Antibiotic hypersensitivity reactions and approaches to desensitization

Ethics of antibiotic allergy

Antibiotic allergies are commonly reported among patients, but most do not experience reactions on rechallenge with the same agents. These reported allergies complicate management of infections in patients labelled as having penicillin allergy, including serious infections where penicillin-based antibiotics are the first-line (most effective and least toxic) treatment option. Allergy labels are rarely questioned in clinical practice, with many clinicians opting for inferior second-line antibiotics to avoid a perceived risk of allergy. Reported allergies thereby can have significant impacts on patients and public health, and present major ethical challenges. Antibiotic allergy testing has been described as a strategy to circumvent this dilemma, but it carries limitations that often make it less feasible in patients with acute infections or in community settings that lack access to allergy testing. This article provides an empirically informed ethical analysis of key considerations in this clinical dilemma, using Staphylococcus aureus bacteraemia in patients with penicillin allergies as a case study. We argue that prescribing first-line penicillin-based antibiotics to patients with reported allergies may often present a more favourable ratio of benefits to risks, and may therefore be more ethically appropriate than using second-line drugs. We recommend changes to policy-making, clinical research and medical education, in order to promote more ethically acceptable responses to antibiotic allergies than the status quo.

First-Dose Antimicrobial Infusion Reactions in Patients Enrolled in Outpatient Parenteral Antimicrobial Therapy Services

After receiving a monitored first-dose antimicrobial infusion at an infusion center, 6 of 93 (6%) patients enrolled in outpatient parenteral antimicrobial therapy services experienced an immediate reaction, none of which were consistent with immunoglobulin E-mediated reactions. These findings suggest it would be reasonable to forgo monitoring for most patients receiving first-dose intravenous antimicrobials outpatient.

Trimethoprim/sulfamethoxazole desensitization in an HIV-positive patient with previous Stevens-Johnson syndrome; a failed study

Drug-induced Stevens-Johnson syndrome (SJS) is a rare but life-threatening hypersensitivity reaction. Drug desensitization might be considered in drug-allergic patients with no therapeutic alternative. A 29-year-old man with a recent diagnosis of HIV and HBV (CD4 count: 4 cells/mm3) who has been receiving Trimethoprim/sulfamethoxazole (TMP/SMX) for Pneumocystis pneumonia (PCP) prophylaxis was admitted at Imam Khomeini hospital complex affiliated to Tehran University of Medical Sciences, with the diagnosis of SJS due to TMP/SMX. After 45 days of supportive care, the patient was a candidate for TMP/SMX desensitization due to our region's unavailability of alternative agents. A 9-day desensitization protocol was used, but the patient complained about diarrhea with severe pain in the rectal mucosa, and macules developed over his lips again on the third day. As a result, the desensitization process immediately stopped, and after the signs and symptoms were resolved, the patient was discharged with Clindamycin tablet 600 mg TDS. Unfortunately, two weeks after discharge, the patient experienced acute kidney injury (AKI) and expired after two dialysis sessions.

Korean Guidelines for Use of Antibiotics for Intra-abdominal Infections in Adults

The guidelines are intended to provide practical information for the correct use of antibiotics for intra-abdominal infections in Korea. With the aim of realizing evidence-based treatment, these guidelines for the use of antibiotics were written to help clinicians find answers to key clinical questions that arise in the course of patient care, using the latest research results based on systematic literature review. The guidelines were prepared in consideration of the data on the causative pathogens of intra-abdominal infections in Korea, the antibiotic susceptibility of the causative pathogens, and the antibiotics available in Korea.

Antibiotic desensitization as a potential tool in antimicrobial stewardship programs: retrospective data analysis and systematic literature review

OBJECTIVES

Antibiotic allergy labels (AAL) are related to worse therapeutic results. Strategies to improve the management of these patients, such as the implementation of antibiotic desensitization, are essential for Antimicrobial Stewardship Programs (ASP). The aim of our study is to evaluate the efficacy and safety of antibiotic desensitization procedures for the management of patients with AAL.

METHODS

A retrospective study from 2015 to 2022 was performed to describe all antibiotic desensitization conducted in our institution, within the framework of ASP. A systematic literature review using electronic databases, such as PubMed, was also done to identify studies describing antibiotic desensitization between 2000 and 2022.

RESULTS

Sixteen antibiotic desensitization protocols were carried out in our institution. In fourteen cases, the desensitization was successfully completed, and the antibiotic could be used to treat the infection. In the systematic review, twenty-two studies were included, with a total of 202 desensitization episodes . In 97% of them, the desensitization was completed successfully. No desensitization-related mortality was observed neither in our cohort nor in literature review.

CONCLUSIONS

Antibiotic desensitization strategies should be considered a safe and effective tool that can be included in ASP for patients with a high risk of or confirmed allergy to penicillin.

Promoting β-lactam utilization through suppression of electronic medical record cross-allergy alerts

DISCLAIMER

In an effort to expedite the publication of articles related to the COVID-19 pandemic, AJHP is posting these manuscripts online as soon as possible after acceptance. Accepted manuscripts have been peer-reviewed and copyedited, but are posted online before technical formatting and author proofing. These manuscripts are not the final version of record and will be replaced with the final article (formatted per AJHP style and proofed by the authors) at a later time.

PURPOSE

Current literature surrounding management of patients with reported β-lactam allergies focuses on allergy delabeling. Standard clinical decision support tools have not been optimized to be compatible with the currently accepted cross-reaction rate of 1% to 2%. This potentially promotes use of non-β-lactam antibiotics, which are often not first-line therapy and may carry increased risks. The impact of electronic medical record (EMR) clinical decision support tool optimization on utilization of β-lactam antibiotics in β-lactam-allergic patients was evaluated.

