Oral challenge vs routine care to assess low-risk penicillin allergy in critically ill hospital patients (ORACLE): a pilot safety and feasibility randomised controlled trial

PURPOSE

Critically ill patients are vulnerable to penicillin allergy labels that may be incorrect. The validity of skin testing in intensive care units (ICUs) is uncertain. Many penicillin allergy labels are low risk, and validated tools exist to identify those amenable to direct oral challenge. This pilot randomised controlled trial explored the feasibility, safety, and validity of direct enteral challenge for low-risk penicillin allergy labels in critical illness.

METHODS

Consenting patients with a low-risk penicillin allergy label (PAL) (PEN-FAST risk assessment score < 3) in four ICUs (Melbourne, Australia) were randomised 1:1 to penicillin (250 mg amoxicillin or implicated penicillin) direct enteral challenge versus routine care (2-h post-randomisation observation for each arm). Repeat challenge was performed post -ICU in the intervention arm. Patients were reviewed at 24 h and 5 days after each challenge/observation.

RESULTS

We screened 533 patients. 130 (24.4%) were eligible and 80/130 (61.5%) enrolled (age median 64.5 years (interquartile range, IQR 53.5, 74), PEN-FAST median 1 (IQR 0,1)), with 40 (50%) randomised to direct enteral challenge. A positive challenge rate of 2.5% was identified. No antibiotic-associated serious adverse events were identified. 32/40 (80%) received a repeat challenge (zero positive). Post-randomisation, 13 (32%) of the intervention arm and 4 (10%) of the control arm received penicillin (odds ratio, OR 4.33 [1.27, 14.78] p = 0.019).

CONCLUSION

These findings support the safety, validity, and feasibility of direct enteral challenge for critically ill patients with PEN-FAST assessed low-risk penicillin allergy. The absence of false negative results was confirmed by subsequent negative repeat challenges. A relatively low recruitment to screened ratio suggests that more inclusive eligibility criteria and integration of allergy assessment into routine ICU processes are needed to optimise allergy delabelling in critical illness.

Association Between Early Patient Characteristics and IgE-Mediated Allergy in the Perioperative Setting

BACKGROUND

Early recognition of perioperative anaphylaxis, a life-threatening, usually IgE-mediated, immediate hypersensitivity, is essential, but bedside diagnosis is not always straightforward because clinical presentation may vary.

OBJECTIVES

To describe early characteristics of perioperative immediate hypersensitivity, with special attention to cutaneous phenotypes, and identify risk factors for IgE-mediated allergy.

METHODS

We retrospectively analyzed data from adults with suspected perioperative immediate hypersensitivity who were investigated in two academic medical centers. Multivariable logistic regression was conducted to evaluate associations among patient, clinical, and paraclinical characteristics and IgE-mediated allergy.

RESULTS

Of 145 enrolled patients, 99 (68.3%) and 46 (31.7%) were respectively categorized in the IgE-mediated allergy and non-allergy groups. Cutaneous vasoconstriction phenotype (pallor, piloerection, thelerethism, and sweating with or without cyanosis) occurring within minutes (or even 1 minute) of drug exposure was strongly associated with IgE-mediated allergy (adjusted odds ratio [aOR] = 28.02; 95% CI, 4.41-305.18). IgE-mediated allergy was always life-threatening in this setting. Other early factors associated with allergy were low end-tidal carbon dioxide 25 mm Hg or less (aOR = 5.45; 95% CI, 2.39-26.45), low mean arterial pressure 60 mm Hg or less (aOR = 3.82; 95% CI, 1.28-17.31), and early cutaneous vasodilation (erythema, urticaria, and/or angioedema) (aOR = 2.78; 95% CI, 0.73-20.54). Late cutaneous vasodilation after restoration of hemodynamics corroborated the diagnosis of allergy (aOR = 23.67; 95% CI, 4.94-205.09). The best-fit model including three readily available variables (cutaneous phenotype involving the three modalities [reference lack of cutaneous signs], low mean arterial pressure, and low end-tidal carbon dioxide) had an area under the curve of 0.91.

CONCLUSIONS

Cutaneous vasoconstriction phenotype is associated with the strongest risk of life-threatening allergy and thus may be regarded as pathognomonic of perioperative IgE-mediated anaphylaxis.

HLA-DRB1 is associated with cefaclor-induced immediate hypersensitivity

Background

Drug-induced hypersensitivity such as anaphylaxis is an important cause of drug-related morbidity and mortality. Cefaclor is a leading cause of drug induced type I hypersensitivity in Korea, but little is yet known about genetic biomarkers to predict this hypersensitivity reaction. We aimed to evaluate the possible involvement of genes in cefaclor induced type I hypersensitivity.

Methods

Whole exome sequencing (WES) and HLA genotyping were performed in 43 patients with cefaclor induced type I hypersensitivity. In addition, homology modeling was performed to identify the binding forms of cefaclor to HLA site.

Results

Anaphylaxis was the most common phenotype of cefaclor hypersensitivity (90.69%). WES results show that rs62242177 and rs62242178 located in LIMD1 region were genome-wide significant at the 5 × 10-8 significance level. Cefaclor induced type I hypersensitivity was significantly associated with HLA-DRB1∗04:03 (OR 4.61 [95% CI 1.51-14.09], P < 0.002) and HLA-DRB1∗14:54 (OR 3.86 [95% CI 1.09-13.67], P < 0.002).

Conclusion

LIMD1, HLA-DRB1∗04:03 and HLA-DRB1∗14:54 may affect susceptibility to cefaclor induced type I hypersensitivity. Further confirmative studies with a larger patient population should be performed to ascertain the role of HLA-DRB1 and LIMD1 in the development of cefaclor induced hypersensitivity.

Non-IgE-Mediated Immediate Drug-Induced Hypersensitivity Reactions

Immediate drug-induced hypersensitivity reactions (IDHSRs) have conventionally been attributed to an immunoglobulin E (IgE)-mediated mechanism. Nevertheless, it has now been acknowledged that IDHSRs can also occur independently of IgE involvement. Non-IgE-mediated IDHSRs encompass the activation of effector cells, both mast cell-dependent and -independent and the initiation of inflammatory pathways through immunogenic and nonimmunogenic mechanisms. The IDHSRs involve inflammatory mediators beyond histamine, including the platelet-activating factor, which activates multiple cell types, including smooth muscle, endothelium, and MC, and evidence supports its importance in IgE-mediated reactions in humans. Clinically, distinguishing IgE from non-IgE mechanisms is crucial for future treatment strategies, including drug(s) restriction, readministration approaches, and pretreatment considerations. However, this presents significant challenges because certain drugs can trigger both mechanisms, and their presentations can appear similarly, ranging from mild to life-threatening symptoms. Thus, history alone is often inadequate for differentiation, and skin tests lack a standardized approach. Moreover, drug-specific IgE immunoassays have favorable specificity but low sensitivity, and the usefulness of the basophil activation test remains debatable. Lastly, no biomarker reliably differentiates between both mechanisms. Whereas non-IgE-mediated mechanisms likely predominate in IDHSRs, reclassifying most drug-related IDHSRs as non-IgE-mediated, with suggested prevention through dose administration adjustments, is premature and risky. Therefore, continued research and validated diagnostic tests are crucial to improving our capacity to distinguish between these mechanisms, ultimately enhancing patient care.

Clinical characteristics and genetic HLA marker for patients with oxaliplatin-induced adverse drug reactions

BACKGROUND

Oxaliplatin is commonly used to treat gastrointestinal malignancies. However, its applications are limited due to potential adverse drug reactions (ADRs), particularly severe anaphylactic shock. There is no method to predict or prevent ADRs caused by oxaliplatin. Therefore, we aimed to investigate the genetic HLA predisposition and immune mechanism of oxaliplatin-induced ADRs.

METHODS

A retrospective review was performed for 154 patients with ADRs induced by oxaliplatin during 2016-2021 recorded in our ADR notification system. HLA genotyping was conducted for 47 patients with oxaliplatin-induced ADRs, 1100 general population controls, and 34 oxaliplatin-tolerant controls in 2019-2023. The in vitro basophil activation test (BAT) was performed and oxaliplatin-specific IgE levels were determined.

RESULTS

The incidence of oxaliplatin-induced ADRs and anaphylactic shock in our cohort was 7.1% and 0.15%, respectively. Of the 154 patients, 67.5% suffered rash/eruption; 26.0% of the patients who could not undergo oxaliplatin rechallenge were considered to show oxaliplatin-induced immune-mediated hypersensitivity reactions (HRs). The genetic study found that the HLA-DRB∗12:01 allele was associated with oxaliplatin-induced HRs compared to the general population controls (sensitivity = 42.9%; odds ratio [OR] = 3.4; 95% CI = 1.4-8.2; P = 0.008) and tolerant controls (OR = 12; 95% CI = 2.3-63.7; P = 0.001). The in vitro BAT showed higher activation of CD63+ basophils in patients with oxaliplatin-induced HRs compared to the tolerant controls (P < 0.05). Only four patients (8.5%) with oxaliplatin-induced ADRs were positive for oxaliplatin-specific IgE.

