A prospective, multicenter, three-cohort study evaluating contrast-induced acute kidney injury (CI-AKI) in patients with cirrhosis.

BACKGROUND & AIMS: Nephrotoxicity of intravenous iodinated contrast media (ICM) in cirrhosis is still a debated issue, due to scarce, low-quality and conflicting evidence. This study aims to evaluate the incidence and predisposing factors of acute kidney injury (AKI) in patients with cirrhosis undergoing contrast-enhanced computed tomography (CECT). METHODS: We performed a prospective, multicenter, cohort study including 444 inpatients, 148 with cirrhosis (cohort 1) and 163 without cirrhosis (cohort 3) undergoing CECT and 133 with cirrhosis (cohort 2) unexposed to ICM. Kidney function parameters were assessed at T0, 48-72 h (T1), 5 and 7 days after CECT/enrollment. Urinary neutrophil gelatinase-associated lipocalin (U-NGAL) was measured in 50 consecutive patients from cohort 1 and 50 from cohort 2 as an early biomarker of tubular damage. RESULTS: AKI incidence was not significantly increased in patients with cirrhosis undergoing CECT (4.8%, 1.5%, 2.5% in cohorts 1, 2, 3 respectively, p = n.s.). Most AKI cases were mild and transient. The presence of concomitant infections was the only independent predictive factor of contrast-induced AKI (odds ratio 22.18; 95% CI 2.87-171.22; p = 0.003). No significant modifications of U-NGAL between T0 and T1 were detected, neither in cohort 1 nor in cohort 2 (median ΔU-NGAL: +0.2 [-7.6 to +5.5] ng/ml, +0.0 [-6.8 to +9.5] ng/ml, respectively [p = 0.682]). CONCLUSIONS: AKI risk after CECT in cirrhosis is low and not significantly different from that of the general population or of the cirrhotic population unexposed to ICM. It mostly consists of mild and rapidly resolving episodes of renal dysfunction and it is not associated with tubular kidney injury. Patients with ongoing infections appear to be the only ones at higher risk of AKI. IMPACT AND IMPLICATIONS: Nephrotoxicity due to intravenous iodinated contrast media (ICM) in patients with cirrhosis is still a debated issue, as the available evidence is limited and based on very heterogeneous studies, often conducted on small and retrospective cohorts. In this prospective three-cohort study we found that intravenous administration of ICM was associated with a low risk of AKI, similar to that of the general population and to that of patients with cirrhosis unexposed to ICM. Patients with ongoing infections were the only ones to have a significantly increased risk of contrast-induced AKI. Therefore, the actual recommendations of performing contrast imaging studies cautiously in cirrhosis do not seem to be reasonable anymore, with the exception of infected patients, who have a significantly higher risk of contrast-induced AKI.

Neurodevelopmental outcomes of school-age children conceived after hysterosalpingography with oil-based or water-based iodinated contrast: long-term follow-up of a nationwide randomized controlled trial.

