Iodinated Contrast Media Substitution to Prevent Recurrent Hypersensitivity Reactions: A Systematic Review and Meta-Analysis.

Background Changing iodinated contrast media (ICM) may reduce the risk of recurrent ICM-induced hypersensitivity reactions in patients with a prior reaction. Purpose To perform a systematic review on the effectiveness of ICM change in comparison with no change to prevent recurrent ICM immediate hypersensitivity reactions. Materials and methods Multiple data bases were searched without language restriction between January 1990 and August 2021 to identify comparative studies of any design that included patients with a prior ICM hypersensitivity reaction to low-osmolality ICM and re-exposure to intravascular ICM. The methods used included a duplicate assessment of eligibility, double extraction of quantitative data, validity assessment, and random-effects meta-analysis. The primary outcome was the incidence of all-grade immediate recurrent hypersensitivity reactions. Secondary outcomes were the incidence of severe immediate recurrent hypersensitivity reactions and other adverse events associated with ICM change. Results Six retrospective observational studies at moderate to severe risk of bias assessed 7155 adult patients (4329 in the ICM change group and 2826 in the no-change group). Studies adopted nonstandardized switching methods, and the proportions of the ICM change group ranged between 19% (five of 27 examinations) and 80% (3104 of 3880 examinations). A Bayesian meta-analysis revealed that changing ICM was associated with a reduced risk of recurrent hypersensitivity reaction by 61% (risk ratio = 0.39; 95% credible interval [CrI]: 0.24, 0.58). The wide-ranging estimates of risk reduction were not explained by the risk of bias ratings, the event rates in the no-change group, the index-reaction severity, or the co-administered nonstandard premedication. Rare severe recurrent reactions (five studies with five events) precluded a conclusion (risk ratio = 0.34, favoring ICM change; CrI: 0.01, 3.74). Adverse events associated with ICM change were not reported. Conclusion In observational evidence of limited quality, iodinated contrast media (ICM)-change was associated with a reduced risk of recurrent immediate hypersensitivity reaction in patients with a prior ICM-induced hypersensitivity reaction. © RSNA, 2022 Online supplemental material is available for this article. See also the editorial by McDonald in this issue.

Relationship between Lower Dose and Injection Speed of Iodinated Contrast Material for CT and Acute Hypersensitivity Reactions: An Observational Study.

BackgroundThere are few data on the relationship between acute hypersensitivity reactions and the dose and injection rate of iodinated contrast material for CT.PurposeTo determine the relationship between lower dose and injection speed of iodinated contrast material for CT and the rate of acute hypersensitivity reactions.Materials and MethodsThis retrospective study included adults (age ≥18 years) undergoing nonionic iodinated contrast material-enhanced abdominal CT between August 2016 and January 2017 (control period) and between August 2017 and January 2018 (intervention period); all examinations were conducted in an outpatient setting. Compared with CT during the control period, CT during the intervention period involved a reduced dose of contrast material achieved by lowering the CT tube voltage. CT examinations in the control period were performed with 120 kVp, a contrast material dose of 2 mL/kg (maximum, 150 mL), and an injection speed of 3 or 4 mL/sec. CT examinations in the intervention period were performed with 100 kVp, a contrast material dose of 1.5 mL/kg (maximum, 130 mL), and an injection speed of 2.5 or 3 mL/sec. Per-examination rates of acute hypersensitivity reactions to iodinated contrast material were compared between the control and intervention periods with use of a multivariable Poisson regression model, the parameters of which were estimated by using generalized estimating equations with an independence correlation structure.ResultsA total of 21947 adults (mean age ± standard deviation, 59 years ± 12; 8797 women [40%]) underwent 25119 CT examinations during the control period; 23019 adults (mean age, 59 years ± 12; 9538 women [41%]) underwent 26491 CT examinations during the intervention period. The rate of acute hypersensitivity reactions was 1.42% (376 of 26491 examinations; 95% confidence interval [CI]: 1.28%, 1.57%) in the intervention period and 1.86% (468 of 25119 examinations; 95% CI: 1.70%, 2.04%) in the control period, with a multivariable-adjusted relative risk of 0.85 (95% CI: 0.74, 0.99; P = .03).ConclusionReduction in the dose and injection speed of iodinated contrast material for CT was associated with a lower rate of acute hypersensitivity reactions to iodinated contrast material.© RSNA, 2019Online supplemental material is available for this article.

