Diagnosis Of Penicillin Allergy Research Articles

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

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

Performance Characteristics of Basophil Activation Tests for Diagnosing Penicillin Allergy: A Meta-Analysis

Approximately 10% of the global population identify themselves as penicillin allergic, yet 90% are not truly allergic and could safely tolerate penicillin. There is no simple way to identify these people. Current invitro diagnostics include specific immunoglobulin E (with a sensitivity of 19% and specificity of 97%) and a basophil activation test (BAT) with undefined sensitivity and specificity. To define the sensitivity and specificity of BAT in the diagnosis of penicillin allergy METHODS: We searched PubMed and EMBASE from inception to April 2, 2023, for original studies evaluating the performance characteristics of BAT for penicillin allergy in adults. Study selection, data extraction, risk of bias, assessment with QUADAS-2 tool, certainty assessment with Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) methodology were performed independently, in duplicate. Meta-analysis was performed using Reitsma methodology. Twenty-two studies fulfilled the inclusion criteria. Twelve used the same positive threshold giving a summary point sensitivity 51% (95% confidence interval [95% CI]46%-56%) and specificity 89% (95% CI 85%-93%). Significant risk of bias was identified owing to patient selection. GRADE certainty of evidence rated sensitivity very low due to imprecision and specificity as low. There was great heterogeneity in methods used. Use of 1,000 basophils per test did not improve performance above 500 basophils. BAT sensitivity is highly variable across studies and remains too low to be considered as a routine element of clinical practice. BAT specificity is not as good as specific immunoglobulin E in penicillin allergy diagnosis. Significant further work is required in this field before clinical application of BAT in routine practice.

Safety of Direct Drug Provocation for the Evaluation of Penicillin Allergy in Low-Risk Adults

About 10% of patients have a penicillin allergy label, but less than 5% of them are actually allergic. Unnecessary penicillin avoidance is associated with serious medical consequences. Given the growing number of these labels, it is imperative that our diagnostic strategy for penicillin allergy be as efficient as possible. The validity of traditionally used skin tests (STs) has been questioned, whereas drug provocation testing (DPT), the criterion standard, without previous ST appears very safe in most cases. To evaluate the safety of direct DPT without consideration for ST results and the validity of ST in the diagnosis of penicillin allergy. In this prospective cohort study without a control group, we recruited patients consulting an allergist for penicillin allergy. Patients underwent ST followed by DPT regardless of ST results. Patients with anaphylaxis to penicillin within the past 5 years or a severe delayed reaction were excluded, as were those with significant cardiorespiratory comorbidity. None of the 1002 recruited patients had a serious reaction to DPT. Ten (1.0%) had a mild immediate reaction, of whom only 1 (0.1%) was considered likely IgE-mediated. The positive and negative predictive values of ST for an immediate reaction were 3.6% and 99.1%, respectively. In a low-risk adult population reporting penicillin allergy, ST has very poor positive predictive value. Direct DPT without ST is safe and appears to be an ideal diagnostic strategy to remove penicillin allergy labels that could be implemented in first-line practice.

Drug Allergies in Immunodeficiencies: a Single-Center Experience in Southern California

BackgroundAbout 10% of individuals in the US report penicillin allergy. However, after a complete evaluation, more than 90% of these patients can tolerate penicillin. The label of penicillin allergy has negative health implications including the use of broad spectrum antibiotics, increased healthcare costs, high risk of treatment failure, infectious complications and antimicrobial resistance. Patients with immunodeficiencies develop recurrent and severe infections necessitating frequent use of antibiotics. Data on reported and physician-confirmed drug allergy in patients with immunodeficiency is limited. MethodsA retrospective review of electronic medical records was performed of patients seen in immunology clinic between January 1, 2018 and January 1, 2022. Data collected included demographics, listed drug allergies (along with the documented reaction), comorbidities, immunologic evaluation, current treatments, and past allergy evaluation of drug allergies and confirmed drug allergy diagnosis. ResultsThe mean age was 58 years. There were 327 women and 144 men. The most common immunodeficiency diagnoses were specific antibody deficiency (36.1%), hypogammaglobulinemia (29.9%), common variable immunodeficiency (29.7%), and IgG subclass deficiency (25.9%). Seventy three percent had at least one reported drug allergy and 24.3% had reported penicillin allergy. The most common reported antibiotic allergy was sulfa antibiotics at 30.3%. Mucocutaneous (27%) followed by gastrointestinal (4.6%) symptoms were the most reported penicillin allergy reactions. There was no association between reported penicillin allergy and type of immunodeficiency, serum IgE, IgG, IgA, or IgM levels. Female gender, presence of autoimmunity, and IVIG treatment were associated with reported penicillin allergy. The diagnosis of penicillin allergy was confirmed in only 1 of 19 patients referred for an allergy evaluation. DiscussionIn this study, we observed a higher incidence of penicillin allergy in adult patients with immunodeficiencies than in the general population. The most prevalent antibiotic allergy in this group was sulfa antibiotic allergy. Formal allergy evaluation was conducted on a small subset of patients and showed that the incidence of true penicillin allergy is much lower than reported. This study highlights the importance of an active approach to penicillin allergy de-labeling.

