Rates of paclitaxel hypersensitivity reactions using a modified Markman's infusion protocol as primary prophylaxis.

PURPOSE: Markman's desensitisation protocol allows successful retreatment of patients who have had significant paclitaxel hypersensitivity reactions. We aimed to reduce the risk and severity of paclitaxel hypersensitivity reactions by introducing this protocol as primary prophylaxis. METHODS: We evaluated all patients with a gynaecological malignancy receiving paclitaxel before (December 2018 to September 2019) and after (October 2019 to July 2020) the implementation of a modified Markman's desensitisation protocol. The pre-implementation group received paclitaxel over a gradually up-titrated rate from 60 to 180 ml/h. The post-implementation group received paclitaxel via 3 fixed-dose infusion bags in the first 2 cycles. Rates and severity of paclitaxel hypersensitivity reactions were compared. RESULTS: A total of 426 paclitaxel infusions were administered to 78 patients. The median age was 64 years (range 34-81), and the most common diagnosis was ovarian, fallopian tube and primary peritoneal cancer (67%, n = 52/78). Paclitaxel hypersensitivity reaction rates were similar in the pre-implementation (8%, n = 16/195) and post-implementation groups (9%, n = 20/231; p = 0.87). Most paclitaxel hypersensitivity reactions occurred within 30 min (pre- vs. post-implementation, 88% [n = 14/16] vs. 75% [n = 15/20]; p = 0.45) and were grade 2 in severity (pre- vs. post-implementation, 81% [n = 13/16] vs. 75% [n = 15/20]; p = 0.37). There was one grade 3 paclitaxel hypersensitivity reaction in the pre-implementation group. All patients were successfully rechallenged in the post-implementation group compared to 81% (n = 13/16) in the pre-implementation group (p = 0.43). CONCLUSION: The modified Markman's desensitisation protocol as primary prophylaxis did not reduce the rate or severity of paclitaxel hypersensitivity reactions, although all patients could be successfully rechallenged.

Is a low dose of dexamethasone sufficient to prevent paclitaxel-related hypersensitivity reactions? A retrospective study in patients with gynecologic malignancy.

BACKGROUND: Paclitaxel hypersensitivity reactions (HSRs) are prevalent, especially in females. The common paclitaxel pretreatment, dexamethasone, may inhibit chemotherapy efficacy and accelerate tumor progression. We aimed to balance paclitaxel HSRs and the lowest dexamethasone dose for gynecologic malignancies. METHODS: We retrospectively examined 1,074 cycles of 3-weekly paclitaxel-containing treatment for 231 gynecologic malignancies at Xiangya Hospital. HSR incidence with different dexamethasone regimens was the primary outcome. Risk factors were examined in all cycles using univariate and multivariate models with generalized estimating equations. A subgroup analysis of initial exposure to paclitaxel was also conducted. RESULTS: HSR occurred in 33 patients (14.29%) and 49 cycles (4.56%), including 69.39% in cycles 1-2. There were no severe HSRs (grade ≥3). Different premedication regimens, including dexamethasone dosage and route, ranitidine presence or absence, didn't affect HSR incidence in univariate and multivariate analyzes (p > 0.05). Premenopausal women exerted fewer HSRs (ORadj 0.22, 95%CI 0.08-0.58; p = 0.002). At the first exposure to paclitaxel, more than 10 mg of dexamethasone didn't diminish HSRs (OR 0.83, 95%CI 0.27-2.59; p = 0.753). CONCLUSIONS: In gynecologic malignancies, 10 mg dexamethasone along with 20 mg diphenhydramine may be adequate to prevent paclitaxel HSRs without ranitidine. It is necessary to reevaluate paclitaxel premedication regimens.

A nurse-driven penicillin allergy risk score in the preoperative setting was associated with increased cefazolin use perioperatively.

