The Impact of a Reported Penicillin Allergy on Surgical Site Infection Risk

Perioperative Infection Prophylaxis With Vancomycin is a Significant Risk Factor for Deep Surgical Site Infection in Spine Surgery

STUDY DESIGN

Retrospective cohort.

OBJECTIVE

The purpose of this study was to compare the efficacy of cefazolin versus vancomycin for perioperative infection prophylaxis.

SUMMARY OF BACKGROUND DATA

The relative efficacy of cefazolin alternatives for perioperative infection prophylaxis is poorly understood.

MATERIALS AND METHODS

This study was a single-center multisurgeon retrospective review of all patients undergoing primary spine surgery from an institutional registry. Postoperative infection was defined by the combination of three criteria: irrigation and debridement within 3 months of the index procedure, clinical suspicion for infection, and positive intraoperative cultures. Microbiology records for all infections were reviewed to assess the infectious organism and organism susceptibilities. Univariate and multivariate analyses were performed.

RESULTS

A total of 10,122 patients met inclusion criteria. The overall incidence of infection was 0.78%, with an incidence of 0.73% in patients who received cefazolin and 2.03% in patients who received vancomycin (OR: 2.83, 95% CI: 1.35-5.91, P= 0.004). Use of IV vancomycin (OR: 2.83, 95% CI: 1.35-5.91, P =0.006), BMI (MD: 1.56, 95% CI: 0.32-2.79, P =0.014), presence of a fusion (OR: 1.62, 95% CI: 1.04-2.52, P =0.033), and operative time (MD: 42.04, 95% CI: 16.88-67.21, P =0.001) were significant risk factors in the univariate analysis. In the multivariate analysis, only noncefazolin antibiotics (OR: 2.48, 95% CI: 1.18-5.22, P =0.017) and BMI (MD: 1.56, 95% CI: 0.32-2.79, P =0.026) remained significant independent risk factors. Neither IV antibiotic regimen nor topical vancomycin significantly impacted Gram type, organism type, or antibiotic resistance ( P >0.05). The most common reason for antibiosis with vancomycin was a penicillin allergy (75.0%).

CONCLUSIONS

Prophylactic antibiosis with IV vancomycin leads to a 2.5 times higher risk of infection compared with IV cefazolin in primary spine surgery. We recommend the routine use of IV cefazolin for infection prophylaxis, and caution against the elective use of alternative regimens like IV vancomycin unless clinically warranted.

Evaluation of antibiotic prescribing patterns for surgical prophylaxis before and after an educational campaign about penicillin allergies: a single-center, retrospective study

After an educational campaign about reasonable use of cefazolin for surgical prophylaxis, optimal preoperative antibiotic regimen utilization increased from 52% to 67% (P = 0.011). Education to physicians on penicillin allergies may contribute to meaningful increases in use of optimal antibiotics while reducing readmissions and acute care length of stay.

Impacts of risk-stratified inpatient penicillin allergy label delabeling on subsequent antimicrobial spectrum index and costs

Penicillin allergy delabeling may benefit antimicrobial stewardship (AS). Cost of initial penicillin treatments following risk-stratified inpatient delabeling were compared to two hypothetical treatment regimens if delabeling had not occurred: (1) AS-guided and (2) Common Treatment. Penicillin allergy delabeling improved antimicrobial spectrum index, was cost-neutral, and averted unnecessary penicillin desensitizations.

Cefazolin as the mainstay for antibiotic prophylaxis in patients with a penicillin allergy in obstetrics and gynecology

Cefazolin is the most common antibiotic used for prophylaxis in obstetrics and gynecology. Among those with a penicillin allergy, alternative antibiotics are often chosen for prophylaxis, given fears of cross-reactivity between penicillin and cefazolin. Alternative antibiotics in this setting are associated with adverse sequelae, including surgical site infection, induction of bacterial resistance, higher costs to the healthcare system, and possible Clostridium difficile infection. Given the difference in R1 side chains between penicillin and cefazolin, cefazolin use is safe and should be recommended for patients with a penicillin allergy, including those who experience Immunoglobulin E-mediated reactions such as anaphylaxis. Cefazolin should only be avoided in those who experience a history of a severe, life-threatening delayed hypersensitivity reaction manifested as severe cutaneous adverse reactions (Steven-Johnson Syndrome), hepatitis, nephritis, serum sickness, and hemolytic anemia in response to penicillin administration. In addition, >90% of those with a documented penicillin allergy do not have true allergies on skin testing. Increased referral for penicillin allergy testing should be incorporated into routine obstetric care and preoperative assessment to reduce suboptimal antibiotic prophylaxis use. More education is needed among providers surrounding penicillin allergy assessment and cross-reactivity among penicillins and cephalosporins to optimize antibiotic prophylaxis in obstetrics and gynecology.

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.

Postoperative infections after sinus lifts and onlay grafts in penicillin allergic patients

INTRODUCTION

The primary objective of this retrospective study was to determine whether patients treated with clindamycin due to a reported allergy to penicillin have an increased risk of postsurgical infections after sinus lifts and onlay grafts.

MATERIAL AND METHODS

A retrospective cohort study was performed on patients who underwent bone reconstruction procedures between October 2018 and December 2020. Data from all patients operated at the Pitié Salpêtrière University Hospital for sinus lifts or onlay grafts were collected. All surgical procedures studied were performed under preoperative and postoperative antibiotic prophylaxis with either amoxicillin (+/- clavulanic acid) or clindamycin for patients with reported penicillin allergy. Bone graft-associated infections as well as graft failures were recorded.

RESULTS

In this study, 111 patients received bone reconstructions (89 sinus lifts and 148 onlay grafts). In the sinus lifts group, infections occurred in 5 of 89 sites (5.6 %). The infection rate was 28.5 % (7 graft sites) and only 3.9 % (82 graft sites) for clindamycin and for amoxicillin, respectively. In the onlay graft group, infections occurred in 25 of 148 sites (16.8 %). The infection rate was 56 % and only 12 % for clindamycin (18 graft sites) and for amoxicillin, respectively (130 graft sites). Non-Penicillin treated patients had a higher risk of infection with an odd ratio of 7.8 (95 % CI 1.1-54.8, P = 0.04) and 4.8 (95 % CI 1.9-12.3, P = 0.001) compared with patients receiving amoxicillin for onlay grafts and sinus lifts.

CONCLUSION

Penicillin allergy and clindamycin use after sinus lift and onlay graft procedures were associated with a higher rate of infection and may be a risk factor for complications related to bone reconstruction surgery.

The Polyanalgesic Consensus Conference (PACC)®: Intrathecal Drug Delivery Guidance on Safety and Therapy Optimization When Treating Chronic Noncancer Pain

INTRODUCTION

The International Neuromodulation Society convened a multispecialty group of physicians and scientists based on expertise with international representation to establish evidence-based guidance on intrathecal drug delivery in treating chronic pain. This Polyanalgesic Consensus Conference (PACC)® project, created more than two decades ago, intends to provide evidence-based guidance for important safety and efficacy issues surrounding intrathecal drug delivery and its impact on the practice of neuromodulation.

MATERIALS AND METHODS

Authors were chosen on the basis of their clinical expertise, familiarity with the peer-reviewed literature, research productivity, and contributions to the neuromodulation literature. Section leaders supervised literature searches of MEDLINE, BioMed Central, Current Contents Connect, Embase, International Pharmaceutical Abstracts, Web of Science, Google Scholar, and PubMed from 2017 (when PACC® last published guidelines) to the present. Identified studies were graded using the United States Preventive Services Task Force criteria for evidence and certainty of net benefit. Recommendations are based on the strength of evidence or consensus when evidence is scant.

RESULTS

The PACC® examined the published literature and established evidence- and consensus-based recommendations to guide best practices. Additional guidance will occur as new evidence is developed in future iterations of this process.

CONCLUSIONS

The PACC® recommends best practices regarding intrathecal drug delivery to improve safety and efficacy. The evidence- and consensus-based recommendations should be used as a guide to assist decision-making when clinically appropriate.