CONCLUSIONS

This study found that 26.0% of patients with oxaliplatin-induced ADRs could not undergo oxaliplatin rechallenge. HLA-DRB∗12:01 is regarded as a genetic marker for oxaliplatin-induced hypersensitivity.

Drug hypersensitivity reactions: review of the state of the science for prediction and diagnosis

Drug hypersensitivity reactions (DHRs) are a type of adverse drug reaction that can occur with different classes of drugs and affect multiple organ systems and patient populations. DHRs can be classified as allergic or non-allergic based on the cellular mechanisms involved. Whereas non-allergic reactions rely mainly on the innate immune system, allergic reactions involve the generation of an adaptive immune response. Consequently, drug allergies are DHRs for which an immunological mechanism, with antibody and/or T cell, is demonstrated. Despite decades of research, methods to predict the potential for a new chemical entity to cause DHRs or to correctly attribute DHRs to a specific mechanism and a specific molecule are not well-established. This review will focus on allergic reactions induced by systemically administered low molecular weight (LMW) drugs with an emphasis on drug- and patient-specific factors that could influence the development of DHRs. Strategies for predicting and diagnosing DHRs, including potential tools based on the current state of the science, will also be discussed.

A US-Based Multicenter Retrospective Report of Perioperative Anaphylaxis, 2010-2021

BACKGROUND

US-based perioperative anaphylaxis (POA) studies are limited to single-center experiences. A recent report found that a serum acute tryptase (sAT) >9.8 ng/mL or mast cell activation (MCA) can predict POA causal agent identification. Urinary mast cell mediator metabolites (uMC) have not been studied in POA.

OBJECTIVE

To analyze the epidemiologic data of POA, to determine if sAT or MCA can predict suspected causal agent identification, and to evaluate uMC utility in POA.

METHODS

This study is a retrospective multicenter review of POA cases that were subcategorized by suspected causal agent identification status. sAT, MCA (defined as sAT >2 + 1.2 × serum baseline tryptase), and uMC (N-methylhistamine [N-MH], 11β-prostaglandin-F2α [11β-PGF2α], leukotriene E4 [LTE4]) were recorded.

RESULTS

Of 100 patients (mean age 52 [standard deviation 17] years, 94% adult, 50% female, 90% White, and 2% Hispanic) with POA, 73% had an sAT available, 41% had MCA, 16% had uMC available, and 50% had an identifiable suspected cause. POA cases with an identifiable suspected cause had a positive MCA status (100% vs 78%; P = .01) compared with POA with an unidentifiable cause. An elevated median sAT did not predict causal agent identification. Positive uMC were not associated with suspected causal agent identification during POA. Patients with positive uMC had a higher median sAT (30 vs 6.45 ng/mL; P = .001) and MCA status (96% vs 12%; P = .001) compared with negative uMC patients. Patients with POA had an elevated acute/baseline uMC ratios: 11β-PGF2α ratio > 1.6, N-MH ratio >1.7, and LTE4 ratio >1.8.

CONCLUSIONS

The presence of MCA in POA is associated with suspected causal agent identification. Positive uMC possibly correlate with a higher sAT level and MCA status but require further study. The authors suggest applying an acute/baseline uMC ratio (11β-PGF2α ratio >1.6, N-MH ratio >1.7, and LTE4 ratio >1.87) in patients with POA for MCA when a tryptase level is inconclusive during POA evaluations.

Dapagliflozin-induced drug Reaction with Eosinophilia and Systemic Symptoms (DRESS) Followed By Acute Interstitial Nephritis (AIN): A Case Report

A 78-year-old male was admitted to the hospital with acute renal failure and generalized erythema after starting dapagliflozin 10 mg/day for chronic kidney disease (CKD). A skin biopsy revealed superficial perivascular dermatitis with eosinophils. A renal biopsy revealed lymphocytic and eosinophilic infiltration of the interstitium, and focal tubulitis. The patient was diagnosed with a dapagliflozin-induced drug reaction with eosinophilia and systemic symptoms (DRESS), followed by acute interstitial nephritis (AIN), and prednisolone therapy was therefore initiated. The patient's renal function improved, and erythema disappeared. To our knowledge, this is the first report of DRESS caused by dapagliflozin, and the patient was successfully treated with prednisolone.

Effectiveness of Carboplatin-Prescreening Intradermal Skin Tests to Reduce Unanticipated Immediate Hypersensitivity Reactions: A Comparative Study

BACKGROUND

Carboplatin administration poses a risk of immediate hypersensitivity reactions (IHRs) that tend to increase with repeated administration and are mostly IgE-mediated.

OBJECTIVE

This study evaluated the usefulness of carboplatin-prescreening intradermal skin tests (IDTs).

METHODS

Carboplatin-prescreening IDTs were routinely conducted in patients with a history of receiving six or more carboplatin cycles beginning in January 2021. The primary objective was to assess disparities in the incidence of unanticipated IHRs to carboplatin administration. We compared patients in the intervention group (from 2021 to 2022) and those who did not undergo prescreening IDTs under the same conditions (preintervention group, from 2019 to 2020). Secondary objectives included evaluating the sensitivity and specificity of the prescreening IDT and the incidence of carboplatin IHR according to the number of infusion cycles.

RESULTS

The intervention group was composed of 67 patients who were administered 347 carboplatin cycles whereas the preintervention group included 96 patients who were administered 464 carboplatin cycles. The risk of unanticipated carboplatin IHRs decreased by 83.2% in the intervention group compared with results in the preintervention group (preintervention group, 3.45%, n = 16 vs intervention group, 0.58%, n = 2; P = .005). The prescreening IDT showed a sensitivity and specificity of 77.78% and 99.41%, respectively. The risk of newly developed IHRs based on the number of carboplatin cycles was less than 1% (cycles 1-5), 2.11% (cycle 6), 3.90% (cycles 7-12), 2.90% (cycles 13-18), and 0.74% (cycles 19 and greater), respectively.

CONCLUSIONS

Initiating carboplatin-prescreening IDTs from the seventh cycle on significantly reduced the risk of unanticipated IHRs.

Drug-Induced Anaphylaxis Uncommon in Mastocytosis: Findings From Two Large Cohorts

BACKGROUND

Anaphylaxis is a common feature of patients with mastocytosis, particularly with Hymenoptera venoms. Hence, it is hypothesized that patients with mastocytosis may have an increased susceptibility to developing drug-induced anaphylaxis (DIA). Patients and medical practitioners are therefore concerned when there is a need to use various drugs. However, this issue has not been systematically investigated.

OBJECTIVE

To investigate the prevalence and clinical characteristics of anaphylaxis to various types of drugs among patients with mastocytosis.

METHODS

A retrospective study was conducted among 470 consecutive patients (18 years and older) with confirmed clonal mast cell diseases recruited from 2 independent mastocytosis reference centers. All patients underwent a comprehensive, individualized allergy workup with evaluation of the (self)reported drug hypersensitivity.

RESULTS

The overall prevalence of DIA was 6.3%, accounting for one-third of the confirmed drug hypersensitivity reactions. Nonsteroidal anti-inflammatory drugs were the most common elicitors of DIA (56%), followed by perioperative agents (23%) and antibiotics (13%). Anaphylactic reactions were severe in most cases, with 43% of patients experiencing hypotensive syncope. All drug-related hypersensitivity reactions occurred before mastocytosis was diagnosed.

CONCLUSIONS

The prevalence of DIA in mastocytosis tends to be higher than in the general population, but is overall low. However, its severity is more pronounced. Our results suggest that patients with mastocytosis with a previous reaction to drugs should undergo a thorough allergy workup. Well-tolerated drugs can be further used without specific precautions.

Frequencies of HLA-B alleles in Indonesian Malay Ethnic

Background

The HLA-B alleles have been used as a marker to predict drug-induced adverse reactions and as a major contributor to hypersensitivity reactions. We examined the feasibility of HLA-B alleles as pharmacogenomic markers of drug-induced hypersensitivity in an Indonesian Malay Ethnic.

Methods

Fifty-eight Indonesian individuals of Malay ethnicity were enrolled in this study. HLA-B alleles were determined using reverse sequence-specific oligonucleotide probe coupled with xMAP technology.