STUDY OBJECTIVE: To characterize and assess the effects of a preoperative, nurse-driven penicillin allergy risk stratification tool on rates of perioperative cefazolin and second-line antibiotic use. DESIGN: Quasi-experimental quality improvement study of penicillin-allergic surgical patients undergoing procedures for which cefazolin is indicated. SETTING: Outpatient Perioperative Care Clinic (PCC) for preoperative surgical patients at a tertiary care center. PATIENTS: 670 and 1371 adult penicillin-allergic PCC attendants and non-attendants, respectively. INTERVENTION: A paper penicillin allergy risk stratification questionnaire was administered during the PCC visit. Nurses were educated on its use. MEASUREMENTS: Antibiotic (cefazolin, clindamycin, vancomycin) use rates in the 24 months before and 17 months after intervention implementation in November 2020 (November 2018 - April 2022) were assessed in penicillin-allergic PCC attendants with statistical process control charts. Multivariable logistic regression assessed antibiotic use rates pre- and post-intervention adjusting for age, sex, surgical specialty and penicillin allergy history severity. Similar analyses were done in penicillin-allergic PCC non-attendants. MAIN RESULTS: Of 670 penicillin-allergic PCC attendants, 451 (median [IQR] age, 66 (Sousa-Pinto et al., 2021 [14])) were analyzed pre-intervention and 219 (median [IQR] age, 66 (Mine et al., 1970 [13])) post-intervention. One month after implementation, process measures demonstrated an upward shift in cefazolin use for PCC attendants versus no shift or other special cause variation for PCC non-attendants. There were increased odds of cefazolin use (aOR 1.67, 95% CI [1.09-2.57], P = 0.019), decreased odds of clindamycin use (aOR 0.61, 95% CI [0.42-0.89], P = 0.010) and decreased odds of vancomycin use (aOR 0.56, 95% CI [0.35-0.88], P = 0.013) in PCC attendants post-intervention. This effect did not occur in PCC non-attendants. There was no increase in perioperative anaphylaxis post-intervention. CONCLUSIONS: A simple penicillin allergy risk stratification tool implemented in the preoperative setting was associated with increased use of cefazolin and decreased rates of second-line agents post implementation.

Are changes in antibiotic prophylaxis recommendations responsible for an increased risk of cefazolin allergy?

BACKGROUND: The first line of prevention of surgical site infection relies on the timely administration of antibiotic prophylaxis. First- and second-generation cephalosporins are the most recommended antibiotics in elective surgery. The incidence of cefazolin allergy has increased worldwide over the years. The sensitization mechanism of cefazolin is currently unknown, and data supporting cross-reactivity between penicillins and cephalosporins are lacking. Sensitization could occur through previous exposure either to cefazolin or to structurally related chemical agents. The objective of this study was to evaluate sensitization agents towards cefazolin. METHODS: The OpenBabel chemoinformatics toolbox was used to search for similarities between cefazolin and other molecules in an extensive drug database. Using the pholcodine-rocuronium similarity score as a threshold, we selected drugs with the most similar structure to that of cefazolin. Exposure to those drugs and cefazolin was assessed in a cohort of patients with skin test-proven cefazolin allergy at a specialized allergy centre via a self-administered anonymous questionnaire. RESULTS: Using the pholcodine-rocuronium similarity score as a threshold (score≥0.7), 42 molecules were found to be similar to cefazolin (all cephalosporins). Only 8 were marketed in France. None of the 14 cefazolin-allergic patients who answered the questionnaire (65% female, median age 56 years) reported exposure to any identified antibiotics. In contrast, 11 (78%) had at least one previous surgery requiring cefazolin before the index case. CONCLUSION: Direct previous cefazolin exposure was identified in 78% of cefazolin-allergic patients. Cefazolin started to take a central place in antibiotic prophylaxis after 2010, when cefamandole usage decreased drastically. Changes in antibiotic prophylaxis over the past 14 years in France could have been the turning point for the increased incidence of cefazolin allergy.

Impact of institutional interventions on the rate of paclitaxel hypersensitivity reactions.

PURPOSE: Paclitaxel is associated with hypersensitivity reactions (HSRs). Intravenous premedication regimens have been devised to decrease the incidence and severity of HSRs. At our institution oral histamine 1 receptor antagonists (H1RA) and histamine 2 receptor antagonists (H2RA) were adopted as standard. Standardizations were implemented for consistent premedication use in all disease states. The purpose of this retrospective study was to compare the incidence and severity of HSRs before and after standardization. METHODS: Patients who received paclitaxel from 20 April 2018 to 8 December 2020 having an HSR were included in analysis. An infusion was flagged for review if a rescue medication was administered after the start of the paclitaxel infusion. The incidences of all HSR prior to and post-standardization were compared. A subgroup analysis of patients receiving paclitaxel for the first and second time was performed. RESULTS: There were 3499infusions in the pre-standardization group and 1159infusions in the post-standardization group. After review, 100 HSRs pre-standardization and 38 HSRs post-standardization were confirmed reactions. The rate of overall HSRs was 2.9% in the pre-standardization group and 3.3% in the post-standardization group (p = 0.48). HSRs, during the first and second doses of paclitaxel, occurred in 10.2% of the pre-standardization and 8.5% of the post-standardization group (p = 0.55). CONCLUSIONS: This retrospective interventional study demonstrated that same-day intravenous dexamethasone, oral H1RA, and oral H2RA are safe premedication regimens for paclitaxel. No change in the severity of reactions was seen. Overall, better adherence to premedication administration was seen post-standardization.

