Just the facts: penicillin allergy in the emergency department.

As the point of entry into healthcare for many patients, the emergency department (ED) is an ideal setting in which to assess penicillin (PCN) allergies. An estimated 10% of the United States population has a reported PCN allergy; however, few studies have evaluated the prevalence and impact of PCN allergies on antibiotic selection within the ED. Patients with a documented PCN allergy are more likely to be exposed to costly alternative broad-spectrum antibiotics that have higher rates of adverse events, including C. difficile infections. We sought to determine the prevalence of PCN allergies within the UNC Medical Center ED. Key secondary outcomes included the percentage of patients with a documented PCN allergy who (1) received alternative antibiotics (carbapenems, aztreonam, fluoroquinolones, clindamycin, vancomycin), (2) received β-lactam antibiotics and experienced an allergic reaction during their ED visit, and/or (3) had received a β-lactam antibiotic during a past hospitalization or ED visit without their chart being appropriately updated. A retrospective evaluation included patients aged >18 years with a documented PCN allergy who were discharged from the ED between January 1, 2017, and December 31, 2019. Over the study period, there were 14,635 patient encounters with a documented PCN allergy that comprised 8,573 unique patients. The prevalence of PCN allergies was 14.3% for all ED encounters. PCN allergy–labeled patients received alternative antibiotics in 59.4% of ED encounters in which antibiotics were prescribed. Of the 454 β-lactam antibiotics (62 penicillins, 380 cephalosporins, 12 carbapenems) administered to PCN allergy-labeled patients within the ED, there were zero allergic reactions. Also, 18.6% of PCN allergy-labeled patients had received and tolerated a β-lactam antibiotic during prior hospitalizations or ED visits (1.7% penicillins, 14.4% cephalosporins, 2.6% carbapenems) without appropriate updated documentation to reflect β-lactam antibiotic tolerance. These findings confirm the utilization of non–β-lactam antibiotics in PCN allergy-labeled patients, highlighting the importance of accurate and updated allergy documentation in the electronic medical record. These findings also demonstrate the need for improved allergy documentation and protocols to proactively assess penicillin allergy labels while in the ED.Funding: NoDisclosures: None

Penicillin (PCN) allergy is one of the most frequently reported medication allergies, with ~10% of the US population reporting a PCN allergy. However, studies have shown that only 1% of the US population have a true IgE-mediated reaction to PCN. Delabeling and appropriately updating patient allergy profiles could decrease the use of alternative broad-spectrum antibiotics, rates of infectious complications [C. difficile, methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococcus (VRE)], antibiotic resistance, and overall healthcare cost. The emergency department (ED) is an important setting in which to assess PCN allergies and to delabel patients when appropriate because there are >130 million ED visits in the United States each year. We sought to determine the percentage of PCN allergy–labeled patients who could be delabeled through a PCN allergy assessment interview in an ED. Key secondary outcomes included the percentage of interviewed patients who could not be delabeled based on history alone but would be eligible for an amoxicillin oral challenge or a PCN skin test (PST). A prospective PCN allergy assessment pilot was performed for patients aged >18 years presenting to the UNC Medical Center ED between December 1 and December 17, 2020, with a documented PCN allergy. A pharmacist conducted penicillin allergy assessments on a convenience sample of patients presenting to the ED between 8 a.m. and 3 p.m. on weekdays. Based on patients’ reported and documented histories, charts were updated with the most accurate information and allergies were delabeled if appropriate. In total, 95 patients were assessed; 62 (65.3%) were interviewed and 15 (24.2%) were delabeled. In addition, 26 patients (41.9%) were deemed eligible for an oral amoxicillin challenge, 19 (30.6%) qualified for a PST, and 2 (3.2%) patients did not qualify for further assessment due to having a an IgE-mediated reaction in the past 5 years. Of the 15 patients who were delabeled, 6 (40.0%) received antibiotics during their admission: 4 (73.3%) of those patients received a penicillin and 2 (36.7%) received a cephalosporin, all without adverse reactions. Patient assessments took ~20 minutes to complete, including chart review, patient interview, and postinterview chart updating. The results from this pilot study demonstrate the impact of performing PCN allergy assessments in ED. Interdisciplinary opportunities should be explored to develop processes that will improve the efficiency and sustainability of PCN allergy assessments within the ED to allow this important stewardship intervention to continue.Funding: NoDisclosures: None

