated according to the current guidelines on penicillin allergy management.

Citation:

Treatment of Patients with a History of Penicillin Allergy in a Large Tertiary-Care Academic Hospital

Matthieu Picard, Philippe Bégin, Hugues Bouchard, Jonathan Cloutier, Jonathan Lacombe-Barrios, Jean Paradis, Anne Des Roches, Brian Laufer, Louis Paradis
The Journal of Allergy and Clinical Immunology: In Practice – 18 February 2013 (10.1016/j.jaip.2013.01.006)