Evaluation and Management of Penicillin Allergy: A Review

Differences in oxazolidinone resistance mechanisms and small colony variants emergence of Staphylococcus aureus induced in an in vitro resistance development model

Invasive Staphylococcus aureus infections are associated with a high burden of disease, case fatality rate and healthcare costs. Oxazolidinones such as linezolid and tedizolid are considered potential treatment choices for conditions involving methicillin resistance or penicillin allergies. Additionally, they are being investigated as potential inhibitors of toxins in toxin-mediated diseases. In this study, linezolid and tedizolid were evaluated in an in vitro resistance development model for induction of resistance in S. aureus. Whole genome sequencing was conducted to elucidate resistance mechanisms through the identification of causal mutations. After inducing resistance to both linezolid and tedizolid, several partially novel single nucleotide variants (SNVs) were detected in the rplC gene, which encodes the 50S ribosome protein L3 in S. aureus. These SNVs were found to decrease the binding affinity, potentially serving as the underlying cause for oxazolidinone resistance. Furthermore, in opposite to linezolid we were able to induce phenotypically small colony variants of S. aureus after induction of resistance with tedizolid for the first time in literature. In summary, even if different antibiotic concentrations were required and SNVs were detected, the principal capacity of S. aureus to develop resistance to oxazolidinones seems to differ between linezolid and tedizolid in-vivo but not in vitro. Stepwise induction of resistance seems to be a time and cost-effective tool for assessing resistance evolution. Inducted-resistant strains should be examined and documented for epidemiological reasons, if MICs start to rise or oxazolidinone-resistant S. aureus outbreaks become more frequent.

Advances in Bowel Preparation and Antimicrobial Prophylaxis for Open and Laparoscopic Urologic Surgery

Surgical site infections (SSIs) represent a major source of postoperative complications adversely impacting morbidity and mortality indices in surgical care. The discovery of antibiotics in the mid-20th century, and their ensuing use for preoperative antimicrobial bowel preparation and prophylaxis, drastically reduced the occurrence of SSIs providing a major tool to surgeons of various specialties, including urology. Because, the appropriate use of these antimicrobials is critical for their continued safety and efficacy, an understanding of the recommendations guiding their application is essential for all surgeons. Here, we comprehensively review these recommendations with a focus on open and laparoscopic urologic surgeries.

Novel ratiometric electrochemical aptasensor based on broad-spectrum aptamer recognition for simultaneous detection of penicillin antibiotics in milk

To effectively monitor multi-residues of penicillin antibiotics (PENs) in milk, we developed a novel ratiometric electrochemical aptasensor enabling simultaneous detection of PENs. The aptasensor employed a broad-spectrum aptamer as a recognition element, niobium carbide functionalized with methylene blue (Nb2C-MB) as a reference signal generator, and a ferrocene-labeled aptamer (Fc-Apt) as an output signal. Electrodes were modified with Fe-N-C doped carbon nanotubes (Fe-N-C-CNTs) to amplify detection signals further. During detection, Fc-Apt binding to PENs decreased Fc current intensity (IFc) and increased MB current intensity (IMB). The simultaneous detection of PENs was achieved using IMB/IFc as a quantitative signal. Under optimal conditions, a good linear relationship between IMB/IFc and antibiotic concentration was observed, indicating the aptasensor had a robustness. The limits of detection of aptasensor for four penicillin antibiotics and their mixed targets were 0.093-0.191 nM. This work provides a new approach to multi-residue detection of the same class of antibiotics.

Clinical Relevance of Specific IgE in Penicillin Allergy Investigation

INTRODUCTION

Patients with immediate type allergic reactions to penicillins are at risk of anaphylaxis on reexposure. Diagnostic gold standard is drug provocation test (DPT) if allergy is not diagnosed by other means, such as skin testing or in vitro testing with measurement of specific IgE. Specific IgE testing carries low risk for the patient and blood sampling can be performed in primary care, but it is reported to have low sensitivity. The aim of this study was to evaluate if clinical characteristics of patients with suspected allergic reactions to penicillin and elevated specific IgE to penicillins, differed from patients without specific IgE, to identify predictors for elevated specific IgE to penicillins.

METHODS

Levels of specific IgE to five penicillins (penicillin G, penicillin V, amoxicillin, ampicillin, and penicillin minor determinants) were available for 9,100 patients. Using multiple logistic regression, clinical data from 430 patients in this group who had elevated specific IgE to one or more penicillins were compared to data from 4,094 patients without specific IgE to penicillins, who had undergone DPT with a penicillin.

RESULTS

In total 5.2% of patients had elevated specific IgE to one or more penicillins. Significantly more patients with elevated specific IgE had a history of immediate type reactions (<2 h) (OR = 4.34, p < 0.001); circulatory symptoms (OR = 1.63, p = 0.03) or angioedema (OR = 1.46, p = 0.005). Also, significantly more patients with elevated specific IgE had been treated with adrenaline (OR = 2.21, p = 0.005), steroids (OR = 1.76, p < 0.001), or antihistamines (OR = 1.83, p < 0.001).

CONCLUSION

A history of an immediate type reaction requiring treatment, combined with elevated specific IgE to one or more penicillins is suggestive of an IgE mediated penicillin allergy and further allergy investigations may not be needed. Specific IgE to penicillins may be used early in allergy investigation of patients with severe immediate type reactions to penicillins.

Reliability and validation of an electronic penicillin allergy risk-assessment tool in a pregnant population

BACKGROUND

Penicillin allergy adversely impacts patient care, yet most cases do not have true allergies. Clinicians require efficient, reliable clinical tools to identify low risk patients who can be safely de-labeled. Our center implemented the FIRSTLINE electronic point-of-care decision support tool to help non-allergist practitioners risk stratify patients with penicillin allergy. We sought to explore the reliability and validity of this tool in relation to allergist assessment and actual patient outcomes. We additionally compared it with two other published stratification tools, JAMA and PENFAST, to assess ability to accurately identify low risk patients appropriate for direct oral challenge.

METHODS

In this single-center, retrospective, observational study, 181 pregnant females with self-reported penicillin allergy between July 2019 to June 2021 at BC Women's Hospital, Vancouver, Canada were used to assess the reliability and validity of all three tools. Physician-guided history of penicillin use and symptoms were used for scoring. Results and recommendations were compared to actual patient outcomes after clinician decision for direct oral challenge or intradermal tests. We compared the performance of JAMA, PENFAST and FIRSTLINE.

RESULTS

181 patients were assessed. 176/181 (97.2%) patients were deemed not allergic. Each risk stratification tool labelled majority of patients as low risk with 88.4% of patients PENFAST 0-2, 60.2% of patients JAMA low risk, 86.7% of patients FIRSTLINE very low risk.

CONCLUSION

We demonstrate that our point-of-care electronic algorithm is reliable in identifying low risk pregnant patients, as compared to an allergist assessment. To our knowledge, this is the first study to provide direct comparison between multiple decision support tools using the same population, minimizing participant bias. Providing clinical algorithms to risk stratify patients, can enable healthcare professionals to safely identify individuals who may be candidates for direct penicillin oral challenges versus needing referral to specialists. This increases the generalizability and efficiency of penicillin allergy de-labeling.

