Practice parameters for diagnosing and managing iodinated contrast media hypersensitivity

Abstract

Immediate and nonimmediate hypersensitivity reactions to iodinated contrast media (ICM) have been reported to occur in a frequency of about 0.5%‐3% of patients receiving nonionic ICM. The diagnosis and management of these patients vary among guidelines published by various national and international scientific societies, with recommendations ranging from avoidance or premedication to drug provocation test. This position paper aims to give recommendations for the management of patients with ICM hypersensitivity reactions and analyze controversies in this area. Skin tests are recommended as the initial step for diagnosing patients with immediate and nonimmediate hypersensitivity reactions; besides, they may also help guide on tolerability of alternatives. Re‐exposition or drug provocation test should only be done with skin test‐negative ICMs. The decision for performing either re‐exposition or drug provocation test needs to be taken based on a risk‐benefit analysis. The role of in vitro tests for diagnosis and pretreatment for preventing reactions remains controversial.

Assessment of immediate and non-immediate hypersensitivity contrast reactions by skin tests and provocation tests: A review

“…A recent study suggests a provocation based on a risk benefit analysis. 11 In another recently published algorithm on contrast reactions, a negative skin test radiocontrast provocation is only recommended as a confirmation test for tolerability in case of very severe reactions. 24 However, a radiocontrast provocation could also be useful to differentiate an allergic hypersensitivity reaction from non-allergic hypersensitivity reactions and in case of less severe reactions.…”

“… 8 Immediate reactions to ICM or gadolinium-based contrast media occur within 1 h; however they have been reported to occur up to 6 h after exposure and are based on either IgE-mediated or non-IgE-mediated hypersensitivity. 11 The latter is thought to occur due to direct activation of basophilic granulocytes and mast cells because of the hyperosomolar nature of older types of radiocontrast media, or via complement anaphylatoxins C3a and C5a. 12 Although most IHRs are non-allergic, in case of a severe IHR to ICM the patient is more likely to have an IgE-mediated reaction.…”

Challenges in the diagnostic approach of suspected pulmonary embolism in COVID-19 patients

“…Prophylaxis can also be considered in patients with an eGFR of 30-44 mL/min/1.73 m2 at the discretion of the treating physician [68]. Pre-medication may be recommended in patients with previous hypersensitivity (allergic) reactions [69]. Finally, the ventilation-perfusion (VQ) scan may be considered as an alternative imaging method.…”

Basophil activation testing is useful for the evaluation of life-threatening radiocontrast media anaphylaxis

“…The mechanism of immediate hypersensitivity reactions (IHR) to radiocontrast media (RCM) is not fully elucidated (1,2). Allergic (IgE-mediated) mechanisms may account for >50% of life-threatening IHR, as detected by skin testing (ST) (3).…”

“…Testing was performed to RCMs available in our institution; iodixanol (Visipaque, GE Healthcare Australia Pty Ltd, Sydney, Australia), iohexol (Omnipaque, GE Healthcare Australia Pty Ltd), iopromide (Ultravist, Bayer Australia Ltd, Sydney, Australia), meglumine iotroxate (Biliscopin, Bayer Australia Ltd), and sodium diatrizoate and meglumine amidotrizoate (Urografin, Bayer Australia Ltd). ST was performed to EAACI guidelines (1). BAT was performed in line with our protocol (5) at 1:10000-1:10 dilutions.…”