Impact of a pharmacist-driven beta-lactam allergy interview on inpatient antimicrobial therapy: A pilot project

Risk Stratification of Penicillin Allergy Labeled Children: A Cross-Sectional Study from Jordan

Background

Implementing allergy testing among children with a reported history of penicillin allergy could be challenging, particularly in developing countries with limited resources. This study screened and risk-stratified the likelihood of true penicillin allergy among children labeled with penicillin allergy in Jordan.

Methods

A web-based survey, completed by parents, assessed history, type, and severity of penicillin allergic reactions, including age at diagnosis, symptoms, time to the reaction, reaction's course and resolution, and received medical evaluation/testing. Low-risk allergic symptoms were defined as vomiting, diarrhea, headache, dizziness, itching, rash, cough, or runny nose without evidence of anaphylaxis or severe cutaneous reactions.

Results

A total of 530 parents of "penicillin allergy"-labeled children completed the survey. Of these, 86.4% reported allergic reactions to penicillin and 13.6% reported avoidance of penicillin due to family history. Among the former, 52.2% were male, 67.3% were three years old or younger when the reported reaction was established, and 68.3% experienced exclusively low-risk symptoms. Overall, skin rash was the most reported symptom (86.0%). High-risk symptoms were reported in 31.5% of children. About two-thirds (64.0%) of children were reported to have experienced symptoms after the first exposure to penicillin. The most common indication for antibiotic use was a throat infection (63.8%). Asthma comorbidity was significantly higher among high-risk (24.8%) compared low-risk group (11.5%).

Conclusion

In Jordan, many parent-reported penicillin allergic reactions seem to be clinically insignificant and unlikely to be verifiable, which can adversely affect patients' care and antimicrobial stewardship. An appropriate clinical history/evaluation is a key step in identifying true immunoglobulin E-mediated allergic reactions and risk stratifying patients for either de-labeling those with obviously non-immune-mediated reactions or identifying candidates for direct oral challenge test.

Penicillin allergy de-labelling by non-allergists: a comparison of testing protocols

Optimizing penicillin allergy de-labelling (PADL) to ensure patients with an incorrect penicillin allergy record are de-labelled with minimal patient harm is important for antibiotic stewardship. The heterogeneity of inclusion and exclusion criteria in the published penicillin allergy testing protocols risks suboptimal delivery of PADL. We compared the similarities and the differences between non-allergist-delivered PADL testing protocols and make suggestions for harmonization. The observed variation in testing practice has two broad elements: (i) definitions and terminology; and (ii) differences in the acceptability of perceived risk. All direct drug provocation testing (DDPT) protocols included patients with benign delayed rash as eligible for testing, although the remoteness of the rash, and the terminology used to describe the rash, differed. Patients with features of potential IgE reactions were excluded from most DDPT protocols, but not all of them. There was differing advice on how to manage patients who had subsequently tolerated penicillin since the index reaction and differences in which patients were considered ineligible for DDPT due to acuity of illness, comorbidities and concomitant medications. Standardization of the terminology used in penicillin allergy testing protocols and consensus on inclusion and exclusion criteria are required for safe and efficient PADL delivery at scale by non-allergists.

The Burden of Self-Reported Antibiotic Allergies in Health Care and How to Address It: A Systematic Review of the Evidence

BACKGROUND

Antibiotics are the first-line treatment for bacterial infections; however, overuse and inappropriate prescribing have made antibiotics less effective with increased antimicrobial resistance. Unconfirmed reported antibiotic allergy labels create a significant barrier to optimal antimicrobial stewardship in health care, with clinical and economic implications.

OBJECTIVE

A systematic review was conducted to summarize the impact of patient-reported antibiotic allergy on clinical outcomes and various strategies that have been employed to effectively assess and remove these allergy labels, improving patient care.

METHODS

The review was undertaken using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. A critical appraisal was conducted on all studies and a narrative synthesis was performed to identify themes.

RESULTS

Four themes emerged: the prevalence of antibiotic allergy, impact of antibiotic allergy on antimicrobial prescribing, impact of antibiotic allergy on clinical outcomes, and delabeling strategies to improve clinical outcomes. Of the 32 studies, including 1,089,675 participants, the prevalence of reported antibiotic allergy was between 5% and 35%. Patients with a reported antibiotic allergy had poorer concordance with prescribing guidelines in 30% to 60% of cases, with a higher use of alternatives such as quinolone, tetracycline, macrolide, lincosamide, and carbapenem and lower use of beta-lactam antibiotics. Antibiotic allergy delabeling was identified as an intervention and recommendation to advance the state of the science.

CONCLUSIONS

There is substantial evidence within the literature that antibiotic allergy labels significantly impact patient clinical outcomes and a consensus that systematic assessment of reported antibiotic allergies, commonly referred to as delabeling, improves the clinical management of patients.

The effectiveness of interventions that support penicillin allergy assessment and delabeling of adult and pediatric patients by nonallergy specialists: a systematic review and meta-analysis

OBJECTIVES

Penicillin allergy records are often incorrect and may result in harm. We aimed to systematically review the effectiveness and safety of nonallergist health care worker delivery of penicillin allergy delabeling.

