Documented Beta-lactam Allergy Research Articles

1837. Evaluation of Disparities in Beta-Lactam Allergies and Subsequent Antibiotic Use in Outpatients with Acute Bacterial Skin and Skin Structure Infections

Abstract Background Black patients with skin and soft tissue infections are more likely to have a documented penicillin allergy and use of non-beta-lactams than white patients. We sought to compare the prevalence and risk factors for documented beta-lactam allergy (D-BLA) among racial and ethnic minorities (REM) and white patients and beta-lactam (BL) use for outpatient Acute Bacterial Skin and Skin Structure Infections (ABSSSIs). Methods We conducted a cohort study of adult outpatients (18-90 years) seen by the Texas Tech University Health Science Center Physicians group (2012-2021). All patients had an ICD-9 or ICD-10 code for an ABSSSI in the primary or secondary position. Descriptive statistics were reported. Logistic regression models were used to determine which factors were statistically associated with D-BLA and which factors were associated with BL use for the ABSSSI. Multivariable (MV) analysis results were reported as odds ratios (OR) and 95% confidence intervals (95%CI). All analyses were conducted in R. Results REM represented 38% of the 21,673 patients in the cohort. A D-BLA was present for 18% percent of all patients and was higher in white patients than REM (22 vs 13%). Factors associated with D-BLA on MV analysis of the total cohort were age (OR 1.01 per year, 95%CI 1.01-1.01), Medicaid (OR 1.18, 95%CI 1.04-1.34), or Medicare (OR 1.17, 95%CI 1.05-1.31). Factors associated with a lower likelihood of D-BLA on MV analysis of the entire cohort were REM (OR 0.55, 95%CI 0.51-0.60) and male sex (OR 0.56, 95%CI 0.52-0.60). Regarding BL use, white patients were less likely to receive a BL than REM (26 vs 30%). Factors associated with a reduced likelihood of BL use on MV analysis of the total cohort were D-BLA (OR 0.60, 95%CI, 0.54-0.67), Medicaid (OR 0.83, 95%CI 0.74-0.93), or Medicare (OR 0.64, 95%CI 0.58-0.70). Factors associated with BL use on MV analysis of the entire cohort were REM (OR 1.20, 95%CI 1.12-1.28), male sex (OR 1.45, 95%CI 1.36-1.54), or self-pay (OR 1.52, 95%CI 1.37-1.68). The interaction term between REM and D-BLA was not significant for BL use. Conclusion REM were at a reduced risk of a D-BLA in our cohort and were more likely to receive a BL for ABSSSIs. Payor status and sex also significantly impacted rates of D-BLA and BL use. Disclosures Ronald G. Hall, II, PharmD, MSCS, Merck: Grant/Research Support Carlos Alvarez, PharmD, MSc, MSCS, Boehringer Ingelheim: Grant/Research Support|Bristol Myer Squibb: Grant/Research Support|Merck: Grant/Research Support

Impact of a Pharmacist-Conducted Preoperative Beta-Lactam Allergy Assessment on Perioperative Cefazolin Prescribing

Background: Cefazolin is guideline recommended for perioperative prophylaxis in orthopedic surgery. Despite its unique R1 side chain, cefazolin is often avoided in patients with beta-lactam allergy with concern for cross reactivity. Objectives: The primary outcome was the percentage of patients who received cefazolin perioperatively. Secondary outcomes included the percentage of patients with a beta-lactam allergy clarified following the telephone interview and clinical outcomes including acute kidney injury, surgical site infection, Clostridioides difficile infection, and re-admission at 30 and 90 days. Methods: This single-center, quasi-experimental study evaluated a pilot program in which a pharmacist phoned patients > 18 years of age with a scheduled orthopedic surgery and a documented beta-lactam allergy to assess their allergy preoperatively. Recommendations to use cefazolin were based on an algorithm. Patients were divided into pre- and post-intervention cohorts. Results: A total of 832 patients were screened for inclusion with 135 and 66 patients included in the pre- and post-intervention cohorts. No significant difference was identified in the primary outcome. In the post-intervention cohort, 62% had a beta-lactam reaction updated in the electronic medical record. Those with a beta-lactam allergy delabeled or made less severe were numerically more likely to receive cefazolin than those with an unchanged reaction or a reaction made more severe (95.2% vs 68% vs 65%). There were no differences in clinical outcomes between groups. Conclusion: A pharmacist-conducted preoperative beta-lactam allergy interview in adult patients undergoing elective orthopedic surgery improved beta-lactam allergy documentation but, did not result in increased utilization of cefazolin.

