Proven Non-β-Lactam Antibiotic Allergy in Children

How to Define and Manage Low-Risk Drug Allergy Labels

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

Drug allergy evaluation in children with suspected mild antibiotic allergy

Background

Adverse antibiotic reactions caused by an immunological mechanism are known as allergic reactions. The percentage of reported antibiotic allergies is likely to differ from the one validated after a drug provocation test (DPT) with the culprit antibiotic. This study aimed to compare the percentage of children who were thought to be allergic to a certain antibiotic with those who have a true allergy, as confirmed by DPTs. We also validated Skin Prick Tests (SPTs) and Intradermal Tests (IDTs) by assessing their sensitivity and specificity, in diagnosing antibiotic allergies using DPT as the gold standard. Furthermore, we investigated epidemiological risk factors such as personal and family history of atopic disease and eosinophilia.

Methods

Children with a history of possible allergic reaction to an antibiotic underwent a diagnostic procedure that included: (1) Eosinophil blood count, (2) SPTs, (3) IDTs and (4) DPTs. The parameters were compared with Pearson's Chi-Square and Fisher's Exact Test. Several risk factors that were found significant in univariate analysis, such as personal and family history of atopic disease, and positive SPTs and IDTs were examined with multiple logistic regression analysis to see if they were related to a higher risk for a positive DPT.

Results

Semi-synthetic penicillin was the most common group of antibiotics thought to cause allergic reactions in this study. Overall, 123 children with a personal history of an adverse reaction to a certain antibiotic, were evaluated. In 87.8% of the cases, the symptoms had occurred several hours after administration of the culprit antibiotic. Both SPTs and IDTs had low sensitivity but high specificity. Moreover, they had a high positive predictive value (PPV). In contrast, eosinophilia was not recognized as a risk factor. Seventeen patients (13.8%) had a true antibiotic allergy, as confirmed by a positive DPT. A positive IDT was a strong predictor of a positive DPT, along with a positive personal and family history of atopy.

Conclusion

SPTs and IDTs are very reliable in confirming antibiotic allergy when found positive. A negative result of a SPT highly predicts a negative DPT. A positive IDT and a positive personal and family history of atopy were recognized as significant risk factors for antibiotic allergy.

Clarithromycin hypersensitivity in children: Is there a link with β-lactam hypersensitivity?

BACKGROUND

Clarithromycin hypersensitivity is reported as the most common cause of non-β-lactam antibiotic allergy in children. Clarithromycin is frequently prescribed in cases of suspected β-lactam hypersensitivity. Oral provocation tests stand as the gold standard to confirm drug hypersensitivity as diagnostic value of skin tests is variable. We analyzed the frequency of true clarithromycin hypersensitivity ratio and its relationship with β-lactam allergy among children with suspected clarithromycin hypersensitivity and evaluated the diagnostic value of skin tests.

METHODS

The study included 160 children referred with suspected clarithromycin hypersensitivity. Clinical history and allergy workups including skin tests or/and oral provocation tests were retrieved from medical records.

RESULTS

Oral provocation test confirmed clarithromycin hypersensitivity rate was 5.6% (n = 9/160). Skin tests with clarithromycin showed positivity in 32.6% (n = 29/89) of the tested patients. The sensitivity of clarithromycin skin tests was negligible, and specificity was 73.9% (95% confidence interval [CI], 64.7-81.8). Eighty-eight of the patients (55%) reported that they had previously tolerated a β-lactam antibiotic. β-lactam hypersensitivity was suspected in 40% (n = 64/160) of the patients (simultaneous [n = 10], sequential [n = 19], distant form [n = 35]) in relation with clarithromycin usage. β-lactam hypersensitivity (95% CI, 2.1-70.6, p = .005) and sequential usage of clarithromycin after the development of a rash with amoxicillin-clavulanic acid (95% CI, 2.0-96.4, p = .007) were found as risk factors for confirmed clarithromycin hypersensitivity.

CONCLUSION

The frequency of confirmed clarithromycin hypersensitivity was found low among suspected patients. Oral provocation test is crucial for definite diagnosis. Confirmed β-lactam allergy may be attributed as a risk factor for clarithromycin hypersensitivity, particularly clarithromycin treatment after a developing rash with amoxicillin-clavulanic acid in sequential usage.

Pediatric Drug Allergies: Updates on Beta-Lactam, Nonsteroidal Anti-Inflammatory Drug, and Chemotherapeutic Reactions

Adverse drug reactions are frequently reported in pediatric patients. In this review article, the authors discuss pediatric drug allergies with emphasis on the most common culprits, beta-lactam antibiotics and non-steroidal anti-inflammatory drugs. The authors also discuss reactions to non-beta-lactam antibiotics and chemotherapeutics. Skin testing has not yet been validated for many drugs, although notable exceptions include penicillin and carboplatin. The gold standard for diagnosis in most cases remains drug challenge, and the need for penicillin skin testing prior to oral provocation challenge has been questioned in recent studies. Successful desensitizations have also been reported with several drugs.