METHODS

We searched EMBASE/MEDLINE/CINAHL (Ovid), PsycInfo, Web of Science, and Cochrane CENTRAL from inception to January 21, 2022 and unpublished studies and gray literature. The proportion of patients allergic to penicillin delabeled and harmed was calculated using random-effects models.

RESULTS

Overall, 5019 patients were delabeled. Using allergy history alone, 14% (95% confidence interval [CI], 9-21%) of 4350 assessed patients were delabeled without reported harm. Direct drug provocation testing resulted in delabeling in 27% (95% CI, 18-37%) of 4207 assessed patients. Of the 1373 patients tested, 98% were delabeled (95% CI, 97-99%), and nonserious harm was reported in 1% (95% CI, 0-2%). Using skin testing, followed by drug provocation testing, 41% (95% CI, 24-59%) of 2890 assessed patients were delabeled. Of the 1294 tested patients, 95.0% (95% CI, 90-99%) were delabeled, and the reported harm was low (0%; (95% CI 0-1%).

CONCLUSION

Penicillin allergy delabeling by nonallergists is efficacious and safe. The proportion of assessed patients who can be delabeled increases with the complexity of testing method, but substantial numbers can be delabeled without skin testing.

Usability of Graphical User Interfaces With Semiautomatic Delabeling Feature to Improve Drug Allergy Documentation

BACKGROUND

The quality of allergy documentation in electronic health records is frequently poor.

OBJECTIVE

To compare the usability of 3 graphical user interfaces (GUIs) for drug allergy documentation.

METHODS

Physicians tested 3 GUIs by means of 5 fictional drug allergy scenarios: the current GUI (GUI 0), using mainly free-text, and 2 new coded versions (GUI 1 and GUI 2) asking information on allergen category, specific allergen, symptom(s), symptom onset, timing of initial reaction, and diagnosis status with a semiautomatic delabeling feature. Satisfaction was measured by the System Usability Scale questionnaire, efficiency by time to complete the tasks, and effectiveness by a task completion score. Posttest interviews provided more in-depth qualitative feedback.

RESULTS

Thirty physicians from 7 different medical specialties and with varying degrees of experience participated. The mean System Usability Scale scores for GUI 1 (77.25, adjective rating "Good") and GUI 2 (78.42, adjective rating "Good") were significantly higher than for GUI 0 (56.58, adjective rating "OK") (Z, 6.27, P_adj < .001 and Z, 6.62, P_adj < .001, respectively). There was no significant difference in task time between GUIs. Task completion scores of GUI 1 and GUI 2 were higher than for GUI 0 (Z, 9.59, P_adj < .001 and Z, 11.87, P_adj < .001, respectively). Quantitative and qualitative findings were combined to propose a GUI 3 with high usability.

CONCLUSIONS

The usability and quality of allergy documentation was higher for the newly developed coded GUIs with a semiautomatic delabeling feature without being more time-consuming.

Follow-up of penicillin allergy labels 1 year after successful penicillin delabeling

BACKGROUND

Penicillin allergy delabeling confers many benefits, including reduced patient morbidity and mortality and improved health economics. Reports suggest that both patients and clinicians often remain hesitant to take and prescribe penicillins, respectively, after penicillin delabeling. However, follow-up of an individual's penicillin allergy label and incorporation of this into relevant health care records after delabeling have not been well studied in the Australian population.

OBJECTIVE

To evaluate the status of penicillin allergy labels in the community 1 year after penicillin delabeling at a tertiary hospital in Australia.

METHODS

A cross-sectional study was performed using follow-up interviews with patients and community primary care providers after 1 year from the date of patients' penicillin delabeling at a tertiary hospital in New South Wales, Australia. The main outcome measures that were evaluated included patient willingness to accept penicillin for future infections, patient self-reported receipt of penicillin-based antibiotics after delabeling, accuracy of penicillin allergy labels in the records of the primary care provider, and prescription of penicillin-based antibiotics by the general practitioner.

RESULTS

A total of 86 patients were included in this study. The percentage of patients with a correct penicillin allergy status at 1-year follow-up was 94% in the hospital electronic medical record but only 37% in primary care records. At 1-year follow-up, 14% of delabeled patients continued to reject penicillin prescriptions.

CONCLUSION

Better strategies are required to increase patient confidence in receiving penicillins after penicillin delabeling and to ensure that penicillin allergy labels are translated into the medical records at the primary care level.

The Use of Electronic Health Records to Study Drug-Induced Hypersensitivity Reactions from 2000 to 2021: A Systematic Review

Electronic health records (EHRs) have revolutionized the field of drug hypersensitivity reaction (DHR) research. In this systematic review, we assessed 140 articles from 2000-2021, classifying them under six themes: observational studies (n=61), clinical documentation (n=27), case management (n=22), clinical decision support (CDS) (n=18), case identification (n=9), and genetic studies (n=3). EHRs provide convenient access to millions of medical records, facilitating epidemiological studies of DHRs. Though the goal of CDS is to promote safe drug prescribing, allergy alerts must be designed and used in a way that supports this effort. Ultimately, accurate allergy documentation is essential for DHR prevention.