STUDY QUESTION: Does preconceptional exposure to oil-based iodinated contrast media during hysterosalpingography (HSG) impact children's neurodevelopment compared with exposure to water-based alternatives? SUMMARY ANSWER: Our study found no large-sized effects for neurodevelopment in children with preconceptional exposure to oil-based iodinated contrast media during HSG compared with water-based alternatives. WHAT IS KNOWN ALREADY: HSG is widely used as a diagnostic tool in the female fertility work-up. Tubal flushing with oil-based iodinated contrast has been shown to enhance fertility outcomes in couples with unexplained infertility, increasing the chances of pregnancy and live birth compared with water-based alternatives. However, oil-based contrast contains higher doses of iodine and has a longer half-life, and concerns exist that iodinated contrast media can affect women's iodine status and cause temporary (sub)clinical hypothyroidism in mothers and/or foetuses. Considering that thyroid hormones are vital to embryonal and foetal brain development, oil-based contrast media use could increase the risk of impaired neurodevelopment in children conceived shortly after HSG. Here we examine neurodevelopmental outcomes in school-aged children conceived after HSG. STUDY DESIGN, SIZE, DURATION: This is a long-term follow-up of the H2Oil trial in which oil-based or water-based contrast was used during HSG (Netherlands; 2012-2014; NTR3270). Of 369 children born <6 months after HSG in the study, we contacted the mothers of 140 children who gave consent to be contacted for follow-up. The follow-up study took place from January to July 2022 (NCT05168228). PARTICIPANTS/MATERIALS, SETTINGS, METHODS: The study included 69 children aged 6-9 years who were conceived after HSG with oil-based (n = 42) or water-based contrast (n = 27). The assessments targeted intelligence (Wechsler Intelligence Scale for Children), neurocognitive outcomes (computerized neurocognitive tests), behavioural functioning (parent and teacher questionnaires), and academic performance. Linear regression models, adjusted for age, sex, and parental educational attainment were employed to compare groups. MAIN RESULTS AND THE ROLE OF CHANCE: School-aged children born to mothers after oil-based contrast HSG did not significantly differ from children born to mothers after water-based contrast HSG, in regards to intelligence, neurocognitive functioning, behavioural functioning, or academic performance, with the exception of better performance for visuomotor integration functions in children exposed to oil-based contrast preconception. After exploratory correction for multiple comparisons, none of the group differences was statistically significant. LIMITATIONS, REASONS FOR CAUTION: The small sample size of this follow-up study limited statistical power. This study provides evidence for the absence of large-sized differences between preconceptional exposure to the two contrast media types but does not rule out more subtle effects on neurodevelopment compared to naturally conceived children without preconceptional exposure to HSG. WIDER IMPLICATIONS OF THE FINDINGS: This study contributes to our knowledge about the long-term effects of different types of iodinated contrast media used in fertility work-up, indicating that choosing oil-based over water-based iodinated contrast media is unlikely to have major effect on the long-term neurodevelopmental outcomes of children conceived shortly after HSG. However, further research should focus on the overall safety of iodine exposure during HSG, comparing children conceived after HSG to those conceived naturally as both types of contrast contain high amounts of iodine. STUDY FUNDING/COMPETING INTEREST(S): The original H2Oil randomized controlled trial was an investigator-initiated study that was funded by the two academic hospitals now merged into the Amsterdam University Medical Centre. The current follow-up study (Neuro-H2Oil) is funded through a research grant awarded to the authors by the Amsterdam Reproduction & Development (AR&D) research institute. S.K. is funded by a AMC MD/PhD Scholarship from the Amsterdam UMC. S.K. reports holding voluntary roles in the civil society organizations Universities Allied for Essential Medicines and People's Health Movement. V.M. reports receiving travel and speaker fees as well as research grants from Guerbet, Merck and Ferring. K.D. reports receiving travel and speaker fees as well as research grants from Guerbet. BWM is supported by a NHMRC Investigator grant (GNT1176437) and reports consultancy, travel support and research funding from Merck, consultancy for Organon and Norgine, and holding stock from ObsEva. The other authors report no conflict of interest. TRIAL REGISTRATION NUMBER: NCT05168228.

Safety of non-ionic contrast media in CT examinations for out-patients: retrospective multicenter analysis of 473,482 patients.

OBJECTIVES: This study aimed to explore the incidence of and potential risk factors for adverse drug reactions (ADRs) after non-ionic iodinated contrast media (NICM) administration for CT exams in out-patient settings in China. MATERIALS AND METHODS: A total of 473,482 out-patients who underwent intravenous NICM between January 1st, 2017, and Dec 31st, 2021, were retrospectively enrolled from three institutions. The occurrence of ADRs and clinical information were recorded. Chi-square test, Poisson regression, and logistic regression analyses were used to evaluate potential ADR risk factors and correlation with demographics, season, and NICM type. RESULTS: Among the 473,482 patients (mean age 55.22 ± 14.85; 253,499 male) who received intravenous NICM, the overall ADR incidence was 0.110% (522 of 473,482), with 0.099% acute-related drug reactions (469 of 473,482) and 0.0004% serious ADRs (two of 473,482). Iopromide was associated with a higher risk of acute ADRs. Late ADRs were more frequently observed with iodixanol 320. Multi-level logistic regression of patients with acute ADRs and a control group (matched 1:1 for age, gender, NICM, prescriber department, and institution) showed that summer (adjusted OR = 1.579; p = 0.035) and autumn (adjusted OR = 1.925; p < 0.001) were risk factors of acute ADRs. However, underlying disease and scanned body area were not related to a higher ADR incidence. CONCLUSION: The use of NICM for out-patients is in general safe with a low ADR incidence. The type of contrast medium (iopromide) and the seasons (summer and autumn) were associated with a higher risk of acute ADRs. Late ADRs were more often observed with iodixanol. CLINICAL RELEVANCE STATEMENT: In comparison to in-patients, out-patients may be exposed to higher risk due to a lack of extensive risk screening, less nursing care, and higher throughput pressure. Safety data about NICM from a large population may complement guidelines and avoid ambiguity. KEY POINTS: • The incidence and risk factors for adverse events after using non-ionic iodinated contrast media are complex in out-patients. • Non-ionic iodinated contrast media are safe for out-patients and the overall incidence of adverse drug reactions was 0.110%. • There is a higher risk of acute adverse drug reactions in summer and autumn.

Trace Cu(II) as an Efficient Electron-Transfer Shuttle for Reductive Deiodination of Refractory Iodinated Contrast Media Compounds.