Results

HLA-B*15:02 (15.52%), HLA-B*35:05 (9.48%), and HLA-B*07:05 (7.76%) were frequent alleles in the Indonesian Malay ethnic populations. We discovered at least eight pharmacogenomics markers of drug-induced hypersensitivity: HLA-B*15:02, HLA-B*15:21, HLA-B*13:01, HLA-B*35:05, HLA-B*38:02, HLA-B*51:01, HLA-B*57:01, and HLA-B*58:01. HLA-B*15:02 was in the same serotype group with HLA-B*15:21, which is a B-75 serotype associated with genetic predisposition for carbamazepine-induced Stevens-Johnson syndrome and toxic epidermal necrolysis. The Indonesian population, represented by Malay, Javanese, and Sundanese ethnicities, was similar to South East Asian, Han Chinese, and Taiwanese populations based on HLA-B*15:02 frequency as the most common allele found in Malay ethnics.

Conclusion

We provided valuable information on the frequency of drug hypersensitivity-associated HLA-B alleles in Indonesian Malay ethnic population, which can improve treatment safety.

How to manage drug-virus interplay underlying skin eruptions in children

The majority of viral rashes occurring during an antibiotic therapy are considered as a drug hypersensitivity reaction (DHR). Differentiating a viral rash versus a DHR is difficult or even impossible. In delayed DHRs the interplay between viruses and drugs is summarized according to the recent literature. The question is if the same reaction will again occur in case of drug re-exposure in absence of the concomitant viral infection because of persistent immune reactivity. Epstein Barr Virus (EBV) and Human Herpes virus 6 (HHV-6) models are analyzed in case of maculopapular exanthemas (MPEs) and drug reaction with eosinophilia and systemic symptoms (DRESS) over a course of drug therapy. MPEs are the most common skin manifestation during a viral infection and a concomitant drug therapy. In type IVb reactions to drugs a hapten/pro-hapten mechanism and a pharmacological interaction (p-i mechanism) are described as the 2 major ways to make T cells response functional. Rarely the altered repertoire model is involved. The Human Leukocyte Antigen (HLA) predisposition is an additional essential factor that can facilitate DHR. In MPEs rarely a DHR is confirmed by allergy testing. Severity and duration of MPEs, the presence of eosinophilia and systemic symptoms make more reliable the persistent nature of the reaction. Research on this topic is needed in order to provide the clinicians with instruments to decide when to suspect future reactions upon drug re-exposure even in the absence of a viral infection, because those patients should be investigated by a complete drug allergy work up.

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

BACKGROUND

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 in vitro 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.

OBJECTIVE

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.

RESULTS

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.

CONCLUSIONS

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.

Enhancing Patient-Reported Outcome Measures for Drug Hypersensitivity: A Validated 6-Item Quality-of-Life Questionnaire for Patients With Drug Hypersensitivity

BACKGROUND

Drug hypersensitivity reactions (DHRs) can significantly impair patients' health-related quality of life (HRQoL). However, tools for HRQoL assessment for patients with DHR are time-consuming and remain underutilized.

OBJECTIVE

To develop and validate an optimized version of the Drug Hypersensitivity Quality-of-Life Questionnaire (DrHy-Q) designed for everyday clinical use.

METHODS

Item response theory (IRT), a statistical framework for psychometric measurement, was used to evaluate the 15 questions from the original DrHy-Q for their respective item difficulty, discrimination, and information using prospective data from 243 patients with histories of suspected/confirmed DHR before allergy workup. Accordingly, the best-performing items were identified to develop a 6-item optimized version (DrHy-Q6), which was subsequently validated with another prospective cohort of 156 patients.

RESULTS

All 15 items of the original DrHy-Q demonstrated satisfactory parameters in IRT analysis, including very high discrimination (>1.7), appropriate difficulty (in between -1.5 and 1.5), and good information (a high and broad peak in the information curve). Six items with top-ranked IRT parameters were identified to construct an optimized version, which we named the DrHy-Q6. The DrHy-Q6 demonstrated a 1-factor structure with an improved fit compared with the original DrHy-Q (comparative fit index = 0.985, Tucker-Lewis index = 0.974), excellent convergent validity (unadjusted Pearson correlation with the full version = 0.955; adjusted = 0.894, P < .001), reliability (Cronbach's α and McDonald's ω = 0.93), divergent validity (Pearson correlation with all Short Form 12-item Health Survey Version 2 subscales <0.60, P < .001), and discriminant validity (significantly higher scores with multiple DHR labels [42.45 ± 27.26 vs 32.93 ± 26.66], P = .013).

CONCLUSIONS

From an IRT perspective, the DrHy-Q and all its constituent items are psychometrically valid for HRQoL assessment. We propose an optimized 6-item version (DrHy-Q6) as an abbreviated alternative for assessing HRQoL in patients with DHR, especially for routine use in clinical practice. Patients and physicians may benefit from its streamlined length and simpler scoring algorithm.

Record of strep throat infections in Italy: what is needed to know about penicillin allergy? The point of view from the Italian Society of Pediatric Allergy and Immunology (SIAIP)

Notifications of invasive group A streptococcal (iGAS) infections have significantly increased in many European Countries compared to the previous season. In Italy, there has been an increase in streptococcal pharyngitis and scarlet fever cases since January 2023, which sparked concerns about a GAS epidemic in the pediatric population. This rise may be ascribed to the GAS infection season that began earlier than usual (off-season outbreak) and the increase in the spread of respiratory viruses and viral coinfections that raised the risk of iGAS disease. Moreover, this phenomenon was also facilitated by increased travel after reduced GAS circulation during the COVID-19 pandemic.The increase in cases of GAS disease has raised some critical issues regarding the potential reactions to administering amoxicillin, the first-line antibiotic therapy, many of which have been erroneously labeled as "allergy."For these reasons, the Italian Society of Pediatric Allergy and Immunology (SIAIP) intends to provide simple clinical indications to help pediatricians manage GAS pharyngitis, discerning the allergic from non-allergic drug hypersensitivity.

[Risk factors associated to adverse drug events in hospitalized patients]

OBJECTIVE

To determine prevalence, causes and risk factors of ADE in hospitalized patients.

METHODS

Analytical, observational, case-control study of patients with ADE. For statistical analysis, the following were calculated: percentages, frequencies, averages; odds ratio, χ2 test and multiple binary logistic regression. Data analysis was carried out with the Statistical Package, for the Social Sciences 23 program.

RESULTS

A 132 patients were registered: 66 cases (26 EM and 40 RAM) and 66 controls; with average age of 35 years (SD 17.41). The prevalence of adverse drug events was 3.6%. The most frequently reported medications: antibiotics and anti-inflammatories. The frequency of adverse events by gender was: 39.3% men and 60.7% women. The services with the greatest patient care: emergencies, surgery; the most frequent route of administration: intravenous (32.3%). The main symptoms: skin. (32.3%) frequent symptoms: cutaneous. Associated symptoms RAM: type A pruritus (OR: 8.5; p = 0.001; IC95%: 0.035-0.393), type B pruritus (OR: 11; p = 0.001; CI95%: 0.021-0.368) urticaria (OR: 19; p = 0.005; IC95%: 0.007-0.412). Risk factors Associated EAM: female (OR: 2.6; p = 0.05; CI95%: 1.33-5.43), history of allergy (OR: 3.4; p = 0.033; CI95%: 1.04-8.40), prolonged hospital stays (OR: 5.4; p = 0.023; IC95%: 3.82-6.74).

CONCLUSIONS

Patient safety is a priority when prescribing any drug, which represents a key point in prevention.

One-Bag 8-Step Ferric Carboxymaltose Desensitization Protocol for Patients with a History of Hypersensitivity Reactions to Iron Preparations

INTRODUCTION

Iron deficiency is the most common cause of anemia in both sexes, although it is more common in women. Intravenous (IV) iron replacement is preferred in patients who cannot tolerate oral treatment or when iron stores need to be replenished rapidly. In this study, we wanted to share the ferric carboxymaltose (FCM) desensitization protocol that we self-created and successfully applied.

METHODS

This retrospective cross-sectional study included patients with a history of hypersensitivity reactions (HSRs) to IV or oral iron replacement and patients who were planned to receive IV iron replacement but were referred to the allergy clinic because of have risk factors (atopic diseases, history of HSR to other drugs, high serum tryptase levels, etc.) for HSRs. Before desensitization, some of the patients underwent skin tests (skin prick test and intradermal test) with FCM, and the results were recorded. Skin tests were not performed in patients with a history of drug use (antihistamine, systemic steroid, omalizumab, etc.) that affected the results of skin tests. All patients underwent a one-bag 8-step desensitization protocol with 500 mg FCM and were observed for 2 h after desensitization.

