Multidisciplinary Decision-Making-ITAlian Consensus After Two Years of Real Practice on the Management of Severe Uncontrolled CRSwNP by Biologics (ITACA Study).

PURPOSE OF REVIEW: We aimed to reach an Italian multidisciplinary consensus on some crucial aspects of treatment decision making in CRSwNP, following 2 years of clinical experience in order to support specialists in the management of CRSwNP in clinical practice. We addressed issues relating to therapeutic decision-making and shared criteria for the treatment choice, as well as appropriate timing and criteria for evaluating treatment response, and highlighted the need for repeated multidisciplinary assessments. RECENT FINDINGS: A national survey has been conducted recently to understand how rhinology practice has changed in Italy with the advent of biologics and how this affects patients with uncontrolled, severe CRSwNP. Despite the many published consensus documents, practical recommendations, and protocols on the use of biologics in CRSwNP, heterogenous behaviors in practice are still observed mainly conditioned by the novelty of the topic. The consensus procedure followed a modified Delphi approach. The scientific board included 18 otorhinolaryngologists and 8 allergists, who selected the 4 main topics to be addressed and developed overall 20 statements. Consensus on these statements was sought by a larger group of 48 additional experts, through two rounds of voting, the first web-based, the second in presence with discussion and possible refinement of the statements. The statements reaching an average score ≥ 7 at the second voting round were approved. Five statements were proposed for each of the following topics: baseline evaluation of patients eligible for biologic therapy; choice between different therapeutic options; assessment of the response to biologic treatment; multidisciplinary management. At the first voting round, 19 out of the 20 statements reached a mean score ≥ 7. Following the discussion and a few consequent amendments, at the second round of voting all the 20 statements were approved.

The New Paradigm: The Role of Proteins and Triggers in the Evolution of Allergic Asthma.

Epithelial barrier damage plays a central role in the development and maintenance of allergic inflammation. Rises in the epithelial barrier permeability of airways alter tissue homeostasis and allow the penetration of allergens and other external agents. Different factors contribute to barrier impairment, such as eosinophilic infiltration and allergen protease action-eosinophilic cationic proteins' effects and allergens' proteolytic activity both contribute significantly to epithelial damage. In the airways, allergen proteases degrade the epithelial junctional proteins, allowing allergen penetration and its uptake by dendritic cells. This increase in allergen-immune system interaction induces the release of alarmins and the activation of type 2 inflammatory pathways, causing or worsening the main symptoms at the skin, bowel, and respiratory levels. We aim to highlight the molecular mechanisms underlying allergenic protease-induced epithelial barrier damage and the role of immune response in allergic asthma onset, maintenance, and progression. Moreover, we will explore potential clinical and radiological biomarkers of airway remodeling in allergic asthma patients.

Long-term effectiveness of benralizumab in severe eosinophilic asthma patients treated for 96-weeks: data from the ANANKE study.

BACKGROUND: The efficacy of benralizumab has been broadly demonstrated in severe eosinophilic asthma (SEA), but only few real-life studies evaluated its long-term effects. Here we present novel data from the ANANKE study in which a large cohort of SEA patients was treated for up to 96 weeks. METHODS: ANANKE (NCT04272463) is an observational retrospective Italian study investigating the key characteristics of SEA patients (collected during the 12 months prior to benralizumab initiation) and the clinical outcomes during benralizumab treatment (annual exacerbation rate [AER], lung function, asthma control, OCS use, healthcare resource utilization). A post hoc analysis was also conducted in groups of patients based on history of previous biologic therapy (bio-experienced versus naïve patients). Analyses were descriptive only. RESULTS: Before benralizumab initiation, evaluable SEA patients (N = 162, 61.1% females, mean age 56.0 ± 12.7) showed a median blood eosinophil count (BEC) of 600 cells/mm3 (IQR: 430-890). Patients experienced frequent exacerbations (annualized exacerbation rate [AER]: 4.10, severe AER: 0.98), with impaired lung function and poor asthma control (median ACT score: 14) despite 25.3% reported oral corticosteroid (OCS) use. Nasal polyposis was present in 53.1% patients; 47.5% patients were atopic. After 96 weeks since the start of benralizumab, nearly 90% patients were still on treatment; benralizumab dramatically decreased exacerbations (AER: - 94.9%; severe AER: - 96.9%), improved respiratory parameters (median increase in pre-bronchodilator forced expiratory volume [pre-BD FEV1]: + 400 mL) and asthma control (median ACT score: 23) while eliminating OCS in 60% patients. Importantly, benralizumab effects were either maintained or progressively improved over time, accompanied by a nearly complete depletion of BEC. Benralizumab reduced AER both in naïve (any AER: - 95.9%; severe AER: - 97.5%) and bio-experienced patients (any AER: - 92.4%; severe AER: - 94.0%). CONCLUSIONS: Profound and sustained improvements in all asthma outcomes were observed with benralizumab. The correct identification of patients' eosinophilic-driven asthma phenotype was essential to ensure the achievement of such remarkable results. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04272463.