Community-Acquired Pneumonia: A Review

Importance

Community-acquired pneumonia (CAP) results in approximately 1.4 million emergency department visits, 740 000 hospitalizations, and 41 000 deaths in the US annually.

Observations

Community-acquired pneumonia can be diagnosed in a patient with 2 or more signs (eg, temperature >38 °C or ≤36 °C; leukocyte count <4000/μL or >10 000/μL) or symptoms (eg, new or increased cough or dyspnea) of pneumonia in conjunction with consistent radiographic findings (eg, air space density) without an alternative explanation. Up to 10% of patients with CAP are hospitalized; of those, up to 1 in 5 require intensive care. Older adults (≥65 years) and those with underlying lung disease, smoking, or immune suppression are at highest risk for CAP and complications of CAP, including sepsis, acute respiratory distress syndrome, and death. Only 38% of patients hospitalized with CAP have a pathogen identified. Of those patients, up to 40% have viruses identified as the likely cause of CAP, with Streptococcus pneumoniae identified in approximately 15% of patients with an identified etiology of the pneumonia. All patients with CAP should be tested for COVID-19 and influenza when these viruses are common in the community because their diagnosis may affect treatment (eg, antiviral therapy) and infection prevention strategies. If test results for influenza and COVID-19 are negative or when the pathogens are not likely etiologies, patients can be treated empirically to cover the most likely bacterial pathogens. When selecting empirical antibacterial therapy, clinicians should consider disease severity and evaluate the likelihood of a bacterial infection-or resistant infection-and risk of harm from overuse of antibacterial drugs. Hospitalized patients without risk factors for resistant bacteria can be treated with β-lactam/macrolide combination therapy, such as ceftriaxone combined with azithromycin, for a minimum of 3 days. Systemic corticosteroid administration within 24 hours of development of severe CAP may reduce 28-day mortality.

Conclusions

Community-acquired pneumonia is common and may result in sepsis, acute respiratory distress syndrome, or death. First-line therapy varies by disease severity and etiology. Hospitalized patients with suspected bacterial CAP and without risk factors for resistant bacteria can be treated with β-lactam/macrolide combination therapy, such as ceftriaxone combined with azithromycin, for a minimum of 3 days.

Preventing Overrides of Severe Drug Allergy Alerts Initiative: an Implemented System Upgrade

Administering medications to patients with documented drug hypersensitivity reactions (DHR) poses a significant risk for adverse events, ranging from mild reactions to life-threatening incidents. Electronic healthcare systems have revolutionized the modern clinical decision-making process, with built in warnings. However, as these alerts become a routine part of healthcare provider's workflow, alert fatigue becomes a challenge. This study was conducted within the Ministry of National Guard Health Affairs (MNGHA), a government healthcare system in Saudi Arabia. A taskforce of experts was formed to develop an electronic path that would prevent unintentional overrides of severe drug allergy alerts. The system underwent rigorous testing, and monitoring parameters were established. We outline the implementation of a system upgrade designed to trigger an alternative interruption in the computerized physician order entry (CPOE) process, distinct from the regular allergy pop-up alerts. The alternate path is activated upon a CPOE with a drug-to-drug match and a documented severe drug allergy symptom, necessitating co-signature form another prescriber before proceeding. The adopted upgrade is a proactive approach to enhance medication safety in electronic healthcare systems, ensuring that serious allergy-related warnings are not overridden, ultimately enhancing patient safety. Further monitoring will confirm the safety and effectiveness of this measure. This study provides a model for institutions seeking to prevent allergy-related harm within their patient population.

Documented penicillin allergy and beta-lactam antibiotic use in Massachusetts long-term care facilities: opportunities for penicillin allergy delabeling

In a cross-sectional study of 20 Massachusetts long-term care (LTC) facilities, 19% (n = 449) of residents received antibiotics, with approximately one-third having a documented penicillin allergy. This documented allergy decreased the likelihood of prescribing beta-lactam antibiotics for infections. Improved penicillin allergy assessments and delabeling could optimize antibiotic prescribing in LTC settings.

Rising trend of dentist-prescribed antibiotics in Brazil: 2011-2021

OBJECTIVES

To describe the trends in antibiotic prescribing by dental practitioners and to investigate the relationship between these trends and some factors of public oral health services in Minas Gerais (MG), Brazil.

METHODS

This was a time-series analysis of antibiotics prescribed by dental practitioners between January 2011 and December 2021. The outcome variables were number of defined daily doses (DDD) and DDD/1000 population/year in a sample of cities in MG. Covariates were public oral healthcare factors, such as coverage, estimates of dental procedures, and frequency of dental pain. Linear time-series regression models were used to examine trends and the influence of covariates on antibiotic prescribing.

RESULTS

Overall, the number of prescriptions increased by 334.69% between 2011 and 2021, with amoxicillin being the most commonly prescribed drug (78.53%). The number of DDD for all antibiotics increased from 17,147.13 to 77,346.67 and the average DDD/1000 inhabitants/year was 126.66 (SD: 130.28). The linear time-series regression model showed that for each one-year increase, the average log DDD/1000 inhabitants increased by 0.35 (standard error = 0.07, p < 0.001). No covariates were found to be associated with the outcome.

CONCLUSIONS

In Minas Gerais, Brazil, a significant upward trend was observed in the number of prescriptions and the number of DDD of antibiotics prescribed by dental practitioners. No influence of factors related to public oral healthcare services on the outcome was observed, thereby emphasizing the need for further research on factors influencing medication use in dental practice.

Utilising primary care electronic health records to deliver the ALABAMA randomised controlled trial of penicillin allergy assessment

BACKGROUND

Use of electronic health records (EHR) to provide real-world data for research is established, but using EHR to deliver randomised controlled trials (RCTs) more efficiently is less developed. The Allergy AntiBiotics And Microbial resistAnce (ALABAMA) RCT evaluated a penicillin allergy assessment pathway versus usual clinical care in a UK primary care setting. The aim of this paper is to describe how EHRs were used to facilitate efficient delivery of a large-scale randomised trial of a complex intervention embracing efficient participant identification, supporting minimising GP workload, providing accurate post-intervention EHR updates of allergy status, and facilitating participant follow up and outcome data collection. The generalisability of the EHR approach and health economic implications of EHR in clinical trials will be reported in the main ALABAMA trial cost-effectiveness analysis.

METHODS

A descriptive account of the adaptation of functionality within SystmOne used to deliver/facilitate multiple trial processes from participant identification to outcome data collection.

RESULTS

An ALABAMA organisation group within SystmOne was established which allowed sharing of trial functions/materials developed centrally by the research team. The 'ALABAMA unit' within SystmOne was also created and provided a secure efficient environment to access participants' EHR data. Processes of referring consented participants, allocating them to a trial arm, and assigning specific functions to the intervention arm were developed by adapting tools such as templates, reports, and protocols which were already available in SystmOne as well as pathways to facilitate allergy de-labelling processes and data retrieval for trial outcome analysis.

CONCLUSIONS

ALABAMA is one of the first RCTs to utilise SystmOne EHR functionality and data across the RCT delivery, demonstrating feasibility and applicability to other primary care RCTs.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT04108637, registered 05/03/2019. ISRCTN: ISRCTN20579216.

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.