A Process Improvement Project to Increase Compliance With Cephalosporin-based Surgical Antimicrobial Prophylaxis in Children With Non-severe Penicillin Allergies.

BACKGROUND/PURPOSE: Cephalosporins are considered safe and first-line prophylaxis in children with non-severe penicillin allergies. However, use of second-line agents is common and is primarily driven by poor allergic response documentation and misunderstanding of cross-reactivity risk. The goal of this project was to improve compliance with cephalosporin prophylaxis through improved documentation and targeted educational efforts. METHODS: A multidisciplinary working group including representatives from allergy, surgery, infectious disease, and pharmacy developed staged interventions to facilitate compliance with cephalosporin prophylaxis. These included: (1) caregiver outreach to clarify incomplete allergy documentation, (2) a decision-support algorithm for prophylaxis use in penicillin-allergic patients, (3) standardized educational resources for surgical faculty and rotating trainees, (4) email reminders with prophylaxis recommendations sent out prior to scheduled cases, and (5) EMR-based decision support during antibiotic ordering. Rates of complete allergy documentation and cephalosporin utilization were compared for general surgery procedures between a 12-month pre-intervention and 14-month post-intervention period. RESULTS: 578 patients with penicillin allergies recorded in the EMR were included (301 pre-intervention and 277 post-intervention), 54.0% of which received prophylaxis. Compared to the pre-intervention period, complete documentation of allergic reactions increased from 57.1% to 84.2% (p < 0.001) following implementation of all interventions. Appropriate prophylaxis utilization increased from 34.5% to 88.5% following implementation of all interventions (p < 0.001), and evidence of a stepwise increase in appropriate utilization was evident with each intervention stage. Persistent compliance failures during the post-implementation period were most commonly associated with urgent and emergent add-on cases. No adverse events or allergic responses were reported before or after project implementation. CONCLUSIONS: Compliance with cephalosporin prophylaxis significantly improved following a multidisciplinary effort targeting education, allergy documentation, and clinical support at the point of care. Ongoing efforts include postoperative audits within 24 h for noncompliant cases in order to identify barriers and improve compliance for urgent and emergent add-on cases. LEVEL OF EVIDENCE: III. TYPE OF STUDY: Prospective.

Premedication strategy in cetuximab rechallenge after Grade 2 hypersensitivity reactions.

INTRODUCTION: Cetuximab, an IgG1 monoclonal antibody, is utilized in the treatment of metastatic colorectal cancer and squamous cell head and neck cancers. Due to the risk of hypersensitivity reactions, standard premedication with a histamine-1 (H-1) antagonist is recommended prior to administration, however, there is less guidance for premedication strategies to assist with rechallenge after infusion reactions. Here, we describe two cases of successful cetuximab treatment after Grade 2 reactions, in addition to risk factors and proposed premedication strategies for successful rechallenge. CASE REPORT: Two patients who experienced Grade 2 hypersensitivity reactions were both successfully rechallenged with increased premedications 1-2 weeks after initial infusions. The first patient was a 56-year-old male diagnosed with metastatic colorectal cancer receiving cetuximab as part of a clinical trial. The second patient was a 73-year-old male diagnosed with head and neck cancer receiving cetuximab as part of standard of care concurrent with radiation. MANAGEMENT AND OUTCOME: Each patient was rechallenged with an increased premedication strategy including dexamethasone, famotidine, diphenhydramine, and acetaminophen in addition to reducing the infusion rate. Both patients either continued treatment or successfully completed therapy, without any additional infusion-related reactions. DISCUSSION: We aimed to review risk factors related to cetuximab infusion reactions and propose a premedication strategy for rechallenge postreaction. Known risk factors include male sex and the accumulation of cetuximab-specific IgE. These may be mitigated by the addition of increased premedication with dexamethasone and famotidine with concurrent reduced infusion rate.