METHODS

A retrospective pre-post β-lactam cross-allergy EMR alert suppression quality improvement intervention cohort study of β-lactam-allergic adult inpatients prescribed antibiotics was conducted. Preintervention baseline data were collected for an initial cohort admitted during September 2018. The intervention, in which clinical decision support rules were updated to display β-lactam cross-sensitivity allergy alerts only for β-lactam-allergic patients with documentation of organization-defined high-severity reactions of anaphylaxis, hives, and shortness of breath, was implemented August 20, 2019. The postintervention cohort included patients admitted during September 2019.

RESULTS

A 91% increase in the percentage of β-lactam-allergic patients who received a β-lactam agent at any time during their admission was noted after the intervention (26.6% vs 51%, P < 0.001). Statistically significant decreases in prescribing of alternative antibiotic classes were seen for fluoroquinolones (decrease from 45.3% to 26%, P < 0.001), aminoglycosides (decrease from 9.4% to 2.9%, P = 0.002), and aztreonam (decrease from 30% to 16.7%, P < 0.001).

CONCLUSION

EMR β-lactam cross-allergy alert optimization consistent with current literature significantly improved the utilization of alternative β-lactam subclasses, mostly through β-lactam prescribing as initial therapy in β-lactam-allergic patients.

Anaphylaxis to Drugs, Biological Agents, and Vaccines

Anaphylaxis is a multi-system syndrome resulting from the release of mediators from mast cells and basophils. Drugs are common causes. Anaphylaxis to certain drugs, vaccines, and biological agents present clinical challenges, and merit referral to a board-certified allergist/immunologist for further evaluation and management.

Potency and selectivity indices of Myristica fragrans Houtt. mace chloroform extract against non-clinical and clinical human pathogens

This study assessed the antimicrobial, toxicity, and phytochemical profiles of Myristica fragrans extracts. Different solvent extracts were tested for antimicrobial activity against clinical and reference microbial strains, using disc and well diffusion assays and microdilution techniques. Antioxidant potential was investigated using 2,2-diphenyl-1-picryhydrazyl (DPPH) assays. Cytotoxicity assay was conducted against human umbilical vein endothelial cells (HUVECs) using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Acute toxicity was assessed in laboratory Swiss albino mice at a single dose of 2,000 mg/kg body weight for 14 days. To assess the phytochemical constituents, spectrophotometric and gas chromatography-mass spectrometry (GC-MS) methods were used. The chloroform extract revealed antimicrobial potencies against the Gram-positive bacteria and C. albicans with minimum inhibitory concentrations. In the DPPH assay, the IC50 value of the chloroform extract was determined to be 1.49 mg/mL. The phenolic and flavonoid contents were 26.64 ±  0.1 mg of gallic acid equivalents/g and 8.28  ± 0.1 mg quercetin equivalents/g, respectively. The IC50 value was determined to be 49 µg/mL against the HUVEC line. No mortality or morbidity was observed. GC-MS analysis indicated the presence of 2-cyclopenten-1-one (44.72%) as a major compound. The current results provide scientific support for the use of M. fragrans in folk medicine.

A new rapid titration protocol for lamotrigine that reduces the risk of skin rash

Objective

Lamotrigine is one of the most widely used antiepileptic drugs, but it has a critical issue of a skin rash if the starting dose is too high or the escalation rate is too rapid. We investigated the efficacy and safety of a novel and rapid titration protocol for lamotrigine that takes only 11 days to reach a daily dose of 200 mg.

Methods

We prospectively enrolled 33 adult patients (age 18‐85) who were diagnosed with epilepsy and started lamotrigine administration for the first time at a single tertiary hospital. Our new protocol starts with a subthreshold dose of the drug and then administers a stepwise‐incremental dose until reaching the full therapeutic dose within 11 days.

Results

Of 29 patients analyzed, only two (6.9%) experienced idiosyncratic skin rash before the first follow‐up visit at 2 weeks (±3 days). In addition, a therapeutic concentration was reached in more than 75% of studied patients after 2 weeks of lamotrigine administration.

Significance

These findings demonstrate the value of the novel tolerance induction protocol for lamotrigine, which could widen the available application of lamotrigine in various situations. However, this study is a preliminary study limited by a small number of patients and its nonrandomized and open‐label design, so the current protocol needs more rigorous clinical evaluations before the application to the real clinical setting.

Antibiotics: Conventional Therapy and Natural Compounds with Antibacterial Activity-A Pharmaco-Toxicological Screening

Antibiotics are considered as a cornerstone of modern medicine and their discovery offers the resolution to the infectious diseases problem. However, the excessive use of antibiotics worldwide has generated a critical public health issue and the bacterial resistance correlated with antibiotics inefficiency is still unsolved. Finding novel therapeutic approaches to overcome bacterial resistance is imperative, and natural compounds with antibacterial effects could be considered a promising option. The role played by antibiotics in tumorigenesis and their interrelation with the microbiota are still debatable and are far from being elucidated. Thus, the present manuscript offers a global perspective on antibiotics in terms of evolution from a historical perspective with an emphasis on the main classes of antibiotics and their adverse effects. It also highlights the connection between antibiotics and microbiota, focusing on the dual role played by antibiotics in tumorigenesis. In addition, using the natural compounds with antibacterial properties as potential alternatives for the classical antibiotic therapy is discussed.

Safe administration of drug desensitizations in pediatric patients

PURPOSE

Patients with certain types of allergic reactions to medication may safely receive the culprit medication through an elaborate allergy procedure called a drug desensitization. Nurses play a key role in this process which is only performed when a certain medication is absolutely indicated as optimal therapy. Nurses are instrumental in the planning stages of drug desensitizations for coordination of interdisciplinary care and anticipation of adverse effects. Thus, it is paramount that nurses performing this procedure understand the mechanism of desensitizations and have access to the resources needed to safely complete these procedures in pediatric patients.

