Penicillin Allergy Evaluation Research Articles

Opportunities for penicillin allergy evaluation in dental clinics.

To evaluate opportunities for assessing penicillin allergies among patients presenting to dental clinics. Retrospective cross-sectional study. VA dental clinics. Adult patients with a documented penicillin allergy who received an antibiotic from a dentist between January 1, 2015, and December 31, 2018, were included. Chart reviews were completed on random samples of 100 patients who received a noncephalosporin antibiotic and 200 patients who received a cephalosporin. Each allergy was categorized by severity. These categories were used to determine patient eligibility for 3 testing groups based on peer-reviewed algorithms: (1) no testing, (2) skin testing, and (3) oral test-dose challenge. Descriptive and bivariate statistics were used to compare facility and patient demographics first between true penicillin allergy, pseudo penicillin allergy, and missing allergy documentation, and between those who received a cephalosporin and those who did not at the dental visit. Overall, 19% lacked documentation of the nature of allergic reaction, 53% were eligible for skin testing, 27% were eligible for an oral test-dose challenge, and 1% were contraindicated from testing. Male patients and African American patients were less likely to receive a cephalosporin. Most penicillin-allergic patients in the VA receiving an antibiotic from a dentist are eligible for penicillin skin testing or an oral penicillin challenge. Further research is needed to understand the role of dentists and dental clinics in assessing penicillin allergies.

A Synopsis of the Synopses, 2020–2021

A Synopsis of the Synopses, 2020–2021

How We Approach Difficult to Eradicate Helicobacter pylori

How We Approach Difficult to Eradicate Helicobacter pylori

Monitoring allergic reaction to penicillin based on ultrasensitive detection of penicilloyl protein using alkyne response SERS immunosensor

The evaluation of true penicillin allergy is significant to reduce its occurrence and the overdiagnosis before anti-infective treatment. However, the currently available methods with high specificity still face the problem of low sensitivity, thereby easily leading to false negatives. Herein, an alkyne responsive surface-enhanced Raman scattering (SERS) immunosensor is reported for ultrasensitive detection of penicillin allergen penicilloyl protein (P-protein) by using Au-Ag alloy nanoparticles@(antibody + alkyne probe) (as SERS immunoprobe) together with Ag nanofilm modified by antibody (as SERS capture substrate). The SERS immunoassay integrates the interference-free Raman response of high wavenumber region (2212 cm−1) and specific capture antibody with high affinity to selectively recognize P-protein from complicated sample. Meanwhile, the target-induced near-field coupling effect between localized surface plasmon resonances of individual SERS immunoprobe and capture substrate enables the detection of P-protein as low as pg/mL level, and the limit of detection can reach 0.329 pg/mL that is about 6 orders of magnitude lower than the limit defined protein residue (causing penicillin allergy). With the ultrasensitivity and specific selectivity, the proposed SERS immunoassay platform can precisely evaluate the content of P-protein in blood sample or penicillin drugs. It will be a potential tool to monitor allergic reaction to penicillin and better understand the mechanism of penicillin hypersensitivity.

Safety and efficacy of direct two-step penicillin challenges with an inpatient pharmacist-driven allergy evaluation.

Background: Penicillin allergy is commonly reported and has clinical and financial consequences for patients and hospitals. A penicillin evaluation program can safely delabel patients and optimize antibiotic therapy. Pharmacists who perform this task have focused on a detailed interview or penicillin skin testing (PST). Antibiotic graded challenge after PST requires more resources and is more costly than going directly to a two-step challenge. Objective: To determine whether a pharmacist-driven penicillin allergy evaluation and a testing protocol that primarily uses direct oral challenges can safely delabel patients. Methods: Adult patients (ages >18 years) with a penicillin allergy in their electronic medical record (EMR) who were admitted between September 2019 and June 2020 were eligible. Although all patients with penicillin allergy were eligible, priority was given to patients who required antibiotics. Patients were interviewed, and, if indicated, based on an institutional protocol, were tested by using PST and/or two-step oral challenge. If the patient passed the challenge, then the penicillin allergy label was removed in the EMR and the patient counseled. Demographic information, allergy questionnaire results, testing results, and changes in antimicrobial therapy were collected. Results: Fifty patients were evaluated from September 2019 to June 2020. Ninety-six percent of the patients were delabeled, and antibiotic therapy changed for 54%. Twenty patients were delabeled with an interview alone, and 30 patients underwent oral two-step challenge. Only one patient required PST. Conclusion: A pharmacist-driven penicillin allergy evaluation program focused on direct oral graded challenges and bypassing PST can effectively delabel admitted patients. However, more safety data are needed before implementation of similar programs to optimize antibiotic treatment.