Parent-reported penicillin allergies in children: A qualitative study

BackgroundPenicillin allergies are commonly reported in children. Most reported penicillin allergies are false, resulting in the unnecessary selection of alternative antibiotic treatments that promote antibiotic resistance. While formal allergy testing is encouraged to establish a diagnosis of penicillin allergy, children are rarely referred for allergy testing, and study of parents’ experiences and perceptions of their child's reported penicillin allergy is limited. We aimed to describe parents’ experiences and perceptions of their child's penicillin allergy and attitudes towards penicillin allergy testing to identify opportunities to engage parents in antimicrobial stewardship efforts. MethodsThis was a qualitative descriptive study. ResultsEighteen parents participated in this study. Parents’ children were on average 2 years old when the index reaction occurred, and 7 years had passed since the reaction. Transcripts revealed that participants were receptive to penicillin allergy testing for their child after learning the consequences of penicillin allergy and availability of allergy testing. Four major themes emerged from data (1) parents’ making sense of allergy; (2) parents’ impressions of allergy label, (3) parents’ attitudes towards allergy testing, and (4) parents’ desire to be informed of testing availability. ConclusionsEfforts are needed to engage parents in addressing spuriously reported penicillin allergies.

Penicillin Allergy in Spine Surgery: Increased Rates of Sepsis, Emergency Room Visits, and Readmission

To determine if a penicillin allergy is an independent risk factor for poor outcomes after anterior cervical discectomy and fusion (ACDF) and posterior lumbar fusion (PLF). A retrospective database review was performed using the PearlDiver data set. The study population included all patients younger than 85 years who underwent elective PLF or ACDF with diagnosis of penicillin allergy using International Classification of Diseases codes. Study patients were compared with controls for 90-day complications and 1-year reoperation rates. A multivariate logistic regression was used to determine the independent effect of penicillin allergy on the postoperative outcomes. PLF cohort multivariate analysis showed that patients with a penicillin allergy had a significantly increased risk of sepsis (2.6% vs. 2.0%; P= 0.020), urinary tract infection (10.8% vs. 8.4%; P < 0.001), emergency room visits (27.3% vs. 20.2%; P < 0.001), and readmissions (9.6% vs. 6.4%; P < 0.001) within 90 days index of surgery. Similarly, the ACDF cohort multivariate analysis showed that a penicillin allergy was associated with an increased risk of sepsis (1.8% vs. 1.1%; P < 0.001), emergency room visits (27.2% vs. 20.7%; P < 0.001), and readmissions (6.8% vs. 5.6%; P= 0.003) within 90 days index of surgery. The present study found that a reported penicillin allergy is associated with an increase in sepsis, urinary tract infection, emergency room visit, and readmission postoperatively within 90 days after PLF and ACDF. The findings can help physicians provide patients with more comprehensive preoperative counseling in the setting of patient-reported penicillin allergy.

