Allergic-like Reactions Research Articles

Prevention and management of allergic-like reactions to iodine contrast media: a best practice implementation project.

With the wide application of iodine contrast media (ICM), the occurrence of allergic-like reactions to iodine contrast media (ALR-ICM) has increased. Strategies for the prevention and management of ALR-ICM need to be identified to provide quality care to patients undergoing enhanced computed tomography. The overarching aim of this project was to improve the prevention and management of ALR-ICM at a medical imaging center of a nearly 5,000-bed tertiary hospital in China. This project was guided by the JBI Evidence Implementation Framework, which is grounded in an audit, feedback, and re-audit strategy. A baseline audit was conducted to measure current practices against recommended best practices. Feedback from the audit was used to identify barriers and design strategies to improve practice. A follow-up audit was conducted to measure changes in compliance with best practices. The results revealed a positive change in compliance with best practices. More than 60% compliance with the four audit criteria was observed. The overall ALR-ICM rate decreased from 0.56% to 0.19%, while emergency equipment management dramatically increased from 37.50% to 100%. The smallest improvement was observed for pre-procedure prophylactic treatment of high-risk patients (27.66%). Most audit criteria showed moderate improvements in compliance with best practices. Further testing of this program in more hospitals is needed. http://links.lww.com/IJEBH/A269.

Management of Severe Allergic-Like Contrast Media Reactions: Pitfalls and Strategies, From the AJR Special Series on Contrast Media.

Adverse reactions to contrast media, although uncommon, are often high-acuity events and potentially life-threatening. Nonetheless, these events are treatable, and radiologists may be called on to manage a contrast media reaction. However, because these events are infrequent, they are prone to management errors. This Special Series Review highlights common pitfalls and practical tips for the management of acute contrast media reactions in children and adults. Recognition of frequent management errors and implementation of the mitigation strategies presented can ameliorate risk and improve patient outcomes. These measures include proper training regarding reaction management and medication administration, the prompt use of intramuscular epinephrine autoinjectors whenever a severe allergic-like reaction is suspected, the use of visual aids for quick reference in the setting of a reaction, and the recognition of adverse events that are not allergic-like reactions, which commonly require only supportive care.

Editorial Comment: Recognition and Management of Allergic-Like Reactions to Administered Contrast Media.

Editorial Comment: Recognition and Management of Allergic-Like Reactions to Administered Contrast Media.

Based on UHPLC-Q-TOF-MS and bioinformatics strategies, the potential allergens and mechanisms of allergic reactions caused by Danshen injection were explored.

The aim is to investigate the potential allergens and mechanisms underlying allergic-like reactions induced by Danshen injection (DSI). Utilizing ultra-performance liquid chromatography quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF-MS), metabolomics, and bioinformatics, we identified the key allergens, targets, and metabolic pathways involved in DSI-induced allergic-like reactions, validating binding efficiency through molecular docking and molecular dynamics. A total of 45 compounds were identified within DSI, with 24 compounds exhibiting strong binding activity to the MrgprX2 activation site. DSI was found to cause changes in 89 endogenous metabolites, including arachidonic acid, prostaglandins, and leukotrienes, primarily affecting pathways such as phenylalanine metabolism and arachidonic acid metabolism. The key allergens identified were Cryptotanshinone, Miltipolone, Neocryptotanshinone, Salvianolic acid B, and Isosalvianolic acid C, which primarily trigger allergic-like reactions by regulating upstream signaling targets such as ALOX5, PTGS1, PPARD, and LTB4R. Validation confirmed the high binding affinity and stability between key allergens and targets. These findings indicate that the allergic components in DSI primarily induce allergic-like reactions by modulating the aforementioned signaling targets, activating the AA metabolic pathway, promoting mast cell degranulation, and releasing downstream endogenous inflammatory mediators, subsequently eliciting allergic-like reactions.

The correlation of asparaginase enzyme activity levels after PEG-asparaginase administration with clinical characteristics and adverse effects in Chinese paediatric patients with acute lymphoblastic leukaemia.