562. Multipronged Approach to Recruitment of Pediatric Patients with Beta-Lactam Allergies for Evaluation and De-labeling

Abstract Background Penicillin allergy is the most commonly reported drug allergy in the pediatric population. However, most reports do not represent true IgE-mediated or late-onset severe hypersensitivity reactions. False allergy labels can lead to unnecessarily broad and/or non-first line antibiotic utilization, the development of antibiotic resistance, adverse drug side effects, and have implications for the use of antimicrobials in adulthood. In an effort to decrease inappropriate allergy labeling, we have implemented a multipronged approach for the evaluation of documented beta-lactam allergies in pediatric patients and potential “de-labeling” of inaccurate or outdated allergies. Methods We performed retrospective chart review of pediatric patients (0-18 years) with a documented beta-lactam allergy who were seen in clinic at a single tertiary medical center between 2014-2019. Prospective telephone screening then began to further characterize reaction symptoms and timing to determine patient candidacy for allergy testing (Fig. 1). Inpatient screening began in April 2022. If amenable to referral, eligible patients are then referred for outpatient Allergy and Immunology (A/I) assessment. Figure 1Process map for pediatric beta-lactam allergy risk-stratifying algorithm. Results A total of 1160 eligible pediatric patients were identified, and initial results are summarized (Fig. 2). Of those screened, 48 (57%) patients were referred. 5 (6%) patients were de-labeled via screening, of which 3 had received and tolerated repeat dosing. 11 (33%) patients have attended allergy appointments; 4 (36%) were tested and all were de-labeled (ages 6-11 years) from mostly non-IgE-mediated reactions. Additionally, 16 patients have upcoming appointments, and recruitment efforts are ongoing to include increased inpatient recruitment. Conclusion Use of an inpatient and outpatient algorithm can help identify pediatric patients less likely to have a true or persistent beta-lactam allergy (delayed-onset mild symptoms, or IgE-mediated reaction >5 years ago) and who could benefit from formal allergy testing to potentially remove their allergy label. In the future, algorithm implementation within the electronic medical record may assist clinicians in thorough documentation of beta-lactam allergies and expeditious referral for allergy testing when appropriate. Disclosures All Authors: No reported disclosures.

1745. Drilling Down on Antibiotic Use in Dental Clinics

Abstract Background Dentists are the third highest prescribers of antibiotics in outpatient settings in the US with reported suboptimal prescribing rates between 30 and 85%. The 2019 American Dental Association guidelines provide guidance for antibiotic use based on the presence of dental pain and/or swelling and whether definitive conservative dental treatment is immediately available. Our primary objective was to assess the appropriateness of systemic antibiotic use in our institution’s dental clinics based on these guidelines. Our secondary objectives were to describe antibiotic choice, duration of therapy, and use of non-first line antibiotics. Methods From January 2021 through December 2021 data on antibiotics prescribed during all patient encounters in our institution’s dental clinics were abstracted from the electronic medical record. Detailed review was performed on a randomly generated sample of 120 unique patient encounters (10 each month). First line antibiotics included penicillin, amoxicillin, and amoxicillin-clavulanate. Results Of 14,381 dental clinic encounters, 2,413 (16%) resulted in one or more antibiotic prescriptions (total of 2788 prescriptions). Non-first line antibiotics accounted for 402 (14%) of all antibiotic prescriptions (Table). Sixty-nine (17%) of non-first line antibiotics were prescribed for patients with no documented beta-lactam allergy. Of the 333 non-first line antibiotics prescribed for patients with a documented beta-lactam “allergy”, a first line antibiotic or cephalexin could have been used in 120 (36%). Of 120 patient encounters undergoing detailed review, antibiotics were prescribed for treatment (not prophylaxis) in 115 (96%). Antibiotics were indicated in only 16 of 108 (14%) evaluable patients. The mean duration of therapy was 7.2 days. Eleven percent of prescriptions were longer than 7 days. Conclusion At our institution most antibiotics prescribed from our dental clinics were for treatment, were commonly not indicated, and were usually prescribed for 7 days or more. First line antibiotics and cephalexin could have replaced nearly half of the non-first line antibiotics prescribed. Developing a clinical pathway incorporating updated guidelines and management of patients with beta-lactam “allergies” may improve patient care. Disclosures All Authors: No reported disclosures.