Drug Allergy Labels Lost in Translation: From Patient to Charts and Backwards

The current method of defining, reporting, assessment, labeling, delabeling, and reconciliation of adverse drug reactions (ADRs), and specifically immunologically mediated drug hypersensitivity reactions (HSRs), in electronic health records (EHRs) is inadequate and compromises care quality and safety. It is critical to accurately and succinctly report the signs and symptoms associated with ADRs and suspected HSRs to enable clinicians to determine the plausible reaction type and help guide appropriate future management plans. Despite the current limitations of the EHR allergy module, we must encourage improved clinical documentation and demand technological improvements. Telehealth methods have been shown to be valuable in the assessment of ADRs and HSRs, particularly in the case of penicillin allergy evaluation and delabeling. The implementation, assessment, and refinement of advanced technologies, including clinical informatics and artificial intelligence, along with continued education of health care providers have potential to improve EHR documentation and communication, thereby advancing patient safety efforts.

Safety and Outcomes for Penicillin Skin Testing in Pregnancy

Penicillin allergy in pregnant women is associated with increased morbidity and use of less effective antibiotics to treat group B streptococcus infections. Although the American College of Obstetrics and Gynecology recommends evaluation of women with penicillin allergy prior to delivery, testing in pregnancy remains infrequent. We studied the largest known cohort to date of pregnant women who underwent penicillin allergy evaluation to assess the effectiveness and safety of penicillin skin test and oral drug challenge in pregnancy. A retrospective review was conducted of pregnant women with penicillin allergy referred by obstetrics/gynecology to the University of Pennsylvania allergy clinic. We evaluated the index drug reaction, penicillin skin prick and intradermal testing, oral challenge outcomes, and antibiotic use after testing. Eighty-three pregnant women were identified with average gestational age of twenty-six weeks. The culprit drugs included penicillin (33%), amoxicillin (40%), and unknown (36%). Index reaction occurred greater than five years ago in 91% of women. 95% of index reactions were cutaneous or unknown. Skin testing was negative in seventy-six (92%) patients, positive in one (1%) patient, and inadequate or equivocal in six (7%) patients. Eighty women underwent graded challenge to penicillin V or amoxicillin. Seventy-nine tolerated the challenge. One developed isolated itching. Thirty-five patients used intrapartum antibiotics. Penicillin was used in 43% of deliveries. Two patients subsequently had drug reactions. Penicillin allergy evaluation, including drug challenge, can be safely conducted in pregnant women. Similar to the general population, most pregnant women with penicillin allergy have negative testing, and can receive penicillin intrapartum.

Penicillin Allergy Evaluation in Pregnancy Impacts Antibiotic Utilization and Neonatal Clinical Outcomes

Penicillin (PCN) allergy is commonly reported, but many are erroneously labeled. Pregnancy is associated with high antibiotic usage, with indications including prophylaxis for surgical Caesarean section delivery and group B streptococcus (GBS) colonization, a leading cause of neonatal sepsis. PCN allergy evaluation has the potential to significantly impact both maternal and neonatal clinical outcomes, however, proactive drug allergy evaluations during pregnancy remain underutilized.

Identifying and overcoming barriers to inpatient Penicillin allergy de-labeling by non-allergists.