Studies on asparaginase enzyme activity (AEA) monitoring in Chinese patients receiving PEG-asparaginase remain limited. We monitored AEA in paediatric patients diagnosed with acute lymphoblastic leukaemia (ALL) and treated according to the Chinese Children's Cancer Group study protocols, CCCG-ALL-2015/CCCG-ALL-2020 protocols. We measured the AEA at days 7 ± 1 and 14 ± 1 and analysed their association with patient characteristics and PEG-asparaginase-related adverse effects (AEs). We measured 2147 samples from 329 patients. Mean AEA levels (interquartile range) were 931 iu/L (654-1174 iu/L) at day 7 ± 1 and 664 iu/L (463-860 iu/L) at day 14 ± 1. The AEA levels were higher in younger children and increased with the cumulative dose numbers. PEG-asparaginase inactivation rate was 19.1%, and the silent inactivation (SI) rate was 12.5%. Nine patients were identified with allergic-like reactions. Hypofibrinogenaemia, hypertriglyceridaemia, pancreatitis and thrombosis were associated with older age, whereas hypoglycaemia was associated with younger age. The risk of hypertriglyceridaemia and hypoglycaemia increased with cumulative dose numbers of PEG-asparaginase. Except for hypofibrinogenaemia, elevated AEA levels did not increase the risk of PEG-asparaginase-related AEs. Drug monitoring can be utilized as guidance for treatment decision-making. Individualizing asparaginase doses do not reduce toxicities. The treatment target of PEG-asparaginase remains to achieve sustained and adequate activity.

Assessment of first-time and repeated acute adverse reactions to gadolinium-based contrast agents in MRI: A retrospective study

PurposeTo identify gadolinium-based contrast agents (GBCAs)-related and patient-related risk factors for acute adverse reactions (AARs), and to examine the incidence and severity of repeated AARs. MethodsThis study retrospectively evaluated all intravenous GBCA injections in MRI studies at a single institution from January 2012 to September 2019. First-time AARs in patients without a past history of AARs and risk factors were assessed using multivariable regression models with generalized estimating equations. For patients with a past history of AAR(s), we evaluated the incidence of repeated AARs using the Fisher's exact test, as well as the severity of these repeated AARs. ResultsFirst-time AARs occurred in 129 of 41,827 GBCA injections (0.31 %; 0.70 % of 18,431 patients). With gadoterate meglumine as the reference, the odds ratio (OR) for allergic-like reactions to three GBCAs ranged from 3.27 to 8.03 (p = 0.012 to <0.001). For chemotoxic reactions, the OR was 3.75 (p = 0.001) for gadoteridol. Outpatients had a lower OR for chemotoxic reactions, while higher ORs were observed in head/neck and breast MRI (p < 0.05). The OR for age was 0.99 (p < 0.05). Patients with a past history of AAR(s) had a 3.6 % incidence of mild repeated AARs for all GBCA, significantly higher than the 0.31 % in first-time AARs (p < 0.001). No effectiveness was found for steroid premedication. ConclusionThe occurrence of first-time AARs was related to the GBCA used and other factors. The incidence of repeated AARs was higher than first-time AARs, though all were mild in severity.

A retrospective study on adverse events of intravenous administration of sulfur hexafluoride microbubbles in abdominal and superficial applications in 83,778 patients.

