Antibiotic Allergy Labels in Hospitalized Patients: Results of a Multicenter Cross-Sectional Study.

To determine the nature, prevalence and description accuracy of recorded antibiotic allergy labels (AALs) in a cohort of general medical inpatients, and to assess the feasibility of an oral antibiotic re-challenge study. Multicentre cross-sectional study. All patients admitted to the general medical units of Austin Health and Alfred Health, 18 May - 5 June 2015. Baseline demographics, medical and allergy history, infection diagnoses and antibiotic prescribing data for general medical inpatients were collected. A questionnaire was administered to clarify AAL history, followed by correlation of responses with electronic and admissions record descriptions. A hypothetical oral re-challenge in a supervised setting was offered to patients with low risk allergy phenotypes (non-immediate reaction, non-severe cutaneous adverse reaction, or unknown reaction more than 10 years ago). Of the 453 inpatients, 107 (24%) had an AAL (median age, 82 years; interquartile range, 74-87 years); 160 individual AALs were recorded, and there was a mismatch in AAL description between recording platforms in 25% of cases. Most patients with an AAL were women (64%; P <0.001), and more presented with concurrent immunosuppression than those without an AAL (23% v 8%; P <0.001). β-Lactam penicillins were employed less frequently in patients with an AAL (16% v 35%; P = 0.02), while ceftriaxone (32% v 20%; P = 0.02) and fluoroquinolones (6% v 2%; P = 0.04) were used more often. Fifty-four per cent of patients with AALs were willing to undergo oral re-challenge, of whom 48% had a low risk allergy phenotype. AAL prevalence in general medical inpatients was 24%, and was associated with excessive use of broad spectrum antibiotics. Allergies in a large proportion of patients with AALs were incorrectly documented, and were non-immune-mediated and potentially amenable to oral re-challenge. A direct oral re-challenge study in carefully selected patients with low risk allergy phenotypes appears feasible.

To examine whether antibiotic allergy labeling has a significant impact on clinical outcomes in children.The study included 1672 pediatric patients. The mean age of patients was 6.8 years (range: 0–18.7 years).Children with an antibiotic allergy label in their charts admitted to a tertiary care teaching hospital in Australia were retrospectively identified from April 2014 to April 2015 through chart review. Data collected included history of allergic reaction, antibiotic allergy label, diagnosis on admission, antibiotics prescribed, admitting specialty, length of stay, and hospital readmissions within 4 weeks and 6 months of discharge.Antibiotic allergies were recorded in 5.3% of the cohort, with β-lactams most commonly reported (85%). Increasing age was significantly associated with increased likelihood of having a documented allergy label, most commonly a β-lactam allergy label. Children with antibiotic allergy labels were more likely to receive macrolides, quinolones, lincosamides, and nitroimidazoles compared with patients without an allergy label. After adjusting for age, sex, diagnosis, and admitting specialty, an antibiotic allergy label was associated with prolonged length of hospital stay (odds ratio: 1.62; 95% confidence interval: 1.05–2.50).Researchers in this study found that antibiotic allergy labeling was associated with negative clinical outcomes in children, including longer hospital stays and greater use of broad-spectrum antibiotics when compared with patients without an antibiotic allergy label.This is the first study to examine the effect of antibiotic allergy labels on clinical outcomes in children. In addition to increased hospital stays, this study demonstrated increased use of reserve antibiotics. More liberal use of broad-spectrum antimicrobial agents is concerning because these medications can increase risk of multidrug resistance. Patients with mild to moderate reactions could potentially undergo allergy evaluation and be delabeled. Researchers in this study suggest that early delabeling may aid in mitigating adverse clinical outcomes in children with antibiotic allergy labels.

Antibiotic Allergy Labels in Children Are Associated with Adverse Clinical Outcomes

Association of antibiotic allergy labels with hospital length of stay

Antibiotic allergies are reported in 5-15% of children. This study aimed to evaluate the impact of common β-lactam antibiotic allergy labels (AALs) on hospital treatment, focusing on length of stay and appropriateness of antibiotic prescribing. This was a retrospective cohort study over 21 months at the Royal Children's Hospital Melbourne, Australia. A subset of children with the most common β-lactam allergies, and who required admission for intravenous antibiotics over a 12-month period, was analysed for appropriateness of prescribing. Non-allergic patients were matched to evaluate associations between AALs and hospital treatment. There were 98 912 children admitted over the study period, of whom 938 (1%) had at least one AAL on first admission. Of all encounters, 5145 (2.5%) were for children with AALs. The most common AALs were to amoxicillin and amoxicillin-clavulanic acid combinations (40.8%), cefalexin (14.4%) and trimethoprim-sulfamethoxazole (9.7%). For the subset, there were 66 admissions for children who required intravenous antibiotics. Documentation was adequate for 27% of AALs. Inappropriate prescribing occurred in almost half (47%). Hospital stay was longer for children with AALs (median 4.7days; IQR 2.3-9.2) compared to non-allergic controls (median 3.9days; IQR 1.9-6.8; P = .02). Children with AALs were more likely to receive restricted antibiotics (aOR 3.03; 95% CI, 1.45-6.30; P = .003). This is the first study to demonstrate high rates of inappropriate prescribing in children with AALs. Children with AALs were significantly more likely to receive restricted antibiotics and had a longer length of stay compared with non-allergic controls.