Non-β-Lactam Antibiotic Hypersensitivity Reactions

OBJECTIVES

Antibiotics are among the most common prescriptions in children, and non-β-lactam antibiotics (NBLAs) account for almost half of those prescribed in Australian pediatric hospitals. Despite this, data on NBLA hypersensitivity in children are limited. This study describes reported hypersensitivity reactions to NBLAs in children and the results of allergy evaluation.

METHODS

Children with a suspected NBLA allergy who had skin testing and/or an intravenous or oral challenge test (OCT) between May 2011 and June 2018 were included. Patients were excluded if they were >18 years old or did not complete the allergy evaluation for any reason other than allergic reaction.

RESULTS

Over the 7-year study period, 141 children had 150 allergy evaluations of 15 different NBLAs. The median time from the initial reported reaction to allergy evaluation was 1.9 (range 0.1-14.9) years. Overall, 27 of the 150 (18.0%) challenge tests to NBLAs had positive results, with the rate of positive OCT results being highest for trimethoprim-sulfamethoxazole (15 of 46; 32.6%) and macrolides (8 of 77; 10.4%). Although 4 children reported initial anaphylactic reactions, no patients had severe symptoms on rechallenge or required adrenaline. Of the challenges that had positive results, the majority of children (23 of 27; 85.2%) had symptoms on repeat challenge similar to those that were initially reported.

CONCLUSIONS

Overall, 8 of 10 children with NBLA allergy could be delabeled. On average, patients waited 1.9 years to be rechallenged. Timely access to allergy evaluation to delabel these patients is needed to preserve first-line antibiotics.

Protocols for drug allergy desensitization in children

Introduction: When a drug hypersensitivity reaction is proven, desensitization protocols allow the reintroduction of the molecule in patients for whom such therapy is essential. Through drug desensitization (DDS), a temporary immune tolerance is maintained for the single course of a specific therapy. In pediatrics, indications for such a procedure include children with chronic diseases, severe infectious diseases and/or malignancies, who have a proven drug hypersensitivity.Areas covered: We ran a search on PubMed and Web of Science for papers on DDS and on DDS in children. Most protocols and recommendations on DDS focus on adults and have been adapted for children. The best candidates for desensitization are children with a history of immediate, IgE-mediated drug allergy, but this therapy may be applied also in nonallergic hypersensitivities and in non-immediate reactions. Most protocols in literature focus on antibiotics, especially beta-lactams, on chemotherapeutic agents, and on monoclonal antibodies.Expert opinion: Pediatric allergists should cooperate with specialists in infectious diseases and onco-hematology to provide DDS to children in need. Standardized protocols and international guidelines are still needed to optimize such treatment and to implement it in clinical daily practice.

Pediatric Drug Allergies: Updates on Beta-Lactam, Nonsteroidal Anti-Inflammatory Drug, and Chemotherapeutic Reactions

Adverse drug reactions are frequently reported in pediatric patients. In this review article, the authors discuss pediatric drug allergies with emphasis on the most common culprits, beta-lactam antibiotics and non-steroidal anti-inflammatory drugs. The authors also discuss reactions to non-beta-lactam antibiotics and chemotherapeutics. Skin testing has not yet been validated for many drugs, although notable exceptions include penicillin and carboplatin. The gold standard for diagnosis in most cases remains drug challenge, and the need for penicillin skin testing prior to oral provocation challenge has been questioned in recent studies. Successful desensitizations have also been reported with several drugs.

Macrolide Allergic Reactions

Macrolides are antimicrobial agents that can be used to treat a variety of infections. Allergic reactions to macrolides occur infrequently but can include minor to severe cutaneous reactions as well as systemic life-threatening reactions such as anaphylaxis. Most reports of allergic reactions occurred in patients without prior exposure to a macrolide. Cross-reactivity among macrolides may occur due to the similarities in their chemical structures; however, some published literature indicates that some patients can tolerate a different macrolide. Most published reports detailed an allergic reaction to erythromycin. Desensitization protocols to clarithromycin and azithromycin have been described in the literature. The purpose of this article is to summarize macrolide-associated allergic reactions reported in published literature. An extensive literature search was conducted to identify publications linking macrolides to hypersensitivity reactions.

Recent developments in drug hypersensitivity in children

Introduction: Drug allergy is an important public health problem that causes 0.4-10.3% of hospital admissions in children. The epidemiology, clinical spectrum, diagnosis, and management of drug hypersensitivity reactions (DHRs) differ in pediatric and adult patients. However, the same algorithms used in adults have often been applied in the pediatric population due to a lack of evidence in the literature. Areas covered: In this review, we aimed to discuss recent developments in the area of pediatric DHRs based on the growing body of literature advancing our understanding of the epidemiology, clinical aspects, and diagnostic approaches to DHRs in children. Expert opinion: Misdiagnosis, under-diagnosis, and self-diagnosis are common problems related to drug allergies in children. Viral infections are particularly frequent in children and make diagnosis difficult. Identifying true DHR is a key step in the management of drug allergy in children. Therefore, a complete allergy work-up with standardized drug allergy tests is necessary. In order to eliminate non-standardized tests, future studies including larger numbers of children should be conducted to determine more accurate standardized tests for diagnosing DHRs in the pediatric population.