To investigate the rate of adverse events (AEs) caused by intravenous administration of sulfur hexafluoride microbubbles in abdominal and superficial applications retrospectively and to explore practical measures for prevention and treatment of them. This study enrolled 83,778 contrast-enhanced ultrasound (CEUS) examinations using sulfur hexafluoride microbubbles intravenously performed during 11 years. Age, gender, and target organs of all CEUS patients were recorded. For cases of AEs, their medical history and laboratory results were also collected. The process of AEs was assessed and categorized. Besides, the management of AEs were recorded. Twenty patients had sulfur hexafluoride microbubbles-related AEs. The AE rate was 0.024%. No significant difference was observed between patients with AEs and the whole group for age and sex distribution. All AEs happened in liver examinations. Among them, 7 (35%) were mild, 8 (40%) were moderate, and 5 (25%) were severe. They were categorized into 15 allergic-like reactions and 5 physiologic reactions. The manifestations of mild and moderate AEs mainly include urticaria, chills, and mild hypoxia, which could be eased by simple management. Severe cases had anaphylactic shock, generalized convulsions, and diffuse erythema with hypotension respectively. They need close monitoring and oxygen inhalation with anti-shock and anti-anaphylactic treatment. Most cases started within 30 min and recovered within 1 day. Intravenous administration of sulfur hexafluoride microbubbles in abdominal and superficial applications was safe with rare AEs. AEs were more likely to happen in abdominal applications than superficial ones. A well-designed emergency plan should be available for clinical use of sulfur hexafluoride microbubbles to reduce AEs and to deal with AEs properly. Intravenous administration of sulfur hexafluoride microbubbles in abdominal and superficial applications reported few AEs and could be considered safe but severe AEs are life-threatening. We analyzed the influence factors of AEs and propose some methods for prevention and treatment of them, which can further improve the safety of sulfur hexafluoride microbubbles in clinical practice. • The AE rate of sulfur hexafluoride microbubbles in abdominal and superficial applications was 0.024%. • Patients were more likely to have AEs in abdominal applications than superficial ones. • Severe AEs are life-threatening and need prompt identification and treatment. • We summarized some detailed suggestions for clinical prevention and treatment of AEs.

Continuous PEGasparaginase Dosing Reduces Hypersensitivity Reactions in Pediatric ALL: A Dutch Childhood Oncology Group ALL11 Randomized Trial.

The primary objective of this randomized study was to determine whether a continuous dosing schedule (without the asparaginase-free interval) would result in less hypersensitivity reactions to PEGasparaginase (PEGasp) compared with the standard noncontinuous dosing schedule. Eight hundred eighteen patients (age 1-18 years) with ALL were enrolled in the Dutch Childhood Oncology Group-ALL11 protocol and received PEGasp. Three hundred twelve patients stratified in the medium-risk arm were randomly assigned to receive 14 individualized PEGasp doses once every two weeks in either a noncontinuous or continuous schedule after the first three doses in induction (EudraCT: 2012-000067-25). Hypersensitivity reactions were defined as allergies, allergic-like reactions, and silent inactivation. Secondary end points were other asparaginase-related toxicities, asparaginase activity and antibody levels, and outcome. During induction, 27 of 818 patients (3.3%) experienced hypersensitivity reactions. After random assignment, 4 of 155 (2.6%) in the continuous treatment arm versus 17 of 157 (10.8%) patients in the noncontinuous treatment arm had hypersensitivity reactions (P < .01), of which two (1.3%) versus 13 (8.3%) were inactivating reactions (P < .01). The occurrence of inactivating hypersensitivity reactions was seven times lower in the continuous arm (odds ratio, 0.15 [0.032-0.653]). In addition, antibody levels were significantly lower in the continuous arm (P < .01). With exception of a lower incidence of increased amylase in the continuous arm, there were no significant differences in total number of asparaginase-associated toxicities between arms. However, the timing of the toxicities was associated with the timing of the asparaginase administrations. No difference in 5-year cumulative incidence of relapse, death, or disease-free survival was found between both treatment arms. A continuous dosing schedule of PEGasp is an effective approach to prevent antibody formation and inactivating hypersensitivity reactions. The continuous PEGasp schedule did not increase toxicity and did not affect the efficacy of the therapy.

Influence of Contrast Media Temperature and Concentration on Patient Comfort and Safety in Computed Tomography: CATCHY II Trial.