A call to address penicillin allergy labels in patients with hematopoietic stem cell transplants: How to avoid rash decisions

Among patients with hematopoietic stem cell transplants, infections, particularly multidrug-resistant infections, pose a grave threat. In this setting, penicillin allergy labels are both common and harmful. Though the majority of patients who report penicillin allergy can actually tolerate penicillin, penicillin allergy labels are associated with use of alternative antibiotics, which are often more broad spectrum, less effective, and more toxic. In turn, they are associated with more severe infections, multidrug-resistant infections, Clostridium difficile, and increased mortality. Evaluating penicillin allergy labels can immediately expand access to preferred therapeutic options, which are critical to care in patients with recent hematopoietic stem cell transplants. Point-of-care assessment and clinical decision tools now exist to aid the nonallergist in assessment of penicillin allergy. This can aid in expanding use of other beta-lactam antibiotics and assist in risk-stratifying patients to determine a testing strategy. In patients with low-risk reaction histories, direct oral challenges can be employed to efficiently delabel patients across clinical care settings. We advocate for multidisciplinary efforts to evaluate patients with penicillin allergy labels prior to transplantation.

Not a Benign (Mis)Label: Penicillin Allergy Education for the Nonallergist

Introduction

Up to 20% of the US population carries a penicillin allergy label; however, over 95% of those patients can safely tolerate penicillin. This discrepancy has important personal and public health consequences. There is no published curriculum for medical trainees that covers penicillin allergy history taking, risk assessment, and antibiotic prescribing.

Methods

We created a 60-minute, interactive curriculum that targeted medical students during their internal medicine rotation. We employed learning strategies including didactics, case-based learning, and role-playing. We compared self-efficacy and knowledge before and after the intervention using paired t tests.

Results

A total of 28 medical students participated, with 25 completing both the pre- and postworkshop surveys. There was a statistically significant improvement in student-rated preparedness to prescribe antibiotics to patients with a penicillin allergy label (p < .001) and determine whether a patient has a history of an allergic reaction that was severe or life-threatening (p < .001). There was additionally a statistically significant increase in students' perception that penicillin allergy labels carry important health consequences (p = .005), as well as increase in their total knowledge scores (p = .006).

Discussion

The workshop employs adult learning techniques to improve self-efficacy and knowledge regarding penicillin allergy in medical students. Further work is needed to refine the curriculum, seek external validity, and determine the impact of this workshop on clinical outcomes.

Implementation of a penicillin allergy protocol in open abdominal wall reconstruction: Preoperative optimization program

INTRODUCTION

Beta-lactam prophylaxis is the first-line preoperative antibiotic in open abdominal wall reconstruction. However, of the 11% patients reporting a penicillin allergy (PA), most receive second-line, non-β-lactam prophylaxis. Previously, abdominal wall reconstruction research from our institution demonstrated increased wound complications, readmissions, and reoperations with non-β-lactam prophylaxis. Therefore, a collaborative quality improvement initiative was developed with the infectious disease service, and a penicillin allergy protocol was instituted that stratified patients' risk of allergic reaction with a goal to increase β-lactam prophylaxis use. The effect of the penicillin allergy protocol on open abdominal wall reconstruction outcomes was prospectively evaluated.

METHODS

Patients with penicillin allergy undergoing open abdominal wall reconstruction were identified and grouped according to penicillin allergy protocol implementation. Pre-penicillin allergy protocol underwent open abdominal wall reconstruction before January 1, 2020, predominantly receiving non-β-lactam prophylaxis; post-penicillin allergy protocol underwent open abdominal wall reconstruction between January 1, 2020-November 1, 2023, predominantly receiving β-lactam prophylaxis. Incidence of surgical site infection was the primary outcome. Standard and inferential statistical analyses were performed.

RESULTS

Of 315 patients with penicillin allergy, 250 underwent open abdominal wall reconstruction pre-penicillin allergy protocol and 65 post-penicillin allergy protocol. Pre- and post-penicillin allergy protocol were similar in allergic reaction severity history, sex, race, age, diabetes, American Society of Anesthesiologists score, hernia defect size, and mesh type (P > .05). Post-penicillin allergy protocol had lower body mass index (33.4 ± 7.9 vs 29.8 ± 5.3 kg/m2; P = .002) and fewer active smokers (12.4% vs 1.5%; P = .019). Expectedly, post-penicillin allergy protocol received more β-lactam prophylaxis (22.8% vs 83.1%; P < .001) and no antibiotic-induced allergic reactions. Post-penicillin allergy protocol had significantly fewer surgical site infections (24.4% vs 3.1%; P < .001), wound breakdown (16.0% vs 3.1%; P = .004), reoperations (19.2% vs 0.0%; P < .001), and readmissions (25.3% vs 9.2%; P = .006) but no statistically significant reduction in recurrence (8.4% vs 1.5%; P = .057).

CONCLUSIONS

The penicillin allergy protocol safely increased the number of patients with penicillin allergy undergoing open abdominal wall reconstruction receiving β-lactam prophylaxis and decreased the rate of surgical site infections, wound complications, reoperations, and readmissions. These data supported the systemwide implementation of the penicillin allergy protocol for both general and orthopedic surgery, which has been incorporated into the electronic medical record of 13 hospitals within the system.

Evaluation of Suspected Antibiotic Allergies

This JAMA Clinical Guidelines Synopsis summarizes the 2022 recommendations on evaluation of suspected antibiotic allergies from the American Academy of Allergy, Asthma &amp;amp; Immunology and American College of Allergy, Asthma &amp;amp; Immunology.

A penicillin allergy stewardship team to address unconfirmed pediatric penicillin allergies in Houston, Texas

BACKGROUND

Penicillin (PCN) allergy labels are the most common drug allergy label and limit use of first-line antibiotics for many pediatric bacterial infections. Improving access to PCN allergy evaluations is a priority for allergy and immunology (A&I) and infectious diseases (ID) programs.

OBJECTIVE

To increase the number of completed PCN allergy evaluations from 6 to 24 per month from January 2022 to December 2023.

METHODS

A collaborative PCN allergy stewardship team was established in the A&I and ID divisions at Texas Children's Hospital. Telemedicine evaluations and, when clinically indicated, in-person PCN allergy evaluations were conducted from January 2022 to December 2023. Plan-do-study-act cycles were conducted to increase awareness about the clinics. The primary outcome measure was the average number of monthly completed PCN allergy evaluations.

RESULTS

The average number of completed PCN allergy evaluations increased from 6 to 19 per month. Children were seen rapidly in the ID telemedicine clinic (20 vs 62 days, P < .001), and 428 of 627 (68%) children who required in-person challenge were scheduled for their in-person evaluation. Among the 211 children delabeled, 71 (33.6%) were subsequently diagnosed with a bacterial infection requiring PCN during the study period.

CONCLUSION

A collaborative PCN allergy stewardship team consisting of ID and A&I specialists increased the number of completed PCN allergy evaluations 3-fold. ID telemedicine services allowed prompt access to care, and most children were delabeled and subsequently able to receive PCN antibiotics for bacterial respiratory tract infections. Future work should explore ways to minimize barriers to PCN allergy evaluations and further expand testing services in other settings.

Factors influencing implementation and adoption of direct oral penicillin challenge for allergy delabelling: a qualitative evaluation

BACKGROUND

Over 95% of penicillin allergy labels are inaccurate and may be addressed in low-risk patients using direct oral penicillin challenge (DPC). This study explored the behaviour, attitudes and acceptability of patients, healthcare professionals (HCPs) and managers of using DPC in low-risk patients.

METHODS

Mixed-method, investigation involving patient interviews and staff focus groups at three NHS acute hospitals. Transcripts were coded using inductive and deductive thematic analysis informed by the Theoretical Domains Framework.