Different aspects of severe asthma in real life: Role of Staphylococcus aureus enterotoxins and correlation to comorbidities and disease severity.

BACKGROUND: Asthma, with several phenotypes and endotypes, is considered particularly suited for precision medicine. The identification of different non-invasive biomarkers may facilitate diagnosis and treatment. Recently, Staphylococcus aureus and its enterotoxins (SE) have been found to have a role in inducing persistent type 2 airway inflammation in severe asthma, but also in such comorbidities as chronic rhinosinusitis with nasal polyposis (CRSwNP). METHODS: The aim of this retrospective study was to evaluate the prevalence of SE-IgE sensitization in a multicentric Italian cohort of severe asthmatic patients and correlate it with demographic and clinical characteristics. RESULTS: A total of 249 patients were included in the analysis, out of which 25.3% were staphylococcal enterotoxin B (SEB)-IgE positive. We found a meaningful association between SEB-IgE and female gender, a positive association was also measured between CRS and CRSwNP. No significant association was found between SEB-IgE sensitization and atopy, the occurrence of exacerbations and corticosteroid dosages. In the SEB-IgE-positive patient, blood eosinophil count does not appear to be correlated with the severity of the disease. Patients with SEB-IgE sensitization are, on average, younger and with an earlier disease onset, thus confirming the possibility to consider SEB-IgE sensitization as an independent risk factor for developing asthma. CONCLUSIONS: Our data confirm that the search for SE in the initial screening phase of these patients is helpful to better phenotype them, may predict the evolution of comorbidities and lead to a targeted therapeutic choice; in this point of view this represents a goal of precision medicine.

Switching Biological Therapies in Severe Asthma.

Currently, three classes of monoclonal antibodies targeting type 2 inflammation pathways are available in Italy for the treatment of severe asthma: anti-IgE (Omalizumab), anti-IL-5/anti-IL-5Rα (Mepolizumab and Benralizumab), and anti-IL-4Rα (Dupilumab). Numerous randomized controlled trials (RCTs) and real-life studies have been conducted to define their efficacy and identify baseline patients' characteristics potentially predictive of favorable outcomes. Switching to another monoclonal antibody is recommended in case of a lack of benefits. The aim of this work is to review the current knowledge on the impact of switching biological therapies in severe asthma as well as on predictors of treatment response or failure. Almost all of the information about switching from a previous monoclonal antibody to another comes from a real-life setting. In the available studies, the most frequent initial biologic was Omalizumab and patients who were switched because of suboptimal control with a previous biologic therapy were more likely to have a higher baseline blood eosinophil count and exacerbation rate despite OCS dependence. The choice of the most suitable treatment may be guided by the patient's clinical history, biomarkers of endotype (mainly blood eosinophils and FeNO), and comorbidities (especially nasal polyposis). Due to overlapping eligibility, larger investigations characterizing the clinical profile of patients benefiting from switching to different monoclonal antibodies are needed.

ChAracterization of ItaliaN severe uncontrolled Asthmatic patieNts Key features when receiving Benralizumab in a real-life setting: the observational rEtrospective ANANKE study.