Previous research on the necessity to reduce the viscosity of contrast media (CM) by either prewarming CM before injection during computed tomography (CT) or by using less concentrated CM has yielded conflicting results. In addition, there is limited evidence on patient comfort. The aim of the study was to examine if prewarming CM, with varying CM concentrations, is superior to CM at room temperature, with respect to patient comfort and safety in CT. All elective patients scheduled for contrast-enhanced CT scans at Maastricht University Medical Center+ between October 27, 2021 and October 31, 2022 were eligible for inclusion when a questionnaire evaluating patient comfort was completed. This 1-year period was divided into 4 intervals (4 groups): group 1 (370 mg I/mL, 37°C), group 2 (370 mg I/mL, room temperature), group 3 (300 mg I/mL, 37°C), and group 4 (300 mg I/mL, room temperature). All CT scans were performed using state of the art equipment (Siemens Healthineers; SOMATOM Force and SOMATOM Definition AS, Forchheim, Germany). Contrast media injections were performed using a dual-head power injector (Stellant; Bayer Healthcare, Berlin, Germany) and individualized to body weight and/or tube voltage, depending on the CM protocols. After the CT scan, patients completed a questionnaire covering the primary outcomes comfort, pain, and adverse events such as feelings of heat, nausea, vomiting, itchiness, urticaria, difficulty breathing, dizziness, goosebumps, or an odd taste. Technicians were asked to report any adverse events, including extravasation and allergic-like reactions. The secondary outcome involved attenuation (in Hounsfield unit, HU), which was evaluated by assessing the HU of the coronary arteries for vascular CT, and liver enhancement in portal venous CT. The Kruskal-Wallis test was used for continuous scale outcomes and χ 2 tests for examining adverse events. Results showed no significant differences examining comfort score ( P = 0.054), pain sensation ( P = 0.469), extravasation ( P = 0.542), or allergic-like reaction ( P = 0.253). Significant differences among the 4 groups were found with respect to heat sensation and dizziness ( P = 0.005 and P = 0.047, respectively), showing small effect sizes. All other adverse effects showed no significant results. No significant differences were observed in coronary attenuation among the 4 groups in coronary CT angiography ( P = 0.113). When analyzing attenuation in portal venous CT scans, significant differences were found among the 4 groups ( P = 0.008). Administrating prewarmed CM is nonsuperior compared with CM at room temperature in relation to patient comfort and safety, regardless of CM concentration. These findings suggest that prewarming CM before usage is unnecessary, which will improve the efficiency of daily clinical workflow and brings environmentally friendly benefits.

Changing Gadolinium-Based Contrast Agents to Prevent Recurrent Acute Adverse Drug Reactions: 6-Year Cohort Study Using Propensity Score Matching.

To determine the preventive effect of changing gadolinium-based contrast agents (GBCAs) to reduce the recurrence of GBCA-associated acute adverse drug reactions (ADRs). This retrospective, observational, single-center study-conducted between January 2016 and December 2021-included 238743 consecutive GBCA-enhanced MRI examinations. We focused on a subgroup of patients who experienced acute GBCA-associated ADRs during any of these examinations and subsequently underwent follow-up GBCA-enhanced MRI examinations up until July 2023. The follow-up examinations involved either the same (non-change group) or different (change group) GBCAs compared to the ones that initially caused the acute ADR. Baseline participant characteristics, generic profile of the GBCAs, administration of premedication, history of prior ADR to iodinated contrast media, and symptoms of GBCA-associated acute ADRs were retrospectively analyzed. Multivariable logistic regression with generalized estimating equations and propensity score matching were used. A total of 1042 instances of acute ADRs (0.44%; 95% confidence interval [CI]: 0.41%-0.46%) were reported. Three-hundred and seventy-three patients underwent GBCA-enhanced MRI examinations after experiencing GBCA-associated acute ADRs within the study period; 31.9% (119/373) reexperienced acute ADRs at any of the follow-up examinations. The ADR recurrence was significantly lower in the GBCA change group than in the non-change group according to multivariable logistic regression (adjusted odds ratio [OR]: 0.35; 95% CI: 0.13-0.90; P = 0.03) and analysis with propensity score matching (14.3% [6/42] vs. 36.9% [31/84], respectively; OR: 0.32, 95% CI: 0.11-0.94; P = 0.04). A history of an ADR to iodinated contrast media (OR: 1.14, 95% CI: 0.68-1.90; P = 0.62) and premedication (adjusted OR: 2.09, 95% CI: 0.93-4.68; P = 0.07) were not significantly associated with GBCA-associated acute ADR recurrence. A separate analysis for recurrent allergic-like hypersensitivity reactions demonstrated similar results (adjusted OR: 0.20, 95% CI: 0.06-0.65; P < 0.01). Changing GBCAs may reduce the risk of GBCA-associated acute ADR recurrence.

Acute Adverse Events After Iodinated Contrast Agent Administration of 359,977 Injections: A Single-Center Retrospective Study.

