Prophylactic Antibiotic Management of Surgical Patients Noted as “Allergic” to Penicillin at Two Academic Hospitals

Pharmacology of spinal interventions: review of agents used in spine pain procedures

Spine procedures are commonly performed to diagnose and treat various spinal conditions, ranging from degenerative disc disease to vertebral fractures. These procedures often involve the use of pharmaceutical agents to enhance the efficacy of the intervention and improve patient outcomes. This review provides an overview of the pharmaceuticals commonly utilized in spine procedures, including corticosteroids, anesthetics, antibiotics, radiographic contrast, neurolytic agents, and materials used in kyphoplasty and vertebroplasty. This review summarizes the utilization of these pharmaceutical agents in spine procedures in an effort to optimize patient outcomes. Understanding the pharmacological properties and appropriate uses of these pharmaceuticals is essential for interventionalist and healthcare providers involved in the care of patients undergoing spinal interventions.

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.

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.

Classifying cephalosporins: from generation to cross-reactivity

PURPOSE OF REVIEW

To review the most recent literature studying the classifications, immunochemistry, and crossreactivity of allergy reactions to cephalosporins.

RECENT FINDINGS

Over the last five years, research interest has focused on three areas related to cephalosporin allergy: cross-reactivity among cephalosporins and with other beta-lactams; the incidence of adverse reactions in penicillin allergy patients or in reported penicillin allergy labels; and new cephalosporins structures involved in the immunological recognition.

SUMMARY

Meta-analysis of a substantial number of studies shows that cephalosporins are safer than previously thought. Evidence supports two main conclusions in that regard. First, there is a relatively low percentage of cross-reactivity between cephalosporins and other beta-lactams with penicillins in penicillin allergy patients. Second, there is a very low incidence of allergy reactions in nonselected as well as in selected penicillin allergy patients when cephalosporins are used prior to surgical intervention.On the other hand, few structures have been discovered related to the immune mechanism of cephalosporin allergy reactions, and these are far from being ready to use in clinical practice.

Antibiotic allergy labels and optimal antimicrobial stewardship

BACKGROUND

Although common, antimicrobial allergy labels (AAL) rarely reflect immunologically-mediated hypersensitivity and can lead to poorer outcomes from alternative antimicrobial agents. Antimicrobial stewardship programs are ideally placed to assess AAL early as a means of improving antimicrobial use.

OBJECTIVES

To quantify the prevalence of AAL in patients referred for antimicrobial stewardship review and assess their impact on antibiotic prescribing, patient mortality, hospital length of stay, readmission, and rates of multidrug-resistant infections.

METHODS

We conducted a retrospective analysis of adult patients referred for inpatient antimicrobial prospective audit and feedback rounds (PAFR) via an electronic referral system (eReferrals) over a 12-month period in 2015. Outcome data was collected for a period of 36 months following the initial review.

RESULTS

Of the 639 patient records reviewed, 630 met inclusion criteria; 103 (16%) had an AAL, of which 82 (13%) had reported allergies to β-lactam antibiotics. Those with AAL were significantly less likely to be receiving guideline-recommended antimicrobial therapy (50% versus 64%, p=0.0311), however there were no significant difference in mortality, hospital length of stay, readmission or increased incidence of multidrug-resistant infections.

CONCLUSIONS

Our cohort demonstrated that AAL was associated with reduced adherence to antibiotic guidelines. The lack of association with adverse outcomes may reflect limitations within the study including retrospective cohort study numbers and observational nature, further skewed by high rates of poor documentation. A clear opportunity exists for antimicrobial stewardship programs to incorporate allergy assessment, delabelling, challenge and referral into these rounds. This article is protected by copyright. All rights reserved.

The association of penicillin allergy with outcomes after open ventral hernia repair

BACKGROUND

Up to 11% of patients report a penicillin allergy (PA), with 1-2% demonstrating a true IgE mediated allergy upon testing. PA patients often receive non-beta-lactam antibiotic surgical prophylaxis (non-BLP). This study evaluates the relationship of PA to outcomes after open ventral hernia repair (OVHR).

METHODS

A prospective institutional database was queried for patients undergoing OVHR. Demographics, operative characteristics, and outcomes were evaluated by the reported PA and the administration of beta-lactam prophylaxis (BLP).

RESULTS

Allergy histories were reviewed in 1178 patients. PA was reported in 21.6% of patients, with 55.5% reporting rash or hives, 15.0% airway compromise or anaphylaxis, and 29.5% no specific reaction. BLP was administered to 76.3% of patients, including 22.1% of PA patients and 89.9% of patients without PA. PA patients were more often female (64.6% PA patients vs. 56% non-PA, p = 0.01), with higher rates of chronic steroids, MRSA, anxiety, asthma, COPD, chronic pain, and sleep apnea (p < 0.03 all values). PA patients had higher rates of contaminated cases, including mesh infection and fistula. Of the 683 clean cases, 82.1% received BLP. Of the 117 clean contaminated cases (CDC wound class 2), 82.9% received BLP, which was associated with reduced long-term readmission for hernia complications (21.5 vs. 55%, p = 0.002, OR 0.27, CI 0.09-0.83). In the 120 CDC wound class 3 and 4 patients, 65.8% received BLP. In multivariate analysis, BLP was associated with lower rates of reoperation (OR 0.31, CI 0.12-0.76) and recurrence (OR 0.32, CI 0.11-0.86). BLP was given to 22.1% of the PA patients with no adverse reactions noted.

