Preventing Overrides of Severe Drug Allergy Alerts Initiative: an Implemented System Upgrade.

Administering medications to patients with documented drug hypersensitivity reactions (DHR) poses a significant risk for adverse events, ranging from mild reactions to life-threatening incidents. Electronic healthcare systems have revolutionized the modern clinical decision-making process, with built in warnings. However, as these alerts become a routine part of healthcare provider's workflow, alert fatigue becomes a challenge. This study was conducted within the Ministry of National Guard Health Affairs (MNGHA), a government healthcare system in Saudi Arabia. A taskforce of experts was formed to develop an electronic path that would prevent unintentional overrides of severe drug allergy alerts. The system underwent rigorous testing, and monitoring parameters were established. We outline the implementation of a system upgrade designed to trigger an alternative interruption in the computerized physician order entry (CPOE) process, distinct from the regular allergy pop-up alerts. The alternate path is activated upon a CPOE with a drug-to-drug match and a documented severe drug allergy symptom, necessitating co-signature form another prescriber before proceeding. The adopted upgrade is a proactive approach to enhance medication safety in electronic healthcare systems, ensuring that serious allergy-related warnings are not overridden, ultimately enhancing patient safety. Further monitoring will confirm the safety and effectiveness of this measure. This study provides a model for institutions seeking to prevent allergy-related harm within their patient population.

Delayed drug hypersensitivity to anti-tuberculosis drug: a new desensitization scheme.

Introduction: Tuberculosis is a communicable illness and one of the leading causes of death, especially in developing countries like Turkey. One of the problems that must be managed well in the treatment of tuberculosis is drug hypersensitivity. The first-line agents are very important for the success of treatment. Alternative drugs are more toxic and less successful in treatment. Therefore, it is very important to be able to include first-line drugs in the post-hypersensitivity regimen. At this point, the success of desensitization comes to the fore. There are fewer studies on rapid drug desensitization in delayed-type drug hypersensitivity to anti-tuberculosis drugs. Aim: The primary aim of the study was to determine the prevalence of delayed-type hypersensitivity reactions in drug-sensitive cases; the secondary aim was to determine the appropriate treatment management. Material and methods: This was a retrospective study. Demographic features, tuberculosis diagnostic indicator, clinical signs of developing a hypersensitivity reaction, reaction time, desensitization scheme and treatment were evaluated. Results: A total of 41 tuberculosis cases were included in the study. Twenty-six of the cases were male; mean age (mean ± SD) 55.44 ±16.93 years; 70.7% of them were diagnosed bacteriologically; 70.7% of them were diagnosed with pulmonary tuberculosis. The most common skin finding was maculopapular drug eruption. The development time (mean ± SD) of the reaction in patients who developed a reaction was 34.93 ±39.62 days. The responsible agent could be identified in 15 reactions. The most common drug responsible for the reaction was rifampicin. Successful desensitization was achieved in 19 (46.3%) cases with the sensitive regimen. The duration of treatment was 8.97 ±3.44 months. When evaluated in terms of treatment results, cure and treatment completion were accepted as treatment success. In this case, 30 (73.2%) patients successfully completed the treatment. Conclusions: Our study is one of the largest series in which delayed-type hypersensitivity develops under tuberculosis treatment and the desensitization scheme is recommended. A practical, easy desensitization scheme had been shared in this paper.

Delayed drug hypersensitivity reactions: How p-i transforms pharmacology into immunology.

Delayed drug hypersensitivity reactions (dDHRs) are iatrogenic diseases, which are mostly due to non-covalent interactions of a drug with the immune receptors HLA and/or TCR causing T-cell activation. This is also known as pharmacological interaction with immune receptors or p-i. P-i activation differs from classical antigen-driven immune reactions: a) drug binding induces structural changes in TCR-HLA proteins which make them look like allo-like TCR-HLA-complexes, able to elicit allo-like stimulations of T cells with cytotoxicity and IFNγ production, notably without the involvement of innate immunity; b) drug binding to TCR and/or HLA can increase the affinity of TCR-HLA interactions, which may affect signaling and IL-5 production by CD4+ T cells, and thus contribute to eosinophilia commonly found in dDHRs or induce oligoclonal T cell expansions; c) Both, antigen and p-i stimulations can induce eosinophil- or neutrophil-rich inflammations; but these stimulations should be distinguished as their underlying mechanism and development differ; and d) p-i stimulation can - like graft versus host reactions - result in long-lasting T-cell activations, which can lead to viremia, occasional autoimmunity, or a new syndrome characterized by multiple drug hypersensitivity (MDH). In summary, dDHRs are not allergic reactions but represent peculiar T-cell activations, similar to allo-like stimulations. Understanding and considering the p-i mechanism is needed for preventive measures and optimal treatments of dDHR. In addition, it may help to understand TCR signaling, alloreactivity, and may even open a new way of specific immune stimulations.