To assess the effects of patient variables, examination variables, and seasonality on allergic-like and physiologic reactions to iodinated contrast material (ICM). All ICM-enhanced computed tomography (CT) examinations performed from June 1, 2009, to May 9, 2017, at our institution were included. Reactions were identified and categorized as allergic-like or physiologic and mild, moderate, or severe. The effect of patient and examination variables on reactions was evaluated by logistic regression models. A total of 359,977 CT examinations performed on 176,886 unique patients were included. A total of 1150 allergic-like reactions (0.32%; 19 severe [0.005%]) and 679 physiologic reactions (0.19%; 3 severe [0.0008%]) occurred. On multivariable analysis, iopromide had higher rates of reactions compared with iohexol (allergic-like reactions: odds ratio [OR], 3.07 [95% CI, 2.37 to 3.98], P<.0001; physiologic reactions: OR, 2.60 [1.92 to 3.52], P<.0001). Non-White patients had higher rates of reactions compared with White patients (allergic-like reactions: OR, 1.77 [1.36-2.30], P<.0001; physiologic reactions: OR, 1.76 [1.27-2.42], P=.0006). Patient age, sex, prior ICM reaction, ICM dose, CT location, and CT type were also significantly associated with reactions. No significant seasonality trend was observed (P=.07 and .80). Non-White patients and patients administered iopromide had higher rates of acute reactions compared with White patients and patients administered iohexol. Younger patients (<50 years vs 51 to 60 years), female sex, history of ICM allergy or other allergies, ICM dose, and contrast-enhanced CT location and type also correlated with higher acute reaction rates.

Risk management and risk communication of an illegal use of sulphites in meat preparations

Abstract This paper presents a case study on the management of a food fraud associated with health risks: the illegal use of sulphites in meat preparations and minced meat in Slovenia in 2019. The purpose is to highlight the shortcomings of existing systems for ensuring food safety in case of food frauds and highlight challenges for improvements. Sulphites are food additives but also have significant allergenic potential, hence they may cause serious reactions in sensitized consumers. Labelling of foods treated with sulphites is mandatory, and their use in meat and meat preparations in Europe is not allowed. However, certain food business operators may intentionally add sulphites into meat preparations to improve the sensory properties; besides being a food fraud, this exposes unaware consumers to health risks. The case started with the notification of an allergic-like reaction by a consumer following the consumption of a meat product. While the public authorities reacted by intensifying controls on markets and retailers, the analysis of risk management and risk communication aspects showed a number of shortcomings: slow response time; lack of recall of sulphite-treated meat products and of an in-depth risk assessment. The evaluation of this case study identified violations of food law regulations and consumer protection legislation. Effective risk management requires an interdisciplinary approach, integrating timely and targeted official control and risk communication throughout the food chain to protect consumers from unfair practices. Consistent, effective, and transparent communication among all actors who share responsibility in ensuring food safety is necessary to achieve improvements. This serious case of food fraud with actual risks to consumer health provided an opportunity for lessons to be learnt regarding managing health hazards from intervention to prevention.

Implementation of Continuous Pegasparaginase Dosing without an Asparaginase-Free Interval Reduces Hypersensitivity in Children with Newly Diagnosed Acute Lymphoblastic Leukemia: Results of the DCOG ALL11 Pegasparaginase Randomization