CONCLUSION

Excellence in nursing clinical acumen and a detailed order set are essential to patient safety during dug desensitization. With the following methodology and coordination by nursing, we have had great success at Children's Hospital Los Angeles in over one hundred drug desensitizations in pediatric patients which allowed them to received first line therapies. We have created order sets from published references and years of clinical experience. The nursing care of adult patients undergoing drug desensitization procedures is well described in the literature but few resources exist for pediatric nurses. There is paucity of published nursing resources for pediatric drug desensitizations. Repeated PubMed searches for "pediatric drug desensitizations" in 2019-2020, revealed only one recent reference geared toward physicians.

PRACTICE IMPLICATIONS

With appropriate training, staffing, and coordination, drug desensitizations can be safely performed in pediatric patients with close observation by a multi-disciplinary team. The bedside nurse has a pivotal role as coordinator and clinician for these high-risk resource-intensive procedures.

Validation of a novel causality assessment scale for adverse events in non-small cell lung carcinoma patients treated with platinum and pemetrexed doublet chemotherapy

Aim:

Accurate causality assessment (CA) of adverse events (AEs) is important in clinical research and routine clinical practice. The Naranjo scale (NS) used for CA lacks specificity, leading to a high rate of false positive causal associations. NS is a simple scale for CA; however, its limitations have reduced its popularity in favour of other scales. We therefore attempted to improvise the algorithm by addressing specific lacunae in NS.

Methods:

We attempted to modify the existing NS by (a) changing the weightage given to certain responses, (b) achieving higher resolution to certain responses for delineating drug related and unrelated AEs and (c) modifying the slabs for classification of association as ‘likely’ and ‘unlikely’. The new scale, named as the Sharma-Nookala-Gota (SNG) algorithm, was evaluated in a training set of 19 AEs in a tertiary care cancer hospital in western India, and further validated in a set of 104 AEs. Consensus of four physician opinion was taken as gold standard for comparison.

Results:

Of the 19 AEs in the training set, 6 were described by the treating physician as ‘not related’ and 13 as related to the drug. The SNG algorithm had 100% concordance with physician opinion, whereas the NS had only 73.7% concordance. NS showed a tendency to misclassify AEs as ‘related’ when they were indeed ‘not related’. In the validation set of 104 AEs, NS and SNG algorithms misclassified 30 and 2 AEs, respectively, leading to a concordance of 70.2% and 98.1%, respectively, with physician opinion.

Conclusion:

Decisive modifications of the NS resulted in the SNG scale, with superior specificity while retaining sensitivity against the gold standard.

Plain Language Summary

SNG algorithm – A novel tool for causality assessment of adverse drug reactions

Adverse events (AEs) can cause increased morbidity, hospitalisation, and even death. Hence it is essential to recognise AEs and to establish their correct causal relationship to a drug. Many causality assessment methods, scales and algorithms are available to assess the relationship between an AE and a drug. The Naranjo algorithm is most commonly employed in spite of its many drawbacks as it is simple to use. Concerns have been raised regarding the performance of the scale, and researchers have tried to answer them, but none of them could address all issues satisfactorily. We too experienced many problems while using it in our routine clinical practice and in clinical trials. For instance, the Naranjo scale is non-specific and shows a bias toward implicating the drug as the causal factor for AEs. This improper assessment has often led to drug discontinuation, thereby compromising the efficacy of treatment. Hence, we modified the existing Naranjo scale to a new one (the Sharma-Nookala-Gota – SNG algorithm) to address these shortcomings. We piloted the SNG causality assessment algorithm in patients suffering from AEs due to various drugs. The SNG algorithm was found to have good concordance with the physicians’ assessment of causality. As a next step, we validated the SNG algorithm in patients receiving a standard drug combination of pemetrexed and carboplatin for lung cancer combination. Out of the 104 AEs observed in 65 patients, the SNG causality assessment algorithm showed good concordance (except in two cases) with the physicians’ decision of causality assessment, while the Naranjo algorithm was not so successful. Hence, the SNG algorithm can be a better guide for causality assessment of AEs.

Graded Dalbavancin Challenge in a Patient With Severe Vancomycin Hypersensitivity Reaction

Cross-reactivity should be considered when treating patients with a previous hypersensitivity reaction within the same class of antibiotics that share similar chemical structures. This case report describes a patient with severe hypersensitivity reaction to vancomycin who successfully tolerated a dalbavancin graded challenge.

Glycopeptide Hypersensitivity and Adverse Reactions

Glycopeptides, such as vancomycin and teicoplanin, are primarily used in the treatment of methicillin-resistant Staphylococcus aureus (MRSA) infections, such as cellulitis, endocarditis, meningitis, pneumonia, and septicemia, and are some of the most commonly prescribed parenteral antimicrobials. Parenteral glycopeptides are first-line therapy for severe MRSA infections; however, oral vancomycin is used as a first-line treatment of Clostridioides difficile infections. Also, we currently have the longer-acting lipoglycopeptides, such as dalbavancin, oritavancin, and telavancin to our armamentarium for the treatment of MRSA infections. Lastly, vancomycin is often used as an alternative treatment for patients with β-lactam hypersensitivity. Common adverse effects associated with glycopeptide use include nephrotoxicity, ototoxicity, and Redman Syndrome (RMS). The RMS is often mistaken for a true allergy; however, it is a histamine-related infusion reaction rather than a true immunoglobulin E (IgE)-mediated allergic reaction. Although hypersensitivity to glycopeptides is rare, both immune-mediated and delayed reactions have been reported in the literature. We describe the various types of glycopeptide hypersensitivity reactions associated with glycopeptides and lipoglycopeptides, including IgE-mediated reactions, RMS, and linear immunoglobulin A bullous dermatosis, as well as describe cross-reactivity with other glycopeptides.