Demystifying drug reaction with eosinophilia and systemic symptoms (DRESS): a review of the literature and guidelines for management.

Drug reaction with eosinophilia and systemic symptoms (DRESS) is a severe, adverse drug reaction that is notoriously complex in both its presentation and treatment. Although early diagnosis and cessation of the causative agent are universally accepted as the initial interventions for DRESS, the subsequent management lacks a standardized approach. Historically, systemic steroids have been used as first-line treatment, but there is debate about the optimal dosing and route of administration, and evidence persists on the long-term complications associated with steroid use. Novel treatment approaches with targeted therapy, cyclosporine, intravenous immunoglobulin, and plasmapheresis have been gaining interest as alternative mono- and adjuvant therapies, but their use has yet to be supported by clinical trials. This narrative review provides a summary of the current knowledge of DRESS, with a focus on clinical management. The various mono- and adjuvant therapy options are discussed, with literature-supported suggestions for their optimal use in clinical practice. The risks for relapses, viral reactivation, and long-term complications are also considered. The PubMed and Medline databases were searched for articles on DRESS, published between January 1, 2008, and May 1, 2023. 334 articles met the inclusion criteria. Based on the literature, a DRESS management tool with step-by-step guidance is provided. Further suggestions for management are woven throughout this review, giving clinicians a toolbelt of resources with which to approach diagnosis, treatment, and follow-up.

Retrospective study on penicillin allergy delabeling and evaluation of an antibiotic allergy assessment tool.

BACKGROUND: It has been reported that 95 % of patients labeled as penicillin-allergic may be mislabeled. However, the process of delabeling has not advanced due to a shortage of allergy specialists capable of conducting accurate assessments. To address this issue, The Antibiotics Allergy Assessment Tool (AAAT) has been proposed as a tool to evaluate patients who can be delabeled by non-specialists. OBJECTIVE: This study aims to identify patients who can be delabeled and to evaluate patients who are likely to be delabeled using AAAT. METHODS: Patients admitted to the hospital between January 1, 2017, and December 31, 2021, with documented penicillin allergy labels were included in the study. Patients who demonstrated tolerance to labeled antibiotics or were labeled without explicit allergy declarations were defined as delabeling. Subsequently, patients who did not meet the criteria for delabeling were evaluated for their potential to be delabeled using the AAAT, retrospectively. RESULTS: 530 patients were selected, of which 62 (11.7 %) were delabeled. The AAAT evaluation of the remaining patients indicated that at least an additional 137 (25.8 %) patients could potentially be delabeled. CONCLUSION: The use of AAAT demonstrated the potential to delabel approximately third as many patients without the need for specialist evaluation. To promote broader delabeling efforts in the future, prospective studies should investigate the safety and effectiveness of evaluation tools such as the AAAT.

Clues of HLAs, metabolic SNPs, and epigenetic factors in T cell-mediated drug hypersensitivity reactions.

Drug hypersensitivities are common reactions due to immunologic responses. They are of utmost importance because they may generate severe and fatal outcomes. Some drugs may cause Adverse Drug Reactions (ADRs), such as drug hypersensitivity reactions (DHRs), which can occur due to the interaction of intact drugs or their metabolites with Human Leukocyte Antigens (HLAs) and T cell receptors (TCRs). This type develops over a period of 24-72 h after exposure and is classified as type IV of DHRs. Acute generalized exanthematic pustulosis (AGEP), Stevens-Johnson syndrome (SJS)/toxic epidermal necrolysis (TEN) and drug reaction with eosinophilia and systemic symptoms (DRESS) are types of Severe Cutaneous Adverse Reactions (SCARs). In this review, we aim to discuss the types of ADRs, the mechanisms involved in their development, and the role of immunogenetic factors, such as HLAs in type IV DHRs, single-nucleotide polymorphisms (SNPs), and some epigenetic modifications, e.g., DNA/histone methylation in a variety of genes and their promoters which may predispose subjects to DHRs. In conclusion, development of promising novel in vitro or in vivo diagnostic and prognostic markers is essential for identifying susceptible subjects or providing treatment protocols to work up patients with drug allergies as personalized medicine.