Background: Asparaginase is key in the treatment of pediatric acute lymphoblastic leukemia (ALL). Hypersensitivity is one of its major side effects and hamper its use. Most hypersensitivity reactions occur after an asparaginase-free interval, as neutralizing anti-drug antibodies increase during these intervals. Thus we hypothesized that a continuous PEGasparaginase dosing schedule (without an asparaginase-free interval) would result in less hypersensitivity to PEGasparaginase compared to the standard non-continuous PEGasparaginase dosing schedule. Methods: Medium risk (MR) patients (aged 1-18 yrs) with ALL enrolled in the DCOG ALL11 protocol, were randomized to receive 14 individualized PEGasparaginase doses after an asparaginase-free interval of 3 months or to continue PEGasparaginase treatment following the first 3 doses in induction (EudraCT:2012-000067-25; Dutch Trial Register NL3227). Hypersensitivity included allergies, allergic-like reactions, and silent inactivations, where inactivating hypersensitivity reactions comprised the sum of allergies and silent inactivations. Secondary endpoints included other asparaginase-related adverse event (AEs) (CTCAE &amp;gt;grade 3), such as febrile neutropenia, infection, a thromboembolic event, pancreatitis, and avascular necrosis, as well as antibody levels and treatment outcome. Cumulative incidence of relapse (CIR), cumulative incidence of death (CID) in CR1 and disease-free survival (DFS) were compared between both treatment arms. Results: 312 MR patients were randomized to receive PEGasparaginase in a continuous (n=155) and non-continuous (n=157) dosing schedule. Hypersensitivity reactions occurred in 4 out of 155 (2.6%) patients in the continuous treatment arm versus 17 out of 157 (10.8%) patients in the non-continuous treatment arm (P&amp;lt;0.01), of which 2 (1.3%) versus 13 (8.3%) were inactivating reactions (Figure 1; P&amp;lt;0.01). Patients in de continuous treatment arm were significantly less likely to get an inactivating hypersensitivity reaction (odds ratio: 0.15 (0.032-0.653), P=0.012). Antibody levels were significantly lower in the continuous arm compared to the non-continuous arm (P&amp;lt;0.01). Without the asparaginase-free interval, the antibody levels slightly increased by 1.1-fold between dose 3 and 4 whereas antibody levels in the non-continuous arm increased by 2.5-fold during the asparaginase-free interval. We did not find any significant differences in the total number of asparaginase-associated AEs between the treatment arms (Figure 1). However, the generalized Poisson model analysis revealed that the occurrence of specific AEs, such as a thromboembolic event and pancreatitis, was influenced by both treatment phase and arm. These correlations can be attributed to the timing of asparaginase administrations, since at start of randomization asparaginase treatment was interrupted in the non-continuous arm but uninterrupted in the continuous arm. Consequently, thromboembolic events and pancreatitis occurred more frequently at the beginning of randomization in the continuous arm compared to the non-continuous arm (Table 1). This pattern reversed when the non-continuous arm resumed asparaginase treatment after the asparaginase-free period, while the continuous arm concluded their treatment. The occurrence of infections was not associated with treatment phase and treatment arm. The median duration of treatment phases was comparable between the two arms, with the exception of a longer duration of protocol M in the continuous versus non-continuous arm (median 10.3 versus 9.4 weeks respectively instead of the planned 9 weeks; P&amp;lt;0.01) Estimated median follow-up time was 57.2 months (95%-CI 51.9-61.3). The 5-yr CIR, CID in CR1 and DFS were 5.6% (SE 2.1%), 1.9% (SE 1.1%) and 91.9% (SE 2.4%) for continuous treatment vs 4.0% (SE 1.8%), 0.6% (SE 0.6%) and 95.3% (SE 1.9%) for non-continuous treatment (P=0.710; P=0.308; P=0.289), respectively. Conclusion: A continuous dosing schedule of PEGasparaginase resulted in a 7 times lower incidence of inactivating hypersensitivity reactions and lower anti-drug antibody levels compared with a non-continuous dosing schedule with an asparaginase-free interval. The continuous schedule of asparaginase treatment did not increase toxicity but changed the timing of toxicities and did not affect the efficacy of the therapy.

Reducing Gadolinium Contrast With Artificial Intelligence.

Gadolinium contrast is an important agent in magnetic resonance imaging (MRI), particularly in neuroimaging where it can help identify blood-brain barrier breakdown from an inflammatory, infectious, or neoplastic process. However, gadolinium contrast has several drawbacks, including nephrogenic systemic fibrosis, gadolinium deposition in the brain and bones, and allergic-like reactions. As computer hardware and technology continues to evolve, machine learning has become a possible solution for eliminating or reducing the dose of gadolinium contrast. This review summarizes the clinical uses of gadolinium contrast, the risks of gadolinium contrast, and state-of-the-art machine learning methods that have been applied to reduce or eliminate gadolinium contrast administration, as well as their current limitations, with a focus on neuroimaging applications. EVIDENCE LEVEL: 3 TECHNICAL EFFICACY: Stage 1.