RESULTS

A total of 15 patients (14 females and 1 male) with a mean age of 41.13 ± 11.18 years were included in the study. When the patients were evaluated in terms of the risk of allergic reactions according to their clinical history, 8 patients had a history of anaphylaxis with iron preparations (FCM, n = 4; ferric hydroxide sucrose, n = 2; iron [II] glycine sulfate, n = 1; and iron [III] hydroxide polymaltose, n = 1), and 7 patients had a history of HSR other than anaphylaxis with iron preparations (urticaria, n = 6 [FCM, n = 2; iron (II) glycine sulfate, n = 2; and iron (III) hydroxide polymaltose, n = 2] and urticaria + angioedema [ferric hydroxide sucrose, n = 1]). Desensitization was successfully completed in all patients. No HSR was observed during or after the procedure in any of the patients.

CONCLUSION

IV iron replacement is a very effective method, especially in cases where iron stores need to be replenished more rapidly. In patients with a history of iron HSR or at risk of developing HSR, replacement can be safely performed without an allergic reaction with successful desensitization protocols.

Hypersensitivity reactions with first-line antituberculosis drugs and outcomes of rapid desensitizations

Background

Data about drug hypersensitivity reactions with first-line antituberculosis drugs and their management is limited. Rapid drug desensitization seems to be an appropriate management.

Objective

Evaluate the efficacy of the rapid desensitization protocols in patients who had a reaction phenotypically compatible with immediate-type drug hypersensitivity with first-line antituberculosis drugs and identify possible risk factors of breakthrough reactions during the protocols.

Methods

This is a retrospective study of active tuberculosis patients who had a reaction phenotypically compatible with immediate-type drug hypersensitivity with first-line antituberculosis drugs and underwent desensitization with the drugs used during the reaction. Characteristics of drug hypersensitivity and breakthrough reactions, and outcomes of rapid desensitizations were recorded.

Results

One hundred and seventy-nine patients were included in the study. Most of the initial reactions (n = 132, 73.7%) occurred within the first week of treatment and were mild (n = 146, 81.6%). A total of 690 desensitizations were performed. Desensitizations were successfully completed without any breakthrough reaction in 103 (57.5%) patients and in 29 of 36 (80.6%) patients after a breakthrough reaction. The overall success of desensitizations were found to be 95% (132 of 139 patients). Most of the breakthrough reactions (84%) were mild. Sixteen patients had breakthrough reactions with multiple drugs. Although pyrazinamide was the most common culprit of breakthrough reactions and had the lowest desensitization success, it had the highest rate of a single breakthrough reaction (p < 0.001). Timing of the initial reaction and concomitant breakthrough reaction with ethambutol were found to have increased the risk for breakthrough reaction caused by rifampicin (p = 0.017 and p = 0.010 respectively).

Conclusion

The rapid desensitization protocols used in this study provide a successful and effective management of the patients with a reaction phenotypically compatible with immediate-type drug hypersensitivity with first-line antituberculosis drugs.

Risk factors for allergy documentation in electronic health record: A retrospective study in a tertiary health center in Switzerland

BACKGROUND

Most hospitals use electronic health records (EHR) to warn health care professionals of drug hypersensitivity (DH) and other allergies. Indiscriminate recording of patient self-reported allergies may bloat the alert system, leading to unjustified avoidances and increases in health costs. The aim of our study was to analyze hypersensitivities documented in EHR of patients at Lausanne University Hospital (CHUV).

METHODS

We conducted a retrospective study on patients admitted at least 24 h to CHUV between 2011 and 2021. After ethical clearance, we obtained anonymized data. Because culprit allergen could be either manually recorded or selected through a list, data was harmonized using a reference allergy database before undergoing statistical analysis.

RESULTS

Of 192,444 patients, 16% had at least one allergy referenced. DH constituted 60% of all allergy alerts, mainly beta-lactam antibiotics (BLA) (30%), NSAID (11%) and iodinated contrast media (ICM) (7%). Median age at first hospitalization and hospitalization length were higher in the allergy group. Female to male ratio was 2:1 in the allergic group. Reactions were limited to the skin in half of patients, and consistent with anaphylaxis in 6%. In those deemed allergic to BLA, culprit drug was specified in 19%, 'allergy to penicillin' otherwise. It was impossible to distinguish DH based on history alone or resulting from specialized work-up.

CONCLUSIONS

Older age, longer hospital stays, and female sex increase the odds of in-patient allergy documentation. Regarding DH, BLA were referenced in 4% of inpatient records. Specific delabeling programs should be implemented to increase data reliability and patient safety.

Different Patterns of Response in Hypersensitivity Reactions to Arylpropionic Acid Derivatives

BACKGROUND

Ibuprofen and other arylpropionic acid derivatives (APs) are among the most consumed nonsteroidal anti-inflammatory drugs worldwide at all age ranges; however, little is known about drug hypersensitivity reactions (DHRs) they induce.

OBJECTIVE

To characterize in detail patients reporting DHRs to APs.

METHODS

We prospectively evaluated patients with symptoms suggestive of AP-DHRs and analyzed their clinical characteristics, reported reactions, and diagnostic approaches.

RESULTS

Six hundred sixty-two patients confirmed as hypersensitive to APs were included: 489 with cross-reactive reactions (CRs) (73.86%) and 173 with selective reactions (SRs) (26.13%). The percentage of subjects reporting reactions to ibuprofen and dexketoprofen was higher in CRs (P = .005 and P = .01, respectively), whereas naproxen and ketoprofen were more frequently involved in SRs (P = .0002 and P = .00001, respectively). The most frequent symptoms induced by ibuprofen, dexketoprofen, and naproxen were isolated angioedema and urticaria, combined or not with angioedema in both CRs and SRs. The result of nasal provocation test with lysine acetylsalicylate was positive in 156 cases (77.14% in patients showing exclusively respiratory symptoms, and in 68.18% of those with both cutaneous and respiratory involvement). To confirm diagnosis, drug provocation test with acetylsalicylic acid was required in 246 CR patients (50.3%), whereas in 28 SR patients (16.18%) drug provocation test with the culprit AP was required.

CONCLUSIONS

Skin is the organ most commonly involved in AP-DHRs, with ibuprofen and dexketoprofen inducing most frequently CRs, and naproxen and ketoprofen SRs. More studies are necessary to clarify the underlying mechanism in DHRs induced by APs.

Drug Reaction with Eosinophilia and Systemic Symptom Syndrome Due to Everolimus: A Case Report

Drug reaction with eosinophilia and systemic symptom (DRESS) is a life-threatening drug hypersensitivity reaction that is characterized by skin rash, hematological abnormalities (eosinophilia, atypical lymphocytosis), lymphadenopathy, and internal organ involvement (liver, kidneys, and lung). Many drugs may cause DRESS syndrome, the most frequently reported of which are antiepileptics and allopurinol. In this case report, a patient who developed DRESS syndrome due to everolimus was presented herein.

A new pathway for penicillin delabeling in Norway

Background

Penicillin allergy is self-reported by 3-10% of patients admitted to hospital. The label is wrong in 90% of the cases and has severe health implications. Penicillin-delabeling can reverse the negative effects of the label, and pathways adapted to local practice are needed. No tools are available in Norway for penicillin delabeling outside an allergy clinic.

Objective

To create and validate the first penicillin delabeling pathway applicable outside an allergy clinic in Norway.

Methods

An interdisciplinary taskforce created a penicillin allergy delabeling program (PAD) adapted to the Norwegian health care system. This was validated in a prospective, single-center study. Very low-risk and low-risk patients underwent a direct oral penicillin challenge and high-risk patients were referred for allergologic evaluation.

Results

One-hundred forty-nine patients declaring penicillin allergy were included. Seventy-four (50%) were very-low- and low risk patients suitable for a direct oral penicillin challenge resulting in only 1 mild reaction. Sixty high-risk patients were eligible for an oral penicillin challenge after allergologic evaluation; 3 patients reacted non-severely.

Conclusion

We have created and demonstrated feasibility of the first penicillin delabeling program (PAD) applicable in a hospital setting outside an allergy clinic in Norway. Our data suggest this is safe and beneficial, with 49% patients delabeled through a direct oral penicillin challenge, performed without any serious adverse events, and an overall 87% delabeling rate.

Qualitative analysis of healthcare provider perspectives to evaluating beta-lactam allergies

BACKGROUND

There is a lack of understanding of the barriers reported by healthcare providers when evaluating beta-lactam allergies, but knowledge of these barriers is required for practical and effective implementation interventions.

METHODS

Twenty-five healthcare providers, consisting of physicians, nurses and pharmacists practicing in the areas of intensive care, emergency medicine, infectious disease and general hospital practice, were interviewed between September 2021 and July 2023. Twenty-three of these providers were practising in the USA. A semi-structured interview guide grounded in the Theoretical Domain Framework was used for the interviews. Deductive and inductive analysis was performed on the interview transcripts, and translated into intervention recommendations using the Behaviour Change Wheel.