Instruction and Simulation to Improve Pharmacy Students' Knowledge and Confidence Regarding Assessment of Penicillin Allergies

Objective. To evaluate pharmacy students' knowledge of and confidence regarding penicillin allergy assessment and skin testing (PAAST) before and after a focused didactic instruction and simulation (FDIS).Methods. A multicenter, quasi-experimental, cross-sectional survey study was performed among pharmacy students before and after FDIS on PAAST at two schools of pharmacy. The FDIS on PAAST consisted of an infectious disease faculty-led seminar, student-led penicillin allergy counseling interviews, penicillin skin testing simulation, and case studies to assess penicillin allergy scenarios and management. An anonymous, voluntary, electronic survey was distributed to students (n=159) before and after the FDIS. The pre- and post-intervention survey contained 10 PAAST knowledge-based questions and multi-step, five-point Likert scale statements related to students' confidence in PAAST. The post-intervention survey also evaluated students' perceptions of the FDIS on PAAST. Descriptive statistics were performed, and the Student t test was used to compare pre- and post-intervention responses.Results. One hundred forty-three surveys were completed, resulting in a survey response rate of 90%. Students' PAAST knowledge scores (mean±SD) increased overall following the FDIS on PAAST (6.67±1.51 vs 7.81±1.39). Knowledge scores increased considerably for questions related to penicillin allergy consequences, cross-reactivity, and correct steps of PAAST. Pharmacy students' PAAST confidence scores (mean±SD) also improved following the interactive instruction and simulation (2.30±0.7 vs 3.22±0.67) with considerable confidence increases in penicillin skin testing. Pharmacy students' perceptions of the FDIS on PAAST were also positive overall.Conclusion. Pharmacy students' knowledge and confidence of PAAST improved following FDIS. This may be an effective strategy to implement PAAST education during pharmacy school.

Drug Allergy Delabeling Programs: Recent Strategies and Targeted Populations

Drug allergy delabeling programs have become an essential element of antibiotic stewardship. Development of delabeling programs involves careful selection of target patient population, thoughtful design of delabeling approach, stakeholder engagement, assembly of key team members, implementation, and evaluation of clinical and safety outcomes. Recent programs have targeted patients thought to be most likely to benefit from removal of inaccurate antibiotic allergy labels, those with β-lactam antibiotic allergies and high-risk populations likely to need β-lactam antibiotics as first-line treatment. This review provides an overview of current risk stratification methods and β-lactam cross-reactivity data and summarizes how different inpatient and outpatient delabeling programs have used these concepts in delabeling algorithms. β-Lactam delabeling programs for inpatients, pediatric patients, and programs utilizing telehealth have been implemented with good outcomes. This review also focuses on delabeling programs for high-risk populations likely to benefit from first-line β-lactam antibiotics. These populations include perioperative, prenatal, and immunocompromised patients. Delabeling programs have been successful in the inpatient and outpatient settings at enabling appropriate antibiotic use. This article reviews delabeling strategies utilized by these programs with a focus on highlighting elements key to their success and future areas for innovation.

The effects of beta-lactam allergy relabeling on antibiotic prescribing practices

BACKGROUND

Beta-lactam antibiotic allergy labels are highly prevalent but rarely indicate an allergic intolerance. These patient-reported allergies lead to broad-spectrum antibiotic use, conferred resistance, increased expense, and adverse effects.

OBJECTIVE

To implement and assess the impact of a history-based clinical guideline that directs antibiotic management and beta-lactam allergy relabeling for patients reporting beta-lactam allergies.

METHODS

Patients with beta-lactam allergy labels were identified by our trained multidisciplinary team in diverse clinical settings. This quality improvement project was conducted to evaluate the safety and impact of the guideline on antibiotic use by comparing prescribing practices before and after guideline implementation.

RESULTS

A total of 79 patients with beta-lactam allergies were identified (penicillins-90%, cephalosporins-10%). After guideline implementation, outcomes of allergy relabeling included the following: (1) complete removal, indicating an unlikely true allergy (27%); (2) updated to detail successfully tolerated beta-lactam courses (48%); or (3) no change made to current label (25%). Beta-lactam antibiotic courses before and after guideline implementation compared with total antibiotic courses: allergy removed (44% vs 70%; P < .001), allergy updated (32% vs 68%; P < .001), and no change (27% vs 41%; P = .08). Compared with before guideline implementation, beta-lactam antibiotics were 3 times more likely to be prescribed after allergy assessment (odds ratio, 3.22; 95% confidence interval, 2.4-4.3; P < .05).

CONCLUSION

The implementation of the beta-lactam allergy clinical guideline resulted in most patients' allergy labels being removed or advantageously updated. These allergy label changes correlated with a substantial increase in the percentage of beta-lactam antibiotics prescribed. After guideline implementation, beta-lactam antibiotics had a 3-fold increased odds of being prescribed independent of allergy label outcome.

Effectiveness of interventions that support penicillin allergy assessment and de-labelling of patients by non-allergy specialists: a systematic review protocol

OBJECTIVE

This review will systematically examine and synthesize the evidence evaluating the effectiveness and safety of interventions that enable non-allergy specialist health care workers to assess allergy risk in patients with reported penicillin allergies and subsequently remove erroneous allergy records.

INTRODUCTION

The potential benefits of removing erroneous penicillin allergy labels (de-labeling) are wide-ranging. Penicillin allergy assessment and de-labeling is an antibiotic stewardship priority. Delivery of such assessment and de-labeling by non-allergy specialists has been reported in several studies, but the effectiveness and safety have not been formally synthesized. This is a necessary step in the upscaling of penicillin allergy assessment services.

