Recognising antibacterial hypersensitivity in children

Evaluation of Clinical Properties and Diagnostic Test Results of Cephalosporin Allergy in Children

INTRODUCTION

Beta-lactams (BLs) are one of the most frequent causes of drug hypersensitivity reactions (HRs), and cephalosporins are a widely used subclass of BLs, especially in children. The aim of this study was to evaluate the clinical features and diagnostic test results of pediatric patients evaluated for suspected cephalosporin allergy.

METHODS

This study included patients who presented to our pediatric allergy clinic with a history of reactions attributed to cephalosporins between January 1, 2011, and December 31, 2019, and whose diagnostic tests were completed for the diagnosis.

RESULTS

This study included 120 pediatric patients and 69 (57.5%) of them were girls. The median age was 38.63 (interquartile range 10.5-85.7) months. Reactions occurring within 1 h of drug intake were reported in 33 patients (27.5%). Reactions were maculopapular rash in 55 (45.8%) patients, urticaria and/or angioedema in 49 (40.8%), anaphylaxis in 11 (9.2%), severe cutaneous drug reaction in 4 (3.3%), and fixed drug reaction in 1 patient (0.83%). The most frequently suspected agent was cefixime in 41 patients (34.2%). In total, 30 (25%) patients were diagnosed as having cephalosporin hypersensitivity. Confirmation of HRs was also significantly more frequent among patients who were older (p: 0.000), who had taken the drug parenterally (p: 0.000) and with immediate reactions (p: 0.000).

CONCLUSION

Cephalosporin allergy has been confirmed in approximately one-fourth of the patients evaluated for suspected cephalosporin allergy. Confirmation of HRs was significantly more common among patients who were older, had immediate reactions, and had taken the drug parenterally.

Direct oral provocation tests in non-immediate mild cutaneous reactions related to beta-lactam antibiotics

BACKGROUND

Skin testing has a limited role in the diagnosis of non-immediate beta-lactam hypersensitivity in children. The aim of this study was to report the results of oral provocation tests performed without skin tests in children with non-immediate mild cutaneous reactions without systemic symptoms caused by beta-lactam antibiotics.

METHODS

Oral provocation tests with suspected antibiotics were performed to patients with non-immediate mild cutaneous reactions without systemic symptoms caused by beta-lactam antibiotics. Skin tests were not performed before provocation tests. A total of five doses were administered with half-an-hour intervals in increasing doses. Provocation was continued for 5 days.

RESULTS

A total of 119 patients with a median age of 4.3 (IQR: 2-7.5) years, of whom 58% were males, were included in the study. Amoxicillin-clavulanic acid was the most frequently responsible agent in 87 (73.1%) patients, and most common type of rash was maculopapular in 74 (62.2%) patients. Four patients (3.4%) had an urticarial reaction during the provocation test.

CONCLUSION

We did not experience any severe reactions during oral provocation test without previous skin tests performed to children with non-immediate mild cutaneous reactions without systemic symptoms. Omitting skin tests before oral provocation test in this group of children can help decreasing the burden of allergy clinics and alleviating the discomfort of children.

Actual drug allergy during childhood: Five years' experience at a tertiary referral centre

BACKGROUND

Drug hypersensitivity reactions (DHR) are common in the paediatric population, representing a public health problem. Recent studies have confirmed that the frequency of drug allergy is overestimated by both parents and physicians. The aim of this study is to determine the prevalence and risk factors of actual drug allergies in children admitted to a tertiary referral allergy centre.

METHODS

Medical records covering the period of 2005-2010 of children with a history of DHR were reviewed. Demographic features of the patients and results of skin and drug provocation tests were noted. The European Network for Drug Allergy (ENDA) questionnaire was filled by using medical records and making phone calls with parents.