Management of penicillin allergy in primary care: a qualitative study with patients and primary care physicians

BackgroundSix percent of patients are allergic to penicillin according to their medical records. While this designation protects a small number of truly allergic patients from serious reactions, those who are incorrectly labelled may be denied access to recommended first line treatment for many infections. Removal of incorrect penicillin allergy may have positive health consequences for the individual and the general population.We aimed to explore primary care physicians’ (PCPs) and patients’ views and understanding of penicillin allergy with a focus on clinical management of infections in the face of a penicillin allergy record.MethodsWe conducted an interview study with 31 patients with a penicillin allergy record, and 19 PCPs in the North of England. Data were analysed thematically.ResultsPatients made sense of their allergy status by considering the timing and severity of symptoms. Diagnosis of penicillin allergy was reported to be ‘imperfect’ with PCPs relying on patient reports and incomplete medical records. PCPs and patients often suspected that an allergy record was incorrect, but PCPs were reluctant to change records. PCPs had limited knowledge of allergy services. PCPs often prescribed alternative antibiotics which were easy to identify. Both patients and PCPs differed in the extent to which they were aware of the negative consequences of incorrect penicillin allergy records, their relevance and importance to their lives, and management of penicillin allergy.ConclusionsPCPs and patients appear insufficiently aware of potential harms associated with incorrect penicillin allergy records. Some of the problems experienced by PCPs could be reduced by ensuring the details of newly diagnosed reactions to antibiotics are clearly documented. In order for PCPs to overturn more incorrect penicillin records through appropriate use of allergy services, more information and training about these services will be needed.

Diagnostic value and safety of penicillin skin tests in children with immediate penicillin allergy.

Background: The first-line method in the diagnosis of patients who describe an immediate reaction after penicillin intake is a skin test (ST) with penicillin reagents. Objectives: We aimed to determine the safety and diagnostic value of penicillin STs in the diagnosis of immediate reactions to penicillins in pediatric patients. Methods: The study included pediatric patients with suspected immediate reaction to penicillin who were subjected to STs by using a standard penicillin test kit as well as suspected penicillin and the drug provocation tests (DPT) with the suspected penicillin at our clinic. Results: A total of 191 patients (53.9% boys) with a median age of 6.83 years (interquartile range, 4.2-12 years) were included in the study. The time from drug intake to the onset of reaction was ≤1 hour in 138 patients (72.3%) and 1 to 6 hours in 53 patients (27.7%). Penicillin allergy (PA) was confirmed by diagnostic tests in 36 of the 191 patients (18.8%). In multivariate logistic regression analysis, the history of both urticaria and angioedema (odds ratio [OR] 27.683 [95% confidence interval {CI}, 3.143-243.837]; p = 0.003) and anaphylaxis (OR 56.246 [95% CI, 6.598-479.489]; p < 0.001) were the main predictors of a PA diagnosis. Although ST results were positive in 23 patients (63.8%), 13 patients (26.2%) had positive DPT results despite negative ST results. The negative predictive value (NPV) of STs was calculated 92.2% (155/168). None of our patients experienced immediate or delayed systemic and/or local reactions in relation to the STs. Conclusion: A history of urticaria with angioedema and anaphylaxis were the main predictors of true PA in children with suspected immediate reactions. STs with penicillin reagents are safe for use in children. Although STs have a high NPV, DPT is the gold standard for diagnosis. DPTs should be performed as the final step of the diagnostic evaluation of PA in patients with negative ST results.

Penicillin Allergy Delabeling: A Multidisciplinary Opportunity

The penicillin allergy label has been consistently linked with deleterious effects that span the health care spectrum, including suboptimal clinical outcomes, the emergence of bacterial resistance, and increased health care expenditures. These risks have recently motivated professional organizations and public health institutes to advocate for the implementation of penicillin allergy delabeling initiatives; however, the burden of delabeling millions of patients is too expansive for any one discipline to bear alone. This review presents the unique perspectives and roles of various stakeholder groups involved in penicillin allergy diagnosis, assessment, and delabeling; we emphasize opportunities, barriers, and promising areas of innovation. We summarize penicillin allergy methods and tools that have proven successful in delabeling efforts. A multidisciplinary approach to delabeling patients with reported penicillin allergy, bolstered by evidence-based clinical practices, is recommended to reduce the risks that associate with the penicillin allergy label.