A Practical Guide for Managing Antibiotic Allergies in the Emergency Department

Up to 30% of patients report at least one antibiotic allergy, but oftentimes these antibiotic allergies are misdiagnosed. In fact, of the 10% of patients reporting penicillin allergies, 90%-98% are not truly allergic. In an era of increasing antibiotic resistance coupled with a limited number of new antibiotics, evaluating antibiotic allergies is critical in providing optimal patient care. Differentiating adverse drug reactions from antibiotic allergies may seem like a daunting task for clinicians and providers, especially in the emergency department, where decisions are made quickly. However, a systemic approach, including medical record review coupled with patient and/or family interview, is vital in managing patients with antibiotic allergies. Inappropriate, alternative antibiotics are frequently chosen due to patient allergies, and data suggest higher rates of broad-spectrum antibiotic use, antibiotic resistance, and poor outcomes as a result. Herein, we review antibiotic selection in patients reporting antibiotic allergies in the emergency department.

Hypersensitivity reactions to bicarbonate dialysate containing acetate: a case report with literature review

Although hemodialysis-hypersensitivity reactions have various causes, only a few cases of hypersensitivity to acetate dialysate accompanied by fever have been reported. We present the case of a 69-year-old hemodialysis patient who was admitted due to fever after dialysis. He had undergone online hemodiafiltration using acetate-free citrate-containing dialysate. After admission, we switched to acetate-containing bicarbonate dialysate. He was diagnosed with pneumonia and treated with ceftriaxone. However, fever that occurred post dialysis persisted, displaying a gradual elevation in CRP level and eosinophils (up to 9.7 mg/dL and 3774 cells/μL, respectively). After a series of negative workups for infection and dialysis membrane allergy, we suspected that acetate-containing bicarbonate dialysate to be the cause of the allergic reaction and switched to acetate-free bicarbonate dialysate. Consequently, eosinophil count decreased and the fever abated. The drug-induced lymphocyte stimulation test finding (for acetate dialysate) was positive, and he was diagnosed with acetate dialysate-induced hypersensitivity reactions. The condition was not detected earlier due to the complications associated with pneumonia.

The challenge of de-labeling penicillin allergy

BACKGROUND

Even though 8%-25% of most populations studied globally are labeled as penicillin allergic, most diagnoses of penicillin allergy are made in childhood and relate to events that are either not allergic in nature, are low risk for immediate hypersensitivity, or are a potential true allergy that has waned over time. Penicillin allergy labels directly impact antimicrobial stewardship by leading to use of less effective and broader spectrum antimicrobials and are associated with antimicrobial resistance. They may also delay appropriate antimicrobial therapy and lead to increased risk of specific adverse healthcare outcomes. Operationalizing penicillin allergy de-labeling into a new arm of antimicrobial stewardship programs (ASPs) has become an increasing global focus.

METHODS

We performed an evidence-based narrative review of the literature of penicillin allergy label carriage, the adverse effects of penicillin allergy labels, and current approaches and barriers to penicillin allergy de-labeling. Over the period 1928-2018 in Pubmed and Medline, search terms used included "penicillin allergy" or "penicillin hypersensitivity" alone or in combination with "adverse events," "testing," "evaluation," "effects," "label," "de-labeling," "prick or epicutaneous," and "intradermal" skin testing, "oral challenge or provocation," "cross-reactivity," and "antimicrobial stewardship".

RESULTS

Penicillin allergy labels are highly prevalent, largely inaccurate and their carriage may lead to unnecessary treatment and inferior outcomes with alternative agents as well as adverse public health outcomes such as antibiotic resistance.

CONCLUSIONS

Operationalizing penicillin allergy de-labeling as an aspect of ASP has become an increasing global focus. There is a need for validated approaches that optimally combine the use of history and ingestion challenge with or without proceeding formal skin testing to tackle penicillin allergy efficiently within complex healthcare systems. At the same time, there is great promise for penicillin allergy evaluation and de-labeling as an individual and public health strategy to reduce adverse healthcare outcomes, improve antimicrobial stewardship, and decrease healthcare costs.

Sulfonamide desensitization in solid organ transplant recipients: A protocol-driven approach during the index transplant hospitalization

Trimethoprim-sulfamethoxazole (TMP-SMX) is the first-line agent for Pneumocystis jiroveci pneumonia (PJP) prophylaxis for solid organ transplant (SOT) recipients because of its efficacy for this indication, extended antimicrobial coverage, and favorable cost. Reported sulfonamide allergy is not uncommon and often results in TMP-SMX avoidance. Desensitization offers an efficacious and cost-effective alternative to TMP-SMX avoidance. Herein, we reviewed our experience with desensitization during the index transplant hospitalization among 52 SOT recipients with history of a non-anaphylactic sulfonamide allergy. Of those enrolled in the desensitization protocol, 92% (48/52) completed the protocol, with nearly 80% (41/52) still on TMP-SMX at 3 months without adverse reaction. Eleven patients discontinued TMP-SMX (7 for allergic reactions and 4 for non-allergic reasons) and switched to pentamidine. A cost savings of $575 per desensitization was calculated based on annual wholesale drug prices, for a total savings of $23 575. Additionally, the protocol did not delay discharge in any patient nor was it associated with any severe allergic reactions. These findings suggest TMP-SMX desensitization is safe and effective in SOT recipients with a history of non-anaphylactic, non-life-threatening sulfonamide hypersensitivity.