Pediatric Drug Hypersensitivity

PURPOSE OF REVIEW

Pediatric drug hypersensitivity is a rapidly evolving field. The purpose of this paper is to review the current state of pediatric drug hypersensitivity and highlight new developments in diagnosis and management.

RECENT FINDINGS

This paper will discuss the safety and use of risk stratification to proceed directly to oral challenge without prior skin testing for β-lactam reactions. We review unique aspects of pediatric drug challenges and desensitizations. It is important to accurately diagnose pediatric drug hypersensitivity reactions through a detailed history, physical examination, and available diagnostic testing. Understanding of the underlying mechanism leads to appropriate classification which is necessary to direct management. The decision to perform drug challenge, desensitization, or recommend avoidance of a medication can have a significant impact on a patient's treatment. Utilization of weight-based dose and infusion rate adjustments for current drug challenge and desensitization protocols optimize success.

Recent Advances in Clinical Allergy and Immunology

Allergic diseases are of great concern because of their high prevalence, which is still rising in several regions, their impact on patients' physical and psychological health, the huge burden they place on patients' quality of life, as well as the socioeconomic consequences that they cause. Recent research has provided new data on both genetic and environmental risk factors of atopic/allergic diseases. The application of new technologies such as "omics" has allowed a better understanding of the pathogenesis and has helped with the identification of therapeutic targets. Immense progress has been made in developing and applying novel, targeted therapies, for example for asthma and urticaria. Intensive efforts are being made to find biomarkers that help to classify patients, to identify their potential responsiveness to specific therapies, and to monitor the disease severity. Based on recent insights in the pathogenesis of food allergy and drug hypersensitivity, novel strategies for diagnostics, allergen avoidance, and induction of tolerance have been developed. Here, we summarize important findings in the field of clinical allergy and immunology with a special focus on asthma, allergic rhinitis, atopic dermatitis, food allergy, urticaria, angioedema, and drug hypersensitivity.

Rash diagnostics: an update on the diagnosis of allergic rashes

PURPOSE OF REVIEW

The purpose of this review is to summarize recent research regarding the diagnosis of allergic rashes and to suggest future directions for the promotion of accurate diagnosis and endotype specification.

RECENT FINDINGS

Multiple cohort studies demonstrate that with appropriate clinical evaluation, drug allergy labels can be removed in up to 90% of cases. Genetic tests can predict severe adverse cutaneous drug reactions in some cases and in vitro tests are being sought to identify causative drugs in others. Biomarkers to define endotypes of atopic dermatitis are needed to predict which patients will benefit from evolving targeted therapies. Hyperspectral imaging is a rapidly evolving technology in medical diagnostics; additional research is needed to demonstrate whether this promising technology can be used to distinguish allergic rashes and/or endotypes in atopic dermatitis.

SUMMARY

Diagnostic tools for the assessment of allergic rashes are primitive in that they frequently rely on challenges to ascertain whether suspected allergens were causative. Validated in vitro tests with high sensitivity and specificity for drug allergies would benefit the field, particularly in delayed type reactions, as would identification of any hyperspectral signatures that could identify endotypes in atopic dermatitis.

Use of Epinephrine in Patients with Drug-Induced Anaphylaxis: An Analysis of the Beijing Pharmacovigilance Database

BACKGROUND

Few studies assessing the use of epinephrine in drug-induced anaphylaxis (DIA) in the hospital setting are available. We utilized the Beijing Pharmacovigilance Database (BPD) to evaluate the appropriateness of epinephrine for DIA management.

METHODS

DIA cases collected in the BPD from January 2004 to December 2014 were adjudicated and analyzed for demographics, causative drugs, clinical signs, outcomes, initial treatment, route, dosing, and cardiovascular adverse events (CAE) of epinephrine.

RESULTS

DIA was primarily caused by antibiotics (38.4%), radiocontrast agents (11.9%), traditional Chinese medicine injections (10.9%), and chemotherapeutic drugs (10.3%). Only 708 (59.5%) patients received epinephrine treatment. Patients who received epinephrine were more likely to experience wheezing (p < 0.001) and respiratory arrest (p < 0.001). Among 518 patients with a complete record of the epinephrine administration route, the percentage of patients receiving it by intramuscular (IM) injection, subcutaneous (SC) injection, intravenous (IV) bolus injection, or IV continuous infusion was 16.9, 31.5, 43.5, and 8.1%, respectively. Among the 427 patients with a record of both the administration route and the dosing, an overdose was more likely with IV bolus (94.1%) in contrast to IM injection (56.6%; p < 0.001) or SC injection (43.7%; p < 0.001). Among the patients analyzed for CAE (n = 349), 17 patients accounted for 19 CAE, and 13 (76.5%) of these patients were overdosed with epinephrine.

CONCLUSION

Underuse, inappropriate IV bolus use, and overdosing were the 3 major problems with epinephrine use in DIA in China. Educational training for health care professionals on the appropriate use of epinephrine in managing anaphylactic reactions is suggested.

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.