BACKGROUND: Data from phase 3 trials have demonstrated the efficacy and safety of benralizumab in patients with severe eosinophilic asthma (SEA). We conducted a real-world study examining the baseline characteristics of a large SEA population treated with benralizumab in clinical practice and assessed therapy effectiveness. METHODS: ANANKE is an Italian multi-center, retrospective cohort study including consecutive SEA patients who had started benralizumab therapy ≥ 3 months before enrolment (between December 2019 and July 2020), in a real-world setting. Data collection covered (1) key patient features at baseline, including blood eosinophil count (BEC), number and severity of exacerbations and oral corticosteroid (OCS) use; (2) clinical outcomes during benralizumab therapy. We also conducted two post-hoc analyses in patients grouped by body mass index and allergic status. Analyses were descriptive only. RESULTS: Of 218 patients with SEA enrolled in 21 Centers, 205 were evaluable (mean age, 55.8 ± 13.3 years, 61.5% females). At treatment start, the median BEC was 580 cells/mm3 (interquartile range [IQR]: 400-850); all patients were on high-dose inhaled controller therapy and 25.9% were on chronic OCS (median dose: 10 mg/die prednisone-equivalent [IQR: 5-25]); 92.9% experienced ≥ 1 exacerbation within the past 12 months (annualized exacerbation rate [AER] 4.03) and 40.3% reported ≥ 1 severe exacerbation (AER 1.10). During treatment (median duration: 9.8 months [IQR 6.1-13.9]; ≥ 12 months for 34.2% of patients), complete eosinophil depletion was observed; exacerbation-free patients increased to 81% and only 24.3% reported ≥ 1 severe event. AER decreased markedly to 0.27 for exacerbations of any severity (- 93.3%) and to 0.06 for severe exacerbations (- 94.5%). OCS therapy was interrupted in 43.2% of cases and the dose reduced by 56% (median: 4.4 mg/die prednisone-equivalent [IQR: 0.0-10.0]). Lung function and asthma control also improved. The effectiveness of benralizumab was independent of allergic status and body mass index. CONCLUSIONS: We described the set of characteristics of a large cohort of patients with uncontrolled SEA receiving benralizumab in clinical practice, with a dramatic reduction in exacerbations and significant sparing of OCS. These findings support benralizumab as a key phenotype-specific therapeutic strategy that could help physicians in decision-making when prescribing biologics in patients with SEA. Trial registration ClinicalTrials.gov Identifier: NCT04272463.

EAACI position paper on the clinical use of the bronchial allergen challenge: Unmet needs and research priorities.

Allergic asthma (AA) is a common asthma phenotype, and its diagnosis requires both the demonstration of IgE-sensitization to aeroallergens and the causative role of this sensitization as a major driver of asthma symptoms. Therefore, a bronchial allergen challenge (BAC) would be occasionally required to identify AA patients among atopic asthmatics. Nevertheless, BAC is usually considered a research tool only, with existing protocols being tailored to mild asthmatics and research needs (eg long washout period for inhaled corticosteroids). Consequently, existing BAC protocols are not designed to be performed in moderate-to-severe asthmatics or in clinical practice. The correct diagnosis of AA might help select patients for immunomodulatory therapies. Allergen sublingual immunotherapy is now registered and recommended for controlled or partially controlled patients with house dust mite-driven AA and with FEV1 ≥ 70%. Allergen avoidance is costly and difficult to implement for the management of AA, so the proper selection of patients is also beneficial. In this position paper, the EAACI Task Force proposes a methodology for clinical BAC that would need to be validated in future studies. The clinical implementation of BAC could ultimately translate into a better phenotyping of asthmatics in real life, and into a more accurate selection of patients for long-term and costly management pathways.

Therapeutic Impact and Management of Persistent Head and Neck Atopic Dermatitis in Dupilumab-Treated Patients.

BACKGROUND: Localization of atopic dermatitis (AD) in exposed areas such as the hands, head, and neck has been considered as a negative factor impacting on dupilumab response, although a comparison of exposed versus unexposed areas is not currently available. OBJECTIVES: The aim of this study is to evaluate the clinical response to dupilumab depending on the presence or persistency of AD skin manifestations in specific body areas. METHODS: The study retrospectively collected clinical and demographic data of adult patients affected by moderate to severe AD. Based on the anatomical sites involved, 5 subcohorts of patients were identified. RESULTS: A total of 41 patients were included in the study. Disease amelioration was detected during the study period, although baseline head/neck and hand localization was associated with a significantly lower likelihood of achieving an Eczema Area Severity Index (EASI) ≤1. In addition, patients with head/neck persistency showed a significantly lower response when compared to patients without persistency of head/neck AD in terms of both mean EASI and Dermatology Life Quality Index (DLQI) reduction. CONCLUSION: AD localization in exposed areas at the baseline and AD persistency at the head/neck may have a negative impact on certain treatment response parameters to dupilumab therapy.