RESULTS

Widely held beliefs included a lack of clear policy for the evaluation of allergies, confusing or missing documentation of allergy information, confidence in their own and their colleagues' ability to evaluate allergies when information is available, and pharmacists as the provider most equipped to evaluate beta-lactam allergies.

CONCLUSIONS

Health systems should adopt and disseminate policies for the evaluation of beta-lactam allergies, and promote the use of pharmacists in the evaluation of drug allergies when possible. Allergy sections of electronic health records should be reworked to encourage unambiguous documentation of allergy reactions and support using previously tolerated beta-lactam antibiotics.

Analysis of drug-induced anaphylaxis cases using the Japanese Adverse Drug Event Report (JADER) database - secondary publication

BACKGROUND

The epidemiology of drug-induced anaphylaxis using the Japanese nationwide database has been not reported, even though drugs are a common trigger of anaphylaxis. The aim of this study was to describe the epidemiological profile of cases of drug-induced anaphylaxis, including fatal cases, using the data from the Japanese Adverse Drug Event Report database (JADER).

METHODS

We extracted data regarding drug-related adverse events, between April 2004 and February 2018, published in JADER by the Pharmaceuticals and Medical Devices Agency. We analyzed cases of anaphylaxis occurring between January 2005 and December 2017. The drug classification was based on the Japanese Standard Commodity Classification.

RESULTS

There were 16,916 cases of anaphylaxis reported during the study period. Among them, 418 fatalities were registered. The incidence of drug-induced anaphylaxis and fatal cases was 1.03 cases/year per 100,000 population and 0.03 cases/year, respectively. The most frequent causes of anaphylaxis were diagnostic agents, including X-ray contrast media (20.3%), and biological preparations, such as human blood preparations (20.1%). In fatal cases, diagnostic agents (28.7%) and antibiotic preparations (23.9%) were the most commonly associated types of drugs.

CONCLUSIONS

The frequency of drug-induced anaphylaxis and fatalities in Japan remained unchanged over the 13-year period analyzed in this study. Diagnostic agents and biological preparations were the most frequent causes of anaphylaxis; however, fatalities were most frequently caused by either diagnostic agents or antibiotic preparations.

Impact of histamine-2 antagonist shortage on the incidence of hypersensitivity reactions to paclitaxel: a reconsideration of premedication protocols in France (PACLIREACT Study)

PURPOSE

An international shortage of ranitidine led to adjustments in premedication regimens for paclitaxel-based chemotherapy in early October 2019. In this study, we implemented and evaluated an anti-allergic protocol without histamine-2 antagonists (H2As) and aimed to assess the risk of hypersensitivity reactions (HSRs) to the different premedication regimens used.

METHODS

We conducted a single-center observational retrospective study of paclitaxel administrations (7173 administrations in 831 patients). Between January 2019 and December 2020, all allergies reported were recorded. A mixed logistic regression model was implemented to predict the risk of allergy at each injection and to account for repeated administration per patient.

RESULTS

A total of 27 HSRs occurred in 24 patients. No protective effect was observed for H2A when comparing paclitaxel injections with H2A premedication versus without H2A (OR = 1.12, p = 0.84). There was also no significant difference in risk of HSR for famotidine versus ranitidine (OR = 0.79, p = 0.78). However, the risk of HSRs was significantly lower for paclitaxel injections with corticosteroids than for those without (OR = 0.08, p = 0.03). In addition, the risk of HSR was significantly higher for the first, second, or third paclitaxel injections than for the subsequent injections (OR = 10.1, p < 0.001).

CONCLUSION

We did not find substantial evidence of an increased risk of HSR due to the absence of H2A in the premedication protocols for paclitaxel. Thus, in contrary to the existing literature on paclitaxel, our findings support the use of a premedication protocol without H2A.

Drug Hypersensitivity Reactions

Drug hypersensitivity reactions are a diverse group of reactions mediated by the immune system after exposure to a drug. The Gell and Coombs classification divides immunologic DHRs into 4 major pathophysiologic categories based on immunologic mechanism. Anaphylaxis is a Type I hypersensitivity reaction that requires immediate recognition and treatment. Severe cutaneous adverse reactions (SCARs) are a group of dermatologic diseases that result from a Type IV hypersensitivity process and include drug reaction with eosinophilia and systemic symptom (DRESS) syndrome, Stevens-Johnson Syndrome (SJS), toxic epidermal necrolysis (TEN), and acute generalized exanthematous pustulosis (AGEP). Other types of reactions are slow to develop and do not always require rapid treatment. Emergency physicians should have a good understanding of these various types of drug hypersensitivity reactions and how to approach the patient regarding evaluation and treatment.

Drug-induced Stevens Johnson syndrome and toxic epidermal necrolysis: Interpreting the systematic reviews on immunomodulatory therapies

Drug-induced Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are non-immunoglobulin E-mediated severe cutaneous adverse reactions with a high risk of morbidity, mortality, and physical and mental health impact. These are associated with certain high-risk drugs, human leukocyte antigen (HLA)-specific genotypes and ethnicities. HLA class I-restricted oligoclonal CD8 cytotoxic T-cell responses occur at the tissue level in SJS/TEN. Cytotoxic T cells are the T effector cells that result in keratinocyte apoptosis (cell death) mediated by T effector molecules granzyme B, perforin, granulysin, gamma interferon, tumor necrosis factor-alpha, and lipocalin-2. The clinical hallmarks of SJS/TEN include fever, ≥2 mucosal involvements (ocular, oral, and genital), and positive Nikolsky sign with epidermal detachment. Systematic reviews on immunomodulatory treatments remain limited by the paucity of randomized controlled trials, heterogeneity of studies, and non-standardization of outcome measures. Preventive HLA genotype screening before the prescription of carbamazepine and allopurinol may further reduce the incidence of SJS/TEN. The role of immunomodulatory treatments in SJS/TEN is at present not supported by robust evidence from systematic reviews given the lack of randomized controlled trials. The evidence for improved survival with off-label use of corticosteroids plus intravenous immunoglobulins, ciclosporin plus intravenous immunoglobulins, and ciclosporin alone has not been demonstrated by network meta-analyses and meta-regression. In the real-world clinical setting, systemic corticosteroids (in SJS and overlap SJS/TEN), ciclosporin, and etanercept (in TEN) appear to be the off-label treatments currently most widely used.

Drug Reaction With Eosinophilia and Systemic Symptoms: A Systematic Review

BACKGROUND

Drug reaction with eosinophilia and systemic symptoms (DRESS) is a potentially life-threatening drug reaction; recognizing the diversity of its clinical presentations, implicated drugs, and management modalities can aid in diagnosis and reduce morbidity and mortality.

OBJECTIVE

To review the clinical features, drug causes, and treatments deployed in DRESS.

METHODS

This review was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines to review publications relating to DRESS published between 1979 and 2021. Only publications with a RegiSCAR score of 4 or greater were included (indicating "probable" or "definite" DRESS). The PRISMA guidelines were used for data extraction and the Newcastle-Ottawa scale for quality assessment (Pierson DJ. Respir Care 2009;54:1372-8). The main outcomes included implicated drugs, patient demographics, clinical manifestations, treatment, and sequelae for each included publication.

RESULTS

A total of 1124 publications were reviewed, and 131 met the inclusion criteria, amounting to 151 cases of DRESS. The most implicated drug classes were antibiotics, anticonvulsants, and anti-inflammatories, although up to 55 drugs were implicated. Cutaneous manifestations were present in 99% of cases, with a median onset of 24 days and maculopapular rash the most common morphology. Common systemic features were fever, eosinophilia, lymphadenopathy, and liver involvement. Facial edema was present in 67 cases (44%). Systemic corticosteroids were the mainstay of DRESS-specific treatment. A total of 13 cases (9%) resulted in mortality.

CONCLUSION

DRESS diagnosis should be considered in the presence of a cutaneous eruption, fever, eosinophilia, liver involvement, and lymphadenopathy. The class of implicated drug may influence outcome, as allopurinol was associated with 23% of cases that resulted in death (3 cases). Given potential DRESS complications and mortality, it is important that DRESS is recognized early so that any suspect drugs are ceased promptly.

DNA methylation of ITGB2 contributes to allopurinol hypersensitivity

BACKGROUNDS

HLA-B*58:01 allele was strongly associated with allopurinol induced severe cutaneous adverse drug reaction (SCAR). However, HLA-B genotype is not sufficient to predict the occurrence of allopurinol-induced SCAR.

OBJECTIVE

To discover DNA methylation markers for allopurinol-induced SCAR which may improve the prediction accuracy of genetic testing.

STUDY DESIGN

The study was designed as a retrospective case-control clinical study in multicenter hospitals across Taiwan, Mainland China, Malaysia and Canada. 125 cases of allopurinol-induced SCAR patients and 139 cases of allopurinol tolerant controls were enrolled in this study during 2005 to 2021.