Hypersensitivity Reactions to Iodinated Contrast Media: A Multicenter Study of 196 081 Patients.

Background Multicenter studies may be required for establishing guidelines for safe usage of iodinated contrast media (ICM). Purpose To identify the prevalence, patterns, risk factors, and preventive measures for ICM-related hypersensitivity reactions (HSRs). Materials and Methods Between March 2017 and October 2017, a total of 196 081 patients who underwent ICM administration were enrolled from seven participating institutions. The occurrence of HSRs and baseline patient information were recorded. χ2 and Student t test were performed, and logistic regression analyses were used to identify risk factors that predict occurrence and recurrence of HSR. Results Among 196 081 patients (mean age ± standard deviation, 59.1 years ± 16.0; 105 014 men and 91 067 women) who underwent ICM administration, the overall prevalence of HSRs was 0.73% (1433 of 196 081), and severe reactions occurred in 0.01% (17 of 196 081). Conditional logistic regression for patients with HSR (n = 1433) and a control group (1:1 matched group for age, sex, ICM product, and institution) demonstrated that a patient's previous individual history of an ICM-related HSR (adjusted odds ratio [OR], 198.8; P < .001), hyperthyroidism (adjusted OR, 3.6; P = .04), drug allergy (adjusted OR, 3.5; P < .001), and other allergic diseases (adjusted OR, 6.8; P < .001) and a family history of ICM-related HSRs (adjusted OR, 14.0; P = .01) were predictors of HSR occurrence. Logistic regression analysis showed that use of premedication with antihistamine (OR, 0.5; P = .01) and change in the generic profile of ICM (OR, 0.5; P < .001) were preventive against recurrent HSR. Conclusion Family history as well as previous individual history of hypersensitivity reactions (HSRs) to iodinated contrast media (ICM) were risk factors for HSR occurrence, suggesting a potential genetic predisposition. A change in the culprit ICM and premedication with antihistamine are useful for reducing the recurrence of HSRs. © RSNA, 2019 Online supplemental material is available for this article.

Iodinated Contrast Agents and Risk of Hypothyroidism in Young Children in the United States.

BACKGROUND: Although it is generally acknowledged that exposure to iodine contrast agents can interfere with thyroid function, little is known about the incidence of iodine-induced hypothyroidism in young children (younger than the age of 4 years). STUDY OBJECTIVES: This was a retrospective cohort study to estimate the incidence rate of detected hypothyroidism in a US-based general population of pediatric patients exposed to an iodinated contrast agent. SETTING: The study was conducted in Kaiser Permanente Northern California, an integrated health care delivery system. STUDY POPULATION: This study included 2320 pediatric patients younger than 4 years of age who had a diagnostic procedure with an iodinated contrast agent during years 2008 to 2016. RESULTS: Among 2320 young children who met our study criteria, we identified 34 who met the initial criteria to be a case of hypothyroidism. The incidence density ratio for all hypothyroidism in iodine contrast agent-exposed patients was 1.33 per 1000 person months (95% confidence interval, 0.9-1.8). Most cases appeared to have subclinical hypothyroidism. The rate was higher for the probably iodine-induced cases (0.90 per 1000 person months) compared with cases with a possible alternate etiology (0.43 per 1000 person months), for males compared with females, and among children who had a heart catheterization compared with those with a computed tomography scan. It was also highest among the youngest children (younger than 3 months old), and decreased with increasing age. DISCUSSION: Our finding of hypothyroidism in young children exposed to iodine contrast agents (1.33 per 1000 person months [95% confidence interval, 0.9-1.8]) is broadly consistent with the sparse literature on this outcome.

