Diagnosis and Prevention of Hypersensitivity Reactions to Iodinated Contrast Media

Abstract

Iodinated contrast media (ICM) have become one of the major causes of drug hypersensitivity reactions (HSRs) related to increasing numbers of ICM-based radiological imaging procedures. Strategies for diagnosing and preventing ICM-induced HSRs have not been uniformly standardized yet. However, advances have been made based on the results of recent research. A previous history of hypersensitivity to ICM is the most significant risk factor for developing HSR by ICM. Avoidance of culprit agents and premedication is the main strategy to prevent recurrences of HSRs in high-risk patients. In addition, we strongly recommend identifying sensitized ICM using skin tests to determine immunoglobulin E-mediated or delayed-type allergy and to guide the choice of an alternative contrast agent. ICM provocation test procedures have been established and are helpful in selected cases. In this paper, we review how to evaluate patients who have experienced immediate or delayed HSRs caused by ICM to minimize the risk of recurrence and discuss unmet needs that require further research.

Contrast allergies for neurological imaging: When to proceed

“…Skin tests and drug provocation tests may be helpful for patients with a history of reaction to contrast when imaging without contrast is not an option [ 20 , 28 , 38 , 40 , 44 , 48 ]. For patients with a history of immediate reactions who have records or knowledge of which contrast agent caused their reaction, a skin prick test can be used to determine which other contrast agents may be safe to use as alternatives [ 20 , 28 , 40 , 44 , 48 ].…”

“…Skin tests and drug provocation tests may be helpful for patients with a history of reaction to contrast when imaging without contrast is not an option [ 20 , 28 , 38 , 40 , 44 , 48 ]. For patients with a history of immediate reactions who have records or knowledge of which contrast agent caused their reaction, a skin prick test can be used to determine which other contrast agents may be safe to use as alternatives [ 20 , 28 , 40 , 44 , 48 ]. For patients who do not know which contrast agent they reacted to, an intradermal test should be performed as a panel to determine which contrast likely caused the reaction, followed by a skin prick test to determine which other agents are likely safe to use [ 20 , 28 , 40 , 44 , 48 ].…”

“…For patients with a history of immediate reactions who have records or knowledge of which contrast agent caused their reaction, a skin prick test can be used to determine which other contrast agents may be safe to use as alternatives [ 20 , 28 , 40 , 44 , 48 ]. For patients who do not know which contrast agent they reacted to, an intradermal test should be performed as a panel to determine which contrast likely caused the reaction, followed by a skin prick test to determine which other agents are likely safe to use [ 20 , 28 , 40 , 44 , 48 ]. Patients with a history of mild delayed reactions to contrast should have either a patch test or an intradermal test that is read after 24–48 hours to confirm allergy to the specific contrast agent, followed by a skin prick test to determine potentially safe alternatives [ 20 , 28 , 40 , 44 , 48 ].…”

“…For patients who do not know which contrast agent they reacted to, an intradermal test should be performed as a panel to determine which contrast likely caused the reaction, followed by a skin prick test to determine which other agents are likely safe to use [ 20 , 28 , 40 , 44 , 48 ]. Patients with a history of mild delayed reactions to contrast should have either a patch test or an intradermal test that is read after 24–48 hours to confirm allergy to the specific contrast agent, followed by a skin prick test to determine potentially safe alternatives [ 20 , 28 , 40 , 44 , 48 ]. While skin tests offer promise as a potential screening and diagnostic tool in high-risk patients, there is still limited and mixed evidence to support their efficacy.…”

“…While skin tests offer promise as a potential screening and diagnostic tool in high-risk patients, there is still limited and mixed evidence to support their efficacy. The variable sensitivities between studies could be problematic as patients could still suffer a severe reaction to a contrast agent despite a negative skin prick test [ 20 , 28 , 31 , 40 , 44 , 48 , 66 – 73 ]. However, skin tests should be completed to ensure that allergic reactions are not missed [ 31 , 48 ].…”