Iodinated contrast media compounds (ICMs) are intensively applied in medical diagnostic radiology and have received wide environmental concerns due to formation potential of iodinated disinfection byproducts. Conventional water/wastewater treatment processes cannot effectively remove ICMs; reducing their total organic iodine concentration is even more difficult. The source control or elimination of ICMs thus becomes necessary. We report here that the refractory ICMs (5 µM) can be efficiently deiodinated by ascorbate/ascorbic acid (AA) (200 µM) coupled with a trace amount of Cu(II) (5 µM) through catalytic reduction but not oxidation, contrary to the conventional concept of AA/Cu(II) coupling, which produces reactive oxygen species. Taking diatrizoate (DTZ, a refractory ICM) as an example, the coupling completely deiodinated DTZ without destroying its molecular structure. High-performance liquid chromatography inductively coupled plasma mass spectrometry analysis revealed that ternary complexes form between Cu(II), ascorbate, and the anilide moiety of DTZ. Cu(II) in the ternary complex works as an efficient electron-transfer shuttle to convey electrons from ascorbate to the target compound, inducing sequential and complete deiodination. Both DTZ and the nonionic ICMs can be effectively deiodinated even in human urine. Thus, AA coupled with trace Cu(II) could be potentially useful for the source elimination of organic iodine of ICMs.

In-silico mechanistic analysis of adsorption of Iodinated Contrast Media agents on graphene surface.

The study aims at assessing the potential of graphene-based adsorbents to reduce environmental impacts of Iodinated Contrast Media Agents (ICMs). We analyze an extensive collection of ICMs. A modeling approach resting on molecular docking and Density Functional Theory simulations is employed to examine the adsorption process at the molecular level. The study also relies on a Quantitative Structure-Activity Relationship (QSAR) modeling framework to correlate molecular properties with the adsorption energy (Ead) of ICMs, thus enabling identification of the key mechanisms underpinning adsorption and of the key factors contributing to it. A collection of distinct QSAR-based models is developed upon relying on Multiple Linear Regression and a standard genetic algorithm method. Having at our disposal multiple models enables us to take into account the uncertainty associated with model formulation. Maximum Likelihood and formal model identification/discrimination criteria (such as Bayesian and/or information theoretic criteria) are then employed to complement the traditional QSAR modeling phase. This has the advantage of (a) providing a rigorous ranking of the alternative models included in the selected set and (b) quantifying the relative degree of likelihood of each of these models through a weight or posterior probability. The resulting workflow of analysis enables one to seamlessly embed DFT and QSAR studies within a theoretical framework of analysis that explicitly takes into account model and parameter uncertainty. Our results suggest that graphene-based surfaces constitute a promising adsorbent for ICMs removal, π-π stacking being the primary mechanism behind ICM adsorption. Furthermore, our findings offer valuable insights into the potential of graphene-based adsorbent materials for effectively removing ICMs from water systems. They contribute to ascertain the significance of various factors (such as, e.g., the distribution of atomic van der Waals volumes, overall molecular complexity, the presence and arrangement of Iodine atoms, and the presence of polar functional groups) on the adsorption process.

An adult and pediatric size-based contrast administration reduction phantom study for single and dual-energy CT through preservation of contrast-to-noise ratio.

BACKGROUND: Global shortages of iodinated contrast media (ICM) during COVID-19 pandemic forced the imaging community to use ICM more strategically in CT exams. PURPOSE: The purpose of this work is to provide a quantitative framework for preserving iodine CNR while reducing ICM dosage by either lowering kV in single-energy CT (SECT) or using lower energy virtual monochromatic images (VMI) from dual-energy CT (DECT) in a phantom study. MATERIALS AND METHODS: In SECT study, phantoms with effective diameters of 9.7, 15.9, 21.1, and 28.5 cm were scanned on SECT scanners of two different manufacturers at a range of tube voltages. Statistical based iterative reconstruction and deep learning reconstruction were used. In DECT study, phantoms with effective diameters of 20, 29.5, 34.6, and 39.7 cm were scanned on DECT scanners from three different manufacturers. VMIs were created from 40 to 140 keV. ICM reduction by lowering kV levels for SECT or switching from SECT to DECT was calculated based on the linear relationship between iodine CNR and its concentration under different scanning conditions. RESULTS: On SECT scanner A, while matching CNR at 120 kV, ICM reductions of 21%, 58%, and 72% were achieved at 100, 80, and 70 kV, respectively. On SECT scanner B, 27% and 80% ICM reduction was obtained at 80 and 100 kV. On the Fast-kV switch DECT, with CNR matched at 120 kV, ICM reductions were 35%, 30%, 23%, and 15% with VMIs at 40, 50, 60, and 68 keV, respectively. On the dual-source DECT, ICM reductions were 52%, 48%, 42%, 33%, and 22% with VMIs at 40, 50, 60, 70, and 80 keV. On the dual-layer DECT, ICM reductions were 74%, 62%, 45%, and 22% with VMIs at 40, 50, 60, and 70 keV. CONCLUSIONS: Our work provided a quantitative baseline for other institutions to further optimize their scanning protocols to reduce the use of ICM.