Types of antiseptics, presentations and rules of use. / Tipos de antisépticos, presentaciones y normas de uso.

Antiseptics are chemical substances that when applied topically onto intact skin, mucous membranes or wounds partially or completely reduces the population of living microorganisms in those tissues. Different types of antiseptics are available - those most commonly used in clinical practice being alcohols, iodinated compounds and chlorhexidine. When using an antiseptic, consideration is required of its spectrum of antimicrobial activity, latency, residual effects, possible interferences of the presence of organic material with the activity of the antiseptic, its side effects, compatibility with other antiseptics, and cost. This article is part of a supplement entitled "Antisepsis in the critical patient", which is sponsored by Becton Dickinson.

Iodine supplementation during pregnancy and lactation. Position statement of the working group on disorders related to iodine deficiency and thyroid dysfunction of the Spanish Society of Endocrinology and Nutrition.

Severe and mild iodine deficiency during pregnancy and lactation affects thyroid function of the mother and neonate as well as the infant's neuropsychological development. Studies performed in Spain confirm that most women are iodine deficient during pregnancy and lactation. Pregnant and breast feeding women and women planning to become pregnant should take iodine supplements.

Contrast-induced kidney injury: mechanisms, risk factors, and prevention.

In general, iodinated contrast media (CM) are tolerated well, and CM use is steadily increasing. Acute kidney injury is the leading life-threatening side effect of CM. Here, we highlight endpoints used to assess CM-induced acute kidney injury (CIAKI), CM types, risk factors, and CIAKI prevention. Moreover, we put forward a unifying theory as to how CIAKI comes about; the kidney medulla's unique hyperosmolar environment concentrates CM in the tubules and vasculature. Highly concentrated CM in the tubules and vessels increases fluid viscosity. Thus, flow through medullary tubules and vessels decreases. Reducing the flow rate will increase the contact time of cytotoxic CM with the tubular epithelial cells and vascular endothelium, and thereby damage cells and generate oxygen radicals. As a result, medullary vasoconstriction takes place, causing hypoxia. Moreover, the glomerular filtration rate declines due to congestion of highly viscous tubular fluid. Effective prevention aims at reducing the medullary concentration of CM, thereby diminishing fluid viscosity. This is achieved by generous hydration using isotonic electrolyte solutions. Even forced diuresis may prove efficient if accompanied by adequate volume supplementation. Limiting the CM dose is the most effective measure to diminish fluid viscosity and to reduce cytotoxic effects.

Iodine excess.

Several mechanisms are involved in the maintenance of normal thyroid hormone secretion, even when iodine intake exceeds physiologic needs by a factor of 100. The sodium-iodide symporter system contributes most to this stability. Faced with an iodine excess, it throttles the transport of iodide into the thyroid cells, the rate-limiting step of hormone synthesis. Even before the iodine symporter reacts, a sudden iodine overload paradoxically blocks the second step of hormone synthesis, the organification of iodide. This so-called Wolff-Chaikoff effect requires a high (>or=10(-3) molar) intracellular concentration of iodide. The block does not last long, because after a while the sodium-iodide symporter shuts down; this allows intracellular iodide to drop below 10(-3) molar and the near-normal secretion to resume. In some susceptible individuals (e.g., after radio-iodine treatment of Graves' disease or in autoimmune thyroiditis), the sodium-iodide symporter fails to shut down, the intracellular concentration of iodide remains high and chronic hypothyroidism ensues. To complicate matters, iodine excess may also cause hyperthyroidism. The current explanation is that this happens in persons with goitres, for example, after long-standing iodine deficiency. These goitres may contain nodules carrying a somatic mutation that confers a 'constitutive' activation of the TSH receptor. Being no more under pituitary control, these nodules overproduce thyroid hormone and cause iodine-induced hyperthyroidism, when they are presented with sufficient iodine. These autonomous nodules gradually disappear from the population after iodine deficiency has been properly corrected. More recent studies suggest that chronic high iodine intake furthers classical thyroid autoimmunity (hypothyroidism and thyroiditis) and that iodine-induced hyperthyroidism may also have an autoimmune pathogenesis.