RESULTS

The results of genome-wide DNA methylation assay of 62 patients revealed that ITGB2 showed strong discriminative ability of allopurinol-induced SCAR in both HLA-B*58:01 positive and negative patients with AUC value of 0.9364 (95% CI 0.8682-1.000). In validation study, significant hypermethylation of ITGB2 were further validated in allopurinol-induced SCAR patients compared to tolerant controls, especially in those without HLA-B*58:01(AUC value of 0.8814 (95% CI 0.7121-1.000)). Additionally, the methylation levels of 2 sites on ITGB2 were associated with SCAR phenotypes. Combination of HLA-B*58:01 genotyping and ITGB2 methylation status could improve the prediction accuracy of allopurinol-induced SCAR with the AUC value up to 0.9387 (95% CI 0.9089-0.9684), while the AUC value of HLA-B*58:01 genotyping alone was 0.8557 (95% CI 0.8030-0.9083).

CONCLUSIONS

Our study uncovers differentially methylated genes between allopurinol-induced SCAR patients and tolerant controls with positive or negative HLA-B*58:01 allele and provides the novel epigenetic marker that improves the prediction accuracy of genetic testing for prevention of allopurinol-induced SCAR.

Risk Factors of Challenge-Proven Beta-Lactam Allergy in Children with Immediate and Non-Immediate Mild Cutaneous Reactions

INTRODUCTION

Beta-lactam (BL) antibiotics are the most often involved drugs in allergic reactions. Mild cutaneous reactions such as maculopapular exanthema or urticaria are the most common presenting complaints of BL allergy in the pediatric population. However, it can be challenging to distinguish BL-induced allergy from reactions due to infections or other reasons. In this study, we aimed to determine the clinical characteristics and potential risk factors of true BL allergy in children with suspected mild cutaneous reactions to BLs.

METHODS

We evaluated children who were admitted to our pediatric allergy clinic with suspected BL allergy in between January 2015 and March 2020. Patients with a history suggestive of immediate and non-immediate mild cutaneous reactions were included in the study. The oral challenge test (OCT) with the culprit drug was performed on all patients to confirm the diagnosis.

RESULTS

Two hundred fourteen (119 male and 95 female) patients with a median age of 4.9 years were evaluated. BL allergy was confirmed in 10.7% (23) of the patients, according to the OCT results. Most of the proven allergic reactions were of the immediate type (73.9%), and urticaria was the most common presenting complaint (60.8%) in proven BL-allergic patients. The negative predictive value of penicillin-G skin testing was 89.7% for immediate-type penicillin allergy and 93.4% for non-immediate reactions. Also, positive predictive value of penicillin-G skin testing was 50% for immediate and 25% for non-immediate reactions. In the multivariate logistic regression analysis, a history of proven drug allergy (Exp (B): 7.76, 95% CI: 1.88-31.97, p = 0.005) was found to be the risk for BL allergy.

CONCLUSION

This study highlighted that OCTs should be performed to confirm the diagnosis in patients suspected of immediate and non-immediate mild cutaneous reactions to BLs and remove the overestimated "BL allergy" label. In these patients, a history of proven drug allergy might be a risk factor for true BL allergy.

Clavulanic Acid Is a Leading Culprit Beta-Lactam in Immediate Allergic Reactions to Penicillins

PURPOSE

Clavulanate, a beta-lactam associated with amoxicillin, is frequently prescribed in patients at all ages. Recent data implicate amoxicillin-clavulanate in up to 80% of beta-lactam allergy cases. We assessed clavulanate's role in inducing allergic reactions to this combination treatment, with a focus on selective immediate reactions.

METHODS

Adults (≥ 16 years) reporting a history of immediate reactions to amoxicillin-clavulanate were evaluated through a beta-lactam allergological workup, using modified European Academy of Allergy and Clinical Immunology guidelines. Patients first underwent skin testing, and if negative, drug provocation tests. Expected outcomes were: Group A, subjects with immediate reaction to classical penicillin group determinants (penicilloyl polylysine, minor determinants mixture, and/or penicillin G); Group B, subjects with selective immediate reaction to amoxicillin; Group C, subjects with selective immediate reaction to clavulanate and Group D, those immediate reactions with co-sensitization to clavulanate plus penicillin group determinants or amoxicillin.

RESULTS

Of 1,170 included patients, 104 had immediate reactions: 36.5% to penicillin group determinants (Group A), 26.9% to amoxicillin (Group B), 32.7% to clavulanate (Group C), and 3.8% to clavulanate plus penicillin determinants or amoxicillin (Group D). Diagnosis was made by skin testing in 79%, 75% and 47% of the patients, respectively, in the first 3 groups (P < 0.001). Drug provocation tests were necessary to establish most other diagnoses. Anaphylaxis predominated over urticaria/angioedema in all groups.

CONCLUSIONS

Selective immediate reactions to clavulanate accounted for over a third of cases with confirmed reactions after amoxicillin-clavulanate intake, with more than half experiencing anaphylaxis. Within this group, skin test sensitivity was below 50%. People taking amoxicillin-clavulanate may also be co-sensitized to both drugs.

DRESS syndrome: A literature review and treatment algorithm

Drug reaction with eosinophilia and systemic symptoms, known by its acronym in English as DRESS (Drug Reaction with Eosinophilia and Systemic Symptoms), clinically manifests with fever, facial edema, lymphadenopathy, a morbilliform rash, and organ involvement. Laboratory results reveal leukocytosis, atypical lymphocytes, eosinophilia, and alterations of liver and kidney function tests. The actual incidence of DRESS is unknown, because it may vary depending on the type of medication and the immune status of each patient; also, because many cases remain undiagnosed or untreated. The drugs most associated with DRESS include antiepileptics, antibiotics, antituberculosis, and non-steroidal anti-inflammatory agents (NSAIDs). Its diagnosis is sometimes made late and can become a challenge. The diagnostic criteria proposed by the international Registry of Severe Cutaneous Adverse Reactions (RegiSCAR) help to establish the diagnosis through a score system based on clinical and laboratory findings. The first step to identify the culprit is a thorough clinical history that includes all suspects, emphasizing those most known to cause DRESS syndrome according to the context and the literature. A skin biopsy may also be helpful in the diagnostic process. Patch testing is the test of choice to search for the culprit in cases of DRESS. Regarding prognosis, the estimated mortality due to DRESS is 3.8%. The main causes of mortality include fulminant hepatitis and liver necrosis. Several indicators of poor prognosis have been identified and these include an eosinophil count above 6000 × 10³/μL, thrombocytopenia, pancytopenia, leukocytosis and coagulopathy. This article aims to review the evidence available regarding the epidemiology, pathophysiology, clinical and laboratory findings, diagnosis, and treatment of DRESS.

Lenalidomide Desensitization for Delayed Cutaneous Reaction: A Case Series and Review of the Literature

BACKGROUND

Lenalidomide is commonly used for treatment of multiple myeloma (MM) as well as other hematological disorders. Cutaneous adverse reactions occur frequently and withholding lenalidomide treatment may have implications for prognosis.

OBJECTIVE

To evaluate the role of lenalidomide desensitization in patients with cutaneous adverse reactions.

METHODS

A retrospective review of patients referred for lenalidomide desensitization between May 2019 and May 2022 at a tertiary hospital. All patients underwent a 6-week outpatient desensitization with premedication.

RESULTS

There were 12 patients: 10 males and 2 females with a median age of 65 years. All had MM with autologous stem cell transplantation and lenalidomide 10 mg daily added for maintenance therapy. Most patients (n = 8) had a generalized maculopapular exanthem with or without pruritus. All patients had delayed cutaneous reactions; the median time to onset was 14 days (range 2-28 d). Six patients tolerated desensitization: 5 on the first attempt and 1 after 3 attempts and supplementary oral prednisolone. Four patients underwent multiple (≤3) attempts at desensitization owing to breakthrough symptoms. In patients who failed desensitization, recurrence of symptoms occurred variably, either early (within days), within weeks, or delayed by more than 1 month.

CONCLUSIONS

Lenalidomide desensitization is worthwhile and allows continuation of treatment. In our MM cohort, lenalidomide desensitization was successful in only 50% of cases, including some cases in whom ongoing symptoms were mitigated by cotreatment with antihistamine.

The Safety of the Direct Drug Provocation Test in Beta-Lactam Hypersensitivity in Children: A Systematic Review and Meta-Analysis

BACKGROUND

Direct drug provocation test (DPT) without prior skin testing (ST) has been investigated in children suspected of being at risk for beta-lactam (BL) hypersensitivity reaction (HSR). However, no systematic review and meta-analysis has investigated the efficacy and safety of direct DPT for BL-HSR in children.

OBJECTIVE

To investigate the prevalence of BL-HSR by direct DPT and the safety of direct DPT in children.