RESULTS

Ninety-six patients with 140 DHRs were evaluated. Seventeen children had confirmed drug allergy by positive skin tests (n=11) and drug provocation tests (n=5). One patient underwent severe anaphylaxis and subsequent cardiac arrest during infusion of the drug, and therefore diagnostic tests were not performed. Actual drug allergy was more frequent in children with chronic diseases (58.8% vs. 26.5%, p=0.018) and histories of anaphylaxis during DHR (58.8% vs. 24%, p=0.001). The patients' history of anaphylaxis [OR: 5.789, 95%CI: 1.880-17.554, p=0.002], sweating [OR: 7.8, 95%CI: 1.041-58.443, p=0.046] and dyspnoea [OR: 5.230, 95%CI: 1.836-14.894, p=0.002] during suspicious DHRs increased the risk for actual drug allergy.

CONCLUSION

Actual drug allergy was determined in 17.7% of the patients with a suspicious DHR. Having a history of anaphylaxis during suspected drug reactions as well as symptoms of sweating and dyspnoea increased the risk for actual drug allergy.

The role of lysine(100) in the binding of acetylcoenzyme A to human arylamine N-acetyltransferase 1: implications for other acetyltransferases

The arylamine N-acetyltransferases (NATs) catalyze the acetylation of aromatic and heterocyclic amines as well as hydrazines. All proteins in this family of enzymes utilize acetyl coenzyme A (AcCoA) as an acetyl donor, which initially binds to the enzyme and transfers an acetyl group to an active site cysteine. Here, we have investigated the role of a highly conserved amino acid (Lys(100)) in the enzymatic activity of human NAT1. Mutation of Lys(100) to either a glutamine or a leucine significantly increased the Ka for AcCoA without changing the Kb for the acetyl acceptor p-aminobenzoic acid. In addition, substrate inhibition was more marked with the mutant enzymes. Steady state kinetic analyzes suggested that mutation of Lys(100) to either leucine or glutamine resulted in a less stable enzyme-cofactor complex, which was not seen with a positively charged arginine at this position. When p-nitrophenylacetate was used as acetyl donor, no differences were seen between the wild-type and mutant enzymes because p-nitrophenylacetate is too small to interact with Lys(100) when bound to the active site. Using 3'-dephospho-AcCoA as the acetyl donor, kinetic data confirmed that Ly(100) interacts with the 3'-phosphoanion to stabilize the enzyme-cofactor complex. Mutation of Lys(100) decreases the affinity of AcCoA for the protein and increases the rate of CoA release. Crystal structures of several other unrelated acetyltransferases show a lysine or arginine residue within 3Å of the 3'-phosphoanion of AcCoA, suggesting that this mechanism for stabilizing the complex by the formation of a salt bridge may be widely applicable in nature.

Amoxicillin allergy in children: five-day drug provocation test in the diagnosis of nonimmediate reactions

BACKGROUND

The drug provocation test (DPT) is the gold standard to rule out drug hypersensitivity. There are standardized DPT protocols to diagnose immediate reactions to drugs, but not for nonimmediate reactions.

OBJECTIVE

The aim of this study was to show the sensitivity and specificity of an allergy work-up that included a 5-day DPT in children with histories of nonimmediate reactions to amoxicillin through focusing on a pediatric population with histories of immediate and nonimmediate reactions to amoxicillin.

METHODS

Two hundred consecutive patients with histories of amoxicillin reactions referred to the Allergy Unit of Anna Meyer Children's Hospital for suspected drug allergy from 2008 to 2011 underwent in vivo tests with the culprit drug according to European Academy of Allergy and Clinical Immunology guidelines. Moreover, most of those children, regardless of the skin tests results, were challenged with amoxicillin for a total of 5 days.

RESULTS

In 4 years, 200 patients were evaluated for a history of drug hypersensitivity to amoxicillin. The majority of patients (76%) had a history of mild nonimmediate reactions. All 200 patients underwent skin tests, and 9 of 200 tested positive. A total of 177 DPTs were performed with amoxicillin for 5 days in each child. Diagnosis of amoxicillin allergy was confirmed by a DPT in 17 patients (9.6%); 14/17 had history of nonimmediate reactions; 4/14 (26.6%) reacted on day 5.