[Is dialysis efficient in the prevention of ionic contrast agent-induced nephropathy?]. / Néphropathie induite par les produits de contraste iodés, l'epuration extrarénale est-elle efficace en prévention?

UNLABELLED: A FREQUENT AND EXPENSIVE PROBLEM: Ninety percent of contrast media nephrotoxicity (CMN) occur in patients with pre-existing kidney failure. Its aggravation may require early chronic dialysis. PREVENTIVE MEASURES: CMN prophylaxis is important in these patients. Pre- and post-hydration, with infusion of isotonic saline solution or sodium bicarbonate, and reduction of contrast medium (CM) volume to the strict minimum are essential for preventing CM-induced kidney failure. THE INTEREST OF PROPHYLACTIC HEMODIALYSIS AND HEMOFILTRATION: An interesting approach in preventing CMN is the early elimination of the CM with dialysis techniques. Preventive hemodialysis does not reduce the risk of CMN, but hemofiltration has shown significant efficacy in a population of patients with kidney failure. THE INTEREST OF IMMEDIATE HEMODIALYSIS IN CHRONIC HEMODIALYSIS PATIENTS: Although nephrotoxicity is no longer a problem in patients undergoing chronic hemodialysis, CM, especially in high-dose injections, may be responsible for fluid and electrolyte abnormalities and/or volemic expansion. No data yet justify a conclusion that a hemodialysis session immediately after injection of a CM in chronic dialysis patients might be helpful.

Vasomotor effects of iodinated contrast media: just side effects?

Routinely used iodinated contrast media have complex vasomotor effects on several arterial districts. All classes of iodinated radiographic contrast media are vasoactive, with iso-osmolar dimers inducing the smallest changes in vascular tone. The mechanisms responsible for contrast-induced vasomotor changes are not fully elucidated and are likely to be multifactorial. Although contrast-induced vasomotility is usually considered as an unwanted "side effect", recent findings suggest that it might indeed be useful in exploring the functional integrity of the vessel wall. We found that atherosclerosis has an impact on the type of the contrast-induced coronary vasomotor reaction. In fact, angiographically normal coronary segments show divergent vasomotor reactions to iodixanol or iopromide according to the presence/absence of, and distance from, a coronary atherosclerotic lesion located in their proximity. The mechanism responsible for this vasomotor effect does not apparently involve flow-mediated vasodilatation or endothelial nitric oxide synthesis. On the other hand, a cyclooxygenase product may be, at least in part, responsible for the vasodilating effect of non-ionic agents on epicardial coronary arteries, since contrast-induced vasodilatation is strongly inhibited in the presence of indomethacin. These findings have potential clinical implications, since the analysis of contrast-induced coronary vasomotion might result in a new test capable of evaluating vascular functional integrity. Such a test might be alternative or complementary to the tests based on muscarinic agonists (acetylcholine) or serotonin, which are known to evaluate the nitric oxide pathway.

Time-course of iodine elimination by hemodialysis in patients with renal failure after angiography.