Effectiveness and safety of dupilumab in patients with chronic rhinosinusitis with nasal polyps and associated comorbidities: a multicentric prospective study in real life.

BACKGROUND: Biologics are currently one of the main treatment options for a number of diseases. The IgG4 monoclonal antibody dupilumab targets the Interleukin-4 receptor alpha chain, thus preventing the biological effects of the cytokines IL-4 and IL-13, that are essential for the Th2 response. Several controlled trials showed that dupilumab is effective and safe in patients with atopic dermatitis (AD), severe asthma and chronic rhinosinusitis with nasal polyps (CRSwNP), thus resulting in approval by regulatory agencies. Aim of the study was to evaluate the efficacy and safety of dupilumab in adult patients with CRSwNP stratified by common overlapping comorbid conditions. METHODS: We performed a multicenter, observational, prospective study enrolling adult patients with severe CRSwNP who had started dupilumab treatment in the context of standard care from January 2021 to October 2021. Data were collected from twentynine Italian secondary care centers for allergy and clinical immunology, all of which were part of the Italian Society of Allergy, Asthma and Clinical Immunology (SIAAIC). A number of efficacy parameters were used. Patient data were compared using the Wilcoxon test for paired data. All statistical analyses were performed with SPSS version 20 (IBM, Armonk, NY, USA). RESULTS: In total, 82 patients with nasal polyposis were identified. A significant improvement was detected for all the applied efficacy parameters, i.e. 22-item Sino-Nasal Outcome Test (SNOT-22) and bilateral endoscopic nasal polyp score (NPS) scores for CRSwNP, Rhinitis Control Scoring System (RCSS) and Rhinoconjunctivitis Quality of Life Questionnaire (RQLQ) scores for allergic perennial rhinitis, Forced Expiratory Volume in the 1st second (FEV1) and Asthma Quality of Life Questionnaire (AQLQ) scores for asthma, Eczema Area and Severity Index (EASI) and Dermatology Life Quality Index (DLQI) scores for AD. A non-significant improvement was also obtained in the Urticaria Activity Score over 7 days (UAS7) for chronic spontaneous urticaria. Treatment with dupilumab was well tolerated. CONCLUSIONS: These data suggest that dupilumab treatment in patients suffering from CRSwNP and associated comorbidities may be suitable. Such outcome, although confirmation by trials is warranted, suggests the possibility to treat different disorders with a single therapy, with favorable effects especially under the cost-effectiveness aspect.

Beta-lactam-induced immediate hypersensitivity reactions: A genome-wide association study of a deeply phenotyped cohort.

BACKGROUND: ß-lactam antibiotics are associated with a variety of immune-mediated or hypersensitivity reactions, including immediate (type I) reactions mediated by antigen-specific IgE. OBJECTIVE: We sought to identify genetic predisposing factors for immediate reactions to ß-lactam antibiotics. METHODS: Patients with a clinical history of immediate hypersensitivity reactions to either penicillins or cephalosporins, which were immunologically confirmed, were recruited from allergy clinics. A genome-wide association study was conducted on 662 patients (the discovery cohort) with a diagnosis of immediate hypersensitivity and the main finding was replicated in a cohort of 98 Spanish cases, recruited using the same diagnostic criteria as the discovery cohort. RESULTS: Genome-wide association study identified rs71542416 within the Class II HLA region as the top hit (P = 2 × 10-14); this was in linkage disequilibrium with HLA-DRB1∗10:01 (odds ratio, 2.93; P = 5.4 × 10-7) and HLA-DQA1∗01:05 (odds ratio, 2.93, P = 5.4 × 10-7). Haplotype analysis identified that HLA-DRB1∗10:01 was a risk factor even without the HLA-DQA1∗01:05 allele. The association with HLA-DRB1∗10:01 was replicated in another cohort, with the meta-analysis of the discovery and replication cohorts showing that HLA-DRB1∗10:01 increased the risk of immediate hypersensitivity at a genome-wide level (odds ratio, 2.96; P = 4.1 × 10-9). No association with HLA-DRB1∗10:01 was identified in 268 patients with delayed hypersensitivity reactions to ß-lactams. CONCLUSIONS: HLA-DRB1∗10:01 predisposed to immediate hypersensitivity reactions to penicillins. Further work to identify other predisposing HLA and non-HLA loci is required.

