Adverse reactions to iodinated contrast media: prevalence, risk factors and outcome-the results of a 3-year period.

BACKGROUND: Iodinated contrast media (CM) are commonly used. Hypersensitivity reactions to CM occasionally result in morbidity. Risk factors and the role of premedication remain to be investigated. OBJECTIVE: We sought to explore the prevalence, risk factors and outcome of CM reactions. METHODS: The retrospective case-control study was conducted between 2008 and 2010. In total, 55,286 subjects who were exposed to iodinated CM were enrolled to determine the prevalence of CM reactions. The case-control statistical method was applied to determine the risk factors of CM reactions. 579 subjects who had CM reactions were categorised in the case group and 1,175 of the 55,286 subjects who had tolerated CM exposure were randomised for the control group. RESULTS: The overall prevalence of CM reactions was 1.05%. In a multivariate analysis, the history of previous CM reactions, female gender and the history of seafood allergy were significant risk factors for CM reactions. The significant risk factors for the first episode of CM reactions were female gender, the history of seafood allergy and asthma. We found sixteen serious reactions in the immediate reaction group: ten fully recovered after hospitalisation, five fully recovered after out-patient treatment and one died after the administration of CM via an intra-arterial route during coronary angiogram. The most significant risk factor associated with serious reactions was asthma, whereas comorbid cardiovascular disease, male gender, history of seafood allergy and history of previous CM reactions were significant risk factors for mild reactions. CONCLUSIONS: The prevalence of CM adverse reactions was as low as 1.05%. Risk factors consist of a history of previous CM reactions, female gender and seafood allergy. Nevertheless, serious immediate reactions could occur particularly in patients with asthma.

Comparison of pasteurized whole milk, UHT whole milk, water, and diluted iodine contrast as computed tomographic enteric contrasts.

OBJECTIVE: To compare four computed tomographic (CT) enteric contrasts (pasteurized whole milk, UHT whole milk, water, and diluted iodine contrast) in various aspects, including gastrointestinal (GI) distension, mural visualization, GI landmark distinction, taste, patients 'satisfaction, adverse effects, and prices. MATERIAL AND METHOD: Sixty patients scheduled for whole abdominal CT at the present institution were randomized to receive 1,000 ml of pasteurized whole milk (n = 15), UHT whole milk (n = 15), water (n = 15) and diluted iodine contrast (n = 15) as CT enteric contrasts. Two radiologists separately assessed the GI distension (using a 4-point scale: poor, partial, good, and full), mural visualization (using a 3-point scale: poor, partial, and good), GI landmark distinction at esophagogastric (EG) junction, ampulla of Vater, and pancreatic head-duodenal loop (using a 3-point scale: poor, partial, and good). The participants graded the taste of received enteric contrasts and their satisfaction using a 4-point scale (unacceptable, unpleasant, acceptable, and pleasant). Adverse effects were evaluated by GI associated symptoms (nausea, vomiting, abdominal cramping/discomfort, and diarrhea). RESULTS: Pasteurized whole milk was superior to other agents in GI distension and tended to be better than other agents in mural visualization and GI landmark distinction. No difference in taste and patients' satisfaction was noted between pasteurized whole milk and other agents. Gallbladder collapse was inevitable in participants with pasteurized and UHT whole milk consumption, due to 4%fat content in whole milk. GI adverse effects were more common in whole milk group than other agents. The prices of pasteurized whole milk, UHT whole milk, water and diluted iodine contrast were about 42, 40, 14, and 36 Baht, respectively. CONCLUSION: Pasteurized whole milk is an attractive oral contrast agent, providing good GI distension, mural visualization, and GI landmark discrimination. Apart from gallbladder collapse, increase of GI adverse symptoms was another major drawback of whole milk when used as CT oral contrast, especially in Thai people.