Characteristics, risk factors and clinical impact of penicillin and other antibiotic allergies in adults in the UK General Practice: A population-based cohort study.

Prevalence of Antibiotic Allergy Labels in a Tertiary Referral Center in Belgium

Antibiotic allergy labels are common and associated with adverse care. Most people with an antibiotic allergy label are found to be non-allergic on investigation. The aims of this study were to evaluate the burden and accuracy of antibiotic allergy labels at North Shore Hospital and to identify and assess beta-lactam specific allergies, and the potential impact of an inpatient antibiotic allergy service. An evaluation of documented inpatient adverse drug reaction (ADR) labels. Structured assessment of beta-lactam allergies was undertaken using the Austin Health tool. Three hundred and seven patients were reviewed; 78 patients had an antibiotic allergy label, with 102 individual labels. Fifty-five of these 78 patients underwent structured assessment. Forty-four patients had a beta-lactam-specific antibiotic allergy label. Using the Austin Health tool, 9/44 (20%) of beta-lactam-specific allergy labels could have been removed following a history alone and a further 16/44 (36%) would have been appropriate for direct oral challenge. Antibiotic allergy label accuracy was 64% for beta-lactam antibiotics, and 69% for non-beta-lactams. The prevalence of antibiotic specific allergies in our centre was similar to New Zealand and Australian statistics.1,2 Our study showed that a significant proportion of inpatients with a beta-lactam-specific allergy could be de-labelled on history or with a single dose challenge.

A growing body of evidence suggests that antibiotic allergy labels as documented in medical records are a risk factor for poor clinical outcomes. In this systematic review, we aimed to determine how antibiotic allergy labels influence 3 domains: antibiotic use and exposure, clinical outcomes, and healthcare-related costs. We performed a systematic review to identify studies reporting outcomes in patients with antibiotic allergy labels compared to nonallergic counterparts. The search included PubMed, EMBASE, Cochrane CENTRAL, EBSCO, Cochrane Database of Abstracts of Reviews of Effects and Web of Science. Two reviewers independently screened studies for inclusion and abstracted data. Studies were graded using the Newcastle-Ottawa quality assessment scale. Study outcomes included antibiotic use, clinical outcomes, and economic outcomes. In total, 41 studies met our criteria for inclusion. These studies varied in medical specialty, patient population, healthcare delivery system, and design, but most were conducted among adults age >18 years (85%) in the inpatient setting (82.5%). Among 34 studies examining antibiotic exposure, 32 (94%) found that patients with antibiotic allergy labels received more broad-spectrum antibiotics. Moreover, 31 studies examined clinical outcomes such as length of hospitalization, ICU admission, hospital readmission, multidrug-resistant or opportunistic infection, or mortality, and 27 (87%) found that allergy-labeled patients had at least 1 negative outcome. Of 9 studies examining healthcare costs, 7 (78%) found that allergy-labeled patients incurred significantly higher drug or hospital-related costs. Antibiotic allergy labels have negative effects on antibiotic use, clinical outcomes, and economic outcomes in a variety of clinical settings and populations.

Self-reported antibiotic allergies, also known as antibiotic allergy labels, are common and may lead to worse patient outcomes. Within immunocompromized patients, antibiotic allergy labels can lead to inappropriate use of antimicrobials and may limit options for prophylactic and therapeutic options in the posttransplant period. While antibiotic allergy delabeling is considered an important aspect of antibiotic stewardship protocols, evidence and awareness of its application in transplant recipients is limited. We describe our experience with an antibiotic allergy delabeling intervention in the pretransplant evaluation period and its impact on posttransplant antimicrobial utilization. This was a retrospective analysis of patients with an antibiotic allergy label who underwent evaluation for solid organ or stem cell transplantation between 2015 and 2020. Patients included in this analysis were those who completed pretransplant antibiotic allergy delabeling through our Drug Allergy Clinic and were retained in care for 6 months after transplant. Twenty-six of 27 patients underwent pretransplant antibiotic allergy delabeling and safely received the delabeled antibiotic posttransplant. There were no reported side effects to the delabeled antibiotic within 6 months posttransplant. Specific examination of sulfonamide (sulfa)-antibiotic delabeling showed cost savings of $254 to $2910 per patient in the posttransplant period compared to the use of alternative antibiotics for prophylaxis protocol. Antibiotic allergy delabeling prior to transplant is safe, is of high value, and should be considered in the pretransplant evaluation period.More resources are needed for the development of delabeling guidelines and support for broad implementation of pretransplant antibiotic allergy delabeling programs.