Low-risk penicillin allergy delabeling: a scoping review of direct oral challenge practice, implementation, and multi-disciplinary approaches.

INTRODUCTION: Penicillin allergy is common, and there is increased clinician interest in direct oral challenge (DOC) as a testing strategy for low-risk penicillin allergy. To aid wider implementation of DOC, consensus definitions of low-risk penicillin allergy phenotypes, and standardized approaches to assessment, DOC procedures, and evaluation, are required. AREAS COVERED: This review systematically reviews studies that have utilized penicillin DOC in healthcare settings to identify heterogeneity in implementation approaches and synthesize low-risk definitions, procedures, and evaluation. EXPERT OPINION: Opportunity exists to standardize penicillin DOC procedures in patients with a low-risk penicillin allergy to optimize antimicrobial prescribing and reduce the burden of penicillin allergy. Standardizing the definitions of 'low-risk' and 'positive challenge,' and improving the evaluation of patient safety, alongside the development of a unified approach to the structure of undertaking an oral challenge, is likely to increase uptake and confidence among non-allergist clinicians.

Beyond the override: Using evidence of previous drug tolerance to suppress drug allergy alerts; a retrospective study of opioid alerts.

OBJECTIVE: Despite the extensive literature exploring alert fatigue, most studies have focused on describing the phenomenon, but not on fixing it. The authors aimed to identify data useful to avert clinically irrelevant alerts to inform future research on clinical decision support (CDS) design. METHODS: We conducted a retrospective observational study of opioid drug allergy alert (DAA) overrides for the calendar year of 2019 at a large academic medical center, to identify data elements useful to find irrelevant alerts to be averted. RESULTS: Overall, 227,815 DAAs were fired in 2019, with an override rate of 91 % (n = 208196). Opioids represented nearly two-thirds of these overrides (n = 129063; 62 %) and were the drug class with the highest override rate (96 %). On average, 29 opioid DAAs were overridden per patient. While most opioid alerts (97.1 %) are fired for a possible match (the drug class of the allergen matches the drug class of the prescribed drug), they are overridden significantly less frequently for definite match (exact match between allergen and prescribed drug) (88 % vs. 95.9 %, p < 0.001). When comparing the triggering drug with previously administered drugs, override rates were equally high for both definite match (95.9 %), no match (95.5 %), and possible match (95.1 %). Likewise, when comparing to home medications, overrides were excessively high for possible match (96.3 %), no match (96 %), and definite match (94.4 %). CONCLUSION: We estimate that 74.5% of opioid DAAs (46.4% of all DAAs) at our institution could be relatively safely averted, since they either have a definite match for previous inpatient administrations suggesting drug tolerance or are fired as possible match with low risk of cross-sensitivity. Future research should focus on identifying other relevant data elements ideally with automated methods and use of emerging standards to empower CDS systems to suppress false-positive alerts while avoiding safety hazards.

Is ranitidine necessary as premedication for regimens containing paclitaxel? A non-inferiority study.

BACKGROUND: Histamine type-2-receptor antagonist drugs (H2-antagonists) have been used as standard treatment to prevent hypersensitivity reactions (HRs) in paclitaxel-containing regimens, however, their use has been strongly questioned. Ranitidine has been the most widely used H2-antagonist. Therefore, especially after its withdrawal from the market, the objective of this study is to determine the impact of its elimination from premedication on HR incidence. METHODS: A cohort, multicenter, observational, prospective, and non-inferiority study, including paclitaxel-naïve cancer patients, designed to determine the incidence of HRs of any grade associated with paclitaxel administration and analyze non-inferiority against the incidence estimated in the literature (20%), with 5% as the maximum difference (Δ). Patients with a solid neoplasm of any type/stage, who initiated treatment with paclitaxel without H2-antagonists in the premedication regimen were enrolled. RESULTS: A total of 441 patients were included, of whom 50 presented 54 HRs of any grade. The cumulative incidence was 11.3% (95%CI 8.5-14.7), thus fulfilling the hypothesis of non-inferiority. Of the overall HRs detected, 15 were grade ≥ 3 with a cumulative incidence of 3.4% (95%CI 1.9-5.5). CONCLUSIONS: This study demonstrates that the elimination of ranitidine from paclitaxel premedication schedules is non-inferior in the development of HRs of any grade compared to the administration of H2-antagonists.