Given the public health burden of a penicillin (PCN) allergy label, non-allergists have been called to evaluate and de-label low risk patients. We discuss barriers identified in implementing a QI initiative aimed to train non-allergists to risk stratify and de-label low risk PCN allergy patients. A PCN allergy risk stratification tool and workflow were created to identify, risk stratify, and de-label low risk patients after oral amoxicillin challenge. The initiative was presented to stakeholders of an adult inpatient unit in a focus group. Participants completed a pre and post survey. Comfort with managing anaphylaxis and priority of PCN allergy de-labeling were assessed via ordinal scale from 0 (none) to 10 (high). Discussion and survey responses identified perceptions and barriers regarding PCN allergy evaluation. 10 participants completed pre and post survey. Barriers to implementing a PCN de-labeling initiative were: lack of provider time, fear of provoking anaphylaxis, poor recognition/management of anaphylaxis, and view of initiative as low priority. Only 50% could identify criteria for anaphylaxis on pre survey (increased to 100% on post), and 60% could identify treatment (increased to 90%). Median pre and post survey comfort level with managing anaphylaxis was 5 and 7 respectively. Median pre & post survey priority of PCN allergy de-labeling was 4.5 and 8 respectively. Successful PCN allergy de-labeling by non-allergists requires identification of clinical champions, ongoing education regarding anaphylaxis, developing sample scripts/dialogue, and reducing time burden by integrating risk tools with decision support guidance and documentation templates into the EMR.

Association of Chronic Diseases with Penicillin Allergy Status– A Retrospective Study

Chronic diseases such as emphysema and heart failure are associated with increased risk of infection and antibiotic use including penicillin; however, the relationship between chronic diseases and penicillin allergy is not well established. Such relationship may serve to guide penicillin allergy evaluation.

162. Assessment of Beta-lactam Allergies as Rationale for Receipt of Vancomycin for Surgical Prophylaxis

BackgroundBeta-lactam (BL) antibiotics are first-line agents for most patients receiving antimicrobial prophylaxis in surgical procedures. Despite evidence showing low cross-reactivity between classes of BLs, patients with allergies commonly receive vancomycin as an alternative to avoid allergic reaction. The objective of this study was to identify potentially inappropriate use of vancomycin surgical prophylaxis among patients with reported BL allergies.MethodsAdult patients (≥18 years) receiving vancomycin for surgical prophylaxis with a reported penicillin and/or cephalosporin allergy at our institution between August 2017 to July 2018 were retrospectively evaluated for potential eligibility for penicillin allergy testing and/or receipt of standard prophylaxis. Surgery type and allergy history were extracted from the electronic medical record. Per our institution’s penicillin-testing protocol, patients with IgE-mediated reactions < 10 years ago were eligible for penicillin skin testing (PST), mild reactions or IgE-mediated reaction > 10 years ago were eligible for direct oral amoxicillin challenge, and severe non-IgE mediated allergies were ineligible for penicillin allergy evaluation or BL prophylaxis.ResultsAmong 830 patients who received vancomycin for surgical prophylaxis, 196 reported BL allergy and were included in the analysis (155 with penicillin allergy alone; 21 with cephalosporin allergy; 20 with both cephalosporin and penicillin allergy). Approximately 40% of surgeries were orthopedic. Six patients were ineligible for BL prophylaxis. Per institutional protocol, 73 of 155 patients (48%) may have qualified for PST; 81 of 155 (52%) patients may have received a direct oral amoxicillin challenge. Only 3 of 22 patients with history of methicillin-resistant Staphylococcus aureus appropriately received additional prophylaxis with vancomycin and a BL.ConclusionPatients with BL allergies often qualify for receipt of a first-line BL antibiotic. An opportunity exists for improved BL allergy assessment as an antimicrobial stewardship intervention. Future studies should evaluate outcomes associated with BL allergy evaluation and delabeling in patients receiving surgical prophylaxis.Disclosures All Authors: No reported disclosures

177. Implementation of Pharmacist-Driven Penicillin Allergy Evaluation and Testing with a Focus on Bypassing Penicillin Skin Testing at an Academic Medical Center