INCLUSION CRITERIA

This review will consider quantitative studies using appropriate designs. The studies will include adults and pediatric patients who have undergone penicillin allergy assessment and de-labeling by non-allergy specialists in any health care setting.

METHODS

A range of databases will be searched to identify studies published in English, with no date limit. Unpublished studies and gray literature will also be searched. Title and abstract screening, and assessment of selected full texts against the inclusion criteria will be conducted by at least two independent reviewers. Identified studies will be assessed for methodological quality using standardized critical appraisal instruments. Data will be extracted and categorized using the EPOC taxonomy, and the effectiveness and safety of the intervention will be determined. Where possible, data will be pooled to facilitate meta-analysis. Data from heterogeneous studies will be reported narratively. The GRADE approach for grading the certainty of evidence will be followed.

SYSTEMATIC REVIEW REGISTRATION NUMBER

PROSPERO CRD42020219044.

Harmonizing allergy care-integrated care pathways and multidisciplinary approaches

There is a wide time gap between the publication of evidence and the application of new knowledge into routine clinical practice. The consequence is sub-optimal outcomes, particularly concerning for long-term relapsing/remitting conditions such as allergic diseases. In response, there has been a proliferation of published guidelines which systematically review evidence for the gold-standard management of most allergic disorders. However, this has not necessarily been followed by improved outcomes, partly due to a lack of coordination across the patient pathway. This has become known as the "second translational gap". A proposed solution is the development and implementation of integrated care pathways (ICPs) to optimize patient outcomes, with the notion that evidence-based medicine requires evidence-based implementation. ICP implementation is shown to improve short-term outcomes for acute conditions and routine surgery, including reduced length of hospital stay, improved documentation and improved patient safety. However, this improvement is not reflected in patient experience or patient-centered functional outcomes. The implementation of life-long, cost-effective interventions within comprehensive pathways requires a deep appreciation for complexity within allergy care. We promote an evidence-based methodology for the implementation of ICPs for allergic disorders in which all stakeholders in allergy care are positioned equally and encouraged to contribute, particularly patients and their caregivers. This evidence-based process commences with scoping the unmet needs, followed by stakeholder mapping. All stakeholders are invited to meetings to develop a common vision and mission through the generation of action/effect diagrams which helps build concordance across the agencies. Dividing the interventions into achievable steps and reviewing with plan/do/study/act cycles will gradually modify the pathway to achieve the best outcomes. While the management guidelines provide the core knowledge, the key component of implementation involves education, training, and support of all healthcare professionals (HCPs), patients and their caregivers. The pathways should define the level of competence required for each clinical task. It may be useful to leave the setting of care delivery or the specific HCP involved undefined to account for variable patterns of health service delivery as well as local socioeconomic, ethnic, environmental, and political imperatives. In all cases, where competence is exceeded, it is necessary to refer to the next stage in the pathway. The success and sustainability of ICPs would ideally be judged by patient experience, health outcomes, and health economics. We provide examples of successful programs, most notably from Finland, but recommend that further research is required in diverse settings to optimize outcomes worldwide.

Overview of Beta-Lactam Allergy and the Role of the Pharmacist in Management

Unverified beta-lactam allergies are a substantial public health problem, as the majority of patients labeled as beta-lactam allergic do not have clinically significant allergies that may hinder the use beta-lactam therapy when indicated. Outdated or inaccurate beta-lactam or penicillin allergies can result in serious consequences, including suboptimal antibiotic therapy, increased risk of adverse effects, and use of broader spectrum antibiotics than indicated, which may contribute to antimicrobial resistance. The purpose of this review is to provide an overview of beta-lactam allergy and highlight the role of pharmacists in managing beta-lactam allergies. Studies have shown that pharmacists can play a vital role in allergy assessment, penicillin skin testing, beta-lactam desensitization, evaluation of beta-lactam cross-reactivity and recommending appropriate antibiotic therapy in patients with beta-lactam allergies.

Management of penicillin allergy in primary care: a qualitative study with patients and primary care physicians

Background

Six percent of patients are allergic to penicillin according to their medical records. While this designation protects a small number of truly allergic patients from serious reactions, those who are incorrectly labelled may be denied access to recommended first line treatment for many infections. Removal of incorrect penicillin allergy may have positive health consequences for the individual and the general population.

We aimed to explore primary care physicians’ (PCPs) and patients’ views and understanding of penicillin allergy with a focus on clinical management of infections in the face of a penicillin allergy record.

Methods

We conducted an interview study with 31 patients with a penicillin allergy record, and 19 PCPs in the North of England. Data were analysed thematically.

Results

Patients made sense of their allergy status by considering the timing and severity of symptoms. Diagnosis of penicillin allergy was reported to be ‘imperfect’ with PCPs relying on patient reports and incomplete medical records. PCPs and patients often suspected that an allergy record was incorrect, but PCPs were reluctant to change records. PCPs had limited knowledge of allergy services. PCPs often prescribed alternative antibiotics which were easy to identify. Both patients and PCPs differed in the extent to which they were aware of the negative consequences of incorrect penicillin allergy records, their relevance and importance to their lives, and management of penicillin allergy.