The Effect of Mixing Iodinated Contrast Media and Ultrasound Contrast Agents on Subharmonic Signals.

Subharmonic aided pressure estimation (SHAPE) is a technique that utilizes subharmonic signals from microbubble contrast agents for pressure estimation. Validation of the SHAPE technique relies on synchronous measurements of in vivo pressures using contrast microbubbles and a pressure catheter (reference standard). For the guidance and placement of pressure catheter in vivo, iodinated contrast is used with fluoroscopy. Therefore, during data acquisition for validation studies of the SHAPE technique, both contrast microbubbles and iodinated contrast are present simultaneously within the vasculature. This study aims to elucidate the effects of iodinated contrast (Visipaque, GE HealthCare) on subharmonic signal amplitude from contrast microbubbles (Definity, Lantheus Medical Imaging, Inc.). In an acrylic water tank, 0.06 mL of Definity and varied amounts of Visipaque (0.14, 0.43, 0.85, and 1.70 mL) were added to 425 mL of deionized water. Ultrasound scanning was performed with a SonixTablet scanner (BK Medical Systems) using optimized parameters for SHAPE with Definity (ftransmit/receive = 3.0/1.5 MHz; chirp down pulse). Subharmonic data was acquired and analyzed at 9 different incident acoustic outputs (n = 3). Results showed an increase in subharmonic signal amplitude from Definity microbubbles in the presence of 0.14 mL Visipaque by 2.8 ± 1.3 dB (p < .001), no change with 0.85 mL Visipaque (0.7 ± 1.2 dB; p = .09) and a decrease in subharmonic amplitude in the presence of 1.70 mL Visipaque by 1.9 ± 0.7 dB (p < .001). While statistically significant effect on subharmonic signal amplitude of Definity microbubbles was noted due to the mixture, the magnitude of the effect was minimal (~2.8 dB) and unlikely to impact in vivo SHAPE measurements.

Adverse reactions after intravascular iodinated contrast media administration and their management.

Endovascular interventions and diagnostic examinations using iodinated contrast media (ICM) are standard of care in current vascular medicine. Although ICM use is generally considered safe, it may be associated with adverse reactions, vary from minor disturbances to rare, but severe life-threatening complications. This position paper of European Society of Vascular Medicine integrates current knowledge and summarizes the key information related to the use of intravascular ICM, serving as recommendation on prevention and management of acute, late, and very late adverse reactions. It should help the health professionals in all fields of vascular medicine to make decisions in daily practice for safe use of contrast media.

Occurrence of iodinated contrast media (ICM) in water environments and their control strategies with a particular focus on iodinated by-products formation: A comprehensive review.

Iodinated contrast media (ICM), one of the pharmaceutical and personal care products (PPCPs), are frequently detected in various water bodies due to the strong biochemical stability and recalcitrance to conventional water treatment. Additionally, ICM pose a risk of forming iodinated by-products that can be detrimental to the aquatic ecosystem. Consequently, effectively removing ICM from aqueous environments is a significant concern for environmental researchers. This article provides a comprehensive review of the structural characteristics of ICM, their primary source (e.g., domestic and hospital wastewater), detected concentrations in water environments, and ecological health hazards associated with them. The current wastewater treatment technologies for ICM control are also reviewed in detail with the aim of providing a reference for future research. Prior researches have demonstrated that traditional treatment processes (such as physical adsorption, biochemical method and chemical oxidation method) have inadequate efficiencies in the removal of ICM. Currently, the application of advanced oxidation processes to remove ICM has become extensive, but there are some issues like poor deiodination efficiency and the risk of forming toxic intermediates or iodinated by-products. Conversely, reduction technologies have a high deiodination rate, enabling the targeted removal of ICM. But the subsequent treatment issues related to iodine (such as I- and OI-) are often underestimated, potentially generating iodinated by-products during the subsequent treatment processes. Hence, we proposed using combined reduction-oxidation technologies to remove ICM and achieved synchronous control of iodinated by-products. In the future, it is recommended to study the degradation efficiency of ICM and the control efficiency of iodinated by-products by combining different reduction and oxidation processes.

MRA as the Preferred Test for Pulmonary Embolism During the Iodinated Contrast Media Shortage of 2022: A Single-Center Experience.