Update on Gadolinium-Based Contrast Agent Safety, From the AJR Special Series on Contrast Media.

Since its introduction more than 35 years ago, gadolinium-enhanced MRI has fundamentally changed medical practice. Although extraordinarily safe, gadolinium-based contrast agents (GBCAs) may have side effects. Four distinct safety considerations include acute allergiclike reactions, nephrogenic systemic fibrosis (NSF), gadolinium deposition, and symptoms associated with gadolinium exposure. Acute reactions after GBCA administration are uncommon-far less than with iodinated contrast agents-and, although rare, serious reactions can occur. NSF is a rare but serious sclerodermalike condition occurring in patients with kidney failure after exposure to American College of Radiology (ACR) group I GBCAs. Group II and III GBCAs are considered lower risk, and, through their use, NSF has largely been eliminated. Unrelated to NSF, retention of trace amounts of gadolinium in the brain and other organs has been recognized for over a decade. Deposition occurs with all agents, although linear agents appear to deposit more than macrocyclic agents. Importantly, to date, no data show any adverse biologic or clinical effects from gadolinium deposition, even with normal kidney function. This article summarizes the latest safety evidence of commercially available GBCAs with a focus on new agents, discusses updates to the ACR NSF GBCA safety classifications, and describes approaches for strengthening the evidence needed for regulatory decisions.

Pseudo-Allergies in the Emergency Department: A Common Misdiagnosis of Hypersensitivity Type 1 Allergic Reaction.

Type-1 hypersensitivity reaction represents an acute IgE-mediated reaction that can cause life-threatening conditions, such as anaphylactic shock, angioedema, and airway obstruction. Other reactions that can mimic type-1 hypersensitivity reactions include IgE-independentmast cell degranulation, bradykinin-mediated reactions, leukotrienes-mediated reactions, and pseudo-allergies. We use the term pseudo-allergy in this article for histamine-mediated reactions that are mast cell-independent. We did not discuss pseudo-allergic reactions that are not acute or life-threatening, such as celiac disease, Heiner's syndrome, eosinophilic esophagitis, and food protein-induced enterocolitis in our article because the emergency department is not the primary location to diagnose or treat these reactions. Herein, we present some allergic-like reactions that can be life-threatening, such as scombroid food poisoning (SFP), bradykinin-induced angioedema, IgE-independent angioedema, opioid-induced angioedema, and non-steroidal anti-inflammatory drug (NSAID)-induced hypersensitivity and angioedema. These reactions may have different treatments based on their mechanism of reaction. Histamine-mediated reactions, such as SFP, histamine-mediated angioedema, and mast cell degranulation induced by NSAIDs, and opioids can be treated with antihistamines, epinephrine, and corticosteroids. Bradykinin-induced angioedema, including hereditary angioedema and acquired angioedema, can be treated with fresh frozen plasma. Hereditary angioedema can be treated withmany FDA-approved targeted medications, such asplasma-derived C1-INH,plasma kallikrein inhibitor (Ecallantide), and selective bradykinin-2 receptor antagonist (Icatibant).However, these targeted agents are not well-studied enough to be used for acquired angioedema.It is crucial for emergency medicine physicians to be familiar with and predict these reactions to prevent misdiagnosis, be prepared to treat these life-threatening conditions appropriately without delay and eliminate patients' exposure to any unnecessary investigations or treatments.

Relationship Between Patient-Friendly Audiovisual Systems and MRI Contrast Agent to Adverse Reactions.