FINDINGS

Analysis of 43 patient interviews and three focus groups (28 HCPs: clinicians and managers) highlighted themes of 'knowledge', 'beliefs about capabilities and consequences', 'environmental context', 'resources', 'social influences', 'professional role and identity', 'behavioural regulation and reinforcement' and a cross-cutting theme of digital systems. Overall, study participants supported the DPC intervention. Patients expressed reassurance about being in a monitored, hospital setting. HCPs acknowledged the need for robust governance structures for ensuring clarity of roles and responsibilities and confidence.

CONCLUSION

There were high levels of acceptability among patients and HCPs. HCPs recognised the importance of DPC. Complexities of penicillin allergy (de)labelling were highlighted, and issues of knowledge, risk, governance and workforce were identified as key determinants. These should be considered in future planning and adoption strategies for DPC.

Metronidazole and cefazolin vs cefazolin alone for surgical site infection prophylaxis in gynecologic surgery at a comprehensive cancer center

BACKGROUND

Surgical site infection is one of the most common complications of gynecologic cancer surgery. Current guidelines recommend the administration of cefazolin preoperatively to reduce surgical site infection rates for patients undergoing clean-contaminated surgeries such as hysterectomy.

OBJECTIVE

To evaluate the impact of a quality improvement project adding metronidazole to cefazolin for antibiotic prophylaxis on surgical site infection rate for women undergoing gynecologic surgery at a comprehensive cancer center.

STUDY DESIGN

This retrospective, single-center cohort study included patients who underwent surgery in the gynecologic oncology department from May 2017 to June 2023. Patients with penicillin allergies and those undergoing concomitant bowel resections and/or joint cases were excluded. The preintervention group patients had surgery from May 2017 to April 2022, and the postintervention group patients had surgery from April 2022 to June 2023. The primary outcome was a 30-day surgical site infection rate. Sensitivity analyses were performed to compare surgical site infection rates on the basis of actual antibiotics received and for those who had a hysterectomy. Factors independently associated with surgical site infection were identified using a multivariable logistic regression model adjusting for confounding variables.

RESULTS

Of 3343 patients, 2572 (76.9%) and 771 (23.1%) were in the pre-post intervention groups, respectively. Most patients (74.7%) had a hysterectomy performed. Thirty-four percent of cases were for nononcologic (benign) indications. Preintervention patients were more likely to receive appropriate preoperative antibiotics (95.6% vs 90.7%; P<.001). The overall surgical site infection rate before the intervention was 4.7% compared with 2.6% after (P=.010). The surgical site infection rate for all patients who underwent hysterectomy was 4.9% (preintervention) vs 2.8% (postintervention) (P=.036); a similar trend was seen for benign cases (4.4% vs 2.4%; P=.159). On multivariable analysis, the odds ratio for surgical site infection was 0.49 (95% confidence interval, 0.38-0.63) for the postintervention compared with the preintervention group (P<.001). In a sensitivity analysis (n=3087), the surgical site infection rate was 4.5% for those who received cefazolin alone compared with 2.3% for those who received cefazolin plus metronidazole, with significantly decreased odds of surgical site infection for the cefazolin plus metronidazole group (adjusted odds ratio, 0.40 [95% confidence interval, 0.30-0.53]; P<.001). Among only those who had a hysterectomy performed, the odds of surgical site infection were significantly reduced for those in the postintervention group (adjusted odds ratio, 0.63 [95% confidence interval, 0.47-0.86]; P=.003).

CONCLUSION

The addition of metronidazole to cefazolin before gynecologic surgery decreased the surgical site infection rate by half, even after accounting for other known predictors of surgical site infection and differences in practice patterns over time. Providers should consider this combination regimen in women undergoing gynecologic surgery, especially for cases involving hysterectomy.

Perioperative Cefazolin for Total Joint Arthroplasty Patients Who Have a Penicillin Allergy: Is It Safe?

BACKGROUND

Cefazolin is the standard of care for perioperative antibiotic prophylaxis in total joint arthroplasty (TJA) in the United States. The potential allergic cross-reactivity between cefazolin and penicillin causes uncertainty regarding optimal antibiotic choice in patients who have a reported penicillin allergy (rPCNA). The purpose of this study was to determine the safety of perioperative cefazolin in PCNA patients undergoing primary TJA.

METHODS

We identified all patients (n = 49,842) undergoing primary total hip arthroplasty (n = 25,659) or total knee arthroplasty (n = 24,183) from 2016 to 2022 who received perioperative intravenous antibiotic prophylaxis. Patients who had an rPCNA (n = 5,508) who received cefazolin (n = 4,938, 89.7%) were compared to rPCNA patients who did not (n = 570, 10.3%), and to patients who did not have an rPCNA (n = 43,359). The primary outcome was the rate of allergic reactions within 72 hours postoperatively. Secondary outcomes included the rates of superficial infections, deep infections, and Clostridioides difficile infections within 90 days.

RESULTS

The rate of allergic reactions was 0.1% (n = 5) in rPCNA patients who received cefazolin, compared to 0.2% (n = 1) in rPCNA patients who did not (P = .48) and 0.02% (n = 11) in patients who have no rPCNA (P = .02). Allergic reactions were mild in all 5 rPCNA patients who received cefazolin and were characterized by cutaneous symptoms (n = 4) or dyspnea in the absence of respiratory distress (n = 1) that resolved promptly with antibiotic discontinuation and administration of antihistamines and/or corticosteroids. We observed no differences in the rates of superficial infections (0.1 versus 0.2%, P = .58), deep infections (0.3 versus 0.4%, P = .68), or C difficile infections (0.04% versus 0%, P = .99) within 90 days in rPCNA patients who received cefazolin versus alternative perioperative antibiotics.

CONCLUSIONS

In this series of more than 5,500 patients who had an rPCNA undergoing primary TJA, perioperative prophylaxis with cefazolin resulted in a 0.1% incidence of allergic reactions that were clinically indolent. Cefazolin can be safely administered to most patients, independent of rPCNA severity.

LEVEL OF EVIDENCE

III.

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.

Surgical prophylaxis in pediatric orthopedic patients with penicillin allergy: a multicentered retrospective prognostic study

Up to 20% of orthopedic surgeons still avoid the use of cephalosporins in patients with penicillin allergies despite its reported safety in the adult and general surgery pediatric population. The primary objective is to determine the incidence of adverse effects and allergic reactions when using cephalosporins in pediatric orthopedic patients labeled as penicillin-allergic as compared to those without previously reported penicillin allergy. A multicenter retrospective chart review was performed across three level 1 trauma centers from January 2013 to February 2020 to identify penicillin-allergic as well as non-penicillin-allergic pediatric patients treated for orthopedic injuries. Data were collected regarding patient demographics, antibiotic administered, timing of antibiotic administration, reported drug allergy, and described allergic reaction. Postoperative or intraoperative allergic reactions to antibiotics, surgical site infections, and complications were recorded. A total of 2289 surgeries performed by four fellowship-trained surgeons were evaluated. Eighty-five patients diagnosed with penicillin allergy were identified and underwent 95 surgeries and 95 patients without previously reported penicillin allergy underwent 95 surgeries. One patient, with a documented history of anaphylaxis to cefazolin, sustained an anaphylactic reaction intraoperatively to cefazolin. There were no other reported reactions, surgical site infections, or complications. There was no statistically significant difference in rate of allergic reaction in patients with previously reported penicillin allergy treated with cefazolin and those with no previous reported reaction ( P > 0.05). Prophylaxis with cephalosporins is not associated with increased risk for allergic reaction. Cephalosporins can be safely administered to pediatric patients with penicillin allergy undergoing orthopedic intervention. Level of evidence: Level II, Multicenter Retrospective Prognostic Study.

Evaluation of patients labeled with a penicillin allergy to promote antimicrobial stewardship in dental practice

BACKGROUND

Approximately 10% of the US population self-reports a penicillin allergy history or are labeled as penicillin allergic. However, from 90% through 99% of these patients are not allergic on formal evaluation.