METHODS

We searched MEDLINE, EMBASE, Web of Science, and CINAHL from their inception to July 23, 2022, for studies that performed direct DPT in children with suspected BL-HSR, or for studies that performed DPT in all cases with ST results, but they ignored the ST results. The true prevalence was defined as the proportion of children who experienced an HSR during direct DPT. Safety was determined according to the proportion of children who developed a dangerous reaction following DPT.

RESULTS

Twenty-eight studies with 8,334 direct challenges were included. Fifteen studies included patients who presented with either immediate or nonimmediate HSR, and the majority of the index reactions were nonsevere. Amoxicillin/amoxicillin-clavulanic acid was the most commonly used during the DPT. The pooled prevalence of confirmed BL-HSR was 5.23% (95% CI 4.17-6.39; I² = 72%). Immediate and nonimmediate HSR were reported in 0.8% (95% CI 0.43-1.25; I² = 55.1%) and 3.69% (95% CI 2.66-4.87; I² = 79.77%), respectively. Severe reactions were found in 3 cases with the frequency of 0.036% (95% CI 0.012-0.112; I² = 0%).

CONCLUSIONS

The prevalence of BL-HSR by direct DPT was 5.23%, and the frequency of severe reactions from direct DPT was very low (0.036%). Our findings support direct DPT as a safe and effective delabeling tool in children with suspected nonsevere BL-HSR.

Dynamic reaction picklist for improving allergy reaction documentation: A usability study

OBJECTIVE

To assess novel dynamic reaction picklists for improving allergy reaction documentation compared to a static reaction picklist.

MATERIALS AND METHODS

We developed three web-based user interfaces (UIs) mimicking the Mass General Brigham's EHR allergy module: the first and second UIs (i.e., UI-1D, UI-2D) implemented two dynamic reaction picklists with different ranking algorithms and the third UI (UI-3S) implemented a static reaction picklist like the one used in the current EHR. We recruited 18 clinicians to perform allergy entry for 10 test cases each via UI-1D and UI-3S, and another 18 clinicians via UI-2D and UI-3S. Primary measures were the number of free-text entries and time to complete the allergy entry. Clinicians were also interviewed using 30 questions before and after the data entry.

RESULTS AND DISCUSSIONS

Among 36 clinicians, less than half were satisfied with the current EHR reaction picklists, due to their incomprehensiveness, inefficiency, and lack of intuitiveness. The clinicians used significantly fewer free-text entries when using UI-1D or UI-2D compared to UI-3S (p < 0.05). The clinicians used on average 51 s (15 %) less time via UI-1D and 50 s (16 %) less time via UI-2D in completing the allergy entries versus UI-3S, and there was not a statistically significant difference in documentation time for either group between the dynamic and static UIs. Overall, 15-17 (83-94 %) clinicians rated UI-1D and 13-15 (72-83 %) clinicians rated UI-2D as efficient, easy to use, and useful, while less than half rated the same for UI-3S. Most clinicians reported that the dynamic reaction picklists always or often suggested appropriate reactions (n = 30, 83 %) and would decrease the free-text entries (n = 26, 72 %); nearly all preferred the dynamic picklist over the static picklist (n = 32, 89 %).

CONCLUSION

We found that dynamic reaction picklists significantly reduced the number of free-text entries and could reduce the time for allergy documentation by 15%. Clinicians preferred the dynamic reaction picklist over the static picklist.

COVID-19 vaccine allergy advice and guidance: The experience of a UK tertiary referral centre

Objective

The objective was to review COVID-19 vaccine allergy advice and guidance requests received and assess the impact of advice outcome on vaccination outcome.

Design

A retrospective analysis of requests for advice and guidance regarding COVID-19 vaccine allergy was completed using an electronic referral system from February 2021 to January 2022.

Participants

A total of 1265 independent patient requests for advice were received from primary care. Full vaccination information was available on 1210 patients who were included in the analysis.

Main outcome measures

We evaluated the specific outcome of request for advice (written advice versus allergy consultation), rate of vaccination, vaccination combinations, and tolerance of vaccination.

Results

Of the 1210 patients included, 959 (79%) were female. Eight hundred and ninety-six (74%) requests were managed with written advice only and of these 675 (75%) patients went on to be vaccinated. Overall, 891 (74%) of the population were vaccinated with 2 or more doses.Two hundred and nineteen patient consultations were undertaken with 109 (50%) prior to the first vaccination. Forty-nine (45%) consultations prior to vaccination were undertaken due to a label of anaphylaxis to vaccination in the past. Vaccination was recommended for all patients, and 78 (72%) of these received a first dose. Eight of these patients (10%) had symptoms within 1 h of vaccine administration.One hundred and ten (50%) consultations were undertaken for adverse reactions post COVID-19 vaccination, with 84 (76%) concerning immediate symptoms. Thirty patients (27%) who had a consultation had had adrenaline administered post vaccination. One patient had biopsy confirmed Stevens Johnson Syndrome and was referred to Dermatology. All others due for further doses (107 patients) were recommended to have subsequent doses with 49 (45%) offered the same vaccine. Eighty-nine patients had a vaccine administered post adverse reaction and 79 (88%) tolerated the dose.Skin testing and challenge to polyethylene glycol were negative in the 8 patients tested.

Conclusions

Over 1000 requests for advice and guidance were received during the review period, managed mainly with written advice. The overwhelming majority of requests for advice and consultations were for females, with equal distribution both pre- and post-COVID-19 vaccine administration. Vaccination was recommended in all but 1 patient (with biopsy confirmed Stevens Johnson Syndrome). Polyethylene glycol allergy was not confirmed in any patient, nor did any patient have confirmed anaphylaxis when the vaccine was administered under our supervision, suggesting that type 1 mediated hypersensitivity is uncommon even in this "high risk" population.

Current situation of anaphylaxis in Japan: Data from the anaphylaxis registry of training and teaching facilities certified by the Japanese Society of Allergy - secondary publication

BACKGROUND

Anaphylaxis is a potentially fatal severe systemic hypersensitivity reaction that causes symptoms in multiple organs such as the skin, respiratory tract, and gastrointestinal tract; however, no nationwide epidemiological survey on anaphylaxis has been conducted in Japan. This survey aimed to elucidate the triggers and treatment of anaphylaxis in Japan.

METHODS

Between February 2015 and October 2017, we prospectively collected clinical data on the triggers and treatment of patients who developed anaphylaxis or were admitted to the emergency room with anaphylaxis in the training and teaching facilities of the Japanese Society of Allergology.

RESULTS

This study included 79 of the 451 affiliated facilities (18%), and a total of 767 patients were enrolled; 73% of them were aged <18 years and 7% had in-hospital triggers. The most common triggers were food (68%), drugs (12%), food-dependent exercise-induced anaphylaxis (5%), insects (4%), and oral immunotherapy (3%), with drugs being the most common in-hospital trigger and food being the most common out-of-hospital trigger. Intramuscular injection of adrenaline was administered therapeutically to 38% of the patients, with 10% requiring multiple doses. Adrenaline auto-injectors were used in 12% of out-of-hospital patients.

CONCLUSIONS

The present survey revealed the most common triggers and treatments for anaphylaxis in Japan. Self-management and adrenaline administration as first-line treatment may not be done sufficiently. Therefore, it is necessary to thoroughly educate and train patients and physicians about anaphylaxis.

Delayed-Type Heparin Allergy: Intravenous Tolerance Despite Inflammatory Skin Reaction After Subcutaneous Injection

BACKGROUND

Heparin allergy most frequently manifests as delayed-type hypersensitivity (DTH) causing an itchy inflammatory skin reaction at the site of subcutaneous injection. An important differential diagnosis is circumscribed skin necrosis due to heparin-induced thrombocytopenia.

OBJECTIVES

An inflammatory skin reaction to subcutaneously injected heparin generally entails the quest for alternative anticoagulation; concerns may particularly arise in an emergency situation requiring intravenous heparin administration.

METHODS

All heparin DTH cases seen in our department over the last 17 years underwent standardized allergy diagnostics including challenge testing, that is, subcutaneous injection of fondaparinux and intravenous administration of unfractionated heparin (UFH).

RESULTS

Of a total of 50 patients with confirmed heparin allergy, DTH was found in 48 (96.0%), and immediate-type, presumably IgE-mediated hypersensitivity was diagnosed in only 2 (4.0%). In the 48 DTH cases, intradermal testing revealed broad cross-reactivity between UFH and low-molecular-weight heparins (LMWH) including nadroparin, dalteparin, and enoxaparin. Cross-reactivity with (or concomitant sensitization to) fondaparinux was seen in only 3 (6.3%) cases. Intravenous administration of UFH was tolerated by all 45 patients challenged, despite DTH to UFH and LMWH as demonstrated by intradermal testing.