CONCLUSION

According to our results, a long-term DPT protocol increases the sensitivity of the allergy work-up, and it should be recommended for patients with a history of amoxicillin nonimmediate reaction.

Diagnostic evaluation of hypersensitivity reactions to beta-lactam antibiotics in a large population of children

INTRODUCTION

Hypersensitivity reactions to beta-lactams (BLs) are often reported in children, with amoxicillin and, to a lesser extent, cephalosporins being the most frequent drugs involved. Although many of these children are considered to be allergic, a careful evaluation only confirms a low percentage.

OBJECTIVES

To analyse the clinical data, sensitization profile and diagnostic methods used in a large group of children with a clinical history of hypersensitivity reactions to BLs.

METHODS

The study included children aged 1-14 yr with symptoms suggestive of hypersensitivity to BLs from January 2006-December 2012. Diagnosis was confirmed from a clinical history, specific IgE determination, skin testing and, if necessary, a drug provocation test (DPT).

RESULTS

Of a total of 783 patients studied, only 62 (7.92%) were confirmed as being allergic, 9 (14.52%) with immediate and 53 (85.48%) with non-immediate reactions. In those with immediate reactions, 2 (22.22%) were diagnosed by in vitro test, 2 (22.22%) by skin testing and 5 (55.56%) by DPT; in those with non-immediate reactions, 2 (3.77%) were diagnosed by skin testing and 51 (96.23%) by DPT. In all cases, DPT was positive to the culprit drug (29 AX-CLV, 26 AX, 1 cefixime and 1 cefaclor), and the most usual symptoms were exanthema in 43 cases, urticaria in 12, urticaria-angio-oedema in 1 and erythema in 1 case.

CONCLUSION

After an allergological work-up, over 90% of the children evaluated were finally confirmed as tolerant to BLs. Most reactions were of the non-immediate type, and DPT was an essential tool for diagnosis.

[Allergies to antibiotic drugs: their importance in otorhinolaryngology]

BACKGROUND

In 2009, over 40 million prescriptions for antibiotic drugs were counted in outpatient medical care in Germany. This represents a turnover of more than 750 million euros. With over 80 million daily defined doses (DDD), amoxicillin was the most frequently prescribed antibiotic in Germany in 2008. Given the average of 5775 DDD per doctor, otolaryngologists prescribed more antibiotics than specialists in any other field of medicine in 2008; approximately 82% of these were β-lactams and tetracyclines.

MATERIAL AND METHODS

This article is based on selective literature-based research using the PubMed database. The keywords used in the search were:"allergy","anaphylaxis" and"hypersensitivity", in combination with "penicillin","cephalosporin","carbapenem","cotrimoxazole","macrolide","aztreonam" and"tetracycline".

RESULTS

Allergic reactions to antibiotics are among the most frequently reported adverse side effects arising from drug treatment. However, non-allergic adverse side effects owing to drug intolerance are also very common and may be clinically indistinguishable from allergic reactions. Owing to a frequent lack of appropriate diagnostic investigation, the decision to withhold effective standard treatments from patients is often based solely upon anamnestic observations. Up to 10% of respondents in an unselected population report an allergy to penicillin. In 80% of these cases, however, no penicillin-specific IgE-antibodies can be detected.

CONCLUSION

A detailed understanding of the symptoms, diagnostic options and possible cross reactions pertaining to allergic reactions to antibiotics, as well to non-allergic adverse side effects with similar clinical appearance, is very important for otolaryngologists. This profound knowledge ensures that the correct diagnostic steps are taken and that appropriate treatment decisions prevent the unnecessary use of reserve antibiotics.

Prevalence of confirmed immediate type drug hypersensitivity reactions among school children

BACKGROUND

Despite drug-related hypersensitivity reactions are an important health problem, epidemiologic data on drug allergy and hypersensitivity are limited, and studies including diagnostic work-up are scarce. The aim of this study was to determine the actual frequency of immediate type drug hypersensitivity using diagnostic tests in school children with parent-reported drug allergies.