The study was designed to examine the time-course of iodine elimination by hemodialysis to determine a desirable duration for dialysis after angiography to prevent contrast media nephropathy (CMN) in patients with renal failure. Reduction rates of iodine by hemodialysis (DRR) of 1 to 3 h and the renal elimination of iodine (RER) for 20 h after hemodialysis were prospectively examined in 8 chronic renal failure (CRF) patients. The mean DRR was 46.6% at 1 h, 65.2% at 2 h, and 75.1% at 3 h, and the mean RER was 49.4% in the CRF patients. Renal function significantly deteriorated in 2 CRF patients after angiography. Plasma iodine was eliminated by more than 80% after 2 h of hemodialysis following angiography, and the subsequent renal elimination in patients with mild-to-moderate renal failure was also examined. There is no need of prophylactic hemodialysis to prevent CMN for these patients when they have no additional risk factors such as a high dose of contrast medium, diabetes mellitus, or severe heart failure. However, 2 h of hemodialysis is desirable immediately after angiography for patients with moderate renal failure and one additional risk factor, and three hours or more of hemodialysis is also desirable for patients with severe renal failure, and for those with moderate renal failure having two or more additional risk factors.

[Cor thyreotoxicum. Part I--new findings about its etiopathogenesis and diagnosis. Overview of problems based on 35 years' experience]. / Cor thyreotoxicum. Cast' I.--súcasné novosti v jeho etiopatogenéze a diagnostike. (Prehlad problematiky na základe 35-rocných skúseností).

In the seventies thyrotoxic heart accounted for 3% of all hospitalized cardiac patients and was found on average in 30% of all cases of hyperthyroidism. It presented most frequently by tachyfibrillation and resistant cardiac decompensation. It affected men four times as frequently as women. The incidence correlated with age, toxic nodose goitre, but its development did not correlate with concurrent thyrotoxic rhizomyelic myopathy nor with the extent of deviation of thyroid laboratory parameters (T4, T3, indexes FT4). At present the incidence of thyrotoxic heart declined due to early detection and more adequate diagnosis and treatment of hyperthyroidism, as well as due to the decline of oligosymptomatic toxic nodose goitres even in old age due to preventive iodization of table salt. However, there was an increase of hyperthyroidism induced by amiodarone and other iodine preparations (X-ray contrast materials) associated with primary heart disease and arrhythmias. (Up to 2% of amiodarone treated patients). The ratio of so-called real subclinical thyrotoxicoses in the development of thyrotoxic heart is negligible. Isolated reduction of TSH in hospital screening is a frequent finding but is conditioned most frequently by: a) the 1st stage of the low thyroxin syndrome, b) the 1st stage of subacute thyroiditis, c) the influence of various drugs (iodine preparations, overdosage of T4 substitution, pharmacotherapy with glucocorticoids, dopamine etc.), d) methodical artefacts, e) natural pulsed secretion of TSH etc. Hospital screening of hyperthyroidism and thyrotoxic heart even in older people above 60 years by T4 and/or TSH (2nd generation equipment) is not effective because it is detected in 20% of current hospital admissions and in 60% of those admitted to intensive care unitpathologic values of T4 and/or TSH most frequently without non-thyroid causes (stages of the low thyroxin syndrome) are recorded. This hospital screening has a satisfactory sensitivity but low specificity and in a large number of people calls for further diagnostic steps. Therefore it is more suitable only after clinical examination of the patient to confirm suspected hyperthyroidism to examine FT4 and TSH (IRMA 3rd generation) or possibly supplement FT3 and other aimed tests.

Reacciones adversas a los medios de contraste yodados en pacientes tratados con interleuquina 2 / Adverse effects to iodinated contrast media in irterleukin-2 treated patients