BACKGROUND. Closure of a GE Healthcare facility in Shanghai, China, in 2022 disrupted the iodinated contrast media supply. Technologic advances have addressed limitations associated with the use of pulmonary MRA for diagnosis of pulmonary embolism (PE). OBJECTIVE. The purpose of this study was to describe a single institution's experience in the use of pulmonary MRA as an alternative to CTA for the diagnosis of PE in the general population during the iodinated contrast media shortage in 2022. METHODS. This retrospective single-center study included all CTA and MRA examinations performed to exclude PE from April 1 through July 31 (18 weekly periods) in 2019 (before the COVID-19 pandemic and contrast media shortage), 2021 (during the pandemic but before the shortage), and 2022 (during both the pandemic and the shortage). From early May through mid-July of 2022, MRA served as the preferred test for PE diagnosis, to preserve iodinated contrast media. CTA and MRA reports were reviewed. The total savings in iodinated contrast media volume resulting from preferred use of MRA was estimated. RESULTS. The study included 4491 examinations of 4006 patients (mean age, 57 ± 18 [SD] years; 1715 men, 2291 women): 1245 examinations (1111 CTA, 134 MRA) in 2019, 1547 examinations (1403 CTA, 144 MRA) in 2021, and 1699 examinations (1282 CTA, 417 MRA) in 2022. In 2022, the number of MRA examinations was four (nine when normalized to a 7-day period) in week 1, and this number increased to a maximum of 63 in week 10 and then decreased to 10 in week 18. During weeks 8-11, more MRA examinations (range, 45-63 examinations) than CTA examinations (range, 27-46 examinations) were performed. In 2022, seven patients with negative MRA underwent subsequent CTA within 2 weeks; CTA was negative in all cases. In 2022, 13.9% of CTA examinations (vs 10.3% of MRA examinations) were reported as having limited image quality. The estimated 4-month savings resulting from preferred use of MRA in 2022, under the assumption of uniform simple linear growth in CTA utilization annually and a CTA dose of 1 mL/kg, was 27 L of iohexol (350 mg I/mL). CONCLUSION. Preferred use of pulmonary MRA for PE diagnosis in the general population helped to conserve iodinated contrast media during the 2022 shortage. CLINICAL IMPACT. This single-center experience shows pulmonary MRA to be a practical substitute for pulmonary CTA in emergency settings.

Institutional response to the 2022 iodinated contrast shortage: A narrative review.

INTRODUCTION: The iodinated contrast material (ICM) shortage of 2022 has affected healthcare systems worldwide, forcing institutions to adapt by implementing interventions to conserve ICM without compromising patient care. We aim to present the practices proven to be effective in reducing ICM consumption to improve resource allocation in trauma patients. METHODS: A literature search of PubMed, Google Scholar, and Cochrane was conducted. Studies investigating the utility of ICM in the management of trauma & emergency surgery patients, as well as institutional interventions that were implicated as a response to the ICM shortage of 2022 were included for review. RESULTS: Eight articles were selected and reviewed. The use of alternative, non-contrast-enhanced imaging modalities, particularly non-contrast-enhanced CT (NECT), was found to be effective in reducing ICM consumption. Other institutions have implemented strategies to reduce the ICM dose for each imaging study performed, including decreasing ICM dose itself as well as reducing tube voltage, which was shown to reduce ICM use by 50%. Waste minimization by splitting single-dose contrast vials into smaller aliquots utilized for multiple imaging studies has also been an effective method. Additionally, assembling a Radiology Command Center Team, responsible for monitoring ICM supplies while offering 24/7 consults regarding options for alternative imaging, has resulted in an overall reduction in contrast consumption of 50% in 7 days. CONCLUSION: In response to the ICM shortage of 2022, most healthcare institutions have found the use of alternative imaging modalities to be effective in reducing ICM consumption. Other effective measures include ICM dose reduction and ICM waste minimization.

Late adverse events to iodinated contrast media in patients treated with IL-2: a safety report from the Danish Renal Carcinoma Group (DaRenCa) study - 1.

BACKGROUND: A higher incidence of late adverse events (LAEs) to iodinated contrast media in interleukin-2 (IL-2)-treated patients has been reported. PURPOSE: To assess the incidence of LAEs after administration of iodinated contrast media in patients with metastatic renal cell carcinoma (mRCC) treated with IL-2. MATERIAL AND METHODS: Patients were randomized to treatment with IL-2 and interferon-α with/without bevacizumab in the Danish Renal Carcinoma Group study - 1. Patients underwent a computed tomography (CT) scan at baseline, at one month, at three months, and every third month until RECIST 1.1 defined progression. LAEs due to iodinated contrast media were systematically registered according to the Common Terminology Criteria for Adverse Events classification. RESULTS: In total, 89 patients were included and underwent a total of 507 contrast-enhanced CT scans. An overall incidence of 46 (9.1%) LAEs was observed in 38 of 89 (42.7%) patients; 3 LAEs at baseline (3.4% of all baseline scans), 39 (13.9%) LAEs during IL-2-based therapies, and 4 (2.9%) LAEs after termination of IL-based therapies. There was no difference in progression-free survival, overall survival, and treatment response in patients experiencing LAEs compared to patients without LAEs (P = 0.2, P = 0.5, and P = 0.6, respectively). CONCLUSION: Patients with mRCC demonstrated a higher incidence of LAEs after administration of iodinated contrast during ongoing IL-2 therapy, indicating that iodinated contrast media may cause a recall phenomenon of IL-2 toxicities in patients with mRCC. Treatment with IL-2 should not be a contraindication for contrast-enhanced scans in patients with mRCC but expertise and vigilance are required.