Drug Reaction With Eosinophilia and Systemic Symptoms (DRESS) Syndrome: A Case Report From South India.

Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS) syndrome usually presents two to six weeks after treatment with a drug implicated in this disorder. However, in some cases, it can present more than eight weeks after the initiation of an implicated medication. This is a type 4 drug hypersensitivity reaction in which any internal organ may be involved. While the liver is commonly involved, cardiac involvement is not unheard of. Comorbidities and multiorgan involvement may obscure the diagnosis, and Registry of Severe Cutaneous Adverse Reactions (RegiSCAR) criteria are a useful diagnostic aid. It is best treated by withdrawing the offending agent and administering systemic steroids. Oxidative stress is high in DRESS syndrome. Hepatoprotection is a priority in all patients and yields a better prognosis.

The Immediate and Delayed Maximal Nonirritating Skin Testing Concentrations of ß-Lactam Antibiotics.

BACKGROUND: Maximal skin testing (ST) nonirritant concentrations (NICs) are consistent for penicillin and aminopenicillin among guidelines. However, there is variability among guidelines for maximal ST NICs of cephalosporins. OBJECTIVE: To determine maximal immediate and delayed ST NICs of 15 ß-lactams in ß-lactam-tolerant and ß-lactam-naïve participants. METHODS: We performed a single-center, nonrandomized prospective study between September 2019 and January 2022 in adult participants. Participants received skin prick testing (SPT) and intradermal test (IDT) injections at 6 increasing concentrations of 1 or more ß-lactams. A concentration was considered irritant when more than 5% of participants had a positive test. A positive test was defined as a wheal ≥3 mm compared with negative control accompanied by a ≥5 mm flare for SPT/IDT and induration ≥5 mm with associated erythema at 48 hours for delayed readings (dIDT). Sensitivity analyses using 3 alternative IDT positive criteria were conducted. RESULTS: A total of 747 participants with a median age of 64 (interquartile range: 54-72) years (52% male, 85% White, and 92% non-Hispanic) underwent 20,858 skin tests. All undiluted SPT concentrations were nonirritant. We found the following maximal IDT/dIDT NICs (mg/mL): ampicillin (41.6/125), ampicillin-sulbactam (93.8/187.5), aztreonam (6.3/25), cefazolin (55/165), cefepime (35/140), cefoxitin (45/90), ceftaroline (7.5/15), ceftriaxone (58.3/175), cefuroxime (55/110), ertapenem (16.6/50), imipenem-cilastin (6.3/25), meropenem (8.3/25), nafcillin (31.3/62.5), oxacillin (20.9/83.5), and piperacillin-tazobactam (112.5/225). dIDTs were almost all completely nonirritant close to or at undiluted concentrations. There were no differences when we applied 3 IDT positivity criteria to our raw data. CONCLUSIONS: Our results suggest that SPTs with undiluted stock ß-lactam antibiotic concentrations are nonirritant. Compared with previously published nonirritant concentrations, we propose a 2- to 50-fold increase to the maximal IDT and dIDT NICs of 15 ß-lactam antibiotics. When performing dIDTs, a higher concentration should be used rather than the same IDT concentration.

Risk Stratification of Penicillin Allergy Labeled Children: A Cross-Sectional Study from Jordan.

Background: Implementing allergy testing among children with a reported history of penicillin allergy could be challenging, particularly in developing countries with limited resources. This study screened and risk-stratified the likelihood of true penicillin allergy among children labeled with penicillin allergy in Jordan. Methods: A web-based survey, completed by parents, assessed history, type, and severity of penicillin allergic reactions, including age at diagnosis, symptoms, time to the reaction, reaction's course and resolution, and received medical evaluation/testing. Low-risk allergic symptoms were defined as vomiting, diarrhea, headache, dizziness, itching, rash, cough, or runny nose without evidence of anaphylaxis or severe cutaneous reactions. Results: A total of 530 parents of "penicillin allergy"-labeled children completed the survey. Of these, 86.4% reported allergic reactions to penicillin and 13.6% reported avoidance of penicillin due to family history. Among the former, 52.2% were male, 67.3% were three years old or younger when the reported reaction was established, and 68.3% experienced exclusively low-risk symptoms. Overall, skin rash was the most reported symptom (86.0%). High-risk symptoms were reported in 31.5% of children. About two-thirds (64.0%) of children were reported to have experienced symptoms after the first exposure to penicillin. The most common indication for antibiotic use was a throat infection (63.8%). Asthma comorbidity was significantly higher among high-risk (24.8%) compared low-risk group (11.5%). Conclusion: In Jordan, many parent-reported penicillin allergic reactions seem to be clinically insignificant and unlikely to be verifiable, which can adversely affect patients' care and antimicrobial stewardship. An appropriate clinical history/evaluation is a key step in identifying true immunoglobulin E-mediated allergic reactions and risk stratifying patients for either de-labeling those with obviously non-immune-mediated reactions or identifying candidates for direct oral challenge test.