CONCLUSION

PA patients had more comorbidities and complex ventral hernias. When controlling for contamination and MRSA history, BLP is associated with improved outcomes particularly in contaminated cases. PA may be a risk factor for patient complexity, and further studies are warranted to determine if allergy testing can be warranted in known or anticipated contaminated cases.

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

Background

A reported penicillin allergy may compromise receipt of recommended antibiotic prophylaxis intended to prevent surgical site infections (SSIs). Most patients with a reported penicillin allergy are not allergic. We determined the impact of a reported penicillin allergy on the development of SSIs.

Methods

In this retrospective cohort study of Massachusetts General Hospital hip arthroplasty, knee arthroplasty, hysterectomy, colon surgery, and coronary artery bypass grafting patients from 2010 to 2014, we compared patients with and without a reported penicillin allergy. The primary outcome was an SSI, as defined by the Centers for Disease Control and Prevention's National Healthcare Safety Network. The secondary outcome was perioperative antibiotic use.

Results

Of 8385 patients who underwent 9004 procedures, 922 (11%) reported a penicillin allergy, and 241 (2.7%) had an SSI. In multivariable logistic regression, patients reporting a penicillin allergy had increased odds (adjusted odds ratio, 1.51; 95% confidence interval, 1.02-2.22) of SSI. Penicillin allergy reporters were administered less cefazolin (12% vs 92%; P < .001) and more clindamycin (49% vs 3%; P < .001), vancomycin (35% vs 3%; P < .001), and gentamicin (24% vs 3%; P < .001) compared with those without a reported penicillin allergy. The increased SSI risk was entirely mediated by the patients' receipt of an alternative perioperative antibiotic; between 112 and 124 patients with reported penicillin allergy would need allergy evaluation to prevent 1 SSI.

Conclusions

Patients with a reported penicillin allergy had a 50% increased odds of SSI, attributable to the receipt of second-line perioperative antibiotics. Clarification of penicillin allergies as part of routine preoperative care may decrease SSI risk.

Cephalosporins: A Focus on Side Chains and β-Lactam Cross-Reactivity

Cephalosporins are among the most commonly prescribed antibiotic classes due to their wide clinical utility and general tolerability, with approximately 1-3% of the population reporting a cephalosporin allergy. However, clinicians may avoid the use of cephalosporins in patients with reported penicillin allergies despite the low potential for cross-reactivity. The misdiagnosis of β-lactam allergies and misunderstanding of cross-reactivity among β-lactams, including within the cephalosporin class, often leads to use of broader spectrum antibiotics with poor safety and efficacy profiles and represents a serious obstacle for antimicrobial stewardship. Risk factors for cephalosporin allergies are broad and include female sex, advanced age, and a history of another antibiotic or penicillin allergy; however, cephalosporins are readily tolerated even among individuals with true immediate-type allergies to penicillins. Cephalosporin cross-reactivity potential is related to the structural R1 side chain, and clinicians should be cognizant of R1 side chain similarities when prescribing alternate β-lactams in allergic individuals or when new cephalosporins are brought to market. Clinicians should consider the low likelihood of true cephalosporin allergy when clinically indicated. The purpose of this review is to provide an overview of the role of cephalosporins in clinical practice, and to highlight the incidence of, risk factors for, and cross-reactivity of cephalosporins with other antibiotics.

Optimizing preoperative prophylaxis in patients with reported β-lactam allergy: a novel extension of antimicrobial stewardship

Background

Use of alternative second-line antibiotics is associated with adverse events in patients reporting β-lactam allergy. In the perioperative setting, we hypothesized that structured allergy histories, without the use of skin testing, can reduce alternative prophylactic antibiotic use.

Objectives

Assess the impact of structured allergy histories on patients with self-reported β-lactam allergy (SRBA) undergoing elective surgical procedures.

Methods

Structured allergy histories were performed by a pharmacist and reviewed with an infectious diseases physician. Patients were deemed safe to proceed with cefazolin prophylaxis if they did not describe a history of type I-mediated or severe reaction. Antibiotic prophylaxis orders (with approval by the surgical team) were scheduled into the computerized order entry system to be given prior to first incision of the operation.

Results

Of the 485 patients with SRBA that underwent structured allergy histories, 117 (24.1%) reported a type I-mediated allergy history; 267 (55.1%) patients received cefazolin prophylaxis and none subsequently experienced an adverse reaction. After intervention implementation, the overall use of alternative antibiotic prophylaxis at Michael Garron Hospital (Toronto, Canada) among those with SRBA decreased from 81.9% to 55.9%. This drop was associated with the number of monthly assessments (P < 0.001) in a regression analysis.

Conclusions

Using a simple structured history and the principles of prospective audit and feedback, we were able to increase the use of cefazolin perioperative prophylaxis without any serious adverse events and in the absence of skin testing or diagnostic challenges.