BackgroundPenicillin allergies are reported by approximately 10% of the US population; however, studies reveal that >90% of those patients can tolerate penicillins. Penicillin allergies are associated with negative health outcomes, both clinical and financial, due to reduced efficacy and increased adverse effects of alternative antibiotics. Patient interview, penicillin skin testing (PST) and/or an oral graded challenge can be used to evaluate penicillin allergies. Different facilities use various algorithms for testing. The objective of this project was to determine whether a pharmacist-driven penicillin allergy evaluation and testing protocol which largely bypasses PST could safely de-label patients.MethodsAdult patients (≥18 years) admitted with a penicillin allergy were evaluated for eligibility between September 2019 and June 2020. Pregnant patients, critically-ill patients, and patients receiving test-invalidating medication were excluded. Patients were evaluated and tested using institutional protocols, which allowed for the majority of patients to be challenged without PST. Allergies were removed with standardized documentation, and patients were given a pamphlet and counseled to discourage relabeling. Data collected included but were not limited to, the number of patients challenged and de-labeled, number of patients who were relabeled, and number of patients whose change in allergy status resulted in change of therapy.ResultsForty-eight patients were interviewed and evaluated. One patient was evaluated by PST and oral graded challenge while 27 patients underwent an oral graded challenge only. Twenty patients were de-labeled as a result of patient interview. One patient failed oral challenge with minor itching that did not require any treatment, while 27 patients passed. Forty-seven allergies were removed or modified. Two patients who were de-labeled were relabeled with no record of a new reaction. Of de-labeled patients, 50% received a penicillin following removal of the allergy.ConclusionPenicillin allergies can be evaluated and removed using a pharmacy-driven algorithm that prioritizes direct challenges when appropriate. Risks of a reaction are low, and removal leads to change in treatment in a significant portion of patients.Disclosures All Authors: No reported disclosures

Penicillin Allergy Assessment in Pregnancy: Safety and Impact on Antibiotic Use

Penicillin and other beta-lactam antibiotics are recommended for group B Streptococcus and cesarean section prophylaxis, but approximately 10% of pregnant patients report a penicillin allergy. To assess the safety and impact of penicillin allergy evaluation in pregnant patients. In this retrospective study of obstetrician-ordered Allergy/Immunology (AI) electronic consultations (e-consults) from September 20, 2017 through December 31, 2019, we reviewed the electronic health record for e-consult recommendation; patient demographic, obstetric, and allergyhistories; and peripartum antibiotic utilization withindication. For patients whose electronic consultation recommended an in-person AI evaluation, testing outcomeswere determined, and multivariable logistic regression models were used to compare antibiotic use between patients who did and did not receive an in-person AI evaluation. Of 389 obstetrician-ordered e-consults, 363 (93%) recommended an in-person AI evaluation; of these, 222 (61%) patients received an in-person AI evaluation. Of 220 (99%) patients skin tested, 209 (95%) had their penicillin allergy label safely removed. Compared with patients who did not receive an in-person AI evaluation despite it being recommended (n= 141), patients with in-person AI evaluation (n = 222) had reduced peripartum vancomycin (adjusted odds ratio [aOR], 0.07; 95% CI, 0.01-0.33), clindamycin (aOR, 0.17; 95% CI, 0.08-0.34), and gentamicin (aOR, 0.39; 95% CI, 0.19-0.78) use and increased penicillin (aOR, 18.0; 95% CI, 6.30-51.2) use. Thefully AI evaluated patients had increased first-line antibiotic prophylaxis for group B Streptococcus (aOR, 26.9; 95% CI, 6.32-114) and cesarean section (aOR, 1.94; 95% CI, 1.06-3.52). In a sample of 220 pregnant patients with penicillin allergy histories and in-person AI evaluation, penicillin allergy testing was safe and associated with significantly reduced broad-spectrum antibiotic use and increased first-line beta-lactam antibiotic use.

A055 EXPANDING PENICILLIN ALLERGY EVALUATION FOR PRENATAL PATIENTS

American College of Obstetricians and Gynecologists (ACOG) guidelines recommend penicillin allergy (PA) evaluation for pregnant patients with documented PAs. At our institution, prenatal patients were not receiving PA evaluations.

Diagnostic value and safety of penicillin skin tests in children with immediate penicillin allergy.