Delabeling of allergy to beta-lactam antibiotics in hospitalized patients: a prospective study evaluating cost savings

BACKGROUND

Patients with a penicillin allergy label are at risk of an associated increase in adverse antibiotic events and hospitalization costs.

AIM

We aimed to study the economic savings derived from the correct diagnosis and delabeling inpatients with suspected beta-lactam allergy, considering the acquisition cost of antimicrobials prescribed during a patient's hospital stay.

METHOD

We prospectively evaluated patients admitted to the University Hospital of Salamanca who had been labeled as allergic to beta-lactams and performed a delabeling study. Subsequently, cost differences between antibiotics administered before and after the allergy study and those derived from those patients who received alternative antibiotics during admission and those who switched to beta-lactams after the allergy study were calculated.

RESULTS

One hundred seventy-seven inpatients labeled as allergic to beta-lactams underwent a delabeling study; 34 (19.2%) were confirmed to have allergy to beta-lactams. Of the total number of patients, 136 (76.8%) received antibiotics during their hospitalization, involving a mean (SD) cost of €203.07 (318.42) and a median (IQR) cost of €88.97 (48.86-233.56). After delabeling in 85 (62.5%) patients, the antibiotic treatment was changed to beta-lactams. In this group of patients, the mean cost (SD) decreased from €188.91 (351.09) before the change to 91.31 (136.07) afterward, and the median cost (IQR) decreased from €72.92 (45.82-211.99) to €19.24 (11.66-168). The reduction was significant compared to the median cost of patients whose treatment was not changed to beta-lactams (p<0.001).

CONCLUSION

Delabeling hospitalized patients represents a cost-saving measure for treating patients labeled as allergic to beta-lactams.

Guidelines to practice in hospitals at home: safe and effective continuous infusion pumps substantially increased penicillin use in erysipelas treatment

Hospitals at home are increasingly offering outpatient parenteral antimicrobial therapy (OPAT) in an attempt to reduce costly inpatient care, but these settings favour broad-spectrum antibiotics that require less frequent dosing than penicillin. Benzyl penicillin could be delivered via continuous infusion pumps (eCIPs), but studies on their safety and efficacy in OPAT are scarce, and it remains unclear how much the availability of eCIPs increases penicillin use in real-life settings. We examined 462 electronic healthcare records of erysipelas patients treated between January 2018 and January 2022 in a large Finnish OPAT clinic. Average marginal effects from logistic models were estimated to assess how the introduction of eCIPs in December 2020 affected penicillin use and to compare clinical outcomes between patients with and without eCIPs. Introduction of eCIPs increased the predicted probability of penicillin treatment by 36.0 percentage points (95% confidence interval 25.5-46.5). During eCIP implementation, patients who received an eCIP had 73.1 (58.0-88.2) percentage points higher probability than patients without an eCIP to receive penicillin treatment. They also had about 20 percentage points higher probability to be cured at the time of discharge and 3 months after it. Patient and nurse satisfaction regarding eCIPs was very high. Benzyl penicillin eCIP treatment is effective and safe, and substantially increases the use of penicillin instead of broad-spectrum antibiotics. To reduce the risk of antimicrobial resistance, eCIPs could increasingly be promoted for use in OPAT clinics, and there should be adequate education and support in their implementation.

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.

Empowering Pediatricians With Direct Penicillin Challenges: A Promising Delabeling Strategy

OBJECTIVE

Current literature supports a multidisciplinary approach to penicillin allergy delabeling. Our study aims to review the success rate of penicillin challenges performed at Walter Reed National Military Medical Center Allergy Clinic and assess the reaction rate associated with a direct oral challenge in low-risk patients.

MATERIALS AND METHODS

We conducted a retrospective review of the outcomes of pediatric penicillin challenges at the Walter Reed National Military Medical Center Allergy and Immunology clinic from June 2019 to May 2023. A total of 74 challenges were included in this study. Patients were initially screened to assess the date of reaction, nature of reaction, if the reaction was life-threatening, and if the patient was hospitalized or sought emergency medical care for the reported reaction. After completion of the screening questionnaire, a direct graded challenge was performed (without skin testing) if a patient's history was deemed low risk. Patients with a recent reaction or a history of multiple drug allergies were more likely to be directed to skin prick testing and intra-dermal testing with Pre-pen and Penicillin-G prior to challenge.

RESULTS

All patients passed all challenges. Thus, there was a 100% pass rate for both direct challenges and skin test with oral challenges.

CONCLUSION

Given the low rate of adverse events in this study, expansion of penicillin delabeling in the primary care setting should be considered in patients deemed to be at low risk. It is important for allergists to empower and educate their peers and push forward a movement to create a multidisciplinary approach to penicillin delabeling.

Experts consensus on management of tooth luxation and avulsion

Traumatic dental injuries (TDIs) of teeth occur frequently in children and adolescents. TDIs that impact the periodontal tissues and alveolar tissue can be classified into concussion, subluxation, extrusive luxation, intrusive luxation, lateral luxation, and avulsion. In these TDIs, management of injured soft tissue, mainly periodontal ligament, and dental pulp, is crucial in maintaining the function and longevity of the injured teeth. Factors that need to be considered for management in laxation injuries include the maturation stage of the traumatic teeth, mobility, direction of displacement, distance of displacement, and whether there are alveolar fractures. In avulsion, the maturation stage of the permanent tooth, the out-socket time, storage media/condition of the avulsed tooth, and management of the PDL should also be considered. Especially, in this review, we have subdivided the immature tooth into the adolescent tooth (Nolla stage 9) and the very young tooth (Nolla stage 8 and below). This consensus paper aimed to discuss the impacts of those factors on the trauma management and prognosis of TDI to provide a streamlined guide for clinicians from clinical evaluation, diagnostic process, management plan decision, follow-up, and orthodontic treatment for tooth luxation and avulsion injuries.

Syphilis and pregnancy

•Although congenital syphilis has a known etiological agent, accessible diagnosis and low-cost, effective treatment with low fetal toxicity, it continues to challenge obstetric and antenatal care services. •The increasing rates of syphilis in the general population have direct repercussions on the increase in cases of congenital syphilis, a situation of objective interest for public health. •Although transforming the recording of syphilis and congenital syphilis into notifiable diseases improved the records and has made it possible to measure the occurrence of these diseases and create solutions, no effects on reducing their frequency have been reached yet. •The failure to control syphilis/congenital syphilis is multifactorial, and associates variables that range from the deficiency in teaching about these diseases in schools and in the training system of the various health professional segments, as well as the lack of rigid policies for quality control from antenatal care until the clinical follow-up of children exposed to Treponema pallidum during pregnancy. •To date, benzathine penicillin is the only antimicrobial accepted as effective by the main health authorities on the planet for the treatment of syphilis in pregnant women. •The fear of anaphylaxis in response to the treatment of syphilis with benzathine penicillin is an important factor hindering the prompt and correct treatment of pregnant women with syphilis, even though health authorities have made efforts to face the problem with solid arguments, still insufficient to resolve the question. •Although specific protocols are published, the failure to control the treatment of syphilis in pregnant women is still observed with high frequency, indicating and reinforcing a failure in the quality control of these care principles. The National Specialized Commission on Infectious Diseases of the Brazilian Federation of Gynecology and Obstetrics Associations (Febrasgo) endorses this document. Content production is based on scientific evidence on the proposed topic and the results presented contribute to clinical practice.