CASE DESCRIPTION

Patients labeled as penicillin allergic receive broader-spectrum and sometimes less-effective antibiotics, thereby contributing to increased treatment failures, antibiotic resistance, and adverse drug reactions. Self-reported penicillin allergy can be eliminated or classified as low-, medium-, or high-risk after a careful review of patient history. This allows these patients to be delabeled; that is, having any reference to their penicillin allergy history or of having an allergy to penicillin eliminated from their health records.

PRACTICAL IMPLICATIONS

Oral health care professionals are ideally placed to partner in both antibiotic stewardship interventions by means of recognizing pervasive mislabeling and aiding in the process of delabeling.

[Penicillin allergy-Truth or duty?]

The beta-lactam antibiotics are some of the safest and best-tolerated antibiotic agents; however, many patients have reported allergies against penicillin. All beta-lactam antibiotics are only restrictively prescribed for these patients and alternative antibiotics are increasingly given, which carries the risk of negative clinical results and socioeconomic sequelae; however, over 95% of patients who reported an allergy to penicillin show a negative result in the allergy tests for penicillin and this antibiotic can safely be prescribed. The use of sensitive and specific instruments for identification of false penicillin allergies should be an important topic within the framework of antibiotic stewardship. Anesthesists can play a central role in the reduction of the enormous individual and public health burden associated with the classification of penicillin allergy by taking an appropriate medical history and a risk stratification for the identification of patients with a penicillin allergy. This overview article presents a possible delabelling algorithm within the framework of the clarification of a beta-lactam antibiotic allergy. The focus is on a structured allergy anamnesis using the penicillin allergy, five or fewer years ago, anaphylaxis/angioedema, severe cutaneous adverse reaction (SCAR) and treatment required for allergy episode (PEN-FAST) score.

Preoperative survey to evaluate the patients' allergy list and its relevance to perioperative care

INTRODUCTION

Perioperative hypersensitivity and allergic reactions can result in significant morbidity and mortality. For routine anesthetic care, allergies are determined from a review of the electronic medical record supplemented by a detailed patient history. Although the electronic medical record is generally assumed to be accurate, it may be that allergies are erroneously listed or not based on sound medical practice. The purpose of the current study is to evaluate allergies listed in the electronic medical record of children presenting for surgery and determine their origin, authenticity, and impact on perioperative care.

METHODS

Eligible patients included those presenting for a surgical procedure in the main operating room, who were ≤ 21 years of age, with a drug allergy listed on the EMR. Prior to intraoperative care, an electronic survey questionnaire containing questions related to medication allergies was provided to a guardian or parent. Two anesthesiology physicians reviewed the survey responses to determine the validity of any reported allergies. A second electronic survey was given postoperatively to the attending anesthesiologist to determine whether the documented allergy impacted anesthetic care.

RESULTS

The study cohort included 250 patients, ranging in age from 5 to 14 years (median age 9 years). All of the patients had at least one allergy listed on the electronic medical record. Seventy of the 250 patients (28%) had more than one drug allergy listed for a total of 351 medication allergies. The majority of the listed allergies were related to antibiotics including 155 (44%) from the penicillin family, 26 (7%) cephalosporins, 16 (5%) sulfonamides, and 36 (10%) other antimicrobial agents. Other commonly listed allergies were 27 (8%) nonsteroidal anti-inflammatory agents and 15 (4%) opioids. The remaining 76 (22%) included a miscellaneous list of other medications. On further review of the allergies, the survey was completed for 301 medications. After physician review, 135 of 301 (45%) responses were considered consistent with IgE reactions "true allergy," 73 (24%) were deemed less relevant to IgE reactions "unlikely true allergy," and 93 (31%) were not related to IgE reactions "not an allergy." Care alterations during surgery were uncommon regardless of whether the issue was assessed as a true allergy (11%), unlikely to be a true allergy (3%), or not a true allergy (13%).

CONCLUSION

A significant portion of the documented allergies in children are not true allergies, but rather recognized adverse effects (apnea from an opioid, renal failure from an NSAIDs) or other nonallergic concerns (gastrointestinal upset such as nausea). Erroneously listed allergies may lead to unnecessary alterations in patient care during perioperative care. A careful analysis of the allergy list on the EMR should be supplemented by a thorough patient history with specific questions related to the drug allergy. Once this is accomplished, the allergy listed should be updated to avoid its erroneous impact on perioperative care.

Examining cefazolin utilization and perioperative anaphylaxis in patients with and without a penicillin allergy label: A cross-sectional study

STUDY OBJECTIVE

To compare the occurrence of cefazolin perioperative anaphylaxis (POA) in patients with and without a penicillin allergy label (PAL) to determine whether the prevalence of cefazolin POA differs based on the presence of a PAL.

DESIGN

Cross-sectional study.

SETTING

A large U.S. healthcare system in the Baltimore-D.C. region, July 2017 to July 2020.

PATIENTS

112,817 surgical encounters across inpatient and outpatient settings in various specialties, involving 90,089 patients. Of these, 4876 (4.3%) encounters had a PAL.

INTERVENTIONS

Perioperative cefazolin administration within 4 h before surgery to 4 h after the procedure began.

MEASUREMENTS

The primary outcome was cefazolin POA in patients with and without PALs. Potential POA cases were identified based on tryptase orders or diphenhydramine administrations within the initial cefazolin administration to 6 h postoperatively. Verification included two validation steps. The first checked for hypersensitivity reaction (HSR) documentation, and the second, led by Allergy specialists, identified POA and the probable culprit. The secondary outcome looked at cefazolin use trends in patients with a PAL, stratified by setting and specialty.

MAIN RESULTS

Of 112,817 encounters, 1421 (1.3%) had possible cefazolin HSRs. Of these, 22 (1.5%) had POA, resulting in a 0.02% prevalence. Of these, 13 (59.1%) were linked to cefazolin and 9 (40.9%) attributed to other drugs. Only one cefazolin POA case had a PAL, indicating no significant difference in cefazolin POA prevalence between patients with and without PALs (p = 0.437). Perioperative cefazolin use in patients with PALs steadily increased from 2.6% to 6.0% between 2017 and 2020, specifically in academic settings.

CONCLUSIONS

The prevalence of cefazolin POA does not exhibit significant differences between patients with and without PALs, and notably, the incidence remains remarkably low. Based on these findings, it is advisable to view cefazolin as an acceptable choice for prophylaxis in patients carrying a PAL.

Quality corner: Safely using cephalosporins in almost all patients with penicillin allergies: Mini-review and suggested protocol to improve efficacy and surgical outcomes

Surgical site infections (SSI) are one of the most common gynecologic oncology postoperative complications and they have a significant deleterious impact on the healthcare system and in patients' outcomes. Cefazolin is the recommended antibiotic in women undergoing gynecologic surgical procedures that require that require prophylaxis. However, 10-20% of patients may report a penicillin allergy which can result in administration of a less effective antibiotic. This quality review evaluated the literature around this common perioperative issue and demonstrated that healthcare teams should consider the implementation of a protocol to safely use cefazolin in most patients with a penicillin allergy. Overall, literature shows this is a safe adjustment and would improve antimicrobial stewardship, decrease SSI rates, avoid acute kidney injury, and increase cost savings.

Is Penicillin Allergy a Clinical Problem? A Systematic Review of Total Joint Arthroplasty Procedures With Implications for Patient Safety and Antibiotic Stewardship

BACKGROUND

Patients undergoing total joint arthroplasty (TJA) who report penicillin allergy (PA) are frequently administered second-line antibiotics, although recent evidence suggests that this may be unnecessary and could increase infection risk. Many institutions have aimed to improve antibiotic deployment via allergy testing and screening; however, there is little standardization to this process. This review aimed to evaluate (1) antibiotic selection in patients who report PA and assess the impact of screening and testing interventions, (2) rates of allergic reactions in patients who report PA, and (3) the association between reported PA and screening or testing programs and odds of surgical site infection or periprosthetic joint infection.