Conclusions

PCPs and patients appear insufficiently aware of potential harms associated with incorrect penicillin allergy records. Some of the problems experienced by PCPs could be reduced by ensuring the details of newly diagnosed reactions to antibiotics are clearly documented. In order for PCPs to overturn more incorrect penicillin records through appropriate use of allergy services, more information and training about these services will be needed.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12875-021-01465-1.

Assessing Use of a Standardized Allergy History Questionnaire for Patients with Reported Allergy to Penicillin

BACKGROUND

Inappropriate allergy labelling is associated with significant clinical and pharmacoeconomic implications. Detailed antimicrobial allergy assessments represent a key component of antimicrobial stewardship and aid in identifying true type I (immediate hypersensitivity) reactions. The allergy history form currently used at the University Hospital of Northern British Columbia (UHNBC), in Prince George, relies on the assessor's ability to ask appropriate prompting questions to obtain a thorough history, but it may not be sufficient to accurately identify true allergies.

OBJECTIVE

To compare a standardized allergy history questionnaire and the current allergy history form in terms of the quality and quantity of documentation gathered.

METHODS

This prospective observational study involved patients who were admitted to medical and surgical services at UHNBC from November 2018 to January 2019 with a penicillin-class allergy reported on their electronic medical record (EMR). A list of patients with EMR-reported allergies was generated by the hospital's health information software system, and these patients were interviewed using the standardized allergy history questionnaire.

RESULTS

A total of 48 patients were assessed during the study period. Nineteen (40%) of the patients had an inappropriate allergy label on their EMR. Only 36 (75%) had an allergic reaction described on their EMR. Furthermore, only 36 (75%) of the 48 patients had the same allergy recorded on the EMR and on the allergy history form contained in their paper chart, of whom 22 had a documented reaction. The mean time to complete the standardized allergy history questionnaire was 2 minutes.

CONCLUSIONS

At the study institution, documentation of allergy histories was often incomplete. Detailed allergy assessments are the first step in identifying true immunoglobulin E-mediated hypersensitivity reactions. Utilization of a standardized allergy history questionnaire is feasible and may serve to improve documentation and overall antimicrobial stewardship.

Impact of a structured interview on beta-lactam reaction documentation quality

Incomplete documentation of β-lactam reactions often leads to inappropriate antibiotic prescribing. The objective of this study was to evaluate the impact of a structured interview on the quality of β-lactam reaction documentation. After 203 interviews, documentation of the core components of a β-lactam reaction improved (48% vs 1%; P < .001).

Implementation of a pharmacist-led penicillin allergy de-labelling service in a public hospital

BACKGROUND

Inaccurate allergy labelling results in inappropriate antimicrobial management of the patient, which may affect clinical outcome, increase the risk of adverse events and increase costs. Inappropriate use of alternative antibiotics has implications for antimicrobial stewardship programmes and microbial resistance.

METHODS

All adult inpatients labelled as penicillin allergic were identified and screened for eligibility by the study pharmacist. An accurate allergy and medication history was taken. Patients were 'de-labelled', underwent oral challenge or were referred to an immunology clinic, if study criteria were met. All patients included in the study were followed-up 1 year after intervention.

RESULTS

Two hundred and fifty eligible patients with a label of 'penicillin allergy' were identified. The prevalence of reported penicillin allergy at Middlemore Hospital was 11%. We found that 80% of study patients could be 'de-labelled'. Of those, 80% were 'de-labelled' after an interview with the pharmacist alone, 16% had an uneventful oral challenge and 4% were deemed to be inappropriately labelled after referral to an immunology clinic. Appropriately labelled patients accounted for 20% of the study population. Changes to inpatient antibiotic therapy were recommended in 61% of 'de-labelled' patients, of which no patients had adverse events after commencing on penicillin antibiotics. At the 1 year follow-up, 98% of patients who were 'de-labelled' had no adverse events to repeated administration of penicillin antibiotics.

CONCLUSIONS

This study showed that a pharmacist-led allergy management service is a safe option to promote antimicrobial stewardship and appropriate allergy labelling.

Hospital Infection Control: Clostridioides difficile

Clostridioides difficile remains a leading cause of healthcare-associated infection. Efforts at C. difficile prevention have been hampered by an increasingly complex understanding of transmission patterns and a high degree of heterogeneity among existing studies. Effective prevention of C. difficile infection requires multimodal interventions, including contact precautions, hand hygiene with soap and water, effective environmental cleaning, use of sporicidal cleaning agents, and antimicrobial stewardship. Roles for probiotics, avoidance of proton pump inhibitors, and isolation of asymptomatic carriers remain poorly defined.

Is a Reported Penicillin Allergy Sufficient Grounds to Forgo the Multidimensional Antimicrobial Benefits of β-Lactam Antibiotics?