Antibiotic Hypersensitivity Mechanisms

Antibiotics are commonly prescribed to treat a variety of bacterial infections. As with all medications, hypersensitivity reactions may occur and clinicians should be able to recognize them accurately and recommend appropriate management. Antibiotic related hypersensitivity reactions may be one of four different types: Type I reactions, which are IgE mediated and may lead to anaphylaxis; Type II reactions that are antibody-mediated and may result in thrombocytopenia, neutropenia, or hemolytic anemia; Type III reaction that involves an immune complex formation such as vasculitis; and Type IV reactions that consist of four subtypes and typically include a rash of varying level of severity with or without systemic signs and symptoms. Herein, we describe the mechanisms of different types of allergic reactions to commonly prescribed antibiotics and offer recommendations for management. Further, we briefly refer to antibiotic reactions that mimic hypersensitivity reactions but are not immune mediated, such as pseudoallergies and serum sickness-like reactions.

Antimicrobial Desensitization: A Review of Published Protocols

Antimicrobial desensitization represents a last-line option for patients with no alternative therapies, where the benefits of this intensive process must outweigh the potential harm from drug exposure. The goal of antimicrobial desensitization procedures is to establish a temporary state of tolerance to drugs that may otherwise cause hypersensitivity reactions. While no universal antimicrobial desensitization protocols exist, this review critically analyzes previously published desensitization protocols. The purpose of this review is to provide a greater insight for clinicians and institutions to ensure desensitization procedures are efficacious while minimizing potential for patient harm. With an increasing rate of antimicrobial resistance and the critical need to preserve antimicrobial agents, desensitization may represent another option in our antimicrobial stewardship toolkit.

Comparison of Adverse Drug Reactions Between Patients Treated With Ceftaroline or Ceftriaxone: A Single-Center, Matched Cohort Study

Background

Little information is available on the relative tolerability of ceftaroline versus other cephalosporins in clinical practice. We sought to compare adverse drug reactions (ADRs) associated with ceftaroline with those associated with ceftriaxone in hospitalized patients.

Materials and Methods

This was a retrospective, single-center matched cohort (according to age, indication, and duration) study of patients treated with ceftaroline or ceftriaxone at the VA St Louis Health Care System between 29 October 2010 and 28 March 2017, to compare rates of ADRs between the agents. Patients included received ≥2 doses of either medication to treat osteomyelitis, acute bacterial skin and skin structure infection, blood stream infection, pneumonia, infective endocarditis, septic arthritis, prosthetic joint infection, or empyema. The primary and secondary outcomes were the composite of any ADR during therapy and any ADR leading to premature discontinuation of therapy. The ADRs evaluated included rash, neutropenia, acute kidney injury, eosinophilia, thrombocytopenia, transaminitis, and hyperbilirubinemia.

Results

After matching, 50 patients per group were included and analyzed. An ADR occurred in 20% (10 of 50) of patients treated with ceftriaxone and 16% (8 of 50) of those treated with ceftaroline (P = .60). Two percent (1 of 50) of those treated with ceftriaxone and 16% (8 of 50) treated with ceftaroline had therapy discontinued owing to an ADR (P = .03). The most common ADR was eosinophilia (3 of 50) in the ceftriaxone group and rash (5 of 50) in the ceftaroline group. Ceftaroline therapy was identified as an independent risk factor for an ADR requiring premature discontinuation (odds ratio, 10.2; 95% confidence interval, 1.19–87.8; P = .03).

Conclusions

Although there was no difference in the rates of ADRs between patients in the ceftriaxone and ceftaroline groups, significantly more ceftaroline-treated patients required premature discontinuation.

Self-reported beta-lactam intolerance: not a class effect, dangerous to patients, and rarely allergy

Introduction: About 8% of the United States population carries an unconfirmed penicillin 'allergy' in their medical record. Many physicians needlessly avoid other beta-lactam use in individuals with unconfirmed penicillin allergies. There is a significantly increased risk of developing serious antibiotic-resistant infections, and increased morbidity and mortality in those who report penicillin allergy. Areas covered: Within this study, we reviewed the relevant literature on self-reported beta-lactam allergy. We discuss how the myth of serious allergy to penicillin developed and then discuss and in detail clinically significant immunologically mediated hypersensitivity reactions. Following this discussion, we delineate the risks of not using a beta-lactam when it is the drug of choice and then discuss the epidemiology of beta-lactam-associated anaphylaxis, serious cutaneous adverse reactions, and serious systemic immunologically mediated reactions. Following these topics, we further discuss the consensus current best practices to de-label patients with reported penicillin allergy. Expert opinion: An unconfirmed allergy to penicillin offers considerable harm to patients. Many patients have low-risk allergy symptoms to penicillin who could likely tolerate the medication without having an allergic reaction. The current best practices to de-label reported penicillin allergy is the utilization of a single dose oral challenge, with 1 h of observation, in low-risk patients.

Phage Therapy in the Postantibiotic Era

Antibiotic resistance is arguably the biggest current threat to global health. An increasing number of infections are becoming harder or almost impossible to treat, carrying high morbidity, mortality, and financial cost. The therapeutic use of bacteriophages, viruses that infect and kill bacteria, is well suited to be part of the multidimensional strategies to combat antibiotic resistance. Although phage therapy was first implemented almost a century ago, it was brought to a standstill after the successful introduction of antibiotics. Now, with the rise of antibiotic resistance, phage therapy is experiencing a well-deserved rebirth. Among the admittedly vast literature recently published on this topic, this review aims to provide a forward-looking perspective on phage therapy and its role in modern society. We cover the key points of the antibiotic resistance crisis and then explain the biological and evolutionary principles that support the use of phages, their interaction with the immune system, and a comparison with antibiotic therapy. By going through up-to-date reports and, whenever possible, human clinical trials, we examine the versatility of phage therapy. We discuss conventional approaches as well as novel strategies, including the use of phage-antibiotic combinations, phage-derived enzymes, exploitation of phage resistance mechanisms, and phage bioengineering. Finally, we discuss the benefits of phage therapy beyond the clinical perspective, including opportunities for scientific outreach and effective education, interdisciplinary collaboration, cultural and economic growth, and even innovative use of social media, making the case that phage therapy is more than just an alternative to antibiotics.