METHODS

PubMed, EBSCOhost, and Google Scholar electronic databases were searched on February 4, 2023 to identify all studies published since January 1, 2000 that evaluated the impact of PA on patients undergoing TJA (PROSPERO study protocol registration: CRD42023394031). Articles were included if full-text manuscripts in English were available, and the study analyzed the impact of PA and related interventions on TJA patients. There were 11 studies evaluating 1,276,663 patients included. Interventions were compared via presentation of key findings regarding rates of clinically relevant or high-risk PA reported upon screenings or testings, cephalosporin utilizations, allergic reactions, and postoperative infections (surgical site infection and periprosthetic joint infection).

RESULTS

All 6 studies found that PA screening and testing markedly increase the use of first-line antibiotics. Testing showed low rates of true allergy (0.7 to 3%) and allergic reaction frequency for patients who have reported PA receiving cephalosporins was between 0% and 2%. Although there were mixed findings across studies, there was a trend toward second-line antibiotic prophylaxis being associated with a slightly higher rate of infection in PA patients.

CONCLUSIONS

Using PA screening and testing can promote antibiotic stewardship by safely increasing the use of first-line antibiotics in patients who have a reported PA.

LEVEL OF EVIDENCE

Level III, Therapeutic Study.

β-Lactam allergy delabeling is safe and saves costs in Primary Care

OBJECTIVE

To determine whether the β-lactam allergy delabeling was safe and cost-saving in Primary Care (PC) patients.

DESIGN

We have conducted a retrospective chart review of PC patients with β-lactam allergy label evaluated in our Allergy Unit between 2017 and 2022. SITE: Allergy Department. Hospital Virgen del Rocio (Sevilla).

PARTICIPANTS

A total of 391 patients labeled for β-lactam allergy in PC were studied.

MAIN MEASUREMENTS

(a) Outcome evaluation of a β-lactam allergy delabeling procedure. (b) A ratio between the total e-prescribed antibiotic cost and the number of treatment days (the experimental daily antibiotic cost or EDAC) before and after delabeling was analyzed in delabeled and truly allergic patients.

RESULTS

The results of skin testing were positive in 9.2% of the reported cases (36 of 391 patients). The reactions to oral provocation challenge (OPC) occurred in 2.14% of the patients who underwent negative skin testing to offending β-lactam (in 15 of 699 OPC). A total of 307 patients (78.5%) were delabeled; 70 (17.9%) had a β-lactam selective response and 14 (3.59%) reacted to both penicillin and cephalosporin. The EDAC before and after the procedure in delabeled patients was significantly lower (0.88 € vs 0.62 €, p<10-3), than that observed in truly allergic group (0.87 € vs. 0.76 €, p=not significant).

CONCLUSION

To delabel β-lactam allergy in Primary Care patients is safe in most patients, cost-saving in antibioticotherapy, and allows identify the main clinical β-lactam allergy phenotypes that benefit from this procedure.

Randomized Multicenter Trial for the Validation of an Easy-to-Administer Algorithm to Define Penicillin Allergy Status in Sexually Transmitted Infection Clinic Outpatients

BACKGROUND

Approximately 15% of patients in sexually transmitted infection (STI) clinics report penicillin allergies, complicating treatment for syphilis and gonorrhea. Nonetheless, >90% do not have a penicillin allergy when evaluated. We developed and validated an algorithm to define which patients reporting penicillin allergy can be safely treated at STI clinics with these drugs.

METHODS

Randomized controlled trial to assess feasibility and safety of penicillin allergy evaluations in STI clinics. Participants with reported penicillin allergy answered an expert-developed questionnaire to stratify risk. Low-risk participants underwent penicillin skin testing (PST) followed by amoxicillin 250 mg challenge or a graded oral challenge (GOC)-amoxicillin 25 mg followed by 250 mg. Reactions were recorded, and participant/provider surveys were conducted.

RESULTS

Of 284 participants, 72 (25.3%) were deemed high risk and were excluded. Of 206 low-risk participants, 102 (49.5%) underwent PST without reactions and 3 (3%) had mild reactions during the oral challenge. Of 104 (50.5%) participants in the GOC, 95 (91.3%) completed challenges without reaction, 4 (4.2%) had mild symptoms after 25 mg, and 4 (4.2%) after 250-mg doses. Overall, 195 participants (94.7%) successfully completed the study and 11 (5.3%) experienced mild symptoms. Of 14 providers, 12 (85.7%) completed surveys and 11 (93%) agreed on the safety/effectiveness of penicillin allergy assessment in STI clinics.

CONCLUSIONS

An easy-to-administer risk-assessment questionnaire can safely identify patients for penicillin allergy evaluation in STI clinics by PST or GOC, with GOC showing operational feasibility. Using this approach, 67% of participants with reported penicillin allergy could safely receive first-line treatments for gonorrhea or syphilis. Clinical Trials Registration. Clinicaltrials.gov (NCT04620746).

Predicting Penicillin Allergy: A United States Multicenter Retrospective Study

BACKGROUND

Using the reaction history in logistic regression and machine learning (ML) models to predict penicillin allergy has been reported based on non-US data.

OBJECTIVE

We developed ML positive penicillin allergy testing prediction models from multisite US data.

METHODS

Retrospective data from 4 US-based hospitals were grouped into 4 datasets: enriched training (1:3 case-control matched cohort), enriched testing, nonenriched internal testing, and nonenriched external testing. ML algorithms were used for model development. We determined area under the curve (AUC) and applied the Shapley Additive exPlanations (SHAP) framework to interpret risk drivers.

RESULTS

Of 4777 patients (mean age 60 [standard deviation: 17] years; 68% women, 91% White, and 86% non-Hispanic) evaluated for penicillin allergy labels, 513 (11%) had positive penicillin allergy testing. Model input variables were frequently missing: immediate or delayed onset (71%), signs or symptoms (13%), and treatment (31%). The gradient-boosted model was the strongest model with an AUC of 0.67 (95% confidence interval [CI]: 0.57-0.77), which improved to 0.87 (95% CI: 0.73-1) when only cases with complete data were used. Top SHAP drivers for positive testing were reactions within the last year and reactions requiring medical attention; female sex and reaction of hives/urticaria were also positive drivers.

CONCLUSIONS

An ML prediction model for positive penicillin allergy skin testing using US-based retrospective data did not achieve performance strong enough for acceptance and adoption. The optimal ML prediction model for positive penicillin allergy testing was driven by time since reaction, seek medical attention, female sex, and hives/urticaria.

How to Define and Manage Low-Risk Drug Allergy Labels

Risk stratification in drug allergy implies that specific risk categories (eg, low, moderate, and high) classify historical drug hypersensitivity reactions. These risk categories can be based on reaction phenotypic characteristics, the timing of the reaction and evaluation, the required reaction management, and individual characteristics. Although a multitude of frameworks have been described in the literature, particularly for penicillin allergy labels, there has yet to be a global consensus, and approaches continue to vary between allergy centers. Immune-mediated drug allergies can sometimes be confirmed using skin testing, but a negative drug challenge is required to demonstrate tolerance and remove the allergy from the electronic health record ("delabel" the allergy). Even for quintessential IgE-mediated drug allergy, penicillin allergy, recent data reveal that a direct oral challenge, without prior skin testing, is an appropriate diagnostic strategy in those who are considered low-risk. Drug allergy pathogenesis and clinical manifestations may vary depending on the culprit drug, and as such, the optimal approach should be based on risk stratification that considers individual patient and reaction characteristics, the likely hypersensitivity reaction phenotype, the drug class, and the patient's clinical needs. This article will describe low-risk drug allergy labels, focusing on β-lactam and sulfonamide antibiotics, nonsteroidal anti-inflammatory drugs, iodinated contrast media, and common chemotherapeutics. This review will also address practical management approaches using currently available risk stratification and clinical decision tools.

Beta-lactam antibiotics administration among adult inpatients with a beta-lactam allergy label: incidence, predictors, and outcomes

Background

A beta-lactam antibiotics (BLA) allergy label is common, resulting in disadvantageous outcomes due to the usage of second-line antimicrobial agents. Noncontrolled case-series analyses report low rates of hypersensitivity reactions, following intentional/non-intentional BLA challenges among labeled inpatients. The study aims were to explore predictors and outcomes associated with hypersensitivity reactions following BLA challenge among BLA-allergic labeled inpatients.