Effect of Penicillin Allergy Diagnosis on Hospital Prescribing

More than 10% of hospitalized patients have reported penicillin allergies, yet fewer than 10% of such patients have penicillin allergies confirmed when

Minimal agreement between basophil activation test and immunoassay in diagnosis of penicillin allergy

IntroductionBasophil activation test (BAT) and immunoassays are the most widely used in vitro tests to diagnose IgE-mediated allergic reactions to penicillin. However, studies to determine if one test is interdependent from another are limited. ObjectiveThe present study aimed to measure the agreement between BAT and immunoassay in diagnosis of penicillin allergy. MethodBAT was performed using penicillin G (Pen G), penicillin V (Pen V), penicilloyl-polylysine (PPL), minor determinant mix (MDM), amoxicillin (Amx) and ampicillin (Amp) in 25 patients. Immunoassay of total IgE (tIgE) and specific IgE (sIgE) antibodies to Pen G, Pen V, Amx and Amp were quantified. Skin prick test (SPT) using PPL-MDM, Amx, Amp and Clavulanic acid were also performed. ResultsMinimal agreement was observed between BAT and immunoassay (k=0.25). Of two BAT-positive patients, one patient is positive to Amx (59.27%, SI=59) and Amp (82.32%, SI=82) but sIgE-negative to all drug tested. This patient is also SPT-positive to both drugs. Another patient is BAT-positive to Pen G (10.18%, SI=40), Pen V (25.07%, SI=100) and Amp (19.52%, SI=79). In sIgE immunoassay, four patients were sIgE-positive to at least one of the drugs tested. The sIgE level of three patients was between low and moderate and they were BAT-negative. One BAT-positive patient had a high level of sIgE antibodies (3.50–17.5kU/L) along with relatively high specific to total IgE ratio ≥0.002 (0.004–0.007). ConclusionsThe agreement between BAT and immunoassay is minimal. Performing both tests provides little increase in the sensitivity of allergy diagnosis work-up for immediate reactions to penicillin.

From the pages of AllergyWatch®

For this issue of From the Pages of Allergy Watch, there are 3 reviews dealing with various aspects of drug allergy, the focus of this month’s Annals. The first review is from a study published in the Annals last year, which examines the safety of direct provocation challenges for patients with a diagnosis of penicillin allergy. The next review discusses the experience of a Danish allergy clinic on testing and challenging patients with a diagnosis of local anesthetic allergy. The last one is a review of data from patients reporting anaphylaxis after omalizumab.

Perioperative Management of the Penicillin-Allergic Patient

AN ESTIMATED 32 MILLION AMERICANS have a documented penicillin allergy in their medical record, which equates to approximately 10% of the population in the United States. 1 Evaluation and diagnosis of penicillin allergy for healthcare professionals: is it really a penicillin allergy. Centers for Disease Control and Prevention, National Center for Emerging and Zoonotic Infectious Diseases (NCEZID), Division of Healthcare Quality Promotion (DHQP), 2017https://www.cdc.gov/antibiotic-use/community/for-hcp/Penicillin-Allergy.htmlDate accessed: August 1, 2019 Google Scholar Yet more than 97% are not at risk for an acute allergic reaction to penicillin. 2 Fox S. Park M.A. Penicillin skin testing in the evaluation and management of penicillin allergy. Ann Allergy Asthma Immunol. 2011; 106: 1-7 Abstract Full Text Full Text PDF PubMed Scopus (58) Google Scholar Many agents recommended as first-line therapy for surgical infection prophylaxis are among the β-lactam pharmaceutical class, such as penicillin, aminopenicillins, cephalosporins, monobactams, and carbapenems (Table 1). 3 Bratzler D.W. Dellinger E.P. Olsen K.M. et al. Clinical practice guidelines for antimicrobial prophylaxis in surgery. Am J Health Syst Pharm. 2013; 70: 195-283 Crossref PubMed Scopus (1275) Google Scholar Studies indicate that 76% to 93% of patients who report a penicillin allergy receive second-line antibiotics for surgical infection prophylaxis. 4 Stone A.H. Kelmer G. MacDonald J.H. Clance M.R. King P.J. The impact of patient-reported penicillin allergy on risk for surgical site infection in total joint arthroplasty. J Am Acad Orthop Surg. 2019; ([Epub ahead of print])https://doi.org/10.5435/JAAOS-D-18-00709 Crossref Scopus (22) Google Scholar , 5 Blumenthal K.G. Ryan E.E. Li Y. Lee H. Kuhlen J.L. Shenoy E.S. The impact of a reported penicillin allergy on surgical site infection risk. Clin Infect Dis. 2018; 66: 329-336 Crossref PubMed Scopus (204) Google Scholar , 6 Beltran R.J. Kako H. Chovanec T. Ramesh A. Bissonnette B. Tobias J.D. Penicillin allergy and surgical prophylaxis: cephalosporin cross-reactivity risk in a pediatric tertiary care center. J Pediatr Surg. 2015; 50: 856-859 Abstract Full Text Full Text PDF PubMed Scopus (41) Google Scholar Table 1β-Lactam Antimicrobials in the Surgical Prophylaxis Guidelines 3 Bratzler D.W. Dellinger E.P. Olsen K.M. et al. Clinical practice guidelines for antimicrobial prophylaxis in surgery. Am J Health Syst Pharm. 2013; 70: 195-283 Crossref PubMed Scopus (1275) Google Scholar Penicillin Derivatives Cephalosporins Monobactam Carbapenem Ampicillin Cefazolin Aztreonam Ertapenem Ampicillin-sulbactam Cefotetan Piperacillin-tazobactam Cefoxitin Cefotaxime Ceftriaxone Cefepime Open table in a new tab Rachel C. Wolfe, PharmD, MHA, BCCCP, Pharmacy Department, Barnes-Jewish Hospital, St. Louis, MO