The majority of patients with reported penicillin allergy are not allergic when tested or challenged. Penicillin allergy testing has been shown to significantly reduce annual healthcare expenditures. Data have emerged showing β-lactams have multidimensional antibacterial effects in vivo, far beyond what is appreciated in standard bacteriological susceptibility testing media. These include enhancing bacterial killing by the innate immune system. Supporting the clinical relevance of these secondary underappreciated effects are recent clinical and pharmacoeconomic analyses that show worse outcomes in patients with reported penicillin allergies who receive non-β-lactam antibiotics when compared to their non-penicillin-allergic counterparts. This is particularly relevant in the treatment of Staphylococcus aureus bacteremia. This article reviews the tremendous advantages offered by β-lactam therapy and makes a strong case that the debunking of false penicillin allergies through a detailed allergy history and penicillin allergy testing should be a vital component of antimicrobial stewardship practices.

Penicillin allergy: a practical approach to assessment and prescribing

Penicillin allergies are not always lifelong. Approximately 50% are lost over five years

A reaction to penicillin during a childhood infection is unlikely to be a true allergy

Only 1–2% of patients with a confirmed penicillin allergy have an allergy to cephalosporins. In patients with a low risk of severe allergic reactions, cephalosporins are a relatively safe treatment option

Patients with a history of delayed non-severe reactions, such as mild childhood rashes that occurred over 10 years ago, may be suitable for an oral rechallenge with low-dose penicillin. This should be done in a supervised hospital environment

In many cases, with appropriate assessment and allergy testing, it may be possible to remove the penicillin allergy label

Implementation of a Pharmacist-Driven Detailed Penicillin Allergy Interview

Background: Self-reported penicillin allergies may be outdated or inaccurate, leading to the use of alternative antimicrobials that may be less effective, more toxic, and/or more expensive. Although penicillin skin tests can provide accurate assessments of penicillin allergies, these procedures are not feasible at all institutions. Another solution is to conduct a detailed penicillin allergy interview (DPAI), which can potentially lead to optimization of antimicrobial therapy. Objective: The purpose of this study was to assess the impact of a pharmacist-driven DPAI protocol. The primary objective was to measure the number of patients requiring a change to their allergy profile following DPAI. Secondary objectives included characterizing allergy profile updates and measuring the number of recommendations to switch to a β-lactam agent, provider acceptance rate, and patient tolerance. Methods: Standardized pharmacist-driven DPAIs were conducted prospectively on adult patients admitted with a documented penicillin allergy. The allergy profile within the electronic health record (EHR) was updated and a recommendation to switch to noncarbapenem β-lactam therapy was made when indicated by a decision algorithm. Results: A total of 175 (37.5%) patients received a DPAI. Of these, 133 (76.0%) required a change to their allergy profile. Additionally, 135 (77.1%) patients interviewed were on antimicrobial therapy, with 42 (31.1%) meeting criteria to switch to noncarbapenem β-lactam therapy; of which 31 (73.8%) patients were successfully transitioned, with no signs or symptoms of intolerance. Conclusions and Relevance: Implementation of pharmacist-driven DPAIs can provide updated and corrected allergy information within the EHR, allowing for de-escalation and/or optimization of antimicrobial therapy.

A UK hospital survey to explore healthcare professional views and attitudes to patients incorrectly labelled as penicillin allergic: an antibiotic stewardship patient safety project

OBJECTIVES

To ascertain the views, beliefs and attitudes of hospital staff to incorrect penicillin allergy records in order to determine healthcare worker motivation for the implementation of a penicillin de-labelling antibiotic stewardship intervention at the study hospital.

METHODS

An electronic questionnaire (SurveyMonkey) was distributed to medical, nursing and pharmacy staff at a 750-bed teaching district general hospital with no specialist allergy service.

RESULTS

193 staff responded (58% medical, 31% nursing and 11% pharmacy). Virtually all staff had encountered patients who believed themselves to be penicillin allergic, but felt the patient's belief to be erroneous. The potential negative consequences of an incorrectly assigned penicillin allergy label were acknowledged by the majority of respondents. In total, 188/190 (99%) of staff thought patients having an incorrect allergy status to penicillin was a problem and required a solution. Staff reported they would feel confident using a validated evidence-based question tool to de-label patients incorrectly labelled as penicillin allergic if the process was supported by Trust management, although many still felt apprehensive about de-labelling patients for fear of patient harm through inappropriate de-labelling.

CONCLUSIONS

A penicillin allergy de-labelling intervention would be well supported by healthcare workers at the study hospital, demonstrating a receptive environment for this behavioural change intervention. Further exploration of the barriers and levers to introducing an intervention is required using behavioural change methodology in order to design a successful de-labelling intervention.

Penicillin allergy skin testing as an antibiotic stewardship intervention reduces alternative antibiotic exposures in hematopoietic stem cell transplant recipients

BACKGROUND

Antibiotic allergy de-labeling using penicillin allergy skin testing (PAST) can reduce the use and cost of alternative, non-β-lactam antibiotics in general inpatient populations. This strategy's role in hematopoietic stem cell transplant (HSCT) recipients is unclear.

METHODS

This study aimed to determine the effect of a pre-transplant PAST protocol on antibiotic use, days of therapy (DOT), and cost in an immunocompromised population at a single center from 7/1/2010-2/1/2019. Patients who received chimeric antigen receptor (CAR) T-cell therapy and those who underwent transplantation in the outpatient setting were excluded.