Methods

Retrospective cohort study (2019-2020) of adult (≥18 years) inpatients (Shamir Medical Center, Israel), labeled as allergic to ≥1 BLA, who received ≥1 dose/s of BLA during their stay. Independent predictors to develop allergic reactions and the independent associations of allergic reactions with clinical outcomes were queried by logistic and Cox regressions.

Results

Of 9,670 inpatients (14,088 hospitalizations), 3,570 (37%) were labeled as allergic to ≥1 BLA. Of those, 1,171 (33%) patients received ≥1 BLA. The majority were women (67%), and the mean age was 69.3 ± 19.4 years. Only 30 patients (2.6%) developed a reaction, all mild. Independent predictors to develop an allergic reaction were documented reactions in the past, atopic background, antihistamines administration prior to the BLA challenge, and high risk for cross-reactivity, based on the BLA side chains, between the labeled and the challenged agents. Reaction upon the BLA challenge was not independently associated with any worse outcome.

Conclusions

Despite the commonality of allergy labeling, and the commonality of BLA administration to labeled inpatients, hypersensitivity reactions were mild and rare. Interventional stewardship strategies for active BLA de-labeling among low-risk patients should be promoted, to improve patients' and institutional health and fiscal outcomes.

Diagnosis and Treatment of Perioperative Allergic Complications: A Practical Review

Background

Reported drug allergies are commonly encountered by surgeons and can lead to uncertainty in selecting an appropriate agent due to concerns of associated risks with related and cross-reactive drugs. This uncertainty can ultimately lead to increased infection rates.

Methods

A literature review was conducted in PubMed using a combination of the terms "allergy," "allergic reaction," "anaphylaxis," and "surgery," "surgical," or "operating room" for articles published within the last 10 years. Publications identified with these search terms were then filtered for review articles, sorted by "best match," and a maximum of 100 articles were manually reviewed for each combination of search terms.

Results

Search results yielded 46,484 articles, 676 of which were ultimately included for manual review, based on selection criteria. Specifically, articles selected for inclusion focused on surgical allergic reactions that were either related to mechanism of action, causative agent for the allergic reaction, timing of allergic reaction, or recommendations for appropriate management.

Conclusions

Allergic reactions can be a common occurrence in the operative room. Knowledge of likely causative agents, timing of a reaction to various agents, and appropriate management in the immediate and delayed setting can improve outcomes and safety for plastic surgery patients.

Risk factors for surgical site infection in patients undergoing obstetrics and gynecology surgeries: A meta-analysis of observational studies

OBJECTIVE

The aim of this study was to identify the risk factors for surgical site infection (SSI) in patients undergoing obstetrics and gynecology surgeries through meta-analysis.

METHODS

Relevant original studies published from January 1945 to May 2023 were searched the CBM, PubMed, Embase, WOS, CNKI, Wanfang, vip, and Cochrane Library databases. Studies eligible were evaluated by two investigators following Newcastle-Ottawa Scale(NOS) criteria. Review Manager 5.3 software was used to analyse the combined effect sizes and test for heterogeneity, and Stata 14.0 software's Begg's Test and Egger's Test were used to test for bias.

RESULTS

13 case-control articles, including 860 cases in the case group and 13574 cases in the control group, met the inclusion criteria. Eventually, Our meta-analysis showed that SSI in patients undergoing obstetrics and gynecology surgeries was correlated with body mass index (BMI)≥24 (OR = 2.66; P < 0.0001), malignant lesions (OR = 4.65; P < 0.0001), operating time≥60min (OR = 2.58; P < 0.0001), intraoperative bleeding≥300ml (OR = 2.54; P < 0.0001), retained urinary catheter (OR = 4.45; P < 0.0001), and vaginal digital examination≥3times (OR = 2.52; P < 0.0001).

CONCLUSION

In this study, BMI≥24, intraoperative bleeding≥300ml, malignant lesions, operating time≥60min, retained urinary catheter, and vaginal digital examination≥3times were considered as independent risk factors for SSI in obstetrics and gynecology surgery. It is recommended that scholars be rigorous in designing the experimental process when conducting case-control or experimental studies in order to improve the quality of the study. Controlling patients' weight before obstetrical and gynecological surgery, shortening the operation time intraoperatively, and strictly controlling the indications of vaginal digital examination and retained urinary catheter can effectively reduce the incidence of SSI.

Utility of beta-lactam allergy assessment in patients receiving vancomycin for surgical prophylaxis

Background

Beta-lactam antibiotics are first-line agents for most patients receiving antimicrobial prophylaxis in surgical procedures. Despite evidence showing low cross-reactivity between penicillins and cephalosporins, patients with beta-lactam allergies commonly receive vancomycin as an alternative to avoid allergic reaction.

Methods

Adult patients receiving vancomycin for surgical prophylaxis with a reported beta-lactam 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.

Results

Among 830 patients who received vancomycin for surgical prophylaxis, 196 reported beta-lactam allergy and were included in the analysis. Approximately 40 % of surgeries were orthopedic. Of patients receiving vancomycin as first-line therapy, 189 (96.4 %) were potentially eligible for beta-lactam prophylaxis.

Conclusions

Patients with beta-lactam allergies often qualify for receipt of a first-line antibiotic. An opportunity exists for improved allergy assessment as an antimicrobial stewardship intervention in surgical prophylaxis.

Management of Penicillin Allergy in the Perioperative Setting

The selection of perioperative antibiotic prophylaxis is challenging in patients with a history of penicillin allergy; as such, we present a literature review exploring current best practices and the associated supporting evidence, as well as areas for future research. Guidelines recommend the use of alternative agents in patients with an IgE-mediated hypersensitivity reaction, but those alternative agents are associated with worse outcomes, including an increased risk of surgical site infection, and higher cost. More recent data suggest that the risk of cross-reactivity between penicillins and cephalosporins, particularly cefazolin, is extremely low, and that cefazolin can be used safely in most penicillin-allergic patients. Studies have therefore explored how best to implement first-line cefazolin use in patients with a penicillin allergy label. A variety of interventions, including preoperative allergy de-labeling with incorporation of penicillin skin testing, use of patient risk-stratification questionnaires, and utilization of clinician algorithms to guide antibiotic selection intraoperatively, have all been shown to significantly increase cefazolin utilization without a corresponding increase in adverse events. Further studies are needed to clarify the most effective interventions and implementation strategies, as well as to evaluate whether patients with severe delayed hypersensitivity reactions to penicillin should continue to be excluded from receipt of other beta-lactams.

Impact of penicillin allergy labels on surgical site infections in a large UK cohort of gastrointestinal surgery patients

Objectives

Studies in the USA, Canada and France have reported higher surgical site infection (SSI) risk in patients with a penicillin allergy label (PAL). Here, we investigate the association between PALs and SSI in the UK, a country with distinct epidemiology of infecting pathogens and range of antimicrobial regimens in routine use.

Methods

Electronic health records and national SSI surveillance data were collated for a retrospective cohort of gastrointestinal surgery patients at Cambridge University Hospitals NHS Foundation Trust from 1 January 2015 to 31 December 2021. Univariable and multivariable logistic regression were used to examine the effects of PALs and the use of non-β-lactam-based prophylaxis on likelihood of SSI, 30 day post-operative mortality, 7 day post-operative acute kidney injury and 60 day post-operative infection/colonization with antimicrobial-resistant bacteria or Clostridioides difficile.

Results

Our data comprised 3644 patients and 4085 operations; 461 were undertaken in the presence of PALs (11.3%). SSI was detected after 435/4085 (10.7%) operations. Neither the presence of PALs, nor the use of non-β-lactam-based prophylaxis were found to be associated with SSI: adjusted OR (aOR) 0.90 (95% CI 0.65-1.25) and 1.20 (0.88-1.62), respectively. PALs were independently associated with increased odds of newly identified MRSA infection/colonization in the 60 days after surgery: aOR 2.71 (95% CI 1.13-6.49). Negative association was observed for newly identified infection/colonization with third-generation cephalosporin-resistant Gram-negative bacteria: aOR 0.38 (95% CI 0.16-0.89).