891. Challenging the Dogma of Beta-Lactam Allergies: Impact of an Antimicrobial Stewardship Program

Abstract Background Penicillin allergies are reported in approximately 10% of patients in the US but ∼90% of these allergies can be de-labeled. Consequences of inappropriate allergy labeling leads to use of alternative agents associated with increased adverse events and resistance rates, leading to worse outcomes. Though all beta-lactam agents share the core beta-lactam ring, the R1 side chain has been identified as the focus of cross-reactivity. Agents that do not share the same or similar R1 side chain are likely to have negligible risk of hypersensitivity reactions. The purpose of this study was to assess the incidence of hypersensitivity reactions in patients with a documented beta-lactam allergy that received a beta-lactam agent with a different side chain based on recommendation by an antimicrobial stewardship clinical pharmacist. Methods This was a retrospective, single-center, observational study of patients admitted to NYU Langone Hospital – Long Island from October 2019 to February 2022. Data was collected by review of the electronic medical record and descriptive statistics were generated as appropriate. The primary outcome was the proportion of patients that experienced a hypersensitivity reaction to a beta-lactam agent with a different side chain. Secondary outcomes included impact of antimicrobial stewardship intervention by clinical pharmacists, avoidance of alternative antibiotics, and cost comparison between agents requested and recommended. Results A total of 181 patients were included in the final analysis, including 37 patients with a history of anaphylaxis. No patients with a documented beta-lactam allergy experienced a hypersensitivity reaction upon receiving a beta-lactam agent with a different side chain. Within the cost comparison, meropenem accounted for 45.6% and 75.9% of the total minimum and maximum wholesale costs of requested agents, respectively. Conclusion The results of this study suggest that receipt of a beta-lactam agent with a different side chain is safe in patients with a history of beta-lactam allergy, including anaphylaxis history, and supports 'in the moment' antimicrobial stewardship intervention to ensure patients receive optimal therapy when access to in-depth allergy history or detailed patient interview is not feasible. Disclosures All Authors: No reported disclosures.

1805. Safety Outcomes Following Beta-Lactam use in Patients with a Documented Beta-Lactam Allergy

Abstract Background Management of bacterial infections typically consist of beta-lactam antibiotics. Individuals with histories of beta-lactam allergy are more likely to receive alternative broad-spectrum antibiotics which may be less efficacious or lead to increased adverse events. Patients can be prescribed full doses of structurally non-related beta-lactam antibiotics due to the low similarity of side chains between these medications and penicillin, and the low incidence of penicillin allergies being true allergies. Nevertheless, there is a lack of data regarding safety outcomes in patients who are treated with a beta lactam with a documented allergy. Methods This was a single-center retrospective observational study of patients with a documented beta-lactam allergy who received at least one dose of any beta-lactam antimicrobial excluding aztreonam from SUNY Downstate Health Sciences University between January 2015 – October 2021. Electronic medical records were reviewed for relevant study data. The primary outcome was the incidence of allergic reaction on full dose beta lactam with a documented allergy in the medical record. Results Baseline characteristics are summarized in Table 1. Two patients experienced a suspected allergic reaction while on beta-lactam therapy. Anaphylaxis was not reported and pharmacologic rescue agents were not required for each case. The antimicrobial agent was changed after the reaction was noted in both cases. Conclusion Patients who were administered beta-lactam antimicrobials with beta-lactam allergy had low rates of allergic reaction. The rate of allergic reactions observed is similar to the incidence of allergy in patients without documented allergies reported in the literature. Administration of beta-lactams with dissimilar side chains such as beta-lactam beta-lactamase inhibitors and third and fourth generation cephalosporins were safely administered to patients with a documented allergy. Disclosures All Authors: No reported disclosures.