Background: The first-line method in the diagnosis of patients who describe an immediate reaction after penicillin intake is a skin test (ST) with penicillin reagents. Objectives: We aimed to determine the safety and diagnostic value of penicillin STs in the diagnosis of immediate reactions to penicillins in pediatric patients. Methods: The study included pediatric patients with suspected immediate reaction to penicillin who were subjected to STs by using a standard penicillin test kit as well as suspected penicillin and the drug provocation tests (DPT) with the suspected penicillin at our clinic. Results: A total of 191 patients (53.9% boys) with a median age of 6.83 years (interquartile range, 4.2-12 years) were included in the study. The time from drug intake to the onset of reaction was ≤1 hour in 138 patients (72.3%) and 1 to 6 hours in 53 patients (27.7%). Penicillin allergy (PA) was confirmed by diagnostic tests in 36 of the 191 patients (18.8%). In multivariate logistic regression analysis, the history of both urticaria and angioedema (odds ratio [OR] 27.683 [95% confidence interval {CI}, 3.143-243.837]; p = 0.003) and anaphylaxis (OR 56.246 [95% CI, 6.598-479.489]; p < 0.001) were the main predictors of a PA diagnosis. Although ST results were positive in 23 patients (63.8%), 13 patients (26.2%) had positive DPT results despite negative ST results. The negative predictive value (NPV) of STs was calculated 92.2% (155/168). None of our patients experienced immediate or delayed systemic and/or local reactions in relation to the STs. Conclusion: A history of urticaria with angioedema and anaphylaxis were the main predictors of true PA in children with suspected immediate reactions. STs with penicillin reagents are safe for use in children. Although STs have a high NPV, DPT is the gold standard for diagnosis. DPTs should be performed as the final step of the diagnostic evaluation of PA in patients with negative ST results.

Penicillin Allergy Delabeling Can Decrease Antibiotic Resistance, Reduce Costs, and Optimize Patient Outcomes.

Antibiotics are one of the most frequently prescribed medications. Among all classes of antibiotics, penicillins are prescribed due to their clinical efficacy, cost-effectiveness, and general safety. Unfortunately, penicillins also are the most common drug allergy listed in patient medical records. Increasing evidence shows that > 90% of patients labeled with a penicillin allergy are not allergic to penicillins and associated β-lactams. The health care consequences of penicillin allergy in the setting of military medicine and readiness are important to consider. In the US, 8 to 10% of the population and up to 15% of hospitalized patients have a documented penicillin allergy, limiting the use of these effective antibiotics. When treating a patient with a penicillin allergy, many clinicians avoid prescribing all β-lactam antibiotics and stay away from cephalosporins due to the concern for potential cross-reactivity. The cost of treating those with a documented penicillin allergy is greater than the cost for those who can receive penicillin, as treatment with broad-spectrum antibiotics often results in longer hospitalizations with increased rates of adverse effects (AEs). Despite preventive programs such as vaccinations, hygiene measures, and prophylactic antibiotics, military personnel are at increased risk for infections due to the military's mobile nature and crowded living situations. Many patients report an allergy to penicillin, but only a small portion have a true immune-mediated allergy. Given the clinical, public health, and economic costs associated with a penicillin allergy label, evaluation and clearance of penicillin allergies improves clinical outcomes, decreases AEs from higher risk alternative broad-spectrum antibiotics, and prevents the spread of antibiotic resistance. In military personnel, penicillin delabeling improves readiness with optimal antibiotic options and avoidance of unnecessary risks, expediting return to full duty.

Preoperative Allergy Testing for Patients Reporting Penicillin and Cephalosporin Allergies is Cost-Effective in Preventing Infection after Total Knee and Hip Arthroplasty

BackgroundRoutine preoperative allergy testing in patients reporting penicillin and cephalosporin allergies increases the number able to receive cefazolin, which should reduce the risk of infection after total knee and hip arthroplasty (TKA/THA), but it remains unclear whether this practice is cost-effective. Using a break-even analysis, we calculated the cost-effectiveness of routine preoperative allergy testing for infection prevention in total joint arthroplasty patients reporting penicillin and cephalosporin allergies. MethodsThe cost of a penicillin allergy evaluation, the cost of revision arthroplasty for prosthetic joint infection (PJI), and baseline rates of PJI in patients receiving a noncefazolin antibiotic in the perioperative period were derived from existing literature. A break-even economic model using these variables was constructed to calculate the absolute risk reduction (ARR) in infection rate needed for preoperative allergy testing to be cost-effective. The number needed to treat (NNT) was calculated from the ARR. ResultsPreoperative allergy testing before TKA and THA in patients reporting penicillin and cephalosporin allergies was cost-effective if the initial infection rate decreased by an ARR of 0.810% (NNT = 123) and 0.655% (NNT = 153) for TKA and THA, respectively. Cost-effectiveness was maintained with varying allergy consultation costs, infection rates, and costs associated with PJI treatment. ConclusionRoutine preoperative allergy testing and clearance are cost-effective infection prevention strategies among patients reporting penicillin and cephalosporin allergies in the setting of elective joint arthroplasty. Widespread adoption of this practice may considerably reduce the economic and societal burden associated with prosthetic infections.