Impact of iodinated contrast media concentration on image quality for dual-energy CT and single-energy CT with low tube voltage settings.

BACKGROUND: Contrast-induced nephropathy (CIN) is an adverse reaction associated with the use of intravenous contrast media (CM). PURPOSE: To investigate the impact of low tube voltage settings on single-energy computed tomography (SECT) and rapid kV switching dual-energy CT (DECT) with reduced concentrations of iodinated CM. MATERIAL AND METHODS: A phantom containing four different concentrations of CM (original concentration CM, 20%, 40%, and 60% reductions) was scanned using SECT mode with varying tube voltages (70, 80, 100, and 120 kVp) and DECT mode through reconstructing monoenergetic energy (50 keV and 70 keV) images. ATCM system with different noise index (NI) settings were set, and the images were reconstructed using ASiR-V. Image quality were measured for individual phantom sizes and protocols and compared to a reference protocol for SECT of 120 kVp, NI = 18, threshold contrast enhancement ≥280 HU, and CNR ≥17. RESULTS: Tube voltage settings of 70 kVp together with 40% reduction in the iodinated CM is suitable for small phantom size, those of 80 kVp and 20% reduction is suitable for the medium and large sizes. This allows radiation doses to be reduced by 12%-30%. Values of CNR and contrast for DECT are better than those for SECT with the same NI setting. CONCLUSION: Diagnostic reference of image quality can be maintained by using SECT with lower tube voltage and DECT with reductions of iodinated CM concentration and radiation dose. Therefore, the NI setting can be increased when DECT is used to achieve a similar image quality.

Delayed hypersensitivity reactions to iodinated contrast media: A diagnostic approach by skin tests.

BACKGROUND: Adverse drug reactions to iodinated contrast media (ICM) have risen due to their increasing use in x-ray-based imaging modalities. Delayed hypersensitivity reactions are mainly caused by nonionic monomeric compounds and represent an issue impacting the diagnostic-therapeutic pathways of cancer, cardiology and surgery patients. OBJECTIVES: To prospectively evaluate the usefulness of skin tests in delayed hypersensitivity reactions to ICM and to evaluate the tolerability of iobitridol, a monomeric nonionic low osmolality compound, as a possible safe alternative. METHODS: Patients with delayed hypersensitivity reactions to ICM referred to us from 2020 to 2022 were prospectively enrolled in the study. All patients underwent patch test and, if negative, intradermal test with the culprit ICM and iobitridol as alternative. RESULTS: A total of 37 patients (females 24, 64.9%) were enrolled in the study. Iodixanol and iomeprol were the most frequently involved ICM (48.5% and 35.2%, respectively); 62.2% of patients presented maculopapular eruption, while 37.8% reported delayed urticaria-like rash. Skin tests resulted positive to the culprit ICM in 19 patients (51.4%), 16 to patch test and 3 to intradermal test. Skin tests with iobitridol, tested as alternative, resulted positive in 3/19 patients (15.8%). All 16 patients with negative results to iobitridol were administered this ICM and tolerated it. CONCLUSIONS: In at least half of patients, delayed-type hypersensitivity was demonstrated by skin tests, particularly by patch test. This diagnostic approach resulted simple, cost-effective and safe, not only to confirm the culprit ICM but also to identify iobitridol as feasible alternative.

[How I explore an hypersensitivity to iodinated contrast media]. / Comment j'explore... une hypersensibilité aux produits de contraste iodés.

Immediate or delayed hypersensitivity reactions to iodinated contrast media (ICM) occur in 0.5-3 % of patients receiving radiological examinations using the last generation ICM. Although the majority of the reactions are mild to moderate, severe and potentially lethal reactions may occasionally be observed. In the last few years, there has been an increase of patients referred to the dermato-allergology department for the work-up of a hypersensitivity reaction to ICM. In this article, the allergological investigations and their indications are described in the case of a suspicion of ICM hypersensitivity.

Les réactions d'hypersensibilités immédiates ou retardées aux produits de contraste iodés (PCI) surviennent chez 0,5-3 % des patients bénéficiant d'un examen d'imagerie radiologique utilisant les PCI de dernière génération. Bien que la plupart des réactions soient d'intensité faible à modérée, des réactions sévères, parfois mortelles, sont possibles. Depuis quelques années, on note une nette augmentation du nombre de patients adressés en consultation de dermato-allergologie pour mise au point de réaction d'hypersensibilité aux PCI. Dans cet article, l'exploration allergologique devant une suspicion d'hypersensibilité aux PCI est décrite avec ses indications.

Research progress on desensitization of hypersensitivity reaction to iodinated contrast media. / ç¢˜é€ å½±å‰‚è¶ æ•ååº”æ‚£è€ è„±æ•æ²»ç–—çš„ç ”ç©¶è¿›å±•.