107. Impact of Penicillin Allergy Assessment During Pre-Anesthesia Testing (PAT) on Beta-Lactam Surgical Prophylaxis in Bariatric Surgery Patients

BackgroundDue to utilization of alternative antibiotics, documented penicillin (PCN) allergies are associated with an increased risk of surgical site infections, cost, and infections caused by resistant organisms. In October 2019, a community hospital implemented a beta-lactam (BL) allergy assessment service in a pre-anesthesia testing (PAT) clinic without access to allergy specialists or PCN skin testing (PST). In phase 1, the surgeon was contacted to change surgical prophylaxis for BL eligible patients based on the assessment. In phase 2, an automatic protocol was implemented to allow advanced practice providers (APPs) to switch from alternative antibiotics in BL eligible patients. The objective of this study was to assess the impact of the PCN assessment service and protocol on BL surgical prophylaxis.MethodsThis retrospective cohort study included bariatric surgery patients who visited PAT clinic with a documented BL allergy between Jun 2019-Sept 2019 (control), Nov 2019-Feb 2020 (phase 1), and Nov 2020-Feb 2021 (phase 2). Patients with procedures not requiring surgical prophylaxis were excluded. Patients were determined to be eligible for BL surgical prophylaxis if: intolerance or mild-moderate reaction to PCN, previously tolerated cephalosporin, intolerance to cephalosporin, or surgeon deemed it appropriate. The primary outcome was overall utilization of BL surgical prophylaxis. ResultsThis study included 38 patients in the control group, 14 in the phase 1 group, and 17 in the phase 2 group. Overall utilization of BL surgical prophylaxis significantly increased with 16% in the control group, 43% in the phase 1 group, and 65% in the phase 2 group (p=0.001). In the BL eligible patient subgroup, BL surgical prophylaxis significantly increased with 35% (n=6/17) in the control group, 50% (n=6/12) in the phase 1 group, and 92% (n=11/12) in the phase 2 group (p= 0.001). There were no reported surgical site infections or adverse drug reactions. ConclusionOverall utilization of BL surgical prophylaxis significantly increased after implementation of a PCN allergy assessment service with an automatic protocol for patients determined as BL eligible. This service and protocol demonstrates successful optimization of surgical prophylaxis when allergy specialists or PST is not available.Disclosures All Authors: No reported disclosures

Non-irritating skin test concentrations for ceftazidime and aztreonam in patients with a documented beta-lactam allergy

Non-irritating skin test concentrations for ceftazidime and aztreonam in patients with a documented beta-lactam allergy

Impact of Beta-Lactam Allergies on Selection of Antimicrobials in an Inpatient Setting Among Veteran Population.

Beta-lactam antibiotics are among the most common and widely used antibiotics. However, reported allergy to this class of antibiotics is also common, leading to the use of alternative broad-spectrum antibiotics by healthcare providers. This has led to the emergence of various negative health outcomes. The purpose of the study is to investigate the impact of using alternative antibiotics secondary to a beta-lactam allergy among U.S. veterans who have otherwise multiple comorbidities. This retrospective observational analysis was conducted over a 5-year period (January 1, 2011 to December 31, 2016) at the Memphis Veterans Affairs Medical Center (VAMC). Admitted patients with a documented beta-lactam allergy were categorized to preferred or non-preferred status based on initial antibiotic therapy antibiotic, allergy history, published guidelines, and local antibiogram. Preferred therapy was defined as the optimal antibiotic treatment for a given indication based on patient allergy history, published Infectious Disease Society of America guidelines, and local antibiogram of Memphis VAMC. The therapy was classified as "non-preferred" if it did not satisfy the preferred therapy criteria. Non-preferred treatments were further assessed for appropriateness based on indication and patient-specific factors. Chi-square and Fisher's exact tests were conducted to find a difference in rates of negative sequelae among patients receiving preferred vs. non-preferred treatments and appropriate vs. inappropriate treatments. Of the 1806 admissions identified, data were collected on 95 unique patients with 147 different antibiotic regimens. There were 68 (52%) preferred treatment regimens and 64 (48%) non-preferred treatment regimens. Of the 64 non-preferred treatments, 43 (67%) were inappropriate. There was a statistically significant decrease in the number of adverse drug events and in the combined negative sequelae outcome among patients receiving preferred therapy vs. non-preferred therapy (2 vs. 12; P < .01 and 11 vs. 23; P < .01, respectively). The receipt of non-preferred antibiotic therapy among veterans with a recorded beta-lactam allergy may be associated with an increased risk of developing negative outcomes. Among military personnel, removing unnecessary beta-lactam allergies would improve readiness with optimal antibiotic choices and avoidance of unnecessary risks, expediting return to full duty.