Sildenafil-induced drug reaction with eosinophilia and systemic symptoms.

Drug reaction with eosinophilia and systemic symptoms (DRESS)/drug-induced hypersensitivity syndrome (DIHS) is a life-threatening, multi-organ adverse drug reaction with a mortality rate of approximately 10 %-20 %. The most common culprit drugs are anticonvulsants, some antibiotics such as dapsone and minocycline, salazosulfapyridine, allopurinol and some antiretroviral molecules such as abacavir and nevirapine. Only one case of DRESS induced by sildenafil has been reported in the literature. Here we report a new case.

Maculopapular rash with multiple drug hypersensitivity to cotrimoxazole, amikacin, piperacillin/tazobactam, and meropenem in a patient with hairy cell leukemia.

We describe a rare case of a 54-year-old female with hairy cell leukemia, who following treatment for neutropenic sepsis, developed an extensive severe maculopapular exanthema with perifollicular hemorrhage. Cladribine, cotrimoxazole, allopurinol, domperidone, amikacin, piperacillin/tazobactam, and meropenem had all been given in the 9 days prior to eruption onset. Three months later, drug patch testing/delayed intradermal testing was positive to cotrimoxazole, trimethoprim, amikacin, piperacillin/tazobactam, and meropenem, with additional evidence of penicillin cross-reactivity. Drug challenge tests were negative to allopurinol and domperidone. She was diagnosed with multiple drug hypersensitivity to cotrimoxazole, amikacin, piperacillin/tazobactam, and meropenem. Multiple drug hypersensitivity is a novel syndrome mainly seen with severe delayed type IV drug eruptions, involving long-lasting strong T-cell reactivity to two or more structurally unrelated drugs.

A diagnostic dilemma: distinguishing a sulfasalazine induced DRESS hypersensitivity syndrome from a CD30 + lymphoma in a young patient.

Drug reaction with eosinophilia and systemic symptoms (DRESS) is a severe hypersensitivity reaction characterized by cutaneous rash, lymphadenopathy, fever, eosinophilia, leukocytosis, and life-threatening organ dysfunctions. We describe the case of a 26 year old patient admitted to the Emergency Department for DRESS syndrome after sulfasalazine treatment for rheumatoid arthritis in the right knee. Whole body computer tomography showed multiple neck, chest, and abdominal lymphadenopathy with splenomegaly, massive ascites and severe hepatic cytolysis. Serology results for Epstein-Barr Virus (EBV), influenza, measles, rubella, hepatitis A and B were negative. The histologic analysis of skin, lymph node and bone marrow biopsies could not indicate a classical Hodgkin's Disease or iatrogenic immunodeficiency/EBV-associated lymphoproliferative disorder (LPD), Hodgkin type. The relatively small caliber of the CD30 + immunoreactive blastoid cells in the lymph nodes suggested reactive immunoblasts rather than Hodgkin cells. The morphologic aspects of the lymph node biopsies with predominance of T-cells were compatible with the diagnosis of a sulfasalazine-induced DRESS syndrome as the patient had a high RegiSCAR score for DRESS. [DRESS Syndrome Foundation: Diagnosis and Treatment. (2023)] The patient's complex clinical course, marked by two hospital admissions, highlights the challenges in diagnosing and managing DRESS. This case underscores the need for individualized care, close patient monitoring, and further research to better understand DRESS's underlying mechanisms and optimal therapeutic strategies.

Optimizing preoperative antibiotic use through improved penicillin allergy documentation.