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.

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.

Patient Perceptions of Penicillin Allergy Testing in a Public Health System

BACKGROUND

Documented penicillin allergies are associated with increased morbidity, increased hospital stay, and an increase in resistant infections. Penicillin allergy evaluations using a direct oral challenge with or without skin testing has been recommended as a delabeling strategy for patients with penicillin reaction histories. Barriers for achieving equitable access, however, exist. Understanding patient perceptions regarding their penicillin allergy across diverse populations is crucial to mitigate potential obstacles to penicillin allergy testing (PAT) and the use of penicillin-like antibiotics after delabeling.

OBJECTIVE

The objective of this study was to gather perceptions of patients delabeled of their penicillin allergy after testing through a PAT program.

METHODS

Patients who underwent PAT and had a subsequent allergy removal due to a negative result were interviewed using closed and open-ended questions.

RESULTS

A total of 100 patient interviews were completed. Awareness of the risks associated with unnecessary penicillin avoidance and PAT was low. Initial concerns regarding PAT were common but were frequently alleviated with targeted education. Most patients undergoing testing reported a positive experience and would recommend PAT to others. A minority of patients continued to have discordant perceptions regarding their penicillin allergy label with mistrust in the negative result being a critical theme identified.

CONCLUSIONS

Future interventions increasing the awareness of penicillin allergy labels and the risks and benefits of PAT in the general population are needed and must consider health literacy levels, languages, and cultural contexts. Measures to offer PAT within a clinical setting that has built high levels of patient trust will likely achieve the greatest long-term success.

Molecular Targets in Streptococcus pyogenes for the Development of Anti-Virulence Agents

Streptococcus pyogenes, commonly known as Group A Streptococcus (GAS), is a significant human pathogen responsible for a wide range of diseases, from mild pharyngitis to severe conditions such as necrotizing fasciitis and toxic shock syndrome. The increasing antibiotic resistance, especially against macrolide antibiotics, poses a challenge to the effective treatment of these infections. This paper reviews the current state and mechanisms of antibiotic resistance in S. pyogenes. Furthermore, molecular targets for developing anti-virulence agents, which aim to attenuate virulence rather than killing it outright, are explored. This review specifically focuses on virulence regulators, proteins that coordinate the expression of multiple virulence factors in response to environmental signals, playing a crucial role in the pathogen's ability to cause disease. Key regulatory systems, such as RopB, Mga, CovRS, and the c-di-AMP signaling system, are discussed for their roles in modulating virulence gene expression. Additionally, potential molecular target sites for the development of anti-virulence agents are suggested. By concentrating on these regulatory pathways, it is proposed that anti-virulence strategies could enhance the effectiveness of existing antibiotics and reduce the selective pressure that drives the development of resistance.

DxGoals: A Software Tool for Determining and Analyzing Clinically Meaningful Classification Accuracy Goals for Diagnostic Tests

BACKGROUND

To evaluate diagnostic tests for low prevalence conditions, classification accuracy metrics such as sensitivity, specificity, and positive likelihood ratio (PLR) and negative likelihood ratio (NLR) are advantageous because they are prevalence-independent and thus estimable in studies enriched for the condition. However, classification accuracy goals are often chosen without a clear understanding of whether they are clinically meaningful. Pennello (2021) proposed a risk stratification framework for determining classification accuracy goals. A software application is needed to determine the goals and provide data analysis.

METHODS

We introduce DxGoals, a freely available, R-Shiny software application for determining, visualizing, and analyzing classification accuracy goals for diagnostic tests. Given prevalence p for the target condition and specification that a test's positive and negative predictive values PPVand NPV=1-cNPV should satisfy PPV>PPV* and cNPV

RESULTS

We illustrate DxGoals on tests for penicillin allergy, ovarian cancer, and cervical cancer. The inputs cNPV*,p, and PPV* were informed by clinical management guidelines.

CONCLUSIONS

DxGoals facilitates determination, visualization, and analysis of clinically meaningful standalone and comparative classification accuracy goals. It is a potentially useful tool for diagnostic test evaluation.

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Key Words Collapse

MESH Headings

• Humans
• Software
• Sensitivity and Specificity
• Bayes Theorem
• Diagnostic Tests, Routine/standards
• Diagnostic Tests, Routine/methods
• Predictive Value of Tests

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Affiliation(s)

Ngoc-Ty Nguyen U.S. Food and Drug Administration, Center for Biologics Evaluation and Research, Silver Spring, MD, United States
Gene A Pennello U.S. Food and Drug Administration, Center for Devices and Radiological Health, Silver Spring, MD, United States

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Group B Streptococcus and Intraamniotic Inflammation and Infection

Intraamniotic inflammation and infection complicate 2% to 5% of term deliveries. Group B Streptococcus (GBS) is a common cause of intraamniotic infection associated with invasive neonatal disease and maternal morbidity. Universal vaginal-rectal screening for GBS colonization is recommended between 36 and 37 weeks. Intrapartum antibiotic prophylaxis is recommended for individuals with positive GBS screens and other risk factors. Intravenous penicillin is the preferred antimicrobial agent. Individuals with penicillin allergies may receive cefazolin for low-risk allergies and either clindamycin or vancomycin for high-risk allergies, depending on their antimicrobial susceptibilities. Clinical trials are underway to evaluate the safety and immunogenicity of maternal anti-GBS vaccine candidates.

Residual protein analysis by SDS-PAGE in clinically manufactured BM-MSC products

Residual substances that are considered hazardous to the recipient must be removed from final cellular therapeutic products manufactured for clinical purposes. In doing so, quality rules determined by competent authorities (CAs) for the clinical use of tissue- and cell-based products can be met. In our study, we carried out residual substance analyses, and purity determination studies of trypsin and trypsin inhibitor in clinically manufactured bone marrow-derived mesenchymal stromal/stem cell products, using the sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) method. Despite being a semiquantitative method, SDS-PAGE has several benefits over other methods for protein analysis, such as simplicity, convenience of use, and affordability. Due to its convenience and adaptability, SDS-PAGE is still a commonly used method in many laboratories, despite its limits in dynamic range and quantitative precision. Our goal in this work was to show that SDS-PAGE may be used effectively for protein measurement, especially where practicality and affordability are the major factors. The results of our study suggest a validated method to guide tissue and cell manufacturing sites for making use of an agreeable, accessible, and cost-effective method for residual substance analyses in clinically manufactured cellular therapies.

Antibiotic allergy prevalence and documentation quality in Massachusetts long-term care facilities: A cross-sectional survey

BACKGROUND

Antimicrobial resistance poses a significant global health challenge, particularly affecting older adults who are more susceptible to infections and their complications. Accurate diagnosis and documentation of antibiotic allergies are essential for effective antimicrobial stewardship. Despite the recognized overdiagnosis of antibiotic allergies, comprehensive studies on this subject in long-term care (LTC) settings are limited.

OBJECTIVE

To determine the point prevalence of antibiotic allergies and documentation quality in Massachusetts LTC facilities.

METHODS

We conducted a cross-sectional, 1-day point prevalence survey from July 1, 2023, to March 31, 2024, across 20 participating LTC facilities in Massachusetts in partnership with the Massachusetts Department of Public Health. The survey assessed the prevalence and documentation of antibiotic allergies among 2345 residents. Multivariable logistic regression was used to explore associations between documented penicillin allergy and demographic factors, including non-penicillin antibiotic allergies.