METHODS

This study involved three phases. The first phase is a survey of children with a mean age of 12.9 yrs attending grades 6-8 of primary schools with a questionnaire asking drug-related symptoms within 2 h of ingestion. The total population of sixth to eight grade school children was 210,000, and a sample size of 9096 was deemed to be representative of Ankara [(p) = 1.0%, α < 0.05, β = 0.8, (d) = 0.2.] During the second phase, a detailed clinical history was obtained by phone from the parents of children who had positive parent-reported drug allergy. The final stage of the study consisted of a detailed diagnostic work-up of children with a clinical history consistent with immediate type drug hypersensitivity reaction.

RESULTS

Overall, 11,233 questionnaires were distributed, 10,096 of which were retrieved after completion by parents. The rate of parent-reported immediate type drug hypersensitivity was 7.87% (792 children). However, phone survey revealed a clinical history suggestive of drug allergy in only 117 children (1.16%). After further diagnostic work-up, the true frequency of immediate type drug hypersensitivity was 0.11%.

CONCLUSION

Our results suggest that a positive clinical history is not enough to make a diagnosis of drug allergy, which highlights the significance of undertaking further diagnostic evaluation.

The role of penicillin in benign skin rashes in childhood: a prospective study based on drug rechallenge

Background

Delayed-onset urticarial or maculopapular rashes are frequently observed in children treated with β-lactams. Many are labeled “allergic” without reliable testing.

Objective

Determine the etiology of these rashes by exploring both infectious and allergic causes.

Methods

Children presenting to the emergency department with delayed-onset urticarial or maculopapular rashes were enrolled. Acute and convalescent sera were obtained for viral screening along with a throat swab. Subjects underwent intradermal and patch skin testing for β-lactams 2 months after presentation. Anti–β-lactam blood allergy tests were also obtained. All subjects underwent an oral challenge test (OCT) with the culprit antibiotic.

Results

Eighty-eight children were enrolled between 2006 and 2008. There were 11 (12.5%) positive intradermal and no positive patch tests. There were 2 (2.3%) positive blood allergy tests. There were 6 (6.8%) subjects with a positive OCT, 2 were intradermal-negative, and 4 were intradermal-positive. No OCT reactions were more severe than the index event. Most subjects had at least 1 positive viral study, 54 (65.9%) in the OCT negative group.

Conclusion

In this situation, β-lactam allergy is clearly overdiagnosed because the skin rash is only rarely reproducible (6.8%) by a subsequent challenge. Viral infections may be an important factor in many of these rashes. OCTs were positive in a minority of intradermal skin test–positive subjects. Patch testing and blood allergy testing provided no useful information. OCTs should be considered in all children who develop a delayed-onset urticarial or maculopapular rash during treatment with a β-lactam.

Diagnosis of nonimmediate reactions to beta-lactam antibiotics

Nonimmediate manifestations (i.e. occurring more than 1 h after drug administration), particularly maculopapular and urticarial eruptions, are common during beta-lactam treatment. The mechanisms involved in most nonimmediate reactions seem to be heterogeneous and are not yet completely understood. However, clinical and immunohistological studies, as well as analysis of drug-specific T-cell clones obtained from the circulating blood and the skin, suggest that a type-IV (cell-mediated) pathogenic mechanism may be involved in some nonimmediate reactions such as maculopapular or bullous rashes and acute generalized exanthematous pustulosis. In the diagnostic work-up, the patient's history is fundamental; patch testing is useful, together with delayed-reading intradermal testing. The latter appears to be somewhat more sensitive than patch testing, but also less specific. In case of negative allergologic tests, consideration should be given to provocation tests, and the careful administration of the suspect agents. With regard to in vitro tests, the lymphocyte transformation test may contribute to the identification of the responsible drug. Under the aegis of the European Academy of Allergology and Clinical Immunology (EAACI) interest group on drug hypersensitivity and the European Network for Drug Allergy (ENDA), in this review we describe the general guidelines for evaluating subjects with nonimmediate reactions to beta-lactams.