Conclusions

No evidence was found for an association between PALs and the likelihood of SSI in this large UK cohort, suggesting significant international variation in the impact of PALs on surgical patients.

Antibiotics in anesthesia and critical care

Sepsis is life-threatening organ dysfunction due to a dysregulated host response to an underlying acute infection. Sepsis is a major worldwide healthcare problem. An annual estimated 48.9 million incident cases of sepsis is reported, with 11 million (20%) sepsis-related deaths. Administration of appropriate antimicrobials is one of the most effective therapeutic interventions to reduce mortality. The severity of illness informs the urgency of antimicrobial administration. Nevertheless, even used properly, they cause adverse effects and contribute to the development of antibiotic resistance. Both inadequate and unnecessarily broad empiric antibiotics are associated with higher mortality and also select for antibiotic-resistant germs. In this narrative review, we will first discuss important factors and potential confounders which may influence the occurrence of surgical site infection (SSI) and which should be considered in the provision of perioperative antibiotic prophylaxis (PAP). Then, we will summarize recent advances and perspectives to optimize antibiotic therapy in the intensive care unit (ICU). Finally, the major role of the microbiota and the impact of antimicrobials on it will be discussed. While expert recommendations help guide daily practice in the operating theatre and ICU, a thorough knowledge of pharmacokinetic/pharmacodynamic (PK/PD) rules is critical to optimize the management of complex patients and minimize the emergence of multidrug-resistant organisms.

Clarification of adverse drug reactions by a pharmacovigilance team results in increased antibiotic re-prescribing at a freestanding United States children's hospital

Documentation of adverse drug reactions (ADRs) is a key factor in guiding future prescribing. However, incomplete documentation is common and often fails to distinguish implicated drugs as true allergies. This in turn leads to unnecessary avoidance of implicated drug classes and may result in sub-optimal prescribing. Pharmacovigilance (PV) programs utilize a systematic approach to clarify ADR documentation and are known to improve patient safety. Yet it remains unclear if PV alters prescribing. Or, if the existence of the ADR documentation itself continues to prompt avoidance of implicated drugs. To address this, our work presents a retrospective cohort study assessing if clarification of antibiotic ADRs by a hospital-wide PV team was associated with future, safe, re-prescribing at a freestanding pediatric hospital in the midwestern United States. First, we compared the likelihood of future prescribing in an antibiotic class with an active ADR, as compared to alternative drug classes, between PV-clarified and non-clarified patients. Second, we assessed differences in adverse event rates 30-days after future prescribing based on PV clarification status. For robustness, analyses were performed on patients with ADRs in four antibiotic classes: penicillin-based beta-lactams (n = 45,642), sulfonamides/trimethoprim (n = 5,329), macrolides (n = 3,959), and glycopeptides (n = 622). Results illustrate that clarification of an ADR by PV was associated with an increased odds of future prescribing in the same drug class (Odds Ratio [95%-CI]): penicillin-based beta-lactams (1.59 [1.36-1.89]), sulfonamides/trimethoprim (2.29 [0.89-4.91]), macrolides (0.77 [0.33-1.61]), and glycopeptide (1.85 [1.12-3.20]). Notably, patients clarified by PV experienced no increase in the rate of adverse events within 30-days following the prescribing of antibiotics in the same class as an active ADR. Overall, this study provides strong evidence that PV reviews safely increase the rate of re-prescribing antibiotics even in the presence of an existing implicated drug ADR.

Inpatient allergy delabeling of pediatric patients with low-risk penicillin allergy status through direct oral amoxicillin challenge

Background: Less than 5% of children who report penicillin allergy have clinically pertinent type 1 immunoglobulin E mediated hypersensitivity reaction by using direct oral amoxicillin challenge. Several pathways have been developed to delabel penicillin allergy by using direct oral amoxicillin challenge, mostly in the outpatient settings, but there is relative scarcity on published outcomes of these pathways, especially in the inpatient pediatric settings. Objective: This study aimed to evaluate the performance of an institutionally derived inpatient penicillin allergy screening tool. Methods: Patients were stratified into three penicillin allergy risk categories by using an institutional screening questionnaire. Patients with a no-risk status were delabeled without challenge testing. Patients with low-risk status underwent direct graded oral amoxicillin challenge and delabeled based on their response. Patients with high-risk status were referred to allergy service. Results: Ninety-two patients were identified with penicillin allergy. Forty of the 92 patients (43%) were screened. Of the 40 patients screened, 6 (15%) were identified as no risk, 28 (70%) were identified as low risk, and 6 (15%) were identified as high risk. Twenty-four of the 28 patients at low risk (86%) were eligible for direct amoxicillin oral challenge. Seventeen of the 24 (71%) consented to oral challenge but only 12 (71%) underwent direct amoxicillin oral challenge. Eleven of the 12 who underwent oral challenge (92%) were successfully delabeled. Five of the six patients at no risk (83%) were successfully delabeled. Three of the six patients at high risk (50%) were referred for further allergy evaluation. Overall, 16 of the 40 patients screened (40%) were successfully delabeled. Conclusion: In this small pediatric inpatient study, our institutional risk stratification screening tool identified patients at low risk for penicillin allergy and direct graded oral amoxicillin challenge was safely administered to delabel penicillin allergy in these patients.Clinical trial NCT05020327, www.clinicaltrials.gov.

Unpacking adverse events and associations post COVID-19 vaccination: a deep dive into vaccine adverse event reporting system data

INTRODUCTION

The rapid development of COVID-19 vaccines has provided crucial tools for pandemic control, but the occurrence of vaccine-related adverse events (AEs) underscores the need for comprehensive monitoring.

METHODS

This study analyzed the Vaccine Adverse Event Reporting System (VAERS) data from 2020-2022 using statistical methods such as zero-truncated Poisson regression and logistic regression to assess associations with age, gender groups, and vaccine manufacturers.

RESULTS

Logistic regression identified 26 System Organ Classes (SOCs) significantly associated with age and gender. Females displayed especially higher odds in SOC 19 (Pregnancy, puerperium and perinatal conditions), while males had higher odds in SOC 25 (Surgical and medical procedures). Older adults (>65) were more prone to symptoms like Cardiac disorders, whereas those aged 18-65 showed susceptibility to AEs like Skin and subcutaneous tissue disorders. Moderna and Pfizer vaccines induced fewer SOC symptoms compared to Janssen and Novavax. The zero-truncated Poisson regression model estimated an average of 4.243 symptoms per individual.

CONCLUSION

These findings offer vital insights into vaccine safety, guiding evidence-based vaccination strategies and monitoring programs for precise and effective outcomes.

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.

In vitro activity of clindamycin, doxycycline, and trimethoprim/sulfamethoxazole against clinical isolates of β-hemolytic Streptococcus spp. via BD Phoenix and broth microdilution

We tested 85 isolates of β-hemolytic Streptococcus spp. against trimethoprim/sulfamethoxazole (TMP/SMX), clindamycin, and doxycycline by broth microdilution (BMD) and BD Phoenix. Susceptibility rates via BMD for TMP/SMX, clindamycin, and doxycycline were 100%, 85.5%, and 56.6%, respectively. TMP/SMX is a potential monotherapy agent for β-hemolytic Streptococcus skin and soft tissue infections.

Prevalence of reported penicillin allergy and associations with perioperative complications, length of stay, and cost in patients undergoing elective cancer surgery

Objective

Up to 10% of patients report penicillin allergy (PA), although only 1% are truly affected by Ig-E-mediated allergies. PA has been associated with worse postoperative outcomes, but studies on the impact of reported PA in cancer patients are lacking, and especially in these multimorbid patients, a non-complicated course is of utmost importance.