906. Surgical Site Infections in Children with Beta-Lactam Allergy: A Matched Cohort Study

BackgroundSurgical site infections (SSIs) are a significant cause of morbidity and mortality. The administration of appropriate pre-operative antimicrobial prophylaxis (AMP) reduces SSI risk and beta-lactam antibiotics are considered the most effective agents. Studies in adult patients found increased SSI risk in patients with documented beta-lactam allergy (BLA) due to use of second line AMP agents. The SSI risk in BLA pediatric patients is not well-described.MethodsWe conducted a retrospective matched cohort study of patients (1-19 years-old) who underwent a surgical procedure at a quaternary pediatric hospital during 2010-2017. Patients with documented BLA at the time of surgery were matched 1:1 to patients with no BLA by age at surgery, National Surgical Quality Improvement Program (NSQIP) category, surgical calendar year, and presence of complex chronic conditions (CCC). AMP by BLA status was considered appropriate if recommended by the 2013 American Society of Health-System Pharmacists (ASHP) guidelines, antibiotic class appropriate, or recommended by an infectious disease physician. McNemar’s test was used to assess differences in SSI rates and antibiotic regimen appropriate for BLA status between BLA and no BLA groups.ResultsOf the 11878 surgical procedures among 9781 patients during the study period, 1021(9%) of patients had a reported BLA and we matched 972. SSI was rare in both groups and there was no significant difference in rates (18 (1.9%) in no BLA, 17 (1.8%) in BLA, p=1.0). BLA were more likely to receive an antibiotic regimen considered inappropriate for BLA status (22%) compared to no BLA (3%) with 89% receiving a beta-lactam-containing AMP regimen (p< 0.01).ConclusionBLA was not associated with increased SSI risk in the pediatric patients studied. Interestingly, a significant proportion of children with a documented allergy received a beta-lactam for AMP. This suggests some providers recognize that allergy labels are inaccurate and may be comfortable administering beta-lactam AMP regardless of allergy status.Disclosures All Authors: No reported disclosures

Nonirritating skin test concentrations for ceftazidime and aztreonam in patients with a documented beta-lactam allergy

Beta-lactam antibiotics (β-LABs) are a predominant cause of immediate and nonimmediate drug hypersensitivity reactions (henceforth designated as IDHRs and NIDHRs). At present, skin tests (STs) with immediate and delayed readings occupy the first place to document such IDHRs and NIDHRs. Therefore, optimizing nonirritant concentrations (NICs) is critical to ascertain the best balance of sensitivity and specificity. Avoiding under- and overdiagnosis should not only improve antibiotic stewardship at the level of the individual patient, but also reduce the costs of our health systems.

Impact of Beta-lactam Allergy on Treatment of Outpatient Infections

PurposeThe most commonly reported medication allergies in the United States involve beta-lactam antibiotics, creating an important consideration for prescribers when choosing optimal treatment of infections. Currently, few data exist on outpatient prescribing patterns in response to patients with a beta-lactam allergy. This study sought to evaluate the appropriateness of outpatient antibiotic therapy in patients with documented beta-lactam allergies within a Veterans Affairs health care system to evaluate areas of improvement in prescribing practices. MethodsPatients receiving outpatient oral antibiotics were prospectively identified through real-time electronic alerts from June 2017 through February 2018. Prescriptions were then reviewed retrospectively to identify appropriateness of antibiotic, drug choice, dose, and duration based on current guideline recommendations. Data were compared between patients with a listed beta-lactam allergy and patients without a beta-lactam allergy to determine the impact on prescribing patterns and outcomes. Baseline characteristics were compared by using descriptive statistics. Significant risk factors for inappropriate prescribing were identified through a multivariable analysis. FindingsThe cohort included 1844 antibiotic prescriptions (documented beta-lactam allergy, 221; no beta-lactam allergy, 1623). Appropriate drug, dose, and duration for antibiotics prescribed in patients reporting a beta-lactam allergy versus nonallergic patients were 44.3% versus 53.0% (P = 0.02), 91.4% versus 86.2% (P = 0.03), and 75.1% versus 76.2% (P = 0.83), respectively. Patients with a reported beta-lactam allergy were 31% less likely to receive the correct drug for indication empirically (95% CI, 0.52–0.92) in the multivariable regression model when adjusted for fluoroquinolone use. In addition, patients reporting a beta-lactam allergy were 2.2 times (95% CI, 1.6–3.0) more likely to receive a fluoroquinolone antibiotic. Antibiotics were considered overall inappropriate based on at least one aspect of therapy in 79.6% of patients reporting a beta-lactam allergy and in 71% of nonallergic patients. ImplicationsAntibiotic therapy in patients with a documented beta-lactam allergy was less likely to be appropriate overall, suggesting an area of improvement for prescribing habits. Future interventions should focus on prescriber education regarding first-line and alternative treatments for patients with beta-lactam allergies to ensure that optimal treatment is being provided.

