Related Experiment Video
Updated: May 10, 2026
07:22
Basophil Activation Test for Allergy Diagnosis
Published on: May 31, 2021
Nonimmediate hypersensitivity reactions to iodinated contrast media
Enrique Gómez1, Adriana Ariza, Natalia Blanca-López
1Research Laboratory for Allergic Diseases, Carlos Haya Hospital, Malaga, Spain.
Current Opinion in Allergy and Clinical Immunology
|June 8, 2013
Summary
Nonimmediate reactions to iodinated contrast media are typically T-cell mediated. Diagnosis often requires drug provocation testing (DPT) due to limitations in skin testing sensitivity for these hypersensitivity reactions.
Area of Science:
- Immunology
- Allergy and Clinical Immunology
- Pharmacology
Background:
- Nonimmediate hypersensitivity reactions to iodinated contrast media (ICM) are increasingly recognized.
- These reactions are often T-cell mediated, posing diagnostic challenges.
Purpose of the Study:
- To analyze recent findings on the mechanisms of nonimmediate ICM reactions.
- To review advances in diagnostic methods, including skin tests, drug provocation tests (DPT), and lymphocyte transformation tests (LTT).
Main Methods:
- Review of current literature on ICM hypersensitivity.
- Analysis of diagnostic test performance: skin testing, LTT, and DPT.
- Focus on T-cell involvement and improved diagnostic techniques.
Main Results:
- T-lymphocytes play a significant role in nonimmediate ICM reactions.
- LTT shows variable results, but improved with autologous dendritic cells.
- Skin testing has low sensitivity and negative predictive value.
- DPT is well-tolerated, useful, and necessary for diagnosis confirmation.
Conclusions:
- Nonimmediate ICM reactions are predominantly T-cell mediated.
- Skin testing is insufficient for definitive diagnosis due to suboptimal sensitivity.
- DPT is crucial for confirming diagnosis and identifying tolerable alternative contrast media.
Related Concept Videos
01:30Hypersensitivities
Hypersensitivity, also known as a hypersensitivity reaction or allergic reaction, is a condition where the body's immune system reacts abnormally to a foreign substance. Such substances, that cause hypersensitivity are referred to as an allergen, could be something typically harmless to most people, like pollen or certain foods.
Types of Hypersensitivities
Hypersensitivity reactions are categorized into four types: Type 1, Type 2, Type 3, and Type 4. Each type has a distinct mechanism...
Types of Hypersensitivities
Hypersensitivity reactions are categorized into four types: Type 1, Type 2, Type 3, and Type 4. Each type has a distinct mechanism...
01:19Hypersensitivity Reactions: Immune-Complex Reactions
Type III hypersensitivity reactions occur when antigen–antibody complexes form and activate the complement system. Normally, these complexes help the clearance of antigens by phagocytes and red blood cells. However, when large numbers of immune complexes are present, they can deposit in tissues—particularly in the walls of blood vessels—leading to inflammation and tissue injury. These deposits trigger complement activation and neutrophil recruitment, resulting in serum sickness, a systemic...
01:30Radiological Investigation I: X-ray and CT
Radiological investigations, including X-rays and computed tomography (CT) scans, are critical for diagnosing and evaluating various medical conditions. These imaging techniques provide valuable insights into the body's internal structures, aiding in the detection of abnormalities, assessment of disease progression, and development of treatment strategies. This article delves into two primary radiological investigations, chest X-rays and CT scans, outlining their purpose, procedures, and the...
01:30Drug Toxicity: Allergic Reactions
Drug-related allergies are immune-mediated responses triggered by the administration of pharmacological agents. These hypersensitivity reactions are classified based on the immune mechanisms involved. The four primary types—Type I, II, III, and IV—are mediated by different immunological pathways and exhibit distinct clinical manifestations.Type I Hypersensitivity/ IgE-Mediated Reactions: Immunoglobulin E (IgE) immediately mediates Type I hypersensitivity reactions. Upon initial exposure to a...
01:29Hypersensitivity Reactions: Delayed Hypersensitivity Reactions
Delayed-Type Hypersensitivity (DTH), or Type IV hypersensitivity, is a cell-mediated immune response. It occurs when T cells, rather than antibodies, mediate a reaction to specific antigens. It is characterized by a delayed onset (1-2 days) and involves the recruitment of macrophages to the inflammation site.The initiation of a DTH response begins with the sensitization of T cells. During this phase, which lasts at least 1-2 weeks, antigen-specific T cells are activated, clonally expanded, and...
01:30Allergic Reactions: Anaphylaxis
Anaphylaxis is a severe, life-threatening hypersensitivity reaction mediated by Immunoglobulin E (IgE) antibodies. When IgE binds to allergens, it triggers the release of mediators– histamine, leukotrienes, and prostaglandins from mast cells and basophils. These mediators cause vasodilation, edema, and inflammation, leading to various symptoms.The primary allergens causing anaphylaxis include food items (e.g., peanuts, shellfish), drugs (e.g., penicillin, asparaginase, corticotropin, heparin),...