BackgroundWhile penicillin (PCN) allergies are commonly reported, their cross-reactivity with beta-lactam antibiotics is minimal. First line treatment of gonorrheal infections includes a cephalosporin (CPH). In an emergency department (ED) environment, physicians must consider potential allergies when selecting antibiotics for a patient with symptoms concerning for sexually transmitted infection (STI).MethodsA retrospective chart review on adult patients with symptoms concerning for STI presenting to an urban ED from January 2014 through June 2019 was performed. Chart discovery was performed using search terms of “STI”, “STD”, “urethritis”, “vaginitis”, and “gonorrhea”. Information abstracted included patient symptoms, type of care provider, and antibiotics prescribed or administered in the ED. The primary outcome was prevalence of allergy to PCN and CPH in patients evaluated for STI symptoms and secondary outcomes included prescribed antibiotic treatments. Chi-square and Fischer-exact tests were utilized to examine for statistical significance, with p values < 0.05 as statistically significant.ResultsA total of 603 patients met the inclusion criteria, of which 31 reported allergies to PCN, and another 3 reported allergies to CPH. Patients reporting PCN allergy were found to be less likely to receive a CPH antibiotic (p=0.0035). Patients reporting a non-anaphylactic allergy to PCN received a CPH at a rate of 92.3%. Attending physicians in particular were less likely to prescribe a CPH antibiotic to a patient reporting allergy compared with both resident physicians and PAs (p=0.00019). Patients reporting a PCN allergy were more likely to receive alternative antibiotics beyond CPH or azithromycin (p=0.046); the most frequently given antibiotics were metronidazole, doxycycline, and levofloxacin.Demographic DataAntibiotic Prescriptions by Type of Penicillin AllergyAntibiotic Prescriptions for Penicillin Allergy vs. No AllergyConclusionPatients with PCN allergies represent a recurring challenge for ED physicians when faced with antibiotic selection for STI symptoms concerning for gonorrheal infection. Those with PCN allergies are significantly less likely to receive a CPH antibiotic, though these remain the only universal treatment for gonorrheal infections. These findings highlight the significant need for further physician education on allergies and antibiotic selection.DisclosuresAll Authors: No reported disclosures

BackgroundPenicillin allergy is the commonest reported drug allergy in the UK. However, it is estimated that under 10% are true allergies. Evidence shows that using second-line antibiotics is associated with worse clinical outcomes, greater healthcare costs and increased risk of antimicrobial resistance.ObjectivesTo evaluate the completeness of allergy history taking as per Trust guidelines on penicillin allergy classification, for patients with a positive penicillin allergy status presenting through the Emergency Department (ED) at the Royal Berkshire Hospital (RBH).MethodsIn the first audit, 30 consecutive patients prescribed antibiotics in the acute medical unit (AMU) via ED at RBH were selected in April 2021. Electronic patient records were reviewed for the percentage documentation of the causative antibiotic, symptoms, time and management of reaction in those with an active penicillin allergy status. Findings were fed back to the ED team at departmental teaching. Thirty consecutive patients with recorded penicillin allergy presenting to ED were selected for re-audit in June 2021.ResultsA small improvement in penicillin allergy history documentation was seen between the first audit and re-audit (Figure 1). However, 56% of patients' notes still lacked enough information to classify severity. Under 5% of patients' documented allergy history constituted absolute contraindication to penicillin-based antibiotics (Figure 2).Figure 1.A bar chart comparing the completeness of penicillin allergy history documentation between audits 1 and 2.Figure 2.A pie chart summarizing the severity categorization by documented history in all audited patients with a recorded penicillin allergy.ConclusionsPenicillin allergy documentation in patients presenting through ED at RBH remained below the standard of Trust guidance despite educating the ED team on the issue. This project has instigated an update in the Trust penicillin allergy classification guidelines and a multidisciplinary quality improvement project to identify and challenge inappropriate penicillin allergy labels.