Inappropriate Use of Aztreonam.

Aztreonam is not a preferred empiric antibiotic because of variable susceptibilities compared with alternative agents. In addition, it has no Gram-positive activity, necessitating coadministration with vancomycin when used empirically, and is more costly when compared with other Gram-negative active agents. Aztreonam is often given to patients with a reported penicillin allergy without further investigation into the reaction or other relevant allergy information. How frequently is aztreonam being used inappropriately? We conducted a retrospective chart review at an academic medical center to assess the appropriateness of our aztreonam use. Our primary outcome was frequency of appropriate aztreonam use, based on a true IgE-mediated allergy reported for each patient. We evaluated whether the patients had tolerated a beta-lactam in the past, and what the reported allergic reaction was. We included 165 patients and found that 46.7% of our aztreonam use was inappropriate, based on previous use of a beta-lactam, or no documentation of an IgE-mediated response. Of the patients with a documented beta-lactam allergy, 63 (38.2%) patients had no allergy manifestation listed, and 37 (22.4%) patients had a non-IgE-mediated allergy manifestation. Of the total population, 61 (37%) patients had tolerated a beta-lactam in the past. Aztreonam should be avoided, except in the case of a true IgE-mediated allergic reaction. Our goal was to reduce the inappropriate use of aztreonam at our institution by one or more of the following: educating providers, reviewing aztreonam orders, requiring answering of order questions, or requiring an indication for use. Penicillin skin testing and desensitization are options as well.

Pharmacy driven assessment of appropriate antibiotic selection in patients with reported beta‐lactam allergy

AbstractBackgroundReported beta‐lactam (BL) antibiotic allergies lead to the avoidance of BL antibiotics. Despite that less than 10% of patients reporting have a true allergy, the documentation often leads to an increased use of alternative antibiotics. These nonpreferred antibiotics (NPA) have a significant impact on cost, clinical outcomes, and antimicrobial resistance.ObjectiveThe primary objective of this study was to assess the impact of a pharmacy‐driven assessment on the prescribing frequency of penicillin or cephalosporin antibiotics in patients with a reported BL allergy.MethodsThis retrospective cohort analysis evaluated the effect of a best practice alert (BPA) and subsequent allergy assessment on BL use in patients with reported allergies at an integrated health system. The BPA notified pharmacy staff that a patient with a documented BL allergy was receiving a NPA. Pharmacy staff assessed previous BL tolerance and clarified reaction, severity, and timing of the documented allergy. Patients were identified for analysis if they had a documented BL allergy within the electronic medical record and received at least one antibiotic during the study period.ResultsA total of 418 patients were included in this analysis (180 preimplementation, 238 postimplementation). In the pharmacy‐driven assessment group, BL antibiotic use increased by 12.9% (P = .008) in patients with a previously documented BL allergy with the largest use increase in 3rd/4th generation cephalosporins (P = .045). Days of therapy for NPAs decreased in the postimplementation group, including aztreonam (P = .006) and vancomycin (P = .009).ConclusionsOur data suggests that a pharmacy‐driven allergy assessment using a BPA can increase appropriate use of BL antibiotics for hospitalized patients.

Effectiveness of empiric aztreonam compared to other beta-lactams for treatment of &lt;em&gt;Pseudomonas aeruginosa&lt;/em&gt; infections