Hypersensitivity to gadolinium-based contrast.

PURPOSE OF REVIEW: The use of contrast media is increasing in recent decades. Although gadolinium-based contrast agents (GBCAs) are generally well tolerated, adverse reactions, including hypersensitivity reactions (HSRs), although infrequent, may occur. It is important to perform a thorough allergological evaluation in patients with suspected GBCA-HSRs to avoid potentially serious reactions in subsequent exposures. RECENT FINDINGS: Data on GBCA-HSRs are scarce. Most published articles dealing with skin tests and drug provocation tests (DPTs) with GBCAs are case series and small cohorts. Controversies exist about the role of premedication for preventing HSRs on subsequent exposures. Selection of well tolerated alternatives is based on potential cross-reactivity among GBCAs; however, the extent of cross-reactivity among them remains unclear. SUMMARY: As premedication is not useful because breakthrough reactions are frequent in patients with GBCA-HSRs in subsequent exposures, an allergological evaluation is required. Available data suggest a high negative predictive value of skin tests, being crucial for guiding the selection of an alternative GBCA. However, DPTs are still necessary to confirm or exclude the diagnosis or find alternative GBCAs. Cross-reactivity is high among GBCAs belonging from the same group, mainly among macrocyclic compounds, so this must be taken into account for selecting alternatives.

A pharmacist-led penicillin allergy de-labelling project within a preoperative assessment clinic: the low-hanging fruit is within reach.

BACKGROUND: Having a false penicillin-allergy label is linked to longer hospital stays and to an increased risk of Clostridioides difficile and meticillin-resistant Staphylococcus aureus infection. AIM: To assess a penicillin-allergy de-labelling tool designed for use by the non-allergist. METHODS: Patients attending the surgical preoperative assessment clinic (POAC) at a large UK teaching hospital, who reported a penicillin allergy, were directly de-labelled by nursing or pharmacy staff, where appropriate. A penicillin-allergy de-labelling tool designed for use by the non-allergist was adapted and applied; nursing staff were provided with supporting information and education to enable removal of spurious labels. Antimicrobial pharmacists (AMPs) provided follow-up, cross-checked prophylactic antibiotics administered, interrogated clinical notes, and telephoned patients following their surgery, for details of any adverse reactions suffered. FINDINGS: A total of 163 patients reporting a penicillin allergy were identified for intervention. Twenty-nine (17.8%) patients reported a penicillin-allergy history appropriate for direct de-labelling, of whom eight (27.6%) declined to consent. The remaining 21 patients (12.8%) were directly de-labelled, with 12 (7.4%) patients consenting during their POAC appointment; the remaining nine (5.5%) patients were consented and de-labelled after their surgery by an AMP. CONCLUSION: The POAC was identified as an appropriate location and time-point in the patient pathway to enable the direct removal of spurious penicillin-allergy labels prior to surgery. Results suggest that this could be undertaken by nursing staff, although support from AMPs enabled a greater number of patients to be de-labelled.

Antibiotic choice for Group B Streptococcus prophylaxis in mothers with reported penicillin allergy and associated newborn outcomes.

