Management of hypersensitivity reactions to contrast media

As imaging technologies have become essential for diagnosing various diseases, the use of contrast agents is rapidly expanding. As a result, hypersensitivity reactions (HSRs) to contrast agents have also increased. However, protocols for managing, diagnosing, and preventing these reactions are not fully established yet. Since the guidelines for contrast agent hypersensitivity suggested by domestic and international academic societies are not standardized and sometimes difficult to follow in medical facilities, there is a need for practical recommendations in a real-world setting. This review introduces the strategy to manage, diagnose, and prevent HSRs to contrast agents, which have been successfully implemented at Seoul National University Hospital for a decade. First, every single HSRs should be documented in the medical records because a previous history of hypersensitivity to contrast agents is the most significant risk factor for developing HSR to iodinated contrast media. Secondly, avoidance of culprit agents is the main strategy for preventing recurrences of HSRs to contrast agents. Thirdly, it is important to identify nonsensitized contrast agents using skin tests for future exposure to contrast media. In addition to skin testing, side chains of iodinated contrast media may provide a clue to reactive contrast agents. Fourthly, provocation tests can be performed in selected cases with a nonreactive agent based on the skin testing and side chain commonness. Prior to performing imaging studies, premedication can be applied stratified to the severity of the index HSR. All of these procedures are safe and prove to be executable in the medical facilities.

A successful shortening of desensitization protocol in a patient with cetuximab anaphylaxis

Desensitization therapy can help overcome severe hypersensitivity reactions and allow continuing administration of the culprit agents. However, this is time- and labor-intensive due to a prolonged infusion time and the serial adjustment of infusion rate between steps. Therefore, simplified protocols using fewer steps have been tested, although currently there is no established standard strategy. Cetuximab plays an important role in the treatment of metastatic colorectal cancer. Although cetuximab is well tolerated, severe infusion reactions occur in 1.1% of patients, and most occur within 1 hour of receiving the first dose. Here, we report a recent attempt to shorten the steps of gradual cetuximab desensitization. A 57-year-old male patient diagnosed with obstructive sigmoid colon cancer received cetuximab chemotherapy and experienced immediate anaphylaxis at the first cycle. A one-bag, 17-step desensitization protocol was applied to cetuximab administration. After the first successful desensitization cycle, the process of desensitization was shortened 1–2 step(s) per cycle, down to 2 steps, without a breakthrough reaction. The patient ultimately received regular infusions. Shortening of the rapid desensitization protocol can be considered if the previous cycle is well-tolerated, even in a patient who suffered previous anaphylaxis to cetuximab.

Frequency and clinical characteristics of adverse transfusion reactions in hospitalized patients: A retrospective review of electronic medical records

Purpose@#Adverse transfusion reactions (ATRs) are unfavorable reactions to the transfused unit, and the severity may be different among individuals, depending upon the type of reactions and the patient’s susceptibility. It is necessary to operate and manage a systematic monitoring system to minimize these ATRs and increase the safety. This study was conducted to evaluate clinical features of transfusion-related adverse events and morbidities. @*Methods@#We retrospectively analyzed transfusion data from electronic medical records during the recent 3 years (April 2017 to April 2020) at Seoul National University Bundang Hospital. The electronic search strategy was applied to search for the type of blood products prescribed and identify symptoms that occurred during transfusion as recorded in the nursing chart which is based on the International Classification for Nursing Practice. @*Results@#A total of 18,772 people were transfused during the study period. A total of 524 people were reported as suspected ATRs, of whom 466 were finally confirmed. Red blood cell was the most frequent culprit blood product (59.9%), followed by apheresis platelet (25.1%), fresh frozen plasma (10.1%), and platelet (4.9%). Clinical symptoms included fever (54.9%), urticaria and itching (34.7%), chillness and shivering (21.9%), and chest discomfort (6.0%), dyspnea (5.3%), cold sweating (3.8%), hypotension (2.1%), and palpitations (1.9%). The severity of ATRs were mild (91.8%), moderate (7.1%), and severe (1.1%). @*Conclusion@#ATRs are mostly mild, but life-threatening reactions may occur. Physicians should be aware of various features of ATRs to appropriately recognize and treat such patients.