DISCLAIMER: In an effort to expedite the publication of articles, AJHP is posting manuscripts online as soon as possible after acceptance. Accepted manuscripts have been peer-reviewed and copyedited, but are posted online before technical formatting and author proofing. These manuscripts are not the final version of record and will be replaced with the final article (formatted per AJHP style and proofed by the authors) at a later time. PURPOSE: Penicillin allergy documentation in the electronic health record (EHR) lacks detail with regard to type of reaction, history of reaction, and other tolerated ß-lactams. Because of concern for penicillin allergy cross-reactivity with cefazolin, patients with a reported penicillin allergy are frequently prescribed suboptimal preoperative antibiotics, which have been associated with negative patient outcomes, including increased risk of surgical site infection. The purpose of this study was to increase preoperative use of cefazolin via improvement to the documentation of penicillin allergies in the EHR. METHODS: This single-center, quasi-experimental quality improvement study compared patients with a self-reported penicillin allergy admitted for select elective surgeries before and after implementation of a penicillin allergy questionnaire. The primary outcome was receipt of cefazolin for surgical prophylaxis. Secondary outcomes were the proportion of patients with detailed penicillin allergy documentation, the proportion of patients with surgical site infections occurring within 30 days of surgery, and the proportion of patients who received the full antibiotic dose before the first surgical incision. RESULTS: A total of 100 patients were included in the preintervention group, while 85 patients were included in the postintervention group. Cefazolin use was higher in the postintervention group (13.0% vs 41.2%; P < 0.001). The postintervention group also had a larger proportion of patients with detailed allergy documentation (2.0% vs 50.6%; P < 0.001) and who received the full preoperative antibiotic dose before the first incision (25.0% vs 48.2%; P = 0.001). There was no statistical difference between the groups in the incidence of surgical site infection at 30 days after surgery (3.0% vs 1.2%; P = 0.63). CONCLUSION: Preoperative cefazolin use was higher in patients with a reported penicillin allergy after implementation of a penicillin allergy questionnaire and EHR documentation tool.

DRESS syndrome due to anti-TB drugs: A complex case with successful re-desensitization of group A drugs.

Drug reaction with eosinophilia and systemic symptoms (DRESS) syndrome is a rare, life-threatening adverse reaction caused by certain medications. Clinical findings usually include rash, fever, lymphadenopathy, and eosinophilia, and in some cases, they may affect major organs. This reaction caused by antituberculosis (TB) medication poses a public health risk due to treatment discontinuation, adherence, or success in cure. We present a 23-year-old female patient who developed DRESS syndrome as a result of group A anti-TB drugs (ATDs), an exceedingly rare occurrence. The patient's medication was successfully retrieved using a re-desensitization protocol.

Diagnostic evaluation of hypersensitivity reactions to arylpropionic acid derivatives: a descriptive observational study focusing on clinical characteristics and potential risk factors in children.

BACKGROUND: Arylpropionic acid derivatives (APs) are the main triggers of nonsteroidal anti-inflammatory drug (NSAID) hypersensitivity. Data on clinical patterns and risk factors for AP hypersensitivity in children are quite limited. AIM: To assess the clinical characteristics and potential risk factors for proven AP hypersensitivity in children. METHOD: Patients with a history of AP hypersensitivity were retrospectively assessed using a standardized diagnostic algorithm. Children with confirmed hypersensitivity were defined as selective responders or cross-intolerants based on the result of drug provocation tests and further categorized according to the EAACI/ENDA classification. A multivariable logistic regression analysis was performed to analyze the potential risk factors for proven AP hypersensitivity. RESULTS: A total of 166 patients (51.2% male, median age of six years) with a history of AP hypersensitivity were included. Ibuprofen (89.2%) was the most frequently reported AP in the patients' histories. The reported hypersensitivity of 40 (22.4%) patients was confirmed by diagnostic testing: eight (13.6%) patients with a history of reaction only to APs and 32 (29.9%) patients with a history of reactions to multiple NSAIDs, including chemically unrelated NSAIDs in addition to APs. Five (12.5%) patients were classified as selective responders and 35 (87.5%) were cross-intolerants. Overall, five (12.5%) of the confirmed cases could not be categorized according to the EAACI/ENDA classification. Older age (aOR: 1.11, 95% CI 1.02-1.21, p = 0.015), chronic urticaria as an underlying disease (aOR: 2.87, 95% CI 1.09-7.54, p = 0.033) and a history of anaphylaxis (aOR: 7.84, 95% CI 1.86-33.04, p = 0.005) were related to confirmed AP hypersensitivity. CONCLUSION: Almost a quarter of children and adolescents were confirmed to have AP hypersensitivity. Older age, the presence of chronic urticaria and a history of anaphylaxis were potential risk factors for proven AP hypersensitivity.