Skin testing and oral amoxicillin challenge in the outpatient allergy and clinical immunology clinic in pregnant women with penicillin allergy

BackgroundPenicillin allergy is frequently reported. In pregnant women, reported penicillin allergy is associated with negative health outcomes and suboptimal group B streptococcal prophylaxis. For individuals having penicillin allergy, skin testing followed by an observed oral challenge is recommended. Previous data indicate a low risk of adverse reaction with skin testing in pregnant women, but the subsequent oral challenge was not routinely pursued. ObjectiveTo determine whether skin testing followed by the outpatient oral challenge is tolerated by pregnant women. MethodsWe conducted a retrospective review of all pregnant women who underwent penicillin allergy evaluation at an outpatient allergy and clinical immunology clinic. The patients underwent oral amoxicillin challenges based on the discretion of the allergy provider. We evaluated the index reaction history, skin test results, oral challenge results, and subsequent antibiotic exposure. ResultsA total of 46 pregnant women underwent skin testing without adverse reactions, of whom 44 patients (95.6%) received negative results. A total of 18 women (39%) completed an oral challenge without adverse reactions. Patients challenged vs not challenged did not differ in patient age, gestational age, latency since index reaction, or reaction history risk level. Notably, 28 women received intrapartum antibiotics. There was no difference in intrapartum antibiotic administration between those who did or who did not complete an in-office oral challenge (P = .90). ConclusionPenicillin skin testing and oral challenge in pregnant women can safely be performed in the outpatient setting. There was no difference in the intrapartum antibiotic use between women who were and those who were not challenged. Further research is needed to determine the utility of oral challenge in pregnant patients.

Inpatient Electronic Consultations (E-consults) in Allergy/Immunology

BackgroundElectronic consultations (e-consults) are asynchronous clinician-to-clinician exchanges within the electronic health record (EHR).ObjectiveWe sought to demonstrate the utility of e-consults in allergy/immunology (A/I) inpatient consultations.MethodsInpatients ≥18 years of age for whom an A/I consultation was requested were eligible for an e-consult. An e-consult was completed if considered appropriate by the A/I physician with recommendations made in the EHR. In-person consultation was performed for inpatients if deemed necessary. Likert scale satisfaction data were collected from requesting providers after the e-consultation. Cost was calculated using time-based billing codes plus the cost of penicillin allergy evaluation, if appropriate.ResultsOf the 109 inpatient consults, 78 (71.6%) were completed through an e-consult and 31 (28.4%) were completed by an in-person consult. The most common indication for an inpatient consult was evaluation of penicillin allergy in 73 (67%) patients. The most common reason to complete an in-person consult was the need to complete penicillin skin testing in 17 of the 31 (55%) patients. E-consults were completed in less time than in-person consults (15 minutes, interquartile range [IQR]: 10-15 vs 60 minutes, IQR: 45-60, P < .001) and had a shorter turnaround time (1 hour, IQR: 0.5-2 vs 7 hours, IQR: 3-19, P < .001). Management recommendations were followed at a similar rate regardless of type of consult (88% of e-consults vs 96% of in-person consults, P = .162). A total of 97% of requesting providers reported an “excellent” or “good” impression of e-consults. E-consults were less costly than in-person consults.ConclusionsE-consults have utility in providing inpatient A/I consultation and may have advantages over in-person evaluation, while adequately maintaining provider satisfaction.

Penicillin Allergy Evaluation Access: A National Survey.

In a study of 121 hospitals from 38 US states, 44% had access to an allergist for inpatient consultations and 39% had access to inpatient penicillin skin testing, indicating that the majority of US hospitals lack sufficient resources to address inpatient penicillin allergies.