RESULTS

The overall point prevalence of documented antibiotic allergies was 39.1%, with the most frequently reported classes being penicillins at 23.1%, sulfonamides at 15.4%, and cephalosporins at 5.2%. Significant documentation gaps were identified, with up to 92.8% of the allergy records found to be incomplete. Factors associated with documented penicillin allergies included female sex (adjusted odds ratio [aOR], 1.50; 95% CI, 1.16-1.94), White race (aOR, 1.92; 95% CI, 1.25-2.94), having allergies to non-penicillin antibiotics (aOR, 2.89; 95% CI, 2.33-3.59), and receipt of antibiotic (aOR, 2.13; 95% CI, 1.68-2.71).

CONCLUSION

The high prevalence of documented antibiotic allergies and the notable deficiencies in their documentation underscore the urgent need for enhanced antibiotic evaluation, documentation practices, and penicillin delabeling in LTC facilities.

Safe Penicillin Allergy Delabeling in Primary Care: A Systematic Review and Meta-Analysis

BACKGROUND

Ten percent of the population is labeled as allergic to penicillin(s), when in fact 90% of these labels are inappropriate. Recent studies have shown that inpatient delabeling by a direct drug challenge (dDC) is safe in low-risk patients. However, there is a need for outpatient and nonallergist delabeling.

OBJECTIVE

To assess the safety of delabeling low-risk adults by means of dDC in primary care.

METHODS

We searched the MEDLINE, Embase, and Cochrane Library databases from inception to March 15, 2022 (updated June 5, 2023) for studies performing dDC in adults in primary care or other outpatient settings. Two researchers independently screened studies for eligibility. The data extraction and critical appraisal were performed by 1 reviewer, and we pooled the results in a meta-analysis.

RESULTS

Of 2138 results, 12 studies (1070 participants) were eligible for inclusion. Three studies evaluated delabeling in primary care and 9 studies in an outpatient hospital setting. There were no critical adverse events during dDC. No reaction occurred in 97.13% of the 1070 patients, who previously labeled as penicillin-allergic, and were safely delabeled. Ten patients (<1%) developed an immediate reaction: 3 had self-limiting reactions and 7 needed antihistaminics, steroids, epinephrine, and/or salbutamol.

CONCLUSIONS

No serious allergic reactions are observed during direct amoxicillin challenge in adults in an outpatient setting. However, with the exception of 1 recent report, these studies are of low to moderate quality. Nonspecialist delabeling is promising, but further research is required on correct risk stratification and safety assessment in large cohort studies evaluating dDC in primary care.

Leveraging implementation science theories to develop and expand the use of a penicillin allergy de-labeling intervention

BACKGROUND

Penicillin allergy is the most frequently reported drug allergy, yet most patients can tolerate the drug if challenged. Despite this discrepancy, large scale penicillin allergy de-labeling interventions have not been widely implemented in many health care systems. The application of a multi-method implementation science approach can provide key tools to study this evidence to practice gap and provide insight to successfully operationalize penicillin allergy evaluation in real-world clinical settings.

METHODS

We followed a four-step process that leverages qualitative analysis to design evidence-based, actionable strategies to develop an intervention. First, we specified the clinician-perceived barriers to penicillin allergy de-labeling (intervention targets). We then mapped intervention targets onto Theoretical Domains Framework (domains and constructs) and found the root causes of behavior. Next, we linked root causes of behavior with intervention functions (BCW). In the final step, we synthesized participants' suggestions for process improvement with implementation strategies aligning with the intervention functions.

RESULTS

Evidence-based strategies such as focused education and training in penicillin allergy evaluation can address knowledge and confidence barriers reported by frontline clinicians. Other key strategies involve developing a system of champions, improving communications systems, and restructuring the healthcare team. Implementation mapping can provide a powerful multi-method framework to study, design, and customize intervention strategies.

CONCLUSION

Empowering clinicians beyond allergy specialists to conduct penicillin allergy assessments requires designing new workflows and systems and providing additional knowledge to those clinicians.

Covalent penicillin-protein conjugates elicit anti-drug antibodies that are clonally and functionally restricted

Many archetypal and emerging classes of small-molecule therapeutics form covalent protein adducts. In vivo, both the resulting conjugates and their off-target side-conjugates have the potential to elicit antibodies, with implications for allergy and drug sequestration. Although β-lactam antibiotics are a drug class long associated with these immunological phenomena, the molecular underpinnings of off-target drug-protein conjugation and consequent drug-specific immune responses remain incomplete. Here, using the classical β-lactam penicillin G (PenG), we probe the B and T cell determinants of drug-specific IgG responses to such conjugates in mice. Deep B cell clonotyping reveals a dominant murine clonal antibody class encompassing phylogenetically-related IGHV1, IGHV5 and IGHV10 subgroup gene segments. Protein NMR and x-ray structural analyses reveal that these drive structurally convergent binding modes in adduct-specific antibody clones. Their common primary recognition mechanisms of the penicillin side-chain moiety (phenylacetamide in PenG)-regardless of CDRH3 length-limits cross-reactivity against other β-lactam antibiotics. This immunogenetics-guided discovery of the limited binding solutions available to antibodies against side products of an archetypal covalent inhibitor now suggests future potential strategies for the 'germline-guided reverse engineering' of such drugs away from unwanted immune responses.

Efficacy of the PEN-FAST score in a French cohort of patients with reported allergy to penicillins

Introduction

Various clinical decision-making tools for penicillin allergy have been developed to guide delabeling strategies.

Objective

To evaluate the penicillin allergy PEN-FAST decision score in a retrospective cohort of patients, adults and children, with penicillin-reported allergy.

Methods

This monocentric retrospective cohort included patients with penicillin-reported allergy. All patients underwent penicillin allergy testing using skin tests and/or drug challenge. The PEN-FAST score sensitivity, specificity, negative (NPV) and positive (PPV) predictive values, and the area under the receiver operating characteristics curve (AUC) were calculated.

Results

Two hundred and fourteen patients were included (64 children and 150 adults). Allergy was confirmed in 52 cases (24%). A PEN-FAST score <3 points showed a poor discrimination capacity for the whole population (AUC = 0.66; 95% CI: 0.58-0.75), while it demonstrated a better discrimination capacity in the adults group (AUC = 0.71; 95% CI: 0.63-0.80). The sensitivity to identify penicillin allergy using this cutoff of less than 3 points was 0.67 (95% CI: 0.52-0.80); specificity, 0.58 (95% CI: 0.48-0.68); PPV, 0.43 (95% CI: 0.32-0.55); and NPV, 0.78 (95% CI: 0.68-0.87).

Conclusions

Although our data confirm a rather good discrimination value of a PEN-FAST score <3 points, its low negative predictive value (78%) did not advocate for its use as an accurate, simple and cost-effective clinical decision-making tool to effectively reduce the number of penicillin skin tests required before direct oral challenge. Further studies are required to improve the predictive capacity of the PEN-FAST score.