OBJECTIVE: To evaluate the choice of antibiotic used for intrapartum Group B Streptococcus (GBS) prophylaxis in pregnant individuals with reported penicillin allergies compared to those without reported penicillin allergies and investigate whether there are associated differences in neonatal outcomes. STUDY DESIGN: This retrospective cohort study included mother-infant dyads of GBS positive pregnant individuals who labored and delivered newborns ≥ 35 weeks of gestation at a high-volume urban hospital (2005-2018). The type of antibiotic administered to the mothers for GBS prophylaxis (beta-lactam prophylaxis defined as penicillin-class drug or cefazolin; alternative prophylaxis defined as vancomycin or clindamycin) was compared between those with a penicillin allergy documented in their medical record versus those who did not. Neonatal outcomes included number of postnatal blood draws, antibiotic administration, neonatal intensive care unit (NICU) admission, bacteremia, and hospital length of stay and were compared between groups. Bivariable and multivariable analyses were performed. RESULTS: Of 11,334 mother-infant pairs, 1170 (10.3%) mothers had a penicillin allergy documented in their medical record. Of them, 49 (4.2%) received a penicillin, 259 (22.1%) received cefazolin, 449 (38.4%) received clindamycin, and 413 (35.3%) received vancomycin. Patients with a reported penicillin allergy were significantly more likely to receive alternative GBS prophylaxis compared to those without penicillin allergy (73.7% vs. 0.2%, p < 0.01). Neonates of patients who received alternative GBS prophylaxis were significantly more likely to undergo a postnatal lab draw compared to neonates of patients who received beta-lactam antibiotics (20.8% vs. 17.3%, OR 1.25 (95% CI 1.08-1.46)). This significant association persisted after adjusting for potential confounders (aOR 1.23, 95% CI 1.06-1.43). There were no other significant differences seen in other newborn outcomes. CONCLUSION: Pregnant individuals who report a penicillin allergy were more likely to receive alternative antibiotics for GBS prophylaxis compared to those without a penicillin allergy. This was associated with an increased frequency of postnatal blood draws among neonates of mothers with a reported penicillin allergy. Administration of alternative intrapartum antibiotic prophylaxis with vancomycin or clindamycin is common in individuals with self-reported penicillin allergy, and maternal alternative antibiotic administration may impact neonatal care, particularly via increased lab draws.

Optimizing Cefazolin Prophylaxis in Obstetrical Patients with Reported Beta-Lactam Allergy Undergoing Cesarean Delivery.

OBJECTIVES: Evaluate the impact of an allergy history-guided algorithm for optimizing perioperative cefazolin use in patients with reported beta-lactam allergy undergoing cesarean delivery. METHODS: The Allergy Clarification for Cefazolin Evidence-based Prescribing Tool (ACCEPT) was developed through consensus by allergists, anesthesiologists, and infectious diseases specialists, and implemented over a 2-month period (December 1, 2018, to January 31, 2019). A segmented regression on monthly cefazolin use was conducted during the baseline (January 1 to November 30, 2018) and intervention (February 1 to December 31, 2019) periods to evaluate the impact of ACCEPT on the monthly use of perioperative cefazolin in patients with reported beta-lactam allergy undergoing cesarean delivery. The frequency of perioperative allergic reactions and surgical site infections was collected during both periods. RESULTS: Of the 3128 eligible women who underwent a cesarean delivery, 282 (9%) reported a beta-lactam allergy. The most common beta-lactam allergens were penicillin (64.3%), amoxicillin (16.0%), and cefaclor (6.0%). The most frequently reported allergic reactions were rash (38.1%), hives (21.4%), and unknown (11.6%). Use of cefazolin increased from 52% (baseline) to 87% during the intervention period. Segmented regression analysis confirmed a statistically significant increase following implementation (incidence rate ratio 1.62, 95% CI 1.19-2.21, P = 0.002). There was 1 perioperative allergic reaction in the baseline period and 2 during the intervention period. Cefazolin use remained high (92%) 2 years after algorithm implementation. CONCLUSIONS: Implementation of a simple allergy history-guided algorithm in obstetrical patients with reported beta-lactam allergy resulted in a sustained increase in perioperative cefazolin prophylaxis.

An interdisciplinary student-led multifaceted intervention addressing overuse of broad-spectrum antibiotics for patients with penicillin allergies.