PurposeTo evaluate the use of aztreonam as an active empiric therapy against subsequent culture of Pseudomonas aeruginosa (P. aeruginosa).MethodsThis was a retrospective cohort study conducted among patients who received either aztreonam or an antipseudomonal beta-lactam (BL) as an empiric therapy with subsequent culture with P. aeruginosa. All patients with at least one positive culture for P. aeruginosa between January 2014 and August 2016 were included in this analysis. The primary composite outcome was empiric therapy failure, defined as inappropriate empiric therapy, alteration of empiric antibiotic following culture results, or 30-day in-hospital mortality. Secondary outcomes included appropriate empiric therapy, alteration of empiric therapy, 30-day-in-hospital mortality, and post-culture hospital length of stay.ResultsThe primary outcome of empiric therapy failure was significantly higher in the aztreonam group than in the BL group (77.8% vs 41.9%; P=0.004). The aztreonam group had a lower rate of appropriate empiric therapy compared with the BL group (44.4% vs 66.1%; P=0.074) and higher alteration of empiric therapy once susceptibilities were known than when compared with the BL group (61.1%vs 28.2%; P=0.005). Although numerically higher, 30-day-in-hospital mortality and median hospital length of stay were not significantly different between the two groups.ConclusionEmpiric therapy failure occurred more often when initially using aztreonam vs a BL in a patient who subsequently had a P. aeruginosa infection. Only a third of patients within the aztreonam group had a documented BL allergy, demonstrating an inclination for clinicians to utilize this drug as an empiric therapy when there were more appropriate therapies available.

Appropriateness of Beta-Lactam Allergy Record Updates After an Allergy Service Consult

Background: Many patients with a self-reported penicillin allergy go on to tolerate beta-lactam antibiotics. Allergy specialists may be consulted to determine the nature and extent of the allergy. However, electronic allergy records must be appropriately updated such that recommendations are carried forward. Objective: To determine the percentage of patients who have their electronic allergy record updated after an allergy service consult (ASC). Methods: This was a retrospective study of patients with at least 1 documented beta-lactam allergy and had an ASC during (inpatient) or prior to (outpatient) hospital admission at Northwestern Memorial Hospital and Prentice Women’s Hospital in Chicago, Illinois. Results: Within the study period, a total of 26 526 patients were identified as having a documented antibiotic allergy, with 21 657 patients (81.6% of patients with allergies) having a listed beta-lactam allergy. Of these patients, 1689 (7.8%) patients were identified as having an ASC during or prior to admission, with 598 patients meeting inclusion criteria. Changes in the allergy record were recommended by the ASC for 62% (n = 371) of patients; however, the allergy record was updated after the ASC in 74.9% (n = 278) of patients. Conclusion: ASC recommendations to delabel a patient as beta-lactam allergic must result in updating the allergy record in order to optimize future treatment. Given the low proportion of allergy-labeled patients tested, programs outside formal ASCs should be considered.

Prevalence of beta-lactam allergy: a retrospective chart review of drug allergy assessment in a predominantly pediatric population.

BackgroundResearch suggests that 90% of patients labeled beta-lactam allergic are able to tolerate penicillins following further assessment. This study aims to define and describe the frequency of true beta-lactam allergy following allergy patient evaluation in a predominantly pediatric population.Methods306 primary care patients referred between January 2010 and June 2015 were assessed for a suspected beta-lactam allergy. Patient demographics, history and test results were extracted from electronic medical records. Testing performed was based on specialist recommendation following review of patient history.Results34% of the study participants had intradermal testing. Oral challenge was given to 96.7% of the sample. 96% of patients with a prior history of beta-lactam allergy were advised that they could re-introduce beta-lactam antibiotics following evaluation.ConclusionsAmong patients with a documented beta-lactam allergy or a recent history of a reaction there is a low rate of ‘true’ beta-lactam allergy. Consistent evaluation of beta-lactam antibiotic allergies can reduce rates of broad spectrum antibiotic prescribing, among other harmful consequences.

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

ObjectivesTo determine the impact of a pharmacist-driven beta-lactam allergy interview on antimicrobial therapy. SettingTertiary care academic medical center. Practice settingClarification of beta-lactam allergy may expand treatment options for patients and potentially improve outcomes, reduce toxicity, and reduce costs. Practice innovationAt our institution, a pilot service using a pharmacy resident and infectious diseases clinical pharmacist was implemented to clarify beta-lactam allergy information and, where appropriate, recommend a change to the patient’s antibiotic therapy. EvaluationAdult patients with a documented beta-lactam allergy who had received non-penicillin antibiotics and who had undergone a beta-lactam allergy interview were identified via pharmacy intervention data. A pharmacist interviewed these patients with the use of an internally developed allergy questionnaire. Recommendations for beta-lactam therapy were made to the patient’s primary medical team based on the results of the allergy interview and factors including infection type and culture results. The primary objectives were to determine the percentage of patients successfully switched to beta-lactam therapy as a result of the drug allergy interview, to identify allergy discrepancies between the electronic medical record (EMR) and pharmacist’s interview, and to quantify the acceptance rate of the pharmacist’s antimicrobial recommendations after drug allergy clarification. ResultsThirty-two patients were interviewed, and 24 were candidates for a beta-lactam recommendation. As a result of the interview, 21 patients (65.6%) were successfully switched from a non-penicillin antibiotic to a cephalosporin, carbapenem, or penicillin. A discrepancy between the EMR-reported allergy and history obtained on interview was identified in 11 patients (34.4%). Medical providers accepted 87.5% of pharmacists’ antimicrobial recommendations. ConclusionA pharmacist-driven beta-lactam allergy interview was effective in switching eligible patients to beta-lactam therapy and identifying discrepancies between EMR-documented allergies and confirmed allergies. Antimicrobial recommendations were well received by medical providers with a high acceptance rate.