Most Penicillin-Allergic–Labeled Patients Don't Need Penicillin Skin Testing

About 10% of the U.S. population has received a penicillin allergy diagnosis, but most such patients are not truly allergic. As a method to “delabel”

Diagnosis of penicillin allergy: a MOFs-based composite hydrogel for detecting β-lactamase in serum.

An as-synthesized MOFs-based hydrogel exhibits high sensitivity for β-lactamase through an "ON-OFF-OFF-ON" luminescence trigger. It allows achieving an unprecedented strategy for the judgement of penicillin allergy via luminescence detection of β-lactamase in serum.

Patient and Prescriber Views of Penicillin Allergy Testing and Subsequent Antibiotic Use: A Rapid Review.

About 10% of U.K. patients believe that they are allergic to penicillin and have a “penicillin allergy label” in their primary care health record. However, around 90% of these patients may be mislabelled. Removing incorrect penicillin allergy labels can help to reduce unnecessary broad-spectrum antibiotic use. A rapid review was undertaken of papers exploring patient and/or clinician views and experiences of penicillin allergy testing (PAT) services and the influences on antibiotic prescribing behaviour in the context of penicillin allergy. We reviewed English-language publications published up to November 2017. Limited evidence on patients’ experiences of PAT highlighted advantages to testing as well as a number of concerns. Clinicians reported uncertainty about referral criteria for PAT. Following PAT and a negative result, a number of clinicians and patients remained reluctant to prescribe and consume penicillins. This appeared to reflect a lack of confidence in the test result and fear of subsequent reactions to penicillins. The findings suggest lack of awareness and knowledge of PAT services by both clinicians and patients. In order to ensure correct penicillin allergy diagnosis, clinicians and patients need to be supported to use PAT services and equipped with the skills to use penicillins appropriately following a negative allergy test result.

Prospective assessment of diagnostic tests for pediatric penicillin allergy: From clinical history to challenge tests

BackgroundDiagnostic guidelines for penicillin allergy in children recommend cumbersome protocols based partially on data from adults, which may be suboptimal for pediatric use. ObjectiveTo assess the accuracy of tools for diagnosis of penicillin allergy in children. MethodsA prospective, multicenter study was conducted in children with reported adverse events related to penicillin, excluding severe reactions. All patients underwent a uniform diagnostic protocol that consisted of clinical history, skin tests, serum specific IgE (sIgE), and, regardless of these results, drug provocation tests (DPTs). ResultsA total of 732 children (mean age, 5.5 years; 51.2% males) completed the allergy workup, including DPTs. Amoxicillin triggered 96.9% of all reactions. None of the patients with an immediate index reaction (IR) developed a reaction on DPT. Penicillin allergy was confirmed in 35 children (4.8%): 6 immediate reactions (17%) and 29 nonimmediate reactions (83%) on the DPT. No severe reactions were recorded. The allergist diagnosis based on the clinical history was not associated with the DPT final outcome. In 30 of 33 allergic patients (91%), the results of all skin tests and sIgE tests were negative. A logistic regression model identified the following to be associated with penicillin allergy: a family history of drug allergy (odds ratio [OR], 3.03; 95% confidence interval [CI], 1.33-6.89; P = .008), an IR lasting more than 3 days vs 24 hours or less (OR, 8.96; 95% CI, 2.01-39.86; P = .004), and an IR treated with corticosteroids (OR, 2.68; 95% CI, 1.30-5.54; P = .007). ConclusionConventional predictors of allergy to penicillin performed weakly. The authors propose straightforward penicillin provocation testing in controlled, experienced centers for the diagnosis of nonsevere penicillin allergy in children.