Detection of Serum-Specific IgE by Fluoro-Enzyme Immunoassay for Diagnosing Type I Hypersensitivity Reactions to Penicillins.

Diagnosis of type I hypersensitivity reactions (IgE-mediated reactions) to penicillins is based on clinical history, skin tests (STs), and drug provocation tests (DPTs). Among in vitro complementary tests, the fluoro-enzyme immunoassay (FEIA) ImmunoCAP® (Thermo-Fisher, Waltham, MA, USA) is the most widely used commercial method for detecting drug-specific IgE (sIgE). In this study, we aimed to analyze the utility of ImmunoCAP® for detecting sIgE to penicillin G (PG) and amoxicillin (AX) in patients with confirmed penicillin allergy. The study includes 139 and 250 patients evaluated in Spain and Italy, respectively. All had experienced type I hypersensitivity reactions to penicillins confirmed by positive STs. Additionally, selective or cross-reactive reactions were confirmed by DPTs in a subgroup of patients for further analysis. Positive ImmunoCAP® results were 39.6% for PG and/or AX in Spanish subjects and 52.4% in Italian subjects. When only PG or AX sIgE where analyzed, the percentages were 15.1% and 30.4%, respectively, in Spanish patients; and 38.9% and 46% in Italian ones. The analysis of positive STs showed a statistically significant higher percentage of positive STs to PG determinants in Italian patients. False-positive results to PG (16%) were detected in selective AX patients with confirmed PG tolerance. Low and variable sensitivity values observed in a well-defined population with confirmed allergy diagnosis, as well as false-positive results to PG, suggest that ImmunoCAP® is a diagnostic tool with relevant limitations in the evaluation of subjects with type I hypersensitivity reactions to penicillins.

Real-life impact of COVID-19 pandemic lockdown on the management of pediatric and adult asthma: A survey by the EAACI Asthma Section.

BACKGROUND: The restrictions imposed by the COVID-19 pandemic impact heavily the management of chronic diseases like asthma. This study aimed to evaluate the management of adults and children with asthma during COVID-19-related lockdown. METHODS: A survey was launched by the European Academy of Allergy and Clinical Immunology (EAACI) via e-mail, website, and social media to EAACI members and members of peer societies. RESULTS: The survey was completed by 339 healthcare professionals from 52 countries. 79% of follow-up consultations were replaced by phone calls, whereas 49% of newly referred patients attended the clinic. 62%, 76%, 66%, 76%, and 87% of responders did not conduct spirometry, impulse oscillometry, bronchodilator test, FeNO, or methacholine provocation, respectively, for asthma diagnosis in adults. The numbers were similar for children. 73% of responders based the initial asthma diagnosis and the prescription of inhaled therapy on clinical parameters only. Lung function tests were used in 29% of cases to monitor asthma worsening, and only 56% of participants were recommended to their patients ambulatory peak expiratory flow (PEF) measurements. Using a 1 (not at all) to 5 (very much) scale, the responders considered that the quality of healthcare provided and the patients' asthma status had deteriorated during the lockdown with 3.2 points and 2.8 points, respectively. CONCLUSION: Collectively, these results suggest that all necessary resources should be allocated to ensure the performance of lung function tests for initial diagnosis, whereas digital remote monitoring should be reinforced for the follow-up of children and adults with asthma.

Analysis of the drop-out rate in patients receiving mepolizumab for severe asthma in real life.