CONCLUSIONS

If an inflammatory skin reaction at the site of subcutaneously injected heparin is observed or reported without any evidence of skin necrosis or thrombocytopenia, intravenous administration of UFH seems to be sufficiently safe and may be considered without allergy testing if urgently indicated in an emergency situation. Fondaparinux is the most suitable alternative for subcutaneous application.

Tuberculosis treatment-related lichenoid drug eruptions

Tuberculosis is one of the leading causes of death from infectious diseases in adults worldwide. Drug hypersensitivity in tuberculosis is an important problem affecting the treatment process. Although treatment is started with isoniazid, rifampicin, ethambutol, and pyrazinamide in drug-sensitive tuberculosis patients, it may not always be continued in this way. When hypersensitivity develops under antituberculosis treatment, type 4 hypersensitivity is the most common, and maculopapular drug eruption develops as a subgroup. Lichenoid drug eruption is very rare. We present our case who was diagnosed with pulmonary tuberculosis, who developed lichenoid drug eruption while receiving treatment, and whose treatment was completed by giving the new regimen with successful desensitization.

Treatment with IL5-/IL-5 receptor antagonists in drug reaction with eosinophilia and systemic symptoms (DRESS)

Purpose

Drug reaction with eosinophilia and systemic symptoms (DRESS) is a severe delayed drug hypersensitivity reaction with exanthema, eosinophilia, and organ manifestations. After culprit drug withdrawal, systemic corticosteroids (CS) are the most widely used treatment, often requiring high doses for months. Blocking the IL-5/IL‑5 receptor axis with mepolizumab, reslizumab, and benralizumab is a promising targeted treatment with a good safety profile and no immunosuppressive effect. The aim of this study is to summarize current experience with the anti-IL5/IL-5-receptor therapy in DRESS.

Methods

A retrospective analysis of all patients diagnosed with DRESS and treated with mepolizumab, reslizumab, or benralizumab in DRESS was performed. In addition, a PubMed-Medline search for publications on DRESS with anti-IL-5/IL‑5 receptor treatment was performed.

Results

Of the 14 cases identified, 6 patients were treated with mepolizumab, 6 with benralizumab, 1 patient with reslizumab, and 1 patient was switched from benralizumab to mepolizumab. The main indication for an IL‑5 blockade was a therapy-refractory course (7/14 [50.0%]), recurrent relapses (3/14 [21.4%]), and severe organ dysfunction (2/14 [14.3%]). In 13/14 (93%) cases, a rapid clinical improvement with suppression of eosinophilia and reduction of CS could be achieved. In all but two cases under mepolizumab (dose 100-600 mg) or reslizumab (dose according to body weight), two or more doses were necessary until resolution of DRESS. In 4/7 cases under benralizumab, a single 30 mg dose was sufficient.

Conclusion

Blockade of the IL-5/IL‑5 receptor axis appears to be a promising treatment in DRESS with fast clinical improvement, which may allow more rapid reduction of CS, and a good safety profile. In addition, a summary of recommendations on when to use blockade of the IL-5/IL‑5 receptor axis in DRESS treatment is provided.

Anaphylaxis in older adult patients: a 10-year retrospective experience

Background

Despite the worldwide increase in life expectancy and the elderly population, very little is known about the characteristics of anaphylaxis in older adults.

Methods

A retrospective scan was made of the files of patients who presented at the Allergy Unit of our clinic between October 2011 and October 2021. The study included 971 patients aged ≥18 years who met the criteria for diagnosis of anaphylaxis. The patients were separated into 2 groups of adults (18–64 years) and older adults (≥65 years).

Results

The adult group included 887 (91.3%) patients and the older adult group, 84 (8.7%) patients. Comorbid diseases were seen more frequently in the older adults than in the adult group (p < 0.001). Drugs were seen to be the most common trigger of anaphylaxis in both groups, and this was more common in the older adult group (p = 0.039). Food was a more common trigger of anaphylaxis in the adult group than in the older adult group (p = 0.017). In both groups, the skin was the organ most affected, and was less affected in the older adults than in the adults (p = 0.020). Cardiovascular symptoms were seen significantly more and respiratory symptoms significantly less in the older adult group (p < 0.001, p = 0.002, respectively). Admission to the hospital and the intensive care unit was more frequent in the older adult group and rates of adrenalin administration were higher compared to the adult group (p < 0.001 for all).

Conclusion

Anaphylaxis in the older adults is generally caused by drugs. Older adults were found to have more cardiovascular symptoms and more frequent adrenalin injections, hospitalizations and intensive care unit admissions.

Practical Implementation of Genetics: New Concepts in Immunogenomics to Predict, Prevent, and Diagnose Drug Hypersensitivity

Delayed drug hypersensitivities are CD8⁺ T cell-mediated reactions associated with up to 50% mortality. Human leukocyte antigen (HLA) alleles are known to predispose disease and are specific to drug, reaction, and patient ethnicity. Pretreatment screening is recommended for a handful of the strongest associations to identify and prevent drug use in high-risk patients. However, an incomplete predictive value implicates other HLA-imposed risk factors, and low carriage of many identified HLA-risk alleles combined with the high cost of sequence-based typing has limited economic viability for similar recommendation of screening across drugs and health care systems. For mitigation, an expanding armory of low-cost polymerase chain reaction-based screens is being developed, and HLA-imposed risk factors are being discovered. These include (1) polymorphic variants of metabolic and endoplasmic reticulum aminopeptidase enzymes toward multiallelic screening with increased predictivity; (2) regulation by immune checkpoint inhibitors, enabling detolerized animal models of human disease; and (3) immunodominant T cell receptors (TCR) on clonally expanded CD8⁺ T cells. For the latter, HLA risk-restricted TCR provides immunogenomic strategies and samples from a single patient to identify novel HLA-risk associations in underserved minority populations, tissue-relevant effector biomarkers toward earlier diagnosis and treatment, and HLA-TCR-presented immunogenic structures to aid future drug development.

Screening the European pharmacovigilance database for reports of clozapine-related DRESS syndrome: 47 novel cases

Clozapine-related drug reaction with eosinophilia and systemic symptoms (DRESS) syndrome is a rare adverse reaction. We aimed to screen a large pharmacovigilance database to identify clozapine-related DRESS cases, even if otherwise reported and provide a clinical overview. We screened spontaneous reports of clozapine-related DRESS syndrome in EudraVigilance database applying the European Registry on Severe Cutaneous Adverse Drug Reactions (RegiSCAR) criteria and scores to identify probable/definite DRESS syndrome cases. Clinical and demographic characteristics of included cases were provided and associations between RegiSCAR scores, and time to develop/recover DRESS were assessed. In a total of 262,146 adverse drug reactions reports for 75,190 clozapine-treated patients, 596 cases fulfilled RegiSCAR criteria; ultimately, 51 cases were rated as probable/definite DRESS according to RegiSCAR scores, of which 4 were previously published as case reports. The mean age of patients was 41.06 years (43.1% females), with 13 patients (25.5%) receiving reported co-medication with other DRESS culprit drugs. Median time between clozapine initiation and DRESS symptoms was 25 days. Clozapine dose was associated with days to develop symptoms (Spearman's ρ 0.40, p = 0.03). Organ involvement was reported in all cases followed by fever (n = 49; 96.1%) and eosinophilia (n = 47; 92.2%). Treatment involved clozapine discontinuation for 37 patients (72.5%), while 3.9% (n = 2) of cases ended fatally. Clozapine rechallenge was undertaken in 25 patients (49.0%). The screening of the EudraVigilance database revealed 47 novel clozapine-related DRESS cases, and only one was originally reported as DRESS. Clozapine-related DRESS may occur with clozapine monotherapy not only during dose titration, but also during maintenance treatment.

Usability of Three Graphical User Interfaces for Drug Allergy Documentation

The current drug allergy documentation module in the electronic health record of our institution is in a free-text format. Two versions of a structured and coded drug allergy documentation module were developed. Twenty-five physicians tested the three interfaces via 3x5 test scenarios. The usability was measured for each interface with a system usability scale questionnaire. Both new versions scored significantly better than the current free-text version. User feedback will be used to further optimize the new module.

How to Take a Good Clinical History in Cases of Allergic Reactions to Medications

The clinical history is the cornerstone of the doctor´s work. When assessing patients consulting for a suspected hypersensitivity reaction to a drug, the details collected in the patient´s clinical history are essential when deciding which tests to perform and for making recommendations about which drugs the patient should avoid and which can be taken. This area is especially important today, since many patients are labeled as allergic to drugs, especially penicillins, without this being the case. This article reviews the importance of the clinical history in a patient with a hypersensitivity reaction to a drug and considers which data should be collected. Likewise, a record-based model is proposed to help standardize the clinical history.