Methods

Retrospective analysis of patients undergoing elective oncological surgery at a tertiary reference center. Data on surgical site infections (SSI), postoperative complications (measured by Clavien-Dindo classification and Comprehensive Complication Index (CCI)), hospitalization duration, and treatment costs were collected.

Results

Between 09/2019 and 03/2020, 152 patients were identified. 16/152 patients (11%) reported PA, while 136/152 (89%) did not. There were no differences in age, BMI, Charlson Comorbidity Index, and smoking status between groups (p > 0.4). Perioperative beta-lactam antibiotics were used in 122 (89.7%) and 15 (93.8%) patients without and with reported PA, respectively. SSI and mean numbers of infections occurred non-significantly more often in patients with PA (p = 0.2 and p = 0.47). The median CCI was significantly higher in PA group (26 vs. 51; p = 0.035). The median hospitalization duration and treatment costs were similar between non-PA and PA groups (4 vs 3 days, p = 0.8; 16'818 vs 17'444 CHF, p = 0.4).

Conclusions

In patients undergoing cancer surgery, reported PA is common. Failure to question the unproven PA may impair perioperative outcomes. For this reason, patient and provider education on which reactions constitute a true allergy would also assist in allergy de-labeling. In addition, skin testing and oral antibiotic challenges can be performed to identify the safe antibiotics and to de-label appropriate patients.

Using antibiotics wisely

PURPOSE OF REVIEW

This review will describe role of shorter antibiotic therapies, early switch from intravenous to oral therapy, and artificial intelligence in infectious diseases.

RECENT FINDINGS

There is evidence that shorter courses of antibiotics are noninferior to standard durations of therapy. This has been demonstrated with Enterobacterales bacteremia that can be treated with 7 days of therapy, community acquired pneumonia with 3 days and ventilator associated pneumonia with just 7 days of antibiotic therapy. The conversion from intravenous to oral therapy in treating bacteremia, endocarditis and bone and joint infections is safe and effective and reduces line complications and costs. Also, for clean surgical procedures only one dose of antibiotic is needed, but it should be the most effective antibiotic which is cefazolin. This means avoiding clindamycin, removing penicillin allergies where possible for improved outcomes. Finally, the role of artificial intelligence to incorporate into using antibiotics wisely is rapidly emerging but is still in early stages.

SUMMARY

In using antibiotics wisely, targeting such as durations of therapy and conversion from intravenous antibiotic therapy to oral are low hanging fruit. The future of artificial intelligence could automate a lot of this work and is exciting but needs to be proven.

VIDEO ABSTRACT

http://links.lww.com/COID/A50.

Describing Self-Reported Penicillin Allergy Using a Penicillin Allergy Risk Tool (PEN-FAST) in an Outpatient Setting at a Tertiary Hospital in Saudi Arabia

Introduction Penicillin is a widely used antibiotic and is frequently reported as a cause of allergic reactions. However, many individuals reporting penicillin allergies are later found to be tolerant. This study, conducted in an outpatient setting at King Abdulaziz University Hospital (KAUH) in Jeddah, Saudi Arabia, aimed to assess the prevalence of self-reported penicillin allergy and to evaluate further the risk of a positive penicillin allergy test using the PEN-FAST tool. Methods A cross-sectional study was conducted via in-person questionnaires with patients in the waiting area at the outpatient clinics of KAUH in Jeddah, Saudi Arabia. Results Among 140 participants, 4% reported a penicillin allergy, with most identifying their allergies based on symptoms. None of these allergies resulted in severe reactions. Notably, 50% reported nausea and itching as symptoms. The PEN-FAST tool categorized 33.3% as moderate risk and 50% as low to very low risk for a positive penicillin skin test. One participant was confirmed to be allergic via a skin prick test. Discussion and conclusion The prevalence of reported penicillin allergy was lower in our study than that previously reported. Evaluation of the PEN-FAST score demonstrated that this prevalence is even lower at 2%. While this single-center study offers valuable insights, further research in diverse healthcare settings is required to validate these findings and refine our understanding of penicillin allergies.

Penicillin Allergy Impact and Management

There is international evidence that penicillin allergies are associated with inferior prescribing and patient outcomes. A host of tools now exist from assessment (risk assessment tools, clinical decision rules) to delabeling (the removal of a beta-lactam allergy via testing or medical reconciliation) to reduce the impact of these "labels" in the hospital and community setting, as a primary antimicrobial stewardship intervention.

Challenges and opportunities related to penicillin allergy in the Veterans Health Administration: a narrative review

The presence of a penicillin allergy label in a patient's medical chart is associated with negative clinical and economic outcomes. Given that less than 10% of reported reactions are truly immunoglobulin E-mediated, removal of unverified penicillin allergy labels is a public health priority and an area of ongoing implementation research. The Veterans Health Administration (VHA) is the largest integrated healthcare system in the United States, with almost 9 million veterans currently enrolled. However, studies analyzing the impact of the penicillin allergy label in this population are limited to single facilities and largely focus on short-term outcomes of allergy documentation correction, usage of β-lactams, and avoidance of antibiotic-related side effects. Broader, national VHA studies focusing on health outcomes and costs are lacking. As with non-VHA facilities, penicillin allergy evaluations are limited owing to the absence of formal allergy/immunology services at most VHA facilities. Pharmacy-driven screening and referral for clinic-based penicillin skin testing is a promising and frequently discussed modality in the literature, but its scalability within the VHA is not yet proven. Broader, evidence-based strategies that can be adapted to the available resources of individual VHA facilities, including those without on-site access to allergy providers, are needed.

[Antibiotic allergies: targeted approach in suspected β‑lactam allergy]

Allergic reactions to antibiotics belong to hypersensitivity drug reactions and can trigger both immunoglobulin E-mediated symptoms and T cell-mediated symptoms. Skin manifestations are the most common symptoms. Although reporting a penicillin allergy results in considerable restrictions in the treatment of acute infections, which may be associated with poor treatment outcomes, in most cases the label 'penicillin allergy' is not called into question or critically reviewed. However, in 85-90% of patients, 'penicillin allergy' constitutes a mislabeling of a non-specific intolerance reaction that does not pose a risk to the patient when re-exposed to penicillins. Careful history taking, an evaluation of manifestations in the past, and easy-to-perform initial diagnostic steps are crucial in differentiating non-specific intolerance reactions from penicillin allergy sensu stricto. Thus, a penicillin de-labeling strategy allows for optimized antibiotic therapy in the event of a future infection. Although allergic cross-reactivity between different β‑lactam antibiotics can occur, the risk for a severe cross-reactivity is dependent on chemical properties of the specific β‑lactam. Published cross-reactivity tables can help in risk stratification and choice of alternative β‑lactam agents.

Should Penicillin Allergy Testing Be Included as Part of Preoperative Testing?

INTRODUCTION

Penicillin allergy is the most commonly reported drug allergy in the United States. Patients labeled with penicillin allergy are at risk of receiving broad-spectrum antibiotics for surgical site infection prophylaxis, which can lead to increased antibiotic resistance, higher morbidity, suboptimal antibiotic therapy, and higher medical costs. This study aimed to determine the true prevalence of penicillin allergy among surgical patients and to decrease the unnecessary use of broad-spectrum antibiotics.

METHODS

A retrospective chart review was performed of patients who underwent urogynecologic surgery in 2017. In 2018, a quality initiative was started, and all patients reporting penicillin allergies were offered antibiotic allergy testing as part of their preoperative testing.

RESULTS

In 2017, 15% of patients reported penicillin allergy and 52% of them received surgical prophylaxis with broad-spectrum antibiotics. In 2018, 463 patients underwent surgery, 55 of whom reported penicillin allergy and were offered penicillin allergy testing. 35 (64%) agreed to proceed with testing, and of those tested, 33 (94%) tested negative for penicillin allergy.

CONCLUSIONS

94% of patients with stated penicillin allergy who consented to allergy testing proved to have negative test. Penicillin allergy testing should be considered as part of preoperative management.