Hospitalizations in Children with a Penicillin Allergy Label: An Assessment of Healthcare Impact

Background: Beta-lactam allergy is overdiagnosed. Diagnosis of penicillin allergy has been associated with a greater use of hospital resources and an increased risk of antibiotic-resistant infections, although this issue remains poorly studied in children. We aimed to compare patient characteristics and use of hospital resources in hospitalized children with and without a record of penicillin allergy. Methods: We identified all hospitalizations in children labelled as being allergic to penicillin in a database containing all hospitalizations in Portuguese public hospitals between 2000 and 2014, and compared these with a similar number of age-, sex-, and main diagnosis-matched hospitalizations without a penicillin allergy label. Comparisons were made for length of hospital stay, comorbidities (Charlson Comorbidity Index), in-hospital mortality, and hospitalization costs. Results: We identified 1,718 hospitalizations corresponding to children labelled as penicillin-allergic. Compared with patients without such a label, these children had longer hospital stays (mean 5 vs. 4 days, p = 0.03) and a higher comorbidity index (mean 0.11 vs. 0.09, p < 0.001). Hospitalization costs were also higher (EUR 2,071 vs. 1,798), but the difference was not significant (p = 0.12). Conclusions: Hospitalizations of children labelled as allergic to penicillin are associated with longer hospital stays, more comorbidities, and a tendency towards higher hospitalization costs. An accurate diagnosis of penicillin allergy based on clinical history and confirmatory tests is therefore essential in all paediatric patients.

Clinical and economic burden of hospitalizations with registration of penicillin allergy

BackgroundPenicillin allergy is commonly reported, but only a minority of claimants has a confirmed diagnosis. Nevertheless, patients labeled as having penicillin allergy are treated with second-line antibiotics, which are more expensive and less effective, possibly increasing the risk of drug-resistant infections. ObjectiveTo compare hospitalizations with and without registration of penicillin allergy concerning their morbidity and hospital resource use. MethodsWe analyzed a national administrative database containing a registration of all Portuguese hospitalizations from 2000 to 2014. All episodes occurring in adults with a penicillin allergy registration were compared with an equal number of hospitalizations without such registration and matched for inpatients' age, sex, and main diagnosis. We compared those episodes concerning their length of stay, hospital price charges, comorbidities, and frequency of drug-resistant infections. Differences between medical and surgical hospitalizations were explored. ResultsHospitalizations with registration of penicillin allergy (n = 102,872) had a longer average length of stay than the remainder episodes (8 vs 7 days; P < .001) and higher hospital charges (3,809.0 vs 3,490.0 USD; P < .001). Inpatients with penicillin allergy registration also had a higher mean Charlson Comorbidity Index (0.91 vs 0.76; P < .001) and a significantly higher frequency of infections by several agents, including methicillin-resistant Staphylococcus aureus, Enterococcus species, and Escherichia coli. Among surgical episodes, septicemia was 1.2-fold more frequent among penicillin allergy cases. ConclusionHospitalizations with registration of penicillin allergy are associated with increased economic costs and frequency of infections by drug-resistant agents, reinforcing the need to establish a correct diagnosis of penicillin allergy.

The High Impact of Penicillin Allergy Registration in Hospitalized Patients

SM van Dijk, H Gardarsdottir, M Wassenburg. J Allergy Clin Immunol Pract. 2016;4(5):926–931 To assess the impact of a diagnosis of penicillin allergy in hospitalized patients. The study included all patients (children and adults) admitted at the University Medical Center in Utrecht, the Netherlands, over a 1-year period who underwent a standardized pharmacotherapeutic interview. There were 997 patients with documentation of penicillin allergy (Pen-A) and 2939 patients without documentation of penicillin allergy (non–Pen-A). This was a prospective, matched cohort study. Patients were registered as having penicillin allergy if the history demonstrated either an evaluation by …