BackgroundThe Surviving Sepsis Campaign Guidelines recommends administration of broad-spectrum antibiotics within 1 hour of sepsis diagnosis; electronic order sets drive antibiotic selection with pre-populated regimens based on the suspected infectious indication. Given the low rate of cephalosporin cross-reactivity in patients with a PCN allergy, we modified our ED sepsis order set (Images 1 and 2) to include cephalosporin options in patients with reported mild-to-moderate PCN reaction histories. This was a single-center, retrospective analysis evaluating the impact of this change on antibiotic prescribing and associated outcomes.MethodsAn electronic medical record (EMR) report identified patients ≥18 years of age with a documented PCN allergy that received antibiotics via the ED sepsis order set from December 30, 2012 to September 28, 2013 (pre-intervention) and January 3, 2014 to July 18, 2015 (post-intervention). The primary objective was to compare antibiotic days of therapy (DOT) and length of therapy (LOT) between the pre- and post-groups. The secondary objectives included 30-day readmission and mortality, hospital length of stay (LOS), incidence of C. difficile within 6 months and documented hypersensitivity reactions. Bivariate analyses, with chi-square, Mann–Whitney U, and Poisson means test, were used.ResultsA total of 180 patients (90 pre- and 90 post-intervention) were included. Demographics were similar between groups, with the exception of congestive heart failure (CHF) which was more prevalent in the post-intervention group (P = 0.039). Aztreonam, vancomycin, aminoglycoside, and fluoroquinolone DOTs were significantly reduced (P < 0.001) while cephalosporin DOTs significantly increased (P < 0.001) in the post-intervention group. There were no statistical differences in antibiotic LOT, 30-day readmission and mortality, hospital LOS, or incidence of C. difficile infection. For those patients that received cephalosporin antibiotics, there were no hypersensitivity reactions documented in the EMR.ConclusionStratifying ED sepsis order sets by PCN allergy history severity is a safe and effective intervention that reduces second-line antibiotics in PCN allergic patients presenting to the ED with suspected sepsis.DisclosuresAll authors: No reported disclosures.

The Use of Penicillin Skin Testing to Assess the Prevalence of Penicillin Allergy in an Emergency Department Setting

PEN-FAST-ED: Utilizing the PEN-FAST decision tool to guide antibiotic prescribing in the emergency department.

Penicillin allergy is the most common drug allergy reported. About 8-10% of individuals in the USA have a documented penicillin allergy, yet 90% are not truly allergic to penicillin. A penicillin allergy "label" results in increased antibiotic-related adverse reactions and increased health care costs, thus impacting the overall "readiness" of the military. A review of the current literature and approaches to penicillin allergy and "de-labeling" a patient who reports penicillin allergy was conducted and future strategies to identify and assess military beneficiaries were outlined. Military allergists had a formal discussion at the Tri-service Military Allergy Immunology Assembly regarding the state of penicillin allergy testing in military allergy clinics. A PubMed search yielded 5,775 results for "penicillin allergy" and 484 results for "penicillin allergy testing." There were two formalized penicillin testing programs in the military treatment facilities. In 2017, the military trained nearly 165,000 new recruits. If 5-10% reported a penicillin allergy and 90% were de-labeled, that would yield a $15-30 million cost savings annually. Further, de-labeling of the 9.4 million active duty, beneficiaries and retirees with a 90% success rate could result in even greater savings for the military health care system. A penicillin allergy label is a risk to military readiness secondary to associated increases in the length of hospitalizations and emergency department and medical visits. Penicillin de-labeling is a simple intervention that can improve readiness, significantly decrease health care costs and prevent antibiotic resistance, as well as antibiotic-associated adverse events. The military allergist should be "front and center" providing expertise guidance and leadership for clinic and hospital-based penicillin de-labeling efforts which are nested within the antibiotic stewardship programs.

Penicillin allergy is commonly reported in the pediatric emergency department (ED). True penicillin allergy is rare, yet the diagnosis results from the denial of first-line antibiotics. We hypothesize that all children presenting to the pediatric ED with symptoms deemed to be low-risk for immunoglobulin E-mediated hypersensitivity will return negative results for true penicillin allergy. Parents of children aged 4 to 18 years old presenting to the pediatric ED with a history of parent-reported penicillin allergy completed an allergy questionnaire. A prespecified 100 children categorized as low-risk on the basis of reported symptoms completed penicillin allergy testing by using a standard 3-tier testing process. The percent of children with negative allergy testing results was calculated with a 95% confidence interval. Five hundred ninety-seven parents completed the questionnaire describing their child's reported allergy symptoms. Three hundred two (51%) children had low-risk symptoms and were eligible for testing. Of those, 100 children were tested for penicillin allergy. The median (interquartile range) age at testing was 9 years (5-12). The median (interquartile range) age at allergy diagnosis was 1 year (9 months-3 years). Rash (97 [97%]) and itching (63 [63%]) were the most commonly reported allergy symptoms. Overall, 100 children (100%; 95% confidence interval 96.4%-100%) were found to have negative results for penicillin allergy and had their labeled penicillin allergy removed from their medical record. All children categorized as low-risk by our penicillin allergy questionnaire were found to have negative results for true penicillin allergy. The utilization of this questionnaire in the pediatric ED may facilitate increased use of first-line penicillin antibiotics.

BackgroundMany children present to emergency departments (EDs) with a reported allergy to penicillin.1 There is growing data to support key historical features to accurately stratify patients into low and high-risk...