RESULTS

Of 1560 patients who underwent inpatient HSCT during the study period, 208 reported β-lactam allergy (136/844 [16%] pre- and 72/716 [10%] post-implementation; P < .001). PAST was performed on 7% and 54% of HSCT recipients pre- and post-implementation, respectively. Only two positive PAST were noted. There were no adverse reactions to PAST. There were no significant differences in the disease and transplant characteristics between the two groups. Days of therapy and cost of alternative antibiotics significantly decreased post-implementation (mean 788 vs 627 days, P = .01; mean $24 425 vs $17 518, P = .009).

CONCLUSION

Penicillin allergy skin testing adjudicates reported β-lactam allergy in HSCT recipients, lowering use, DOT, and cost of alternative antibiotics and promoting effective formulary agents to treat immunocompromised HSCT recipients.

Allergic Reactions and Cross-Reactivity Potential with Beta-Lactamase Inhibitors

Although beta-lactam allergies are an emerging focus of stewardship programs and interventions, less is publicly released regarding allergies to beta-lactamase inhibitors. This review presents and evaluates the data regarding allergic reactions with beta-lactamase inhibitors. Clavulanate, sulbactam, and tazobactam are beta-lactam-based beta-lactamase inhibitors that are combined with several penicillins or cephalosporins in order to preserve antimicrobial activity in the presence of beta-lactamases. Avibactam, relebactam, and vaborbactam are non-beta-lactam beta-lactamase inhibitors that are combined with cephalosporins or carbapenems in order to expand the antimicrobial activity against broader-spectrum beta-lactamases. Case reports document hypersensitivity reactions to clavulanate, sulbactam, and tazobactam, but not to avibactam, relebactam, or vaborbactam. Based on these reports and considering the chemical structures, cross-allergenicity with beta-lactams is likely with sulbactam and tazobactam. Considering the slightly altered beta-lactam structure, cross-allergenicity is less likely with clavulanate, but still possible. It appears that cross-allergenicity between beta-lactam antimicrobials and the newer, non-beta-lactam beta-lactamase inhibitors is unlikely. It is important for clinicians to perform allergy testing to both the beta-lactam and the beta-lactamase inhibitor in order to confirm the specific allergy and reaction type.

Strategies for Clarifying Penicillin Allergies When Skin Testing Is Not an Option

Patients with reported penicillin allergies have been proven to experience negative health consequences, such as increased cost, suboptimal antimicrobial therapy, and adverse reactions. Though skin testing has been proposed as a method to clarify penicillin allergies, many institutions may lack the resources to perform skin testing on a wide scale. This literature review describes the current literature surrounding the use of penicillin allergy interviews when skin testing is not an option. Specifically, the review highlights the steps in carrying out a successful antibiotic allergy patient interview, summarizes the clinical evidence surrounding antibiotic allergy clarifications, and addresses key advantages and disadvantages of clarifying antibiotic allergies without the availability of skin testing.

Focus group study exploring the issues and the solutions to incorrect penicillin allergy-labelled patients: an antibiotic stewardship patient safety initiative

OBJECTIVES

Approximately 10% of the general population are reported to have a penicillin allergy, but more than 90% of these patients are able to tolerate penicillins after formal assessment. Patients with penicillin allergy labels have poorer health outcomes and incorrect labels impact negatively on healthcare systems. Identifying patients with incorrect penicillin allergy labels (those who can safely take penicillin) has the potential to benefit patients and healthcare systems. This study explores barriers and enablers towards identifying and removing incorrect penicillin allergy labels in inpatients ('delabelling').

METHODS

Two focus groups were completed with a total of 17 doctors, nurses and pharmacists at a 750-bed district general hospital in England.

RESULTS

Thematic analysis identified four main themes: managing penicillin allergic patients, environmental barriers, education for patients and staff and a future delabelling process. Staff reported that identifying and delabelling incorrect penicillin allergy records was a complex task and not a priority during the acute presentation. Participants felt confident removing erroneous allergy records if the patient was able to describe the reaction. Balancing time to confirm and delabel with competing duties was felt to be a challenge. Revisiting the discussion with the patient when time was less pressured was offered as a solution to the problem. The lack of provision to translate uncertainty about allergy status in the electronic health record was mentioned as a barrier to accurate documentation of allergy history. Ensuring all patient records were amended to reflect the new allergy status was identified as a challenge. A delabelling process involving nurses, doctors and pharmacist was discussed.

CONCLUSIONS

Delabelling patients with erroneous penicillin allergy labels was recognised as a complex problem. A patient pathway involving nurses, doctors and pharmacist is likely to be the optimal method to safely delabel patients.

Pharmacy-Led β-Lactam Allergy Interview (BLAI) Reduces Duration of Fluoroquinolones Within a Community Hospital

BACKGROUND

Patients with reported β-lactam allergies often receive broad-spectrum antimicrobials and have been shown to experience a variety of negative health consequences, such as increased mortality, costs, readmission, and adverse reactions. Current literature focuses on β-lactam allergy skin testing but lacks evidence on β-lactam allergy interviews (BLAI) when skin testing is unavailable.

OBJECTIVE

This study aimed to test the impact of a pharmacy-led BLAI on duration of fluoroquinolones at a community hospital.

