Impact of β-Lactam Allergies on Antimicrobial Selection in an Outpatient Setting

Qualitative analysis of healthcare provider perspectives to evaluating beta-lactam allergies

BACKGROUND

There is a lack of understanding of the barriers reported by healthcare providers when evaluating beta-lactam allergies, but knowledge of these barriers is required for practical and effective implementation interventions.

METHODS

Twenty-five healthcare providers, consisting of physicians, nurses and pharmacists practicing in the areas of intensive care, emergency medicine, infectious disease and general hospital practice, were interviewed between September 2021 and July 2023. Twenty-three of these providers were practising in the USA. A semi-structured interview guide grounded in the Theoretical Domain Framework was used for the interviews. Deductive and inductive analysis was performed on the interview transcripts, and translated into intervention recommendations using the Behaviour Change Wheel.

RESULTS

Widely held beliefs included a lack of clear policy for the evaluation of allergies, confusing or missing documentation of allergy information, confidence in their own and their colleagues' ability to evaluate allergies when information is available, and pharmacists as the provider most equipped to evaluate beta-lactam allergies.

CONCLUSIONS

Health systems should adopt and disseminate policies for the evaluation of beta-lactam allergies, and promote the use of pharmacists in the evaluation of drug allergies when possible. Allergy sections of electronic health records should be reworked to encourage unambiguous documentation of allergy reactions and support using previously tolerated beta-lactam antibiotics.

Challenges and opportunities related to penicillin allergy in the Veterans Health Administration: a narrative review

The presence of a penicillin allergy label in a patient's medical chart is associated with negative clinical and economic outcomes. Given that less than 10% of reported reactions are truly immunoglobulin E-mediated, removal of unverified penicillin allergy labels is a public health priority and an area of ongoing implementation research. The Veterans Health Administration (VHA) is the largest integrated healthcare system in the United States, with almost 9 million veterans currently enrolled. However, studies analyzing the impact of the penicillin allergy label in this population are limited to single facilities and largely focus on short-term outcomes of allergy documentation correction, usage of β-lactams, and avoidance of antibiotic-related side effects. Broader, national VHA studies focusing on health outcomes and costs are lacking. As with non-VHA facilities, penicillin allergy evaluations are limited owing to the absence of formal allergy/immunology services at most VHA facilities. Pharmacy-driven screening and referral for clinic-based penicillin skin testing is a promising and frequently discussed modality in the literature, but its scalability within the VHA is not yet proven. Broader, evidence-based strategies that can be adapted to the available resources of individual VHA facilities, including those without on-site access to allergy providers, are needed.

Implementation and Impact of a β-Lactam Allergy Assessment Protocol in a Veteran Population

Background

Approximately 10% of the US population reports having a β-lactam allergy, although nearly 90% do not have a true immunoglobulin E (IgE)-mediated reaction. This misconception results in using nonpreferred antibiotics, leading to antimicrobial resistance and treatment failure. To evaluate, clarify, and clear β-lactam allergies, we implemented a pharmacist-driven β-lactam allergy assessment (BLAA) protocol and penicillin allergy clinic (PAC). The purpose of this study was to illustrate the BLAA process, including the pharmacist-run PAC, and assess the impact on allergy clearance.

Methods

Clinical pharmacy specialists (CPS) evaluated hospitalized veterans with β-lactam allergies, using the BLAA protocol. Eligible patients could later be seen in PAC. This was a retrospective observational review of the BLAA protocol to assess recommendations for β-lactam antibiotic use and PAC outcomes.

Results

Between November 2017 and February 2020, 278 patients were evaluated, and 32 were seen in the clinic. The most common allergen was penicillin, and the most reported reaction was a rash (27%) or pruritus and urticaria (18%). Through PAC and the BLAA protocol, 86 patients (31%) were cleared for allergy removal, and 188 (68%) were cleared for alternative β-lactams. The evaluation revealed that 274 patients (99%) were eligible to receive a β-lactam antibiotic, and only 4 patients (1%) were recommended for avoidance of all β-lactams.

Conclusions

These findings highlight the utility of the pharmacist-driven BLAA protocol. We illustrated that most patients with documented β-lactam allergies were eligible for alternative β-lactams. The implementation of the BLAA protocol and pharmacist-run PAC facilitated allergy clearance and has the potential to promote alternative β-lactam use.