Antibiotic allergy

Antibiotics are the commonest cause of life-threatening immune-mediated drug reactions that are considered off-target, including anaphylaxis, and organ-specific and severe cutaneous adverse reactions. However, many antibiotic reactions documented as allergies were unknown or not remembered by the patient, cutaneous reactions unrelated to drug hypersensitivity, drug-infection interactions, or drug intolerances. Although such reactions pose negligible risk to patients, they currently represent a global threat to public health. Antibiotic allergy labels result in displacement of first-line therapies for antibiotic prophylaxis and treatment. A penicillin allergy label, in particular, is associated with increased use of broad-spectrum and non-β-lactam antibiotics, which results in increased adverse events and antibiotic resistance. Most patients labelled as allergic to penicillins are not allergic when appropriately stratified for risk, tested, and re-challenged. Given the public health importance of penicillin allergy, this Review provides a global update on antibiotic allergy epidemiology, classification, mechanisms, and management.

Antibiotic allergy labels in hospitalized and critically ill adults: A review of current impacts of inaccurate labelling

Antibiotic allergy labels (AALs) are reported by approximately 20% of hospitalized patients, yet over 85% will be negative on formal allergy testing. Hospitalized patients with an AAL have inferior patient outcomes, increased colonization with multidrug-resistant organisms and frequently receive inappropriate antimicrobials. Hospitalized populations have been well studied but, to date, the impact of AALs on patients with critical illness remains less well defined. We review the prevalence and impact of AALs on hospitalized patients, including those in in critical care.

Beyond Penicillin: Rapid Desensitization for Specific Flucloxacillin Hypersensitivity

Beta-lactam therapy for severe staphylococcal infections is associated with superior outcomes, compared to non-beta-lactam therapy. For patients with immediate hypersensitivity to beta-lactams, desensitization has been widely employed to allow beta-lactam therapy, but published protocols for antistaphylococcal beta-lactams such as flucloxacillin are lacking. Here, we report a case and describe the desensitization protocol successfully used for a patient with isolated flucloxacillin immediate hypersensitivity, for whom a penicillin desensitization protocol would likely have resulted in an adverse drug reaction.

Evaluation of Pharmacy-Developed Antibiotic Desensitization Protocols

BACKGROUND

Parameters within reconstitution, storage, stability, and administration may be optimized according to the unique pharmacokinetics of each antibiotic to ensure a successful desensitization.

OBJECTIVE

The study aims to evaluate the successfulness and safety of antibiotic desensitization protocols developed by the pharmacy department at our institution.

METHODS

A retrospective study was conducted at an 800-bed, urban, tertiary care, academic medical center. A total of 36 patients 18 years of age or older, admitted to our intensive care units between March 2013 and July 2017, who underwent antibiotic desensitization utilizing our pharmacy developed protocols were included.

RESULTS

In 36 patients, 61 desensitization cases were identified and included; 17 (47%) were male, 27 (75%) were Caucasian, and the median age was 55 years (range 19-94). In all, 15 different antibiotics were administered for desensitization, with meropenem (n = 12, 20%), ampicillin (n = 7, 11%), piperacillin/tazobactam (n = 7, 11%), and penicillin (n = 7, 11%) being the most common; 59 (97%) of 61 desensitizations were completed successfully with or without experiencing reactions, and 53 (89%) of the successful desensitization cases were completed without reactions. Two cases were categorized as anaphylaxis, which was severe enough to terminate the desensitization process. Of the 59 cases successfully completed, the 6 (10%) cases that experienced reactions were managed successfully during desensitization with completion of the process. Conclusion and Relevance: The findings suggest that our pharmacy-developed antibiotic desensitization protocols are successful and safe and may be adapted by other institutions.

The anti-penicillin antibodies levels in sensitive and insensitive people to intradermal skin test

BACKGROUND

The hypersensitivity reaction to penicillin is a public health problem. Immunological responses to penicillin and other beta-lactam antibiotics can be classified into immediate and non-immediate responses. The immediate hypersensitivity is mediated by IgE; however, the non-immediate sensitivity is facilitated by other isotypes of antibody or T lymphocytes.

OBJECTIVE

This research detected the non-IgE antibody value against penicillin in allergic and normal people.

METHODS

Thirty-eight samples from patients with positive or negative intradermal skin testing results of penicillin allergy were included in this study. The total antibody and IgM levels against penicillin G were defined by in-house ELISA test.

RESULTS

The results showed a significant (P< 0.05) elevation in total immunoglobulin and non-IgM anti-penicillin antibody of sensitive groups; however, the anti-penicillin IgM was significantly greater in non-sensitive peoples.

CONCLUSIONS

Although the sensitized people to penicillin cannot be certainly detected with the total antibody, specific IgG and IgM value against penicillin, these values are good indicators for prediction of immediate and late response of the immune system to penicillin.

Successful desensitization to cloxacillin in a patient with sepsis, with infective endocarditis and clinical suspicion of hypersensitivity to penicillins, a case report

WHAT IS KNOWN AND OBJECTIVE

Beta-lactam antibiotic (BLA) therapy is frequently needed to treat infective endocarditis (IE). Hypersensitive reactions to BLA restrict BLA therapy in allergic patients. In the current case, we aim to describe the utility of desensitization (DS) in this context. Although the evidence is limited, DS is recommended.

CASE DESCRIPTION

This case report deals with a 79-year-old woman with a clinical suspicion of allergy to BLA and a methicillin-sensitive Staphylococcus aureus (MSSA) IE. A cloxacillin DS protocol was developed to enable treatment with cloxacillin.