HLA-DPB1*05:01 and HLA-A*11:01 Is Associated with Adverse Drug Reactions to Isoniazid and Rifampin for Treatment of Latent Tuberculosis Infection in South Korea.

Background: Screening and treating healthcare workers (HCWs) for latent tuberculosis infection (LTBI) are essential for tuberculosis (TB) infection control. Adverse drug reactions (ADRs) to anti-TB drugs present challenges to patient safety and treatment completion. Objective: This study investigated the association between human leukocyte antigen (HLA) alleles and the risk of ADRs, especially drug hypersensitivity (DHS) and hepatotoxicity, in HCWs with LTBI receiving isoniazid (INH) and rifampin (RIF) therapy. Methods: Korean HCWs with LTBI who received a 3 month INH and RIF regimen were included in this study. HLA genotyping was performed on HCWs who experienced ADRs during treatment, as well as the control group consisted of individuals who did not develop ADRs. Results: Of the 67 patients, 29 (43.2%) experienced ADRs during INH and RIF therapy. The HLA-A*11:01 allele was more frequent in patients with DHS without hepatotoxicity (DSH+/H-) compared to the control group (DHS-/H-) (4/9, 44.4% vs. 3/38, 7.9%; odd ratio [OR], 8.554; 95% confidence interval [CI], 1.415-59.869; p = 0.018). Conversely, HLA-DPB1*05:01 was associated with an increased risk of hepatotoxicity regardless of DHS (10/20, 50% vs. 5/38, 13.2%; OR, 5.323; 95% CI, 1.493-21.518; p = 0.011). In the DHS with hepatotoxicity group (DHS+/H+), HLA-DPB1*05:01 was present in a higher proportion (3/5, 60% vs. 5/38, 13.2%; OR, 8.912; 95% CI, 1.110-92.993; p = 0.037), whereas HLA-A*11:01 was not observed in this group. Conclusions: The HLA-A*11:01 allele was associated with an increased risk of DHS without hepatotoxicity, whereas the HLA-DPB1*05:01 allele was associated with an increased risk of hepatotoxicity.

Challenging dogmas: Intravenous versus oral beta-lactam antibiotic provocation tests.

Background: Drug provocation tests (DPT) are considered the gold standard procedure to ascertain the diagnosis of beta-lactam (BL) allergy. Regarding route of administration, current recommendations prioritize oral challenges, considering them safer, and reserving the intravenous route for drugs for which this is the only formulation. Objective: To compare in terms of tolerance and safety two protocols of BL DPT, using an oral protocol (OR-DPT) and an intravenous protocol (IV-DPT). Methods: A descriptive, retrospective study was performed, including adult patients who underwent IV-DPT or OR-DPT for suspected immediate or delayed hypersensitivity to BL antibiotics, over a period of 4 years (between January 2018 and December 2021). Demographical data, index hypersensivity reactions' characteristics and tolerance to DPT were reviewed. Results: A total of 1036 patients underwent DPT, mean age of 56.8 (standard deviation, SD, 17.8) years, 655 were women (63.2%). Immediate drug hypersensitivity reactions (DHR) had occurred in 564 of patients (54.4%). OR-DPT were performed in 439 (42.4%) and IV-DPT in 597 (57.6%). The frequency of reactions during DPT, regardless of the route used, was low (3.6%): only 16 (3.6%) in OR-DPT and 21 (3.5%) in IV-DPT. From IV-DPT, 16 out 21 DHR during DPT were immediate compared with 4 out of 16 in OR-DPT. Adjusted relative risk of developing a hypersensitivity reaction during IV-DPT versus OR-DPT was 1.13 (95% confidence interval (CI)0.57-2.22). Conclusion: The results suggest that OR-DPT and IV-DPT are both safe procedures when adequately performed. However, IV-DPT protocols showed a higher rate of immediate DHR during DPT probably due to the selection of basal high-risk patients to undergo IV-DPT. In conclusion, IV-DPT may be considered as an option for challenges in drug-allergy studies, entailing a precise administration.