Mepolizumab (anti IL-5, monoclonal antibody) is commercially available in Italy since more than one year for the treatment of severe hypereosinophilic asthma. Its efficacy and safety were evaluated in several regulatory trials. The characteristics of this drug in real life began to be assessed only recently. We describe herein the drop-out rate observed with mepolizumab in real life, because this datum can indirectly reflect the safety and tolerability aspects. The demographic and clinical data of patients receiving mepolizumab for severe asthma were collected, and the number and reasons for discontinuation of the treatment were analyzed. The database involves 143 patients (67 male, age range 19-80 year) who received at least one dose of mepolizumab. The observed discontinuation rate was 6/143 (4.2%). Five out of 6 discontinuations were due to lack of response, and one was an adverse event (urticaria) probably related to the treatment. There was no clinical difference between the drop-out group and the patients still ongoing. As compared to the clinical trials published the discontinuation rate was lower in our population, especially for adverse events (7% vs 23.7%). Thus, the tolerability of mepolizumab, as derived from discontinuations, seems to be better in real-life than in clinical trials.

One year of mepolizumab. Efficacy and safety in real-life in Italy.

BACKGROUND: Severe asthma is a disease with a heavy socio-economic burden and a relevant impact on the life of patients. Mepolizumab (MEP) was recently introduced in practice. The previous data were favourable as efficacy and safety are concerned. Nowadays, we can report the clinical data after more than one year of use of MEP in the real-life setting. OBJECTIVE: To evaluate the efficacy and safety of MEP in a real life framework, mainly concerning asthma exacerbations, steroid dependence, effects on respiratory function and adverse events. METHODS: This retrospective analysis was performed on 138 patients, treated with MEP for at least 12 months, and referred to eleven severe asthma clinics in Italy. All patients met the criteria for severe uncontrolled asthma according to ATS/ERS guidelines and prescribing MEP conditions according to the Italian Drug Agency (AIFA). RESULTS: We could observe 138 patients (78 female, age 58 ±â€¯10 years). The average age of onset of asthma was 34 ±â€¯16 years. The blood eosinophil count decreased from 822 ±â€¯491/µL at baseline to 117 ±â€¯96/µL (p < .0001) after 12 months of therapy. Exacerbations decreased from 3.8/year to 0.7/year (-81%; p < .0001). Steroid-dependent patients before MEP (80%) with a daily dose of 10.1 ±â€¯9.4 mg prednisone decrease at 28% after 12 months with a mean of 2.0 ±â€¯4.2 mg/day (p < .0001). The occurrence of adverse events was overall low. CONCLUSIONS & CLINICAL RELEVANCE: In this real-life setting, MEP confirmed its efficacy and safety profile, already shown in clinical trials. This was apparent concerning exacerbation rate, systemic steroids intake and safety.

Non-immediate Cutaneous Reactions to Beta-Lactams: Approach to Diagnosis.

Non-immediate cutaneous reactions (i.e., occurring at least 1 h after the initial drug administration), particularly maculopapular exanthemas and urticarial eruptions, are common during beta-lactam treatments. A T cell-mediated pathogenic mechanism has been demonstrated in some cutaneous reactions, such as maculopapular exanthema, fixed drug eruption, acute generalized exanthematous pustulosis, and drug-induced hypersensitivity syndrome. In the diagnostic work-up, patch testing is useful, together with delayed-reading intradermal testing. Patch tests are a simple and safe diagnostic tool, which in the case of severe reactions should be used as the first line of investigation. However, patch tests are less sensitive than intradermal tests, which are preferable in subjects with mild reactions. Lymphocyte transformation or activation tests and enzyme-linked immunosorbent spot assays can be used as complementary tests. In selected cases of mild or moderate reactions, displaying negative results in the aforesaid allergy tests, a graded challenge with the implicated beta-lactam can be performed.

Cross-reactivity and tolerability of aztreonam and cephalosporins in subjects with a T cell-mediated hypersensitivity to penicillins.