WHAT IS NEW AND CONCLUSION

Alternative antibiotic treatments may be less effective or not available in MSSA IE. In this case report, DS allowed optimal cloxacillin treatment.

Hypersensitivity to alemtuzumab. A safe and effective desensitization protocol: A case report

We describe a successful desensitization to alemtuzumab in one patient diagnosed with T-cell prolymphocytic leukaemia. Alemtuzumab treatment was initiated during infusion number 18, the patient showed cutaneous eruption with a miliary pattern, despite premedication with corticosteroids and antihistamines. The eruption returned with successive alemtuzumab infusions (infusions 19, 20 and 21), remained present for longer and was more severe with each infusion. The patient was referred to our Allergy Unit as it was necessary to maintain alemtuzumab treatment. Total immunoglobulin E level was 3 UI/ml and specific immunoglobulin E against more common pneumo-allergens, food, latex and hamster were inferior to 0.35 UI/ml. Prick test using the undiluted drug (30 mg/ml) and intradermal tests using serial dilutions (1/10, 1/100) were performed. The result of alemtuzumab skin prick test was 4 mm. The intradermal skin test result was positive at 1/100 dilution (papule: 8 mm; erythema: 12 mm). The basophil activation test with alemtuzumab was performed concluding that 10% of the basophils were activated by alemtuzumab. The patient underwent alemtuzumab desensitization according to a 12-step protocol that resolved to be safe and efficacious. Our experience may be helpful for similar clinical cases where the therapeutic options are very limited and a life-threatening condition such T-cell prolymphocytic leukaemia is present. In addition, a careful risk/benefit ratio should be considered and accurate informed consent is mandatory.

Taking the challenge: A protocolized approach to optimize Pneumocystis pneumonia prophylaxis in renal transplant recipients

While trimethoprim-sulfamethoxazole is considered first-line therapy for Pneumocystis pneumonia prevention in renal transplant recipients, reported adverse drug reactions may limit use and increase reliance on costly and less effective alternatives, often aerosolized pentamidine. We report our experience implementing a protocolized approach to trimethoprim-sulfamethoxazole adverse drug reaction assessment and rechallenge to optimize prophylaxis in this patient cohort. We retrospectively reviewed 119 patients receiving Pneumocystis pneumonia prophylaxis prior to and after protocol implementation. Forty-two patients (35%) had 48 trimethoprim-sulfamethoxazole adverse drug reactions documented either at baseline or during the prophylaxis period, of which 83% were non-immune-mediated and 17% were immune-mediated. Significantly more patients underwent trimethoprim-sulfamethoxazole rechallenge after protocol implementation (4/22 vs 23/27; P = .0001), with no recurrence of adverse drug reactions in 74%. In those who experienced a new or recurrent reaction (26%), all were mild and self-limiting with only 1 recurrence of an immune-mediated reaction. After protocol implementation, aerosolized pentamidine-associated costs were reduced. The introduction of a standard approach to trimethoprim-sulfamethoxazole rechallenge in the context of both prior immune and non-immune-mediated reactions was safe and successful in improving the uptake of first-line Pneumocystis pneumonia prophylaxis in renal transplant recipients.

Vancomycin-Induced Leukocytoclastic Vasculitis and Acute Renal Failure Due to Tubulointerstitial Nephritis

BACKGROUND Methicillin-resistant Staphylococcus aureus (MRSA) bacteremia and sepsis are commonly treated with intravenous vancomycin. However, vancomycin treatment is associated adverse reactions, including skin rashes and nephrotoxicity. We present a case of acute renal failure due to acute tubulointerstitial nephritis associated with a diffuse leukocytoclastic vasculitic skin eruption following intravenous vancomycin treatment. CASE REPORT A 79-year-old Caucasian male patient was treated with intravenous vancomycin for MRSA bacteremia. Prior to treatment, his creatinine was normal at 0.6 mg/dl. He presented one week later with shortness of breath, lower limb edema, and acute renal failure. He had a diffuse maculopapular rash involving the trunk and both upper and lower extremities. A renal biopsy and left arm skin biopsy were examined histologically. The skin biopsy showed leukocytoclastic vasculitis. Renal biopsy showed some sclerosed glomeruli, some with mesangial proliferation, and tubulointerstitial inflammation with eosinophils and plasma cells and mild interstitial fibrosis. Although there was some renal arteriolosclerosis, no vasculitic changes were seen, and no vascular thrombosis was present. A diagnosis of leukocytoclastic vasculitis and acute tubulointerstitial nephritis secondary to intravenous vancomycin therapy was made. CONCLUSIONS Although skin reactions associated with drug therapy are common, vancomycin-associated dermal vasculitis is rare. Tubulointerstitial nephritis is also a rare association with vancomycin treatment. This case report has highlighted that patients being treated with intravenous vancomycin should be carefully observed for acute skin rashes and deterioration in renal function, which can be managed by ceasing treatment with vancomycin, steroid challenge, and preventing future exposure to similar antimicrobial agents.

Impact of an Integrated Antibiotic Allergy Testing Program on Antimicrobial Stewardship: A Multicenter Evaluation

Background

Despite the high prevalence of patient-reported antibiotic allergy (so-called antibiotic allergy labels [AALs]) and their impact on antibiotic prescribing, incorporation of antibiotic allergy testing (AAT) into antimicrobial stewardship (AMS) programs (AAT-AMS) is not widespread. We aimed to evaluate the impact of an AAT-AMS program on AAL prevalence, antibiotic usage, and appropriateness of prescribing.

Methods

AAT-AMS was implemented at two large Australian hospitals during a 14-month period beginning May 2015. Baseline demographics, AAL history, age-adjusted Charlson comorbidity index, infection history, and antibiotic usage for 12 months prior to testing (pre-AAT-AMS) and 3 months following testing (post-AAT-AMS) were recorded for each participant. Study outcomes included the proportion of patients who were "de-labeled" of their AAL, spectrum of antibiotic courses pre- and post-AAT-AMS, and antibiotic appropriateness (using standard definitions).