METHODS

A quasi-experimental design with a prospective cohort design and historical control group was used to assess patients with reported penicillin (PCN) allergies in a community hospital. The primary outcome was duration of fluoroquinolones before and after implementation of BLAI. Secondary outcomes included length of stay (LOS), percentage of patients switched to a β-lactam antibiotic, percentage of antimicrobial stewardship recommendations made/accepted, and discrepancies between allergy in medical record and interview-reported allergy. Nonparametric continuous data and medians were evaluated by Mann-Whitney U.

RESULTS

A total of 80 patients were included in the study (43 in the control group and 37 in the prospective group). Fluoroquinolone duration was reduced after the implementation of BLAI (3.7 vs 2.7 days, P = 0.027). In all, 49% of patients in the prospective group were switched to a β-lactam antibiotic after BLAI, with no allergic reactions, adverse effects, or impact on LOS. Conclusion and Relevance: BLAI resulted in a significant reduction in fluoroquinolone duration in patients with PCN allergies and may represent a safe and effective option for institutions lacking skin-testing capabilities.

Pilot Study to Assess Outcomes of a Drug Allergy Clarification Service on a General Medicine Floor at a Local Community Hospital

Purpose

Drug allergy documentation in the patient medical record varies in level of detail, and drug intolerances are often inappropriately documented as an allergy in the medical record. A pilot study was conducted to determine the impact of a pharmacy-led drug allergy clarification service.

Methods

The pilot quality improvement service was implemented in Fall 2016. General medicine patients were identified through daily census reporting and the electronic medical record (EMR) was reviewed within 72 hours of admission for documented drug allergies and/or intolerances. Patients were interviewed by a clinical pharmacist or a fourth year pharmacy student to determine a complete drug allergy and intolerance history.

Results

A total of 55 patients were interviewed and received the pilot service. A drug allergy/intolerance was documented in EMR for 54.5% (n=30) of patients interviewed. Of those 30 patients, 96.6% (n=29) were noted to have at least one discrepancy between EMR documentation and patient interview. The primary discrepancy noted was drug allergies or intolerances documented in the EMR without a description of the reaction.

Conclusion

A pharmacy-led drug allergy clarification service was effective in identifying and clarifying EMR documentation of patients' drug allergies and intolerances. Patients with incorrect or incomplete allergy documentation may receive alternative therapy, which could increase costs and lead to unwanted adverse effects or less effective treatment. As a result of the pilot study, the program has remained in effect and is being expanded to other units within the institution.

Clinical outcomes following inpatient penicillin allergy testing: A systematic review and meta-analysis

BACKGROUND

A documented penicillin allergy is associated with increased morbidity including length of hospital stay and an increased incidence of resistant infections attributed to use of broader-spectrum antibiotics. The aim of the systematic review was to identify whether inpatient penicillin allergy testing affected clinical outcomes during hospitalization.

METHODS

We performed an electronic search of Ovid MEDLINE/PubMed, Embase, Web of Science, Scopus, and the Cochrane Library over the past 20 years. Inpatients having a documented penicillin allergy that underwent penicillin allergy testing were included.

RESULTS

Twenty-four studies met eligibility criteria. Study sample size was between 24 and 252 patients in exclusively inpatient cohorts. Penicillin skin testing (PST) with or without oral amoxicillin challenge was the main intervention described (18 studies). The population-weighted mean for a negative PST was 95.1% [CI 93.8-96.1]. Inpatient penicillin allergy testing led to a change in antibiotic selection that was greater in the intensive care unit (77.97% [CI 72.0-83.1] vs 54.73% [CI 51.2-58.2], P<.01). An increased prescription of penicillin (range 9.9%-49%) and cephalosporin (range 10.7%-48%) antibiotics was reported. Vancomycin and fluoroquinolone use was decreased. Inpatient penicillin allergy testing was associated with decreased healthcare cost in four studies.

CONCLUSIONS

Inpatient penicillin allergy testing is safe and effective in ruling out penicillin allergy. The rate of negative tests is comparable to outpatient and perioperative data. Patients with a documented penicillin allergy who require penicillin should be tested during hospitalization given its benefit for individual patient outcomes and antibiotic stewardship.

Analysis of an Infectious Diseases Pharmacist on Call Pager Program to Inform Educational Efforts

Background: An on call infectious diseases (ID) pharmacist may be used as a resource for physicians, pharmacists, and other health care providers to help answer questions regarding anti-infective agents. Objective: To assess type, requestor, resources dedicated, and temporal trends of questions received through an ID pharmacist on call pager program. A secondary objective was to gather insight as to how this information was utilized to inform educational initiatives. Methods: This was a retrospective study of questions received by the ID pharmacist on call via pager at a large academic medical center. Question data were documented in a central database and analyzed to assess temporal trends and question type, and qualitatively analyzed to determine areas for targeted educational efforts. Results: The ID pharmacist on call recorded 545 questions during the 1-year study period; questions were composed of various antimicrobial agent-related queries, including antibiotic spectrum and selection (n = 251, 46.1%), dosing of antimicrobials (n = 195, 35.8%), and drug monitoring (n = 26, 4.8%). Targeted educational initiatives secondary to questions received included pharmacist education regarding the use of polymyxin antibiotics and antibiotic dosing protocol updates. Conclusions: An ID pharmacist on call pager program was utilized to inquire about antibiotic spectrum and selection for the majority of questions. Records of questions received may be utilized to direct educational efforts and create or revise targeted resources for pharmacists and other clinicians.