BACKGROUND: Though 15% of hospitalized patients have a documented penicillin (PCN) allergy, fewer than 1% have an IgE-mediated reaction that necessitates avoidance of ß-lactam antibiotics. OBJECTIVE: Our interdisciplinary team of medical and nursing students led and executed a two-pronged quality improvement intervention to reduce prescribing of non-ß-lactam antibiotics (NBLs) for patients with reported PCN allergies. To the best of our knowledge, this is the first multidisciplinary student-led intervention aimed at educating providers on low-risk penicillin allergy and encouraging best antibiotic prescribing practices. DESIGN AND PARTICIPANTS: The intervention took place from June 2021 to February 2022. We developed and provided clinician education modules, including peer-to-peer information sharing and in-person small group discussions, as well as clinical decision support (CDS) strategies through the electronic medical record (EMR). The target population was attendings, residents, nurse practitioners, and physician assistants on the hospital medicine service at a large urban academic tertiary care center. We followed the SQUIRE 2.0 guidelines for reporting on quality improvement. MAIN MEASURES: Primary outcome measures included number of NBL prescriptions and use of nonspecific descriptors (e.g., "other" or "unknown") for PCN allergy reaction type, and were compared with a pre-intervention period. KEY RESULTS: The percent of ß-lactam prescriptions for patients with a PCN allergy after the intervention increased from 19 to 23% (p = 0.006). For patients with a low severity PCN allergy, the percent of ß-lactam prescriptions increased from 20 to 28% (p = 0.001). There was a significant decrease in nonspecific PCN allergy reaction type from 23% in the pre-intervention period to 20% post-intervention (p = 0.012). CONCLUSIONS: An intervention focused on educating prescribers and CDS strategies delivered through the EMR increased appropriate ß-lactam prescribing for patients with a documented low-risk PCN allergy and reduced the use of nonspecific PCN allergy reaction type in EMR documentation.

A Three-Step Taxane Titration Protocol Decreases Hypersensitivity Reactions During First and Second Exposures.

INTRODUCTION: Patients receiving taxanes are at risk for developing hypersensitivity reactions (HSRs) primarily during first and second lifetime exposures. Immediate HSRs require emergency care and can interfere with the continuation of preferred treatment. Although different approaches to slow titration have been used successfully for desensitization after HSR occurrence, there are no standardized recommendations for taxane titration to prevent HSRs. PURPOSE: To determine if a gradual, three-step infusion rate titration decreases the rate and severity of immediate HSRs during first and second lifetime exposures to paclitaxel and docetaxel. METHODS: We used a prospective, interventional design with historical comparisons to evaluate a sample of 222 first and second lifetime exposure paclitaxel and docetaxel infusions. The intervention was a three-step infusion rate titration provided at the initiation of first and second lifetime exposures. Ninety-nine titrated infusions were compared with 123 historical records of nontitrated infusions. RESULTS: Compared with the nontitrated group (n = 123), the titrated group (n = 99) had significantly less HSRs (19% v 7%; P = .017). No significant difference in HSR severity was found between groups (P = 1.00). However, four nontitrated patients received epinephrine, and one required transfer to the emergency department (ED) because of reaction severity. In contrast, no titrated patients received epinephrine or required transfer to the ED. In the nontitrated group, seven patients did not complete their infusions versus one patient in the titrated group. CONCLUSION: A standardized, three-step infusion rate titration prevented HSR occurrence. Significant issues affecting practice feasibility and sustainability were addressed.

Contrast Agent Selection to Prevent Recurrent Severe Hypersensitivity Reaction to Iodinated Contrast Media Based on Nationwide Database.

OBJECTIVE: To investigate the incidence of severe iodinated contrast media (ICM)-related hypersensitivity reaction (HSR) and to find the optimal alternative ICM to reduce the risk of severe HSR recurrence. METHODS: We retrospectively reviewed 23,383,183 cases of ICM administration between January 2015 and December 2019 from the nationwide health insurance database. We classified ICMs based on generic profiles and the presence of N-(2,3-dihydroxypropyl) carbamoyl side chains. The incidence of severe and recurrent severe HSRs was calculated, and χ2 tests were performed to compare the prevalence of severe HSR according to ICM groups. In addition, logistic regression analyses were used to assess differences between ICM groups. RESULTS: The incidence of severe HSRs was 1.92% (450,067 of 23,282,183). Among 1,875,245 individuals who received ICM twice on different days, severe HSR occurred in 40,850 individuals, and severe HSR recurred in 3319 individuals (8.12%). The risk of recurrence significantly decreased when the ICM changed (9.24% vs 7.08%, P < 0.001), especially when the ICM changed to one with a different side chain (6.74%, P < 0.001). In addition, compared with the reuse of the culprit agent, using combinations of iobitridol/iohexol (odds ratio [OR], 0.696; P = 0.04), iohexol/iopamidol (OR, 0.757; P = 0.007), iopamidol/iohexol (OR, 0.447; P < 0.001), and ioversol/iohexol (OR, 0.683; P = 0.04) reduced the risk of recurrence of severe HSR. CONCLUSIONS: Changing the culprit ICM to that with a different side chain can reduce severe HSR recurrence. The optimal choice of an alternative ICM depends on the causative agent.