Penicillin Allergy in China: Consequences of Inappropriate Skin Testing Practices and Policies

Penicillins are the most frequently prescribed class of medications worldwide and first-line antibiotic of choice for most bacterial infections. They are also commonly labelled as the culprit of drug 'allergy'; leading to obligatory use of second-line antibiotics, suboptimal antibiotic therapy and increased antimicrobial resistance. However, the majority of reported penicillin 'allergy' labels are found to be incorrect after allergy testing, emphasising the importance of proper drug allergy testing and evaluation. Penicillin skin testing (PST) remains an important component of drug allergy diagnosis; however, its practice and policies significantly differ across the world. Inappropriate and non-evidence-based PST practices can lead to consequences associated with allergy mislabelling. Even within different regions of China, with a population exceeding 1.4 billion, there are marked differences in the implementation, execution and interpretation of PST. This review aims to examine the differences in PST between Mainland China, Hong Kong and the rest of the world. We critically analyse the current practice of 'pre-emptive' PST in Mainland China, which has a significant false-positive rate leading to high levels of penicillin allergy mislabelling. Non-evidence-based practices further compound the high false-positive rates of indiscriminatory PST. We postulate that inappropriate PST policies and practices may exacerbate the mislabelling of penicillin allergy, leading to unnecessary overuse of inappropriate second-line antibiotics, increasing antimicrobial resistance and healthcare costs. We advocate for the importance of more collaborative research to improve the contemporary workflow of penicillin allergy diagnosis, reduce mislabelling and promote the dissemination of evidence-based methods for allergy diagnosis.

Gram-negative bacteria recognition and photodynamic elimination by Zn-DPA based sensitizers

The abuse and overuse of antibiotics let drug-resistant bacteria emerges. Antibacterial photodynamic therapy (APDT) has shown outstanding merits to eliminate the drug-resistant bacteria via cytotoxic reactive oxygen species produced by irradiating photosensitizer. However, most of photosensitizers are not effective for Gram-negative bacteria elimination. Herein conjugates of NBS, a photosensitizer, linked with one (NBS-DPA-Zn) or two (NBS-2DPA-Zn) equivalents of zinc-dipicolylamine (Zn-DPA) have been designed to achieve the functional recognition of different bacteria. Due to the cationic character of NBS and metal transfer channel effect of Zn-DPA, NBS-DPA-Zn exhibited the first regent to distinguish P. aeruginosa from other Gram-negative bacteria. Whereas NBS-2DPA-Zn showed broad-spectrum antibacterial effect because the two arm of double Zn-DPA enhanced interactions with anionic membranes of bacteria, led the bacteria aggregation and thus provided the efficacy of APDT to bacteria and corresponding biofilm. In combination with a hydrogel of Pluronic, NBS-2DPA-Zn@gel shows promising clinical application in mixed bacterial diabetic mouse model infection. This might propose a new method that can realize functional identification and elimination of bacteria through intelligent regulation of Zn-DPA, and shows excellent potential for antibacterial application.

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.

The Cost of Developing and Implementing an Antepartum Referral Program for Penicillin Allergy Evaluation at a Single Academic Tertiary Care Hospital

OBJECTIVE

Approximately 10% of pregnant individuals report a penicillin allergy, yet most are not truly allergic. Allergy verification during pregnancy is safe and recommended; however, many hospitals lack the infrastructure to execute testing. Our aim was to evaluate the cost of developing and implementing a penicillin allergy referral program for pregnant individuals at an academic institution and to compare costs of care between patients who were referred and not referred through the program.

STUDY DESIGN

We conducted an economic analysis of our institution's antepartum penicillin allergy referral program. We prospectively collected detailed resource utilization data and conducted the analysis from the program's perspective, accounting for costs related to program development, allergy verification, antibiotic cost, and delivery hospitalization. Costs were compared between patients who were referred for evaluation versus patients who were not referred using bivariate tests as well as quantile regression adjusting for baseline differences. A sensitivity analysis was performed for allergy testing cost. All cost estimates were inflation adjusted to 2021 U.S. dollars.

RESULTS

The startup cost of program development and educational initiatives was $19,920, or 86 per patient. The median allergy evaluation cost was $397 (interquartile range: $303-663). There was no significant difference in maternal (median: $13,579 vs. 13,999, p = 0.94) or neonatal (median: $3,565 vs. 3,577, p = 0.55) delivery hospitalization cost or antibiotic cost (median: $1.57 vs. 3.87, p = 0.10) between referred and nonreferred patients. Overall, the total cost per person did not differ significantly between study groups (median: $18,931 vs. 18,314, p = 0.69).

CONCLUSION

The cost of developing a penicillin allergy referral program in pregnancy was modest and did not significantly alter short-term cost of care with potential for long-term cost benefit. Verification of a reported penicillin allergy is an integral part of antibiotic stewardship, and the pregnancy period should be utilized as an important opportunity to perform this evaluation.

KEY POINTS

· The cost of developing and implementing an antepartum penicillin allergy referral program is modest.. · Program cost did not significantly alter short-term cost with a potential for long-term cost benefit.. · Penicillin allergy verification is an important part of antibiotic stewardship and should be expanded..

[Penicillin allergy: A label that is not forever]

Self-reported penicillin allergy is highly prevalent. Different studies estimate that 10% of the population is labeled as such. This label, confirmed or suspected, forces us to take precautions and replace the antibiotic treatment of choice (frequently beta-lactams) with other 2nd or 3rd choice alternatives with worse overall results: side effects, resistance, costs, etc. The penicillin allergy label, once placed, remains in the medical record. It is only confirmed in less than 5% of patients, either because it has been placed inappropriately or because over time the sensitivity decreases and may disappear. Penicillin Allergy Decision Rule -PEN-FAST- is a validated and simple clinical prediction rule that estimates the risk of presenting an allergic reaction. Its use, together with algorithms that involve primary care in the study and delabeling of low-risk patients, can change our clinical practice.

Beta-lactam allergy in patients: an antibiotic stewardship challenge

BACKGROUND

Patients are commonly reported as being allergic to beta-lactam (BL) antibiotics. However, many patients with this reported allergy are able to receive BL treatments because they do not have true allergies. In many cases these are simply intolerances due to side effects reported as an allergy. Delabelling these patients leads to better clinical outcomes, optimal antibiotic usage, decreased bacterial resistance and reduced healthcare costs. Therefore, the aims of this study were to identify incorrectly labelled BL allergies in hospitalised patients and to assess antibiotic use in delabelled patients in order to establish a quality indicator to optimise antimicrobial treatments.

METHODS

A prospective study was conducted in which hospitalised patients treated with antimicrobial drugs and labelled as 'BL-allergic' were identified by clinical pharmacists. An allergist assessed whether patients were suitable candidates for a skin test or oral challenge. The Allergy Service removed 'BL-allergic' labels if negative results were obtained. Delabelled patients were followed up by clinical pharmacists to study the use of BL antibiotics as a result of the delabelling programme.

RESULTS

A total of 176 suspected allergic patients were identified and 91 (51.7%) were tested either by a skin test or oral challenge based on the patient indicators. Seven (16.4%) patients tested were allergic to BL antibiotics, 76 (83.5%) were totally delabelled and eight (0.1%) were partially delabelled. Thirty-two (38.1%) delabelled patients required antibiotic treatment in another inpatient or outpatient setting, of whom 27 (84.3%) patients with a new infectious episode received BL treatments while five (15.7%) continued to receive antimicrobial treatments without BL.