Patient-friendly audiovisual (AV) systems in head MRI examinations can potentially reduce patient anxiety and contrast-enhanced MRI (CE-MRI) adverse reactions to gadolinium. To evaluate whether a patient-friendly AV system reduces the rate of adverse reactions to gadolinium-based contrast agents. Retrospective. Four thousand eight hundred thirty-two outpatients (2462 female) attending for clinical CE-MRI studies. (Gadoteridol: 1971, Meglumine gadoterate: 2733, Gadobutrol: 128.) FIELD STRENGTH/SEQUENCE: Routine CE-MRI of head and neck using a 1.5 T or 3 T scanner with or without a patient-friendly AV system. One thousand one hundred fifty-nine patients were scanned on MRI machines equipped with patient-friendly AV systems (AV group) and 3673 on MRI machines without AV systems (control group). Adverse reaction rate and symptoms were reviewed by referring to the system database and electronic medical records and compared between the two groups. Adverse reactions were defined as physiological reactions, such as vomiting and allergic-like reactions, such as urticaria, occurring within 1 hour of contrast injection. We compare patient backgrounds, adverse reaction rate, adverse reactions symptoms and the severity between the two groups. Adverse reaction rate with and without a patient-friendly AV system were compared using Fisher's exact test. The relationship between patient-friendly AV systems and the occurrence of adverse reactions was evaluated with logistic regression. Statistical significance was set at P < 0.05. Of the 4832 patients enrolled, 65 (1.35%) experienced adverse reactions. The most common adverse reactions in both groups were urticaria and pruritus. Adverse reaction rate was significantly lower in the AV group than in the control group (0.7% vs. 1.6%). No significant difference was observed in the severity (P = 1.000) of adverse reactions and symptoms (allergic-like reaction: P = 0.08, physiologic reaction: P = 1.000) between the two groups. The patient-friendly AV system significantly reduce adverse reaction occurrence to gadolinium-based contrast agents. 4 TECHNICAL EFFICACY: Stage 1.

Hypersensitivity Reactions to Native E. coli L-asparaginase in Children With Acute Lymphoblastic Leukemia Treated in Trial ALL-BFM 2000: Impact of Treatment Schedule and Type of Glucocorticoid in Induction.

Hypersensitivity Reactions to Native E. coli L-asparaginase in Children With Acute Lymphoblastic Leukemia Treated in Trial ALL-BFM 2000: Impact of Treatment Schedule and Type of Glucocorticoid in Induction.

Clinical Follow-up in Patients With Moderate or Severe Allergic-Like Reactions to Iodinated Contrast Material

ObjectiveTo examine follow-up care in patients with a history of acute allergic-like reaction to iodinated contrast material (ICM), including subsequent imaging management, allergy consultation, and repeat ICM exposure and reactions. MethodsAll patients who had a moderate or severe acute allergic-like reaction to ICM after contrast-enhanced CT (CECT) examination from June 1, 2009, to January 1, 2022, at our institution were included. Chart review was performed to determine (1) whether subsequent imaging was not performed or was altered in these patients, (2) whether the patient underwent a subsequent CECT examination, and (3) whether the patient had an allergist consultation. ResultsA total of 251 patients were identified. One-third of patients (90 of 251, 36%) had at least one change to their subsequent imaging management due to their reaction, including performing an unenhanced CT (62 of 251, 25%) or MRI (22 of 251, 8.8%) instead of a CECT or not performing a CECT when otherwise clinically indicated (20 of 251, 8.0%). Patients with a prior severe reaction were more likely to have a change in management than patients with a prior moderate reaction (severe: 22 of 32 [69%] versus moderate: 68 of 219 [31%], P < .0001). Only 17 patients (6.8%) had an allergy consult for their ICM reaction. A total of 90 patients underwent 274 subsequent CECT examinations. Repeat allergic-like reactions were observed in one quarter of patients (24 of 90, 27%) and a tenth of CECT examinations (29 of 274, 11%). DiscussionOne-third of patients with a history of a moderate or severe allergic-like reaction to ICM had their subsequent imaging care modified due to their reaction.

Good Immunogenicity of Delayed Second Dose of BNT162b2 Vaccine in Individuals with Acute Allergic-like Reactions after the First Dose

We assessed SARS-CoV-2 anti-spike immunoglobulin G (anti-S-IgG) levels among healthcare workers (HCWs) after BNT162b2 vaccination. The anti-S-IgG titers of study participants were measured every three months, a week before, and three weeks after each vaccination. This study compared the short-term immune response to the second vaccination in four HCWs who received the first two doses six months apart (due to acute allergic-like adverse events after the first dose), with that of six HCWs who received the first two doses three weeks apart, according to the standard schedule. The four HCWs who experienced acute allergic-like adverse events after the first vaccination took antihistamines before the second vaccination. None of them experienced an allergic-like reaction after the second vaccination, and the short-term immune response to the second vaccination was similar in both groups.