BACKGROUND: The few studies performed in adults with T cell-mediated hypersensitivity to penicillins have found a rate of cross-reactivity with cephalosporins ranging from 2.8% to 31.2% and an absence of cross-reactivity with aztreonam. OBJECTIVE: We sought to evaluate the possibility of using cephalosporins and aztreonam in subjects with documented delayed hypersensitivity to penicillins who especially require them. METHODS: We conducted a prospective study of 214 consecutive subjects who had 307 nonimmediate reactions to penicillins (almost exclusively aminopenicillins) and had positive patch test and/or delayed-reading skin test responses to at least 1 penicillin reagent. To assess cross-reactivity with cephalosporins and aztreonam and the tolerability of such alternative ß-lactams, all subjects underwent skin tests with cephalexin, cefaclor, cefadroxil, cefuroxime, ceftriaxone, and aztreonam. Subjects with negative responses were challenged with the alternative ß-lactams concerned. RESULTS: All subjects had negative skin test results to cefuroxime, ceftriaxone, and aztreonam and tolerated challenges. Forty (18.7%) of the 214 subjects had positive skin test responses to at least 1 aminocephalosporin. Of the 174 subjects with negative responses, 170 underwent challenges; 1 reacted to cefaclor. CONCLUSIONS: These data demonstrate a rate of cross-reactivity between aminopenicillins and aminocephalosporins (ie, cephalexin, cefaclor, and cefadroxil) of around 20%, as well as the absence of cross-reactivity between penicillins and cefuroxime, ceftriaxone, and aztreonam in all subjects with T cell-mediated hypersensitivity to penicillins, almost exclusively aminopenicillins. Therefore these subjects could be treated with cefuroxime, ceftriaxone, and aztreonam. In those who especially require cephalosporin or aztreonam treatment, however, we recommend pretreatment skin tests because negative responses indicate tolerability.

Tolerability of aztreonam and carbapenems in patients with IgE-mediated hypersensitivity to penicillins.

BACKGROUND: Studies performed on samples larger than 100 subjects with a documented IgE-mediated hypersensitivity to penicillins have demonstrated a cross-reactivity rate of approximately 1% between penicillins and both imipenem and meropenem, whereas a single study found a cross-reactivity rate of 6.2% with aztreonam in 16 such subjects. OBJECTIVE: To assess the cross-reactivity and tolerability of aztreonam and 3 carbapenems (imipenem-cilastatin, meropenem, and ertapenem) in patients with documented IgE-mediated hypersensitivity to penicillins. METHODS: A total of 212 consecutive subjects with immediate reactions to penicillins and positive results on skin tests to at least 1 penicillin reagent underwent skin tests with aztreonam and carbapenems; subjects with negative results were challenged with escalating doses of aztreonam and carbapenems. RESULTS: All subjects displayed negative skin test results to both aztreonam and carbapenems; 211 accepted challenges and tolerated them. Challenges were not followed by full therapeutic courses. CONCLUSIONS: These data indicate the tolerability of both aztreonam and carbapenems in penicillin-allergic subjects. In those who especially require these alternative ß-lactams, however, we recommend pretreatment skin tests, both because rare cases of cross-reactivity have been reported and because negative results indicate tolerability.

IgE-mediated hypersensitivity to cephalosporins: Cross-reactivity and tolerability of alternative cephalosporins.

BACKGROUND: Studies regarding the cross-reactivity and tolerability of alternative cephalosporins in large samples of subjects with an IgE-mediated hypersensitivity to cephalosporins are lacking. OBJECTIVE: We sought to evaluate the possibility of using alternative cephalosporins in subjects with cephalosporin allergy who especially require them. METHODS: One hundred two subjects with immediate reactions to cephalosporins and positive skin test results to the responsible drugs underwent serum specific IgE assays with cefaclor and skin tests with different cephalosporins. Subjects were classified in 4 groups: group A, positive responses to 1 or more of ceftriaxone, cefuroxime, cefotaxime, cefepime, cefodizime, and ceftazidime; group B, positive responses to aminocephalosporins; group C, positive responses to cephalosporins other than those belonging to the aforementioned groups; and group D, positive responses to cephalosporins belonging to 2 different groups. Group A subjects underwent challenges with cefaclor, cefazolin, and ceftibuten; group B participants underwent challenges with cefuroxime axetil, ceftriaxone, cefazolin, and ceftibuten; and group C and D subjects underwent challenges with some of the aforementioned cephalosporins selected on the basis of their patterns of positivity. RESULTS: There were 73 subjects in group A, 13 in group B, 7 in group C, and 9 in group D. Challenges with alternative cephalosporins (ceftibuten in 101, cefazolin in 96, cefaclor in 82, and cefuroxime axetil and ceftriaxone in 22 subjects) were well tolerated. CONCLUSIONS: Cephalosporin hypersensitivity does not seem to be a class hypersensitivity. Subjects with cephalosporin allergy who especially require alternative cephalosporins might be treated with compounds that have side-chain determinants different from those of the responsible cephalosporins and have negative pretreatment skin test responses.