CONCLUSION

After the implementation of a protocol to detect incorrect BL allergy labels, 83.5% of the patients in this cohort were completely delabelled. This shows that there is a clear opportunity to optimise the use of antibiotics by delabelling 'BL-allergic' patients.

A critical appraisal of acute sore throat guidelines using the AGREE II instrument: a scoping review

BACKGROUND

Conflicting international guidelines exist on the management of sore throat by antibiotics.

OBJECTIVES

To assess with the Appraisal of Guidelines for Research and Evaluation II (AGREE) instrument the quality of guidelines for uncomplicated acute group A beta-haemolytic streptococcal (GABHS) sore-throat. To make a sensitivity analysis restricted to guidelines with a rigour of development score higher than 60% and to describe their recommendations on scores, tests, and antibiotic therapy, including their justification.

METHODS

A guideline literature review of acute GABHS sore throat, published between January 2000 and December 2019 in primary care and secondary care. The PubMed database, the Canadian Medical Association Infobase on Clinical Practice Guidelines and the International Network Guidelines were used. The quality of guidelines was assessed using the AGREE II instrument. The guidelines were classified into 2 categories: high-quality guidelines had to rate >60% for the rigour of development score, the others were classified as low-quality guidelines.

RESULTS

Significant heterogeneity between the 15 guidelines concerned the scores of the 6 assessment domains. Among them, 6 guidelines presented a score above 60% with regards to the rigor of development domain and used a systematic literature search method, citing meta-analyses of recent randomised clinical trials. Most of the 6 high-quality guidelines no longer recommended the systematic use of diagnostic scores and tests, nor antibiotic therapy to prevent acute rheumatic fever or loco-regional complications, except for high-risk patients.

CONCLUSION

Major discrepancies emphasise the need for only high-quality guidelines, based on adequately assessed evidence. Restricted antibiotic prescriptions to severe cases or high-risk patients would avoid antibiotic resistance.

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.

The Safety of Aztreonam Versus Ceftazidime in Patients Labeled With Penicillin Allergy: A Cohort Study

PURPOSE

Penicillin allergy is the most common drug allergy among hospitalized patients. Traditionally, aztreonam is recommended for patients labeled with penicillin allergy (PLWPA) in our institutional empirical antibiotic guidelines. Due to a global aztreonam shortage in December 2022, the antimicrobial stewardship unit recommended ceftazidime as a substitute. There is a paucity of real-world data on the safety profile of ceftazidime in PLWPA. Hence, we evaluated tolerability outcomes of ceftazidime use in PLWPA.

METHODS

This retrospective cohort study compared PLWPA in Singapore General Hospital who received aztreonam (October 2022-December 2022) or ceftazidime (December 2022-February 2023). Patients were stratified according to their risk of allergic reaction (AR) based on history of penicillin allergy. The severity of AR was based on the Delphi study grading system. The primary outcome was development of AR after initiation of aztreonam or ceftazidime. The secondary tolerability outcomes include hepatotoxicity and neurotoxicity.

FINDINGS

There were 168 patients in the study; 69 were men (41.1%) and the median age was 69 years (interquartile range: 59-76 years). Incidence of AR was statistically similar in both arms: 1 of 102 patients (0.98%) in the aztreonam arm vs 2 of 66 patients (3.03%) in the ceftazidime arm (P = 0.33). The patient in the aztreonam arm was deemed at medium risk of having an AR and developed localized rashes (grade 1). Both patients in the ceftazidime arm were deemed at high risk of AR and developed localized skin reaction (grade 1). Hepatotoxicity was observed in 1 patient prescribed aztreonam. No patients in the ceftazidime arm developed adverse events.

IMPLICATIONS

Ceftazidime appears to be better tolerated and cheaper compared with aztreonam in PLWPA, and serves as an antimicrobial stewardship strategy to conserve broader-spectrum antibiotics use.

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.

Maximizing Adherence and Minimizing Time to Antibiotics: A Multidisciplinary Institutional Trauma Bay Protocol for Single Antibiotic Prophylaxis in Open Fractures

OBJECTIVES

To determine if a multidisciplinary institutional protocol can optimize the time to antibiotic (Abx) administration for open fractures (openFx) and improve compliance with the administration of Abx prophylaxis during trauma activation.

METHODS

DESIGN

Retrospective pre-post study design.

SETTING

Single Level II Trauma Center.

PATIENT SELECTION CRITERIA

All patients who triggered a trauma activation with suspected openFx and were treated according to the institutional single antibiotic regimen were eligible for inclusion. Patients were excluded if fractures did not involve the appendicular skeleton. Patients treated before implementation of a standardized institutional protocol where premixed IV bags of antibiotics were stocked in automated dispensing systems within ED trauma bays (January 2021-October 2022) were defined as the "pre" group and those treated following implementation the "post" group.

OUTCOME MEASURES AND COMPARISONS

The primary outcome was time from trauma bay arrival to antibiotic aministration, measured in minutes, with comparisons made between preprotocol and postprotocol implementation. Secondary outcomes for comparison included rates (%) of time to Abx <60 minutes, allergic reactions, acute kidney injury, ototoxicity, surgical site infection, multi-drug-resistant organisms identified in blood or biopsy cultures in cases requiring reoperation, and Clostridium difficile infection in the gastrointestinal system, confirmed by stool test results, within 30 days.

RESULTS

Twenty-four patients (mean age 39.5 ± 16.3 years) met the criteria after protocol implementation compared with 72 patients (mean age 34.3 ± 14.8 years) before implementation. Implementation of the institutional protocol resulted in a significant reduction in the time to Abx administration for openFx from 87.9 ± 104.6 minutes to 22.2 ± 12.8 minutes in the postprotocol group ( P < 0.001). In addition, only 53% in the preprotocol group received Abx within 60 minutes compared with 96% in postprotocol group ( P < 0.001). Post hoc power analysis revealed that the study was powered at 92% (effect size = 0.72) to detect a significant difference between the preprotocol and postprotocol groups.

CONCLUSION

This study provides evidence that a multidisciplinary institutional protocol for the administration of Abx prophylaxis can be an effective strategy for optimizing the time to Abx administration in cases of suspected openFx. This protocol may be implemented in other trauma centers to optimize time to Abx administration for openFx.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Eliciting the barriers and enablers towards anaesthetists giving penicillin-based antibiotic prophylaxis to low-risk patients who have had their penicillin allergy label removed as part of a preoperative delabelling process

Background

Some penicillin allergy labels can be removed by non-allergy specialists by direct oral challenge, but there is reluctance amongst anaesthetists to give penicillin to these patients. We aimed to assess anaesthetist beliefs about giving penicillin to patients delabelled by direct oral challenge.

Methods

A survey, developed using the Theoretical Domains Framework, was circulated to anaesthetists within a regional research network in England. Domains were rated using 5-point Likert scales. Overall and group medians were used to dichotomize domains rated by group into 'relatively important/unimportant' and 'relative enabler/barrier'.