The safety and efficacy of direct oral challenge in trimethoprim-sulfamethoxazole antibiotic allergy

ObjectivesTime to initiation of effective antibiotic therapy is a strong predictor of survival for patients with sepsis presenting to the Emergency Department (ED). Antibiotic allergy labels (AALs) are a known barrier to timely sepsis management. The aim was to evaluate the influence of AALs on timely sepsis management for ED sepsis presentations in an Australian hospital.MethodsA retrospective cohort study was conducted for ED presentations requiring direct ICU admission for suspected sepsis, comparing patients with and without an AAL using propensity scores.ResultsBetween November 2018 and June 2021, 377 patients were included. The prevalence of an AAL was 29.6% (86/377). The median time to antibiotic administration was similar in the AAL versus non-AAL groups (51 versus 60 min, P = 0.11); there was no difference in mortality (14.1% versus 14.0%, P = 0.98) and length of stay (9.21 versus 10.10 days). The median time to antibiotic administration was shorter in those with Emergency Medicine (EM) pharmacist attendance versus those without (50 versus 92 min, P = 0.0001). Appropriateness of antibiotic prescription was 91.0% (343/377) for the overall cohort and was not associated with AALs, possibly due to our clear antimicrobial sepsis guidelines; however, EM pharmacist involvement was associated with increased antibiotic appropriateness (97.3% versus 88.4%, P = 0.00048).ConclusionsIn our Australian ED, AALs were not found to impact timeliness of antibiotic administration in patients with sepsis. EM pharmacist involvement was associated with improved timeliness and appropriateness of antibiotic selection in patients presenting with sepsis.

To determine the prevalence of antibiotic allergy labels (AALs) in Australian aged care residents and to describe the impact of labels on antibiotic prescribing practices. Point-prevalence survey. Australian residential aged care facilities. We surveyed 1,489 residents in 407 aged care facilities. Standardized data were collected on a single day between June 1 and August 31, 2018, for residents prescribed an antibiotic. An AAL was reported if it was documented in the resident's health record. Resident-level data were used to calculate overall prevalence, and antibiotic-level data were used to report relative frequency of AALs for individual antibiotics and classes. Among 1,489 residents, 356 (24%) had 1 or more documented AALs. The AALs for penicillin (28.3%), amoxicillin or amoxicillin/clavulanic acid (10.5%), cefalexin (7.2%), and trimethoprim (7.0%) were most commonly reported. The presence of an AAL was associated with significantly less prescribing of penicillins (OR, 0.43; 95% CI, 0.31-0.62; P < .001) and significantly more prescribing of lincosamides (OR, 4.81; P < .001), macrolides (OR, 2.03; P = .007), and tetracyclines (OR, 1.54; P = .033). Of residents with AALs, 7 residents (1.9%) were prescribed an antibiotic that was listed on the allergy section of their health record. A high prevalence of AALs was observed among residents of Australian aged care facilities, comparable to the prevalence of AALs in high-risk hospitalized patients. Significant increases in prescribing of lincosamide, macrolide, and tetracycline agents poses a potential risk to aged populations, and future studies must evaluate the benefits of AAL delabelling programs tailored for aged care settings.

Patients are sometimes mislabeled as having an immune-mediated antibiotic allergy in their medical records. Therefore, the aim of this study was to investigate the prevalence of subjects with non-immune mediated reactions to antibiotics using a standardized questionnaire. Subjects aged 18 years and older with a documented antibiotic allergy were identified and recruited from 2 outpatient clinics in the greater Chicago area. Subjects completed a standardized questionnaire during a single visit regarding their previous adverse reaction to an antibiotic. For subjects with multiple documented antibiotic allergies, 1 questionnaire was filled out for each antibiotic allergy. Investigators subsequently evaluated the questionnaire responses to determine whether the adverse reaction was a true immune-mediated allergic reaction or an adverse drug reaction. A total of 98 subjects were recruited with completion of 159 questionnaires. Eighteen subjects (18.37%, 95% CI: 10.7%, 26.3%) had antibiotic allergy labels with no corresponding immune-mediated reaction history. There were 35 allergy labels (22.0%, 95% CI: 14.7%, 29.4%) that were unlikely to be immune-mediated. Antibiotics with the highest percentage of clinical histories that were unlikely to be immune-mediated were macrolides (8 of 11 subjects), nitrofurantoin (1 of 2 subjects), and amoxicillin/clavulanate (2 of 8 subjects). The most common antibiotic allergy labels were penicillin (43 of 159 subjects), sulfonamides (25 of 159 subjects), and fluoroquinolones (21 of 159 subjects). Identification of adverse reactions to antibiotics that are unlikely to be immune-mediated can be accomplished using a standardized questionnaire in the outpatient setting. Improved identification of low-risk antibiotic allergy labels can guide de-labeling initiatives to improve antibiotic prescribing.

Characterizing Antibiotic Allergy Labels in a Large UK Hospital Population to Inform Antimicrobial Stewardship and Delabeling Assessment Strategy.