Objetivo: La interleuquina 2 (IL-2) es un potente estimulador de la respuesta inmune que provoca regresión tumoral en pacientes oncológicos. Sin embargo, como contrapartida, la IL-2 puede inducir sensibilización a los medios de contraste yodados (MCI), fenómeno descrito con poca frecuencia en la bibliografía. En este trabajo describimos el incremento de reacciones adversas a los MCI en nuestros pacientes tratados con IL-2 y planteamos actitudes de manejo específicas ante esta situación.Material y método: Se realizó un análisis retrospectivo de 712 pacientes oncológicos (168 tratados con IL-2 y un grupo control de 544 sin este tratamiento) estudiados mediante tomografía computarizada (TC) con contraste intravenoso (administración de 80-160 ml de MCI no iónico a través de un inyector). Ningún paciente presentaba antecedentes alérgicos al inicio del tratamiento.Resultados: La incidencia de reacciones adversas a los MCI entre nuestros pacientes tratados con IL-2 fue 7,14 por ciento (de 168 pacientes). Esta cifra difiere significativamente (p < 0,001) de la del grupo control (1,28 por ciento de 544 pacientes). Así los pacientes tratados con IL-2 presentan un riesgo relativo 5,6 veces mayor (IC 95 por ciento; 2,2-13,9) de padecer una reacción adversa con respecto a los no tratados. La mayor parte de estas reacciones adversas en los pacientes tratados con IL-2 fueron leves y evolucionaron favorablemente sin tratamiento en 11 pacientes.Un paciente requirió hidratación intravenosa forzada por hipotensión.Conclusiones: La IL-2 (potente estimulador del sistema inmune) debe considerarse factor de riesgo para el desarrollo de reacciones de hipersensibilidad u otras reacciones adversas a los MCI.El conocimiento de este hecho debe ser tenido en cuenta en las decisiones y en las estrategias de seguimiento del paciente en el Servicio de Radiología (AU)

Renal failure and iodinated contrast media. A review.

Contrast medium-induced renal failure is reported to be a very frequent adverse effect (up to 70% incidence) that often goes undetected. Consequences are sometimes very dramatic and can even lead to irreversible renal damage and renal dialysis. Basically, four groups of mechanisms will be considered: decrease of renal perfusion and increased vascular resistance, glomerular injury, tubular injury, and obstructive nephropathy. Many risk factors are discussed, but the most important is believed to be preexisting renal insufficiency. Preventive measures are discussed. Principally, maintaining good hydration of the patient and avoiding supplementary risk factors in excess of a possible preexisting renal damage are advocated.

Medios de contraste, cómo usarlos? Estudio de reacciones indeseadas, su prevención y tratamiento / Contrast media, how to use them?: adverse reactions, prophylaxis and treatment

Se presenta un trabajo sobre medios de contraste iodados y sus efectos adversos, poniéndose énfasis en el concepto de premedicación, tratamiento de las reacciones y consentimiento informado

Medios de contraste, cómo usarlos? Estudio de reacciones indeseadas, su prevención y tratamiento / Contrast media, how to use them?: adverse reactions, prophylaxis and treatment

Se presenta un trabajo sobre medios de contraste iodados y sus efectos adversos, poniéndose énfasis en el concepto de premedicación, tratamiento de las reacciones y consentimiento informado (AU)

Nephrotoxicity of high-dose gadolinium compared with iodinated contrast.

To determine if high-dose gadolinium chelates are less nephrotoxic than iodinated contrast. Records of 342 patients who had received high-dose gadolinium (.2 to .4 mmol/kg) for magnetic resonance imaging were reviewed to identify patients who had also received iodinated contrast for radiographic examinations. Their clinical course and laboratory data were reviewed to identify changes in serum creatinine attributable to the contrast agents. In 64 patients, serum creatinine data were available pre and post both gadolinium and iodinated contrast. The mean change in serum creatinine after gadolinium in these 64 patients was -.07 mg/dL (-6 mumol/L). By comparison, the mean change in serum creatinine in the same patients after iodinated contrast was .35 mg/dL (+31 mumol/L) from 2.0 +/- 1.4 to 2.3 +/- 1.8 (P = .002). Eleven of the 64 patients had iodinated contrast-induced renal failure (.5 mg/dL or greater rise in serum creatinine); none had gadolinium contrast-induced renal failure despite the high gadolinium dose and high prevalence of underlying renal insufficiency. High-dose gadolinium chelates are significantly less nephrotoxic than iodinated contrast.