Results

We received 257 responses from six hospitals (response rate 49.7%). Seven domains were rated as important for all stakeholder groups and hospitals: Knowledge, Skills, Belief in Capabilities, Belief in Consequences, Memory/Attention/Decisions, Environmental Context and Resources, and Emotions. Social and Professional Role was also important to all respondents except those in one hospital. Intentions and Optimism were rated as important for some groups/hospitals and unimportant for others. All four other domains were rated as unimportant for all groups/hospitals. All domains rated as important were enablers for all groups/hospitals, with the exception of Memory/Attention/Decisions and Emotions, which were rated as discordant barriers/enablers between groups. This means they were acting as a barrier for some staff groups/hospitals and an enabler for others. Barrier domains (Reinforcement, Goals, Social Influences, Behavioural Regulation) were all rated unimportant.

Conclusions

Behavioural influences on giving penicillin prophylaxis to a delabelled patient are complex and nuanced. These findings could inform targeted interventions, both across and within hospitals and staff groups.

Proactive risk stratification and low-risk penicillin allergy delabeling by an antimicrobial stewardship pharmacist

Penicillin (PCN) allergy delabeling is an important component of antimicrobial stewardship; however, widespread implementation has lagged. We found that most patients had low-risk PCN allergy histories eligible for delabeling without skin testing. Pharmacist-led risk stratification and drug challenge expanded access to delabeling independently from an Allergy/Immunology service.

Pediatric Residents Knowledge of Penicillin Allergy

Penicillin allergy knowledge has not been evaluated specifically in the pediatric resident population. An anonymous electronic survey was distributed to all the pediatric residents in a single residency program to ascertain knowledge of penicillin allergies and allergy history taking skills. Responses among each resident class were compared using the Fisher exact test, 2-tailed. A total of 46 (52%) of 88 pediatric residents completed the survey. Only 63% reported to have had prior penicillin allergy education. All residents incorrectly identified low-risk symptoms as high-risk symptoms. The knowledge of penicillin allergy was poor across all training levels with no improvement over the duration of training. There is large support in the literature for de-labeling penicillin allergy in patients. Pediatric residents evaluate patients in childhood when most of the allergy labeling occurs. We need to consider strategies for incorporating penicillin allergy education in pediatric residency training.

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).

Maternal Group B Streptococcus Prophylaxis Improvement using an Electronic Medical Record Dynamic Order Set

OBJECTIVE

 To develop and implement a Group B Streptococcal (GBS) dynamic order set to improve adherence to the American College of Obstetricians and Gynecologists/Centers for Disease Control and Prevention (ACOG/CDC) guidelines.

STUDY DESIGN

 A team of information technology and clinical experts developed a dynamic order block. The content was patterned after the CDC "Prevent GBS" mobile app. It was then embedded in the labor and delivery/induction order set and piloted at a single high-volume obstetric unit. Following the pilot and incorporation of the 2019 ACOG update of the CDC guidelines, the order set was rolled out in five additional hospitals within a region of a large health system. Information on GBS prophylaxis performance before and after implementation was available for the pilot site and four of the additional hospitals. Information before implementation was obtained electronically from electronic medical record (EMR) laboratory and pharmacy data and supplemented by manual chart review. Postimplementation data were obtained from discrete order set EMR data elements. Adherence to the guidelines before and after were compared using chi-squared test.

RESULTS

 There were 7,114 deliveries before implementation and 4,502 after implementation. Preterm delivery occurred in 6.8 and 6.9%, respectively. There was an increase in appropriate treatment of preterm patients (positive and unknown GBS) delivering after implementation (88.7-99.1%, p < 0.001). More patients were reported to have a penicillin allergy before implementation than after implementation (14.7 vs. 11.1%, respectively, p = 0.01). Associated changes in therapy noted after implementation included a nonsignificant decrease in the proportion reporting a high-risk allergy (50.3 vs. 41.9%, p = 0.18), an increase in the appropriate use of clindamycin and vancomycin (64.4 vs. 92.3%, p < 0.001) and a decrease in clindamycin use in those without sensitivity testing.

CONCLUSION

 Routine universal use of a dynamic admission labor/induction order set was associated with high and improved adherence to GBS prophylaxis guidelines.

KEY POINTS

· Lapses in GBS prophylaxis are associated with early-onset GBS disease.. · Preterm delivery and penicillin allergic patients are commonly associated with lapses in prophylaxis.. · Dynamic EMR order set use can improve adherence to clinical guidelines..

Functional nanomaterials as photosensitizers or delivery systems for antibacterial photodynamic therapy

Bacterial infection is a global health problem that closely related to various diseases threatening human life. Although antibiotic therapy has been the mainstream treatment method for various bacterial infectious diseases for decades, the increasing emergence of bacterial drug resistance has brought enormous challenges to the application of antibiotics. Therefore, developing novel antibacterial strategies is of great importance. By producing reactive oxygen species (ROS) with photosensitizers (PSs) under light irradiation, antibacterial photodynamic therapy (aPDT) has emerged as a non-invasive and promising approach for treating bacterial infections without causing drug resistance. However, the insufficient therapeutic penetration, poor hydrophilicity, and poor biocompatibility of traditional PSs greatly limit the efficacy of aPDT. Recently, studies have found that nanomaterials with characteristics of favorable photocatalytic activity, surface plasmonic resonance, easy modification, and high drug loading capacity can improve the therapeutic efficacy of aPDT. In this review, we aim to provide a comprehensive understanding of the mechanism of nanomaterials-mediated aPDT and summarize the representative nanomaterials in aPDT, either as PSs or carriers for PSs. In addition, the combination of advanced nanomaterials-mediated aPDT with other therapies, including targeted therapy, gas therapy, and multidrug resistance (MDR) therapy, is reviewed. Also, the concerns and possible solutions of nanomaterials-based aPDT are discussed. Overall, this review may provide theoretical basis and inspiration for the development of nanomaterials-based aPDT.

Phytochemical and pharmacological properties of the genus Tamarix: a comprehensive review

The genus Tamarix in the Tamaricaceae family consists of more than 100 species of halophyte plants worldwide that are mainly used to improve saline-alkali land and for coastal windbreaks, sand fixation, and afforestation in arid areas. A considerable number of species in this genus are also used as traditional medicines to treat various human diseases, especially in Asian and African countries. This review presents a comprehensive summary of 655 naturally occurring compounds derived from the genus Tamarix, categorized into flavonoids (18.0%), phenols (13.9%), tannins (9.3%), terpenoids (10.5%), essential oils (31.0%), and others (17.3%). The investigation revealed that the crude extracts and phytochemicals of this genus exhibited significant therapeutic potential, including anti-inflammatory, anti-Alzheimer, anticancer, antidiabetic, antibacterial, and antifungal activities. Six species of Tamarix have anticancer effects by causing cancer cell death, inducing autophagy, and stopping cell division. Seven species from the same genus have the potential for treating diabetes by inhibiting α-glycosidase activity, suppressing human islet amyloid polypeptide, regulating blood glucose levels, and modulating autophagy or inflammation. The focus on antibacterial and antidiabetic effects is due to the presence of volatile oil and flavonoid components. Extensive research has been conducted on the biological activity of 30 constituents, including 15 flavonoids, 5 phenols, 3 terpenoids, 1 tannin, and 6 others. Therefore, future research should thoroughly study the mechanisms of action of these and similar compounds. This is the most comprehensive review of the phytochemistry and pharmacological properties of Tamarix species, with a critical assessment of the current state of knowledge.