First-Line Antituberculosis Drug Challenge Reactions in Drug Reaction With Eosinophilia and Systemic Symptoms Syndrome in an HIV Endemic Setting.

BACKGROUND: In high HIV prevalence settings, first-line antituberculosis drug (FLTD)-associated drug reaction with eosinophilia and systemic symptoms (DRESS) poses therapeutic challenges. A sequential and additive drug challenge (SADC) of FLTDs best identifies offending drug(s), avoids unnecessary exclusions, and optimizes reinitiation of nonoffending drugs. However, SADC-associated reaction complexities limit its utility. OBJECTIVE: We aimed to describe the characteristics of patients with FLTD-associated DRESS, their treatment-limiting SADC reactions, and related outcomes. METHODS: Patients hospitalized with FLTD-associated DRESS from 2013 to 2023 in a South African tertiary hospital and enrolled (retrospectively or prospectively) in an existing registry were eligible. RESULTS: SADC was undertaken in 41 patients. Overall, 47 classifiable reactions occurred. 34/47 (72%) reactions in 29/41 (71%) patients were treatment-limiting and 12 of 41(29%) patients reinitiated FLTDs uneventfully. Fifteen single and 8 multiple drug reactors were identified. Rifampicin in 13 of 23(57%) reactors was the most common individual offender. Ethambutol was most frequently involved in multiple drug reactors. The median (interquartile range) time to a detectable reaction was 24(12-120) hours, 6 of 34(18%) being immediate (<6 hours). Itch (65%), eosinophilia (56%), fever (41%), atypical lymphocytosis (41%), rash (38%), transaminitis (32%), and facial edema (18%) singly or in combination were the most common features. Three reactions, 1 epidermal necrolysis and 2 liver derangements, were Common Terminology Criteria for Adverse Events grade 4 (life-threatening) events. No predictors of multiple drug reactivity were identified, but multiple reactors were hospitalized significantly longer, 125(100-134) days versus 60(45-80) days. CONCLUSIONS: SADC optimizes FLTD reinitiation. However, timing, clinical presentation, and severity of SADC-associated reactions after FLTD-associated DRESS are markedly heterogeneous. Additionally, multiple drug reactors are a complex group that require longer hospitalization. There are no routine biomarkers available to distinguish true multiple drug hypersensitivity from nonspecific flare-ups and to guide long-term drug avoidance strategies.

Evaluation of accompanying allergic disease in children with proven drug allergies.

Background/aim: Data on the prevalence of allergic diseases in children with proven drug allergies are limited. We aim to evaluate the frequency of allergic comorbidity in children with proven common drug allergies. Materials and methods: Children with drug hypersensitivity confirmed by diagnostic allergy tests at our center between January 2010 and December 2020 were screened retrospectively. Patients with the most common drug allergies (due to antibiotics, nonsteroidal antiinflammatory drugs [NSAIDs], and antiepileptic drugs) were selected for analysis. Age, sex, the culprit drug, initial reaction characteristics, diagnostic test results, and the study physician who diagnosed concomitant allergic diseases were noted. Results: A total of 168 patients (boys, 51.2%) with a median age of 12 years (IQR = 8-16.3) were included in the study. The culprit drug was an antibiotic in 63% (n = 106), NSAID in 25% (n = 42) and anticonvulsant in 11.9 % (n = 20) of the patients. Drug hypersensitivity reactions were immediate in 74.4 % (n = 125) and delayed in 25.6 % (n = 43) of the patients. Seventy-five patients (44.6 %) had at least one allergic disease, most commonly rhinitis (27.3 %, n = 46) or asthma (25 %, n = 42). Fifty-five patients underwent skin prick tests with aeroallergens, producing a positive result in 60% (n = 31). The prevalence of allergic disease was not differing according to the culprit drug. The frequency of developing at least one concomitant allergic disease was 47.2% (n = 50/106) for antibiotic hypersensitivity, 52.4% (n = 22/42) for NSAID hypersensitivity, and 15% (n = 3/20) for anticonvulsant hypersensitivity (p < 0.00).Immediate drug hypersensitivity reactions were more frequent in children who had allergic diseases (80 % vs. 64.5 %; p = 0.027). Conclusion: Nearly half (44.6%) of the children with proven drug hypersensitivity had concomitant allergic diseases and immediate reactions were more common in this group. Children evaluated for drug hypersensitivity should be assessed for other allergic diseases.