Documenting Penicillin Allergy: The Impact of Inconsistency.

BackgroundAllergy documentation is frequently inconsistent and incomplete. The impact of this variability on subsequent treatment is not well described.ObjectiveTo determine how allergy documentation affects subsequent antibiotic choice.DesignRetrospective, cohort study.Participants232,616 adult patients seen by 199 primary care providers (PCPs) between January 1, 2009 and January 1, 2014 at an academic medical system.Main MeasuresInter-physician variation in beta-lactam allergy documentation; antibiotic treatment following beta-lactam allergy documentation.Key Results15.6% of patients had a reported beta-lactam allergy. Of those patients, 39.8% had a specific allergen identified and 22.7% had allergic reaction characteristics documented. Variation between PCPs was greater than would be expected by chance (all p<0.001) in the percentage of their patients with a documented beta-lactam allergy (7.9% to 24.8%), identification of a specific allergen (e.g. amoxicillin as opposed to “penicillins”) (24.0% to 58.2%) and documentation of the reaction characteristics (5.4% to 51.9%). After beta-lactam allergy documentation, patients were less likely to receive penicillins (Relative Risk [RR] 0.16 [95% Confidence Interval: 0.15–0.17]) and cephalosporins (RR 0.28 [95% CI 0.27–0.30]) and more likely to receive fluoroquinolones (RR 1.5 [95% CI 1.5–1.6]), clindamycin (RR 3.8 [95% CI 3.6–4.0]) and vancomycin (RR 5.0 [95% CI 4.3–5.8]). Among patients with beta-lactam allergy, rechallenge was more likely when a specific allergen was identified (RR 1.6 [95% CI 1.5–1.8]) and when reaction characteristics were documented (RR 2.0 [95% CI 1.8–2.2]).ConclusionsProvider documentation of beta-lactam allergy is highly variable, and details of the allergy are infrequently documented. Classification of a patient as beta-lactam allergic and incomplete documentation regarding the details of the allergy lead to beta-lactam avoidance and use of other antimicrobial agents, behaviors that may adversely impact care quality and cost.

Identifying opportunities in EHR to improve the quality of antibiotic allergy data.

Antimicrobial resistance is a growing, global public health crisis, due in large part to the overuse and misuse of antibiotics. Understanding medication allergy data and allergy reactions that are documented in electronic health records (EHRs) can help to identify opportunities to improve the quality of documentation of beta-lactam allergies, thus potentially reducing the prescribing of alternative antibiotics. Medication allergies and allergy reactions recorded in the EHR for 319 051 patients seen across 32 community health centers were reviewed. Patients with a beta-lactam allergy recorded in their EHR were identified. Free text, as well as standardized allergy and allergy reaction fields, were analyzed. Among patients, 9.1% (n = 29 095) had evidence of a beta-lactam allergy recorded in their EHR. Women, white, and non-Hispanic patients were more likely to have a documented allergy compared to men, black, and Hispanic patients. Among all patients with a documented beta-lactam allergy, 36.2% had an empty or missing allergy reaction description in their EHR. Findings suggest that current EHR documentation practices among the health centers reviewed do not provide enough information on allergic reactions to allow providers to discern between true allergies and common, but anticipated, drug side effects. Improved EHR documentation guidance, training that reinforces the use of standardized data and more detailed recording of allergic reactions, combined with initiatives to address patient barriers including health literacy, may help to improve the accuracy of drug allergies in patients' records. These initiatives, combined with antimicrobial stewardship programs, can help to reduce inappropriate prescribing of alternative antibiotics when beta-lactam antibiotics are first-line and can be tolerated.