Desensitization therapy for iodinated contrast media (ICM) aims to induce drug tolerance in patients with a history of severe allergic reactions to ICM in a short time. Currently, there is no widely accepted consensus on inducing desensitization to avoid severe allergic responses to ICM. The clinically successful cases have shown that prophylactic use of antihistamines and glucocorticoids can increase the desensitization effect; repeatedly desensitizing and gradually increasing the dose can be conducive to establishing better tolerance to ICM. Most desensitization effects, including stress resistance, can endure 24-48 h. The mechanisms of desensitization therapy remain unclear, the initial dose, administration interval and dose gradient are largely based on clinical experiences and the reaction of patients. This article reviews the current research progress on ICM-related allergies, desensitization methods and related mechanisms, as well as the benefits and hazards of desensitization, to provide a reference for desensitization treatment of hypersensitivity to ICM .

Association between acute adverse reactions to iodinated contrast media and anxiety in patients undergoing contrast-enhanced CT examination. / CTå¢žå¼ºæ£€æŸ¥ä¸­ç¢˜å¯¹æ¯”å‰‚æ€¥æ€§ä¸è‰¯ååº”ä¸Žç„¦è™‘çŠ¶æ€çš„ç›¸å ³æ€§.

OBJECTIVES: As the use of iodinated contrast media has become more widely with advances in imaging, several guidelines have suggested that anxiety increases the risk of acute adverse reactions associated with iodinated contrast media. This study aims to evaluate the impact of anxiety on the occurrence of acute adverse reactions (AAR) to iodinated contrast media in patients undergoing contrast-enhanced CT examinations. METHODS: Inpatients who underwent contrast-enhanced CT examinations at the Third Xiangya Hospital between February and October 2021 were prospectively recruited. Prior to the imaging examinations, all patients completed the Generalized Anxiety Disorder Scale-7 (GAD-7) assessment before the imaging examinations to determine the severity of anxiety, which was categorized as mild, moderate, or severe. Based on the occurrence of AAR, patients were classified into an AAR group and a non-AAR group. The difference in anxiety was compared between the 2 groups. Multivariate logistic regression analysis was used to identify independent risk factors associated with AAR. To ensure comparability between the 2 groups, propensity score matching (PSM) was utilized to align the clinical characteristics. Subsequently, the difference in anxiety within the matched groups was analyzed. RESULTS: The study comprised 880 patients, with 80 patients in the AAR group and 800 patients in the non-AAR group. There was a significant difference in proportion of patients with mild-severe anxiety between the 2 groups (75% in the AAR group and 36% in the non-AAR group, P<0.001). Additionally, differences were also observed in occupation, income, underlying diseases, and allergy history (all P<0.001). The results of multivariate logistic regression analysis revealed that patients' income, allergy history, and anxiety were independent risk factors for AAR to iodinated contrast media (all P<0.05). Following PSM, each matched group included 66 cases, and no significant differences in clinical characteristics were observed between the 2 groups (all P>0.05). However, the proportion of patients with mild-severe anxiety remained significantly higher in the AAR group compared to the non-AAR group (75% in the AAR group and 31% in the non-AAR group, P<0.001). CONCLUSIONS: Anxiety is associated with an increased risk of AAR to iodinated contrast media in patients undergoing contrast-enhanced CT examinations, suggesting the clinical importance of screening for anxiety before imaging examinations.

Non-immediate hypersensitivity reactions to iomeprol: Diagnostic value of skin tests and cross-reactivity with other iodinated contrast media.

BACKGROUND: Iodinated contrast media produce non-immediate hypersensitivity reactions (NIHR). The goal of this prospective study was to determine the utility of skin tests and the subsequent tolerance to negative skin-tested iodinated contrasts in patients with NIHR caused by iomeprol. METHODS: Prick and intradermal tests with iomeprol, iopamidol, iopromide, and iobitridol were performed in all patients. IV challenge with the causative contrast (iomeprol in 90%) was made if skin tests were negative. In case of a positive skin test with the causal contrast, or a positive challenge test with it, IV challenge test with an alternative, negative skin-tested contrast was performed in all patients. RESULTS: Skin tests were positive in 47.6% (20/42) of patients with NIHR induced by iomeprol. Of the 66 challenge tests performed with negative skin-tested iodinated contrasts, tolerance was confirmed in 35 (53%): 32 iomeron, 2 iobitridol, 1 iopamidol. Cross-reactivity between iomeprol and iopamidol was 22% (4/20 in patients with positive skin tests and 5/21 in patients with negative skin tests). CONCLUSIONS: Sensitivity of the skin tests was less than 50% NIHRs due to iomeprol, while the negative predictive value of skin tests in patients who tolerated challenges with alternative contrasts (mainly iopamidol) was 53% (35 tolerated out of 66 performed). The cross-reactivity between iomeprol and iopamidol is high.