Commentary

Background Up to 10% of children are labelled as penicillin allergic, requiring the use of suboptimal antibiotics as an alternative. In these children, a low-risk oral challenge with amoxicillin can be done to evaluate the accuracy of this allergy. An oral challenge pre-written order was implemented in our institution’s emergency department (ED). Objectives The aim of this study was to assess the success of the amoxicillin oral challenges in children labelled penicillin allergic in the ED. Design/Methods This is an ongoing prospective observational study conducted at a tertiary care paediatric hospital. Children considered at low risk of penicillin allergy (https://www.inesss.qc.ca/fileadmin/doc/INESSS/Rapports/Medicaments/Outil_aide-decision_allergies-EN_VF.pdf) and requiring amoxicillin according to the ED physician were prescribed an amoxicillin challenge according to a pre-written order set. In the absence of a reaction, patients were discharged with an amoxicillin prescription. Parents were contacted one month after the challenge to assess for late-onset reactions. Results Since June 2021, 70 children (24 female) underwent an amoxicillin challenge in the ED (Figure 1). The patients’ median age was 1 yo (6 months–12 yo). The most frequent discharge diagnoses in the ED were otitis media (65%) and pneumonia (24%). The challenge was successful in the ED for 69/70 (99%) patients. Sixty-two (89%) patients were successfully contacted for a follow-up phone call. Among them, 55/62 (89%) did not present any reaction. In total, 7/62 (11%) of the children had a reported reaction, one (1%) child had an immediate reaction to the challenge in the ED, while 6/62 (10%) had a rash appearing 1 to 61 days after the first dose of antibiotics. No severe reactions were reported by the parents after discharge from the ED. A correlation between the amoxicillin administration and the delayed reaction was considered less likely for 3/6 patients because of the later onset of symptoms (28-61 days). The three other patients were considered not to have a penicillin allergy after formal assessment at the allergy clinic. Conclusion Using a standardized pre-written order set for an amoxicillin challenge in the ED allowed 99% of participating children to be discharged safely with an amoxicillin prescription. Despite 10% presenting a rash after discharge, none were considered to have a late-onset reaction. This removed safely and rapidly the label of “penicillin allergy” from those paediatric ED patients, allowing optimal first-line antibiotics. It also eliminates the need for a consultation with an allergist in the majority of patients.

Impact of Penicillin Allergy on Time to First Dose of Antimicrobial Therapy and Clinical Outcomes

Background Although penicillin allergy is commonly reported, less than 1% of the population are truly allergic to penicillin. False penicillin allergy labelling may be associated with suboptimal antibiotic selection, greater costs, and higher prevalence of antibiotic-resistant organisms. The purpose of this study was to evaluate outcomes of implementing a pharmacist-led penicillin-allergy screening protocol on the antibiotic prescribing habits and the appropriateness of selecting first line antimicrobial therapy. Methods A retrospective, quasi-experimental study included 97 patients with suspected or confirmed common infections. Data was collected between January 2020 to August 2021 for the pre-protocol implementation group (PPG) and between November 2021 to April 2022 for the post-protocol implementation group (PPI). Adults ( &amp;gt; 18 years) with a documented penicillin allergy were included. Patients with penicillin allergy were identified and interviewed by our Emergency Department (ED) clinical pharmacists using an evidence-based algorithm. Data were analyzed using two-sample Student’s t-test and descriptive statistics. Results Fifty-one patients in PPG and 46 in PPI. In the PPG, 60.8% (31/51) had a history of beta-lactam tolerance and 26% (8/31) tolerated at least a penicillin derivative previously. While, twenty-two patients (47.8%) in the PPI tolerated beta-lactams and 50% (11/22) tolerated at least one penicillin derivative. Thirty-eight patients (82.6%) had a documented infection in the PPI and received an antibiotic. The use of Moxifloxacin was significantly lower in the PPI vs the PPG, 0% (0/38) vs 17.6 (9/51) respectively, (P=0.008). However, the use of ciprofloxacin, vancomycin, and aztreonam was lower in the PPI vs the PPG but was not statistically significant (Table 2). Antibiotic therapy appropriateness was higher in the PPI as compared to the PPG, 86.8% (33/38) vs 49% (25/51) respectively, (P=0.0004). In the PPI, documented penicillin allergies were delabeled in 23.9% (11/46) of patients. Conclusion We observed higher rates of appropriate first line antibiotic therapy selection post-implementation of the pharmacist led penicillin allergy screening protocol. This could be an effective strategy to optimize antimicrobial therapy in the hospital setting. Disclosures All Authors: No reported disclosures.

Barriers to penicillin allergy delabeling in a pediatric emergency department