Results

From the 118 antibiotic allergy-tested patients, 226 AALs were reported (mean, 1.91/patient), with 53.6% involving 1 or more penicillin class drug. AAT-AMS allowed AAL de-labeling in 98 (83%) patients-56% (55/98) with all AALs removed. Post-AAT, prescribing of narrow-spectrum penicillins was more likely (adjusted odds ratio [aOR], 2.81, 95% confidence interval [CI], 1.45-5.42), as was narrow-spectrum β-lactams (aOR, 3.54; 95% CI, 1.98-6.33), and appropriate antibiotics (aOR, 12.27; 95% CI, 5.00-30.09); and less likely for restricted antibiotics (aOR, 0.16; 95% CI, .09-.29), after adjusting for indication, Charlson comorbidity index, and care setting.

Conclusions

An integrated AAT-AMS program was effective in both de-labeling of AALs and promotion of improved antibiotic usage and appropriateness, supporting the routine incorporation of AAT into AMS programs.

Improving Antimicrobial Stewardship by Antibiotic Allergy Delabeling: Evaluation of Knowledge, Attitude, and Practices Throughout the Emerging Infections Network

Antibiotic allergy testing (AAT) practices of Emerging Infections Network infectious disease physicians were surveyed. Although AAT was perceived to be necessary for removal of inappropriate or unnecessary allergy labels, there was limited access to any form of testing. In this study, we discuss current antibiotic allergy knowledge gaps and the development of AAT practices within antimicrobial stewardship programs, which will potentially improve antimicrobial prescribing.

Allergy to antibiotics in children: an overestimated problem

Antibiotics are the most prescribed drugs for children, and a relevant number of prescriptions are associated with the emergence of adverse events. Allergic reactions are the most frequently reported adverse events, with an incidence of up to 10% of all prescriptions. However, literature analysis has shown that allergy to antibiotics is generally overdiagnosed in children because in most cases the diagnosis is based only on the clinical history without a full allergy work-up. Consequently, children are often improperly deprived of narrow-spectrum antibiotics because of a suspected allergy to these drugs. β-Lactams, mainly penicillins, are more frequently involved as a cause of allergy to antibiotics, although allergic problems are reported for most of the antibiotic classes. Accurate diagnosis is essential for a precise definition of determination of allergy to a given drug. Diagnosis has to be based on history, laboratory tests and, when possible, on in vitro and drug provocation tests. Unfortunately, the allergological work-up is well structured only for β-lactam antibiotics, whereas for non-β-lactams few studies are available, with very limited experience in children. The main aim of this paper is to discuss the real relevance of allergy to antibiotics in children in order to provide physicians with the knowledge needed to establish an appropriate diagnostic allergy work-up and to make better use of antibiotic therapy.

Desensitization to ceftaroline in a patient with multiple medication hypersensitivity reactions

PURPOSE

The case of a patient with multiple medication hypersensitivity reactions and a methicillin-resistant Staphylococcus aureus (MRSA) infection who underwent desensitization to ceftaroline is reported.

SUMMARY

A 32-year-old Caucasian woman with asthma, gastroesophageal reflux disease, heart murmur, and major depression was admitted for MRSA cellulitis with a subcutaneous abscess along the left sternomanubrial joint and clavicular osteomyelitis secondary to port placement after gastric bypass surgery. The patient had an extensive history of hypersensitivity reactions. Pertinent documented allergies were as follows: penicillin (anaphylaxis), daptomycin (anaphylaxis), vancomycin (hives), linezolid (hives), ertapenem (rash), ciprofloxacin (rash), and tigecycline (rash). The patient also reported previous reactions to aztreonam (unknown) and gentamicin (hives). The pharmacy was consulted to develop a desensitization protocol for ceftaroline. The desensitization protocol used three serial dilutions of ceftaroline to make 14 sequential infusions with escalating doses. Intramuscular epinephrine, i.v. diphenhydramine, and i.v. methylprednisolone were ordered as needed for the development of immediate hypersensitivity reactions during or after administration of ceftaroline. The cumulative dose (574.94 mg) was administered intravenously over 225 minutes with no breakthrough symptoms reported during or after the desensitization protocol. Ceftaroline fosamil 600 mg i.v. every 12 hours was continued for six weeks.

CONCLUSION

Desensitization to ceftaroline was conducted for a patient with extensive history of hypersensitivity reactions to other drugs, including penicillin-induced anaphylaxis. Desensitization and subsequent treatment with full doses of ceftaroline were accomplished without apparent adverse effects.

Immunoglobulin E-mediated hypersensitivity reaction after intraperitoneal administration of vancomycin

Intraperitoneal (IP) vancomycin is widely used to treat Gram-positive peritonitis associated with peritoneal dialysis. There have been two cases of red man syndrome (RMS), a vancomycin-specific nonimmunologic reaction, associated with IP vancomycin. However, immune-mediated hypersensitivity reaction to IP vancomycin has not yet been reported. A 49 year old woman on continuous ambulatory peritoneal dialysis developed her first peritonitis episode. The patient was treated with IP vancomycin once/wk for 4 weeks. She experienced mild itching and flushing throughout her body for 1 day after the second treatment. Whenever vancomycin was administered, generalized urticaria and a prickling sensation developed, and the intensity increased gradually; however, these symptoms improved after vancomycin was discontinued. An allergic skin test was performed 6 weeks after the previous urticarial episode, and an intradermal skin test revealed a positive response to vancomycin. To our knowledge, this is the first case report of immunoglobulin E-mediated hypersensitivity reaction to IP vancomycin administration.