Utility of Patient-Reported Risk Factors for Identifying Advanced Chronic Kidney Disease Before Outpatient CT: Comparison With Recent ACR/NKF Consensus Criteria.

BACKGROUND. Practices vary for screening patients for risk of renal dysfunction before administration of iodinated contrast medium. A 2020 American College of Radiology/National Kidney Foundation (ACR/NKF) consensus statement provided streamlined screening criteria. OBJECTIVE. The purpose of this study was to assess the yield of patient-reported risk factors for identifying estimated glomerular filtration rate (eGFR) less than 30 mL/min/1.73 m2 before outpatient CT. METHODS. This retrospective study was performed at a health system that implemented an electronic screening form for patients to complete before outpatient CT encounters to report undergoing dialysis, taking cancer-treating medications, having kidney disease, undergoing prior kidney surgery, having diabetes mellitus treated with medication, having hypertension treated with medication, or having multiple myeloma. Patients with any risk factor were required to undergo eGFR testing before CT. Of 44,708 patients completing the form from June 1, 2020, through February 28, 2021, 10,256 patients (5315 men, 4941 women; mean age, 66.8 ± 11.9 [SD] years; range, 21-98 years) underwent eGFR testing on the day of CT. Multivariable regression analysis for predicting reduced eGFR was performed. Findings were compared with those from theoretic use of the ACR/NKF criteria. RESULTS. Same-day testing yielded eGFR less than 30 mL/min/1.73 m2 in 1.4% (144/10,256) of patients. The only significant independent predictors of low eGFR were dialysis (odds ratio [OR], 203.30], kidney disease (OR, 12.55), and diabetes mellitus treated with medication (OR, 2.44). If the ACR/NKF criteria (only kidney disease, defined as dialysis, kidney disease, or prior kidney surgery) had been followed as a trigger for eGFR testing, the number of patients needing testing would have decreased 89.7%, from 10,256 to 1059; yield would have increased to 7.2% (76/1059); and 47.2% (68/144) of patients with low eGFR would have been missed. If the ACR/NKF criteria had been followed but diabetes mellitus been considered a required rather than an optional criterion, the number of patients needing testing would have decreased 77.1%, to 2353; yield would have increased to 4.0% (95/2353); and 34.0% (49/144) of patients with low eGFR would have been missed. CONCLUSION. Using patient-reported risk factors resulted in frequent eGFR testing but low yield of low eGFR. Commonly applied risk factors were not independently associated with low eGFR. CLINICAL IMPACT. Application of ACR/NKF criteria would substantially reduce eGFR testing, but patients with renal dysfunction would be missed. The statement should consider omitting kidney surgery as a trigger for eGFR testing and including diabetes mellitus as a required trigger.

Oral hydration as a safe prophylactic measure to prevent post-contrast acute kidney injury in oncologic patients with chronic kidney disease (IIIb) referred for contrast-enhanced computed tomography: subanalysis of the oncological group of the NICIR study.

BACKGROUND: T he objective of this study is to evaluate oral hydration compared to intravenous (i.v.) hydration in the prevention of post-contrast acute kidney injury (PC-AKI) in the oncologic subgroup of patients with stage IIIb chronic kidney disease (CKD) included in the NICIR study referred for elective contrast-enhanced computed tomography (CE-CT). MATERIAL AND METHODS: We performed a retrospective subanalysis of the oncological subgroup (174/228 patients, 74%) from a continuous prospective database of patients included in the recently published non-inferiority NICIR study. Patients received prophylaxis against PC-AKI with either oral hydration (500 mL of water 2 h before and 2000 mL during the 24 h after CE-CT) or i.v. hydration (sodium bicarbonate (166 mmol/L) 3 mL/kg/h starting 1 h before and 1 mL/kg/h during the first hour after CE-CT). The primary outcome was to compare the proportion of PC-AKI in the first 48 to 72 h after CE-CT in the two hydration groups. Secondary outcomes were to compare persistent PC-AKI, the need for haemodialysis, and the occurrence of adverse events related to prophylaxis in each group. RESULTS: Of 174 patients included in the subanalysis, 82 received oral hydration and 92 received i.v. hydration. There were no significant differences in clinical characteristics or risk factors between the two study arms. Overall the PC-AKI rate was 4.6% (8/174 patients), being 3.7% in the oral hydration arm (3/82 patients) and 5.4% (5/92 patients) in the i.v. hydration arm. The persistent PC-AKI rate was 1.2% (1/82 patients) in the oral hydration arm and 3.3% (3/92 patients) in the i.v. hydration arm. No patient required dialysis during the first month after CE-CT or had adverse effects related to the hydration regime. CONCLUSION: In oncological patients with stage IIIb CKD referred for elective CE-CT, the rate of PC-AKI in those receiving oral hydration did not significantly differ from that of patients receiving i.v. hydration.