Changes in risk of immediate adverse reactions to iodinated contrast media by repeated administrations in patients with hepatocellular carcinoma

Delayed hypersensitivity reactions to iodinated contrast media: A diagnostic approach by skin tests

BACKGROUND

Adverse drug reactions to iodinated contrast media (ICM) have risen due to their increasing use in x-ray-based imaging modalities. Delayed hypersensitivity reactions are mainly caused by nonionic monomeric compounds and represent an issue impacting the diagnostic-therapeutic pathways of cancer, cardiology and surgery patients.

OBJECTIVES

To prospectively evaluate the usefulness of skin tests in delayed hypersensitivity reactions to ICM and to evaluate the tolerability of iobitridol, a monomeric nonionic low osmolality compound, as a possible safe alternative.

METHODS

Patients with delayed hypersensitivity reactions to ICM referred to us from 2020 to 2022 were prospectively enrolled in the study. All patients underwent patch test and, if negative, intradermal test with the culprit ICM and iobitridol as alternative.

RESULTS

A total of 37 patients (females 24, 64.9%) were enrolled in the study. Iodixanol and iomeprol were the most frequently involved ICM (48.5% and 35.2%, respectively); 62.2% of patients presented maculopapular eruption, while 37.8% reported delayed urticaria-like rash. Skin tests resulted positive to the culprit ICM in 19 patients (51.4%), 16 to patch test and 3 to intradermal test. Skin tests with iobitridol, tested as alternative, resulted positive in 3/19 patients (15.8%). All 16 patients with negative results to iobitridol were administered this ICM and tolerated it.

CONCLUSIONS

In at least half of patients, delayed-type hypersensitivity was demonstrated by skin tests, particularly by patch test. This diagnostic approach resulted simple, cost-effective and safe, not only to confirm the culprit ICM but also to identify iobitridol as feasible alternative.

Clinical features and risk factors of iodinated contrast media (ICM)-induced anaphylaxis

PURPOSE

To evaluate the clinical features and risk factors of iodinated contrast media (ICM)-induced anaphylaxis.

METHODS

This retrospective study included all patients undergoing contrast-enhanced computed tomography (CT) with intravenous ICM administration (iopamidol, iohexol, iomeprol, iopromide, ioversol) at our hospital between April 2016 and September 2021. Medical records of patients who experienced anaphylaxis were reviewed, and the multivariable regression model using generalized estimating equations was employed to eliminate the effect of intrapatient correlation.

RESULTS

Of the 76,194 ICM administrations (44,099 men [58 %] and 32,095 women; age, median, 68 years) to 27, 696 patients, anaphylaxis occurred in 45 cases in 45 different patients (0.06 % of administration and 0.16 % of patients), all with onset within 30 min after administration. Thirty-one (69 %) had no risk factors for ADRs, including 14 (31 %) who had previously used the same ICM that caused anaphylaxis. Thirty-one patients (69 %) had a history of ICM use without any ADRs. Four patients (8.9 %) received oral steroid premedication. The only factor associated with anaphylaxis was the type of ICM, with an odds ratio (OR) of 6.8 (p < 0.001) for iomeprol with iopamidol as a reference. No significant differences in OR of anaphylaxis were found for patients' age, sex, or premedication.

CONCLUSION

The overall incidence of anaphylaxis due to ICM was very low. More than half of the cases had no risk factors for ADRs and had no ADRs on past ICM administration, although the ICM type was associated with a higher OR.

Role of the alpha-fetoprotein response in immune checkpoint inhibitor-based treatment of patients with hepatocellular carcinoma

PURPOSE

The dynamics of serum alpha-fetoprotein (AFP) level have been found to be a useful predictor of therapeutic responsiveness in patients with hepatocellular carcinoma (HCC). We evaluated whether AFP changes were able to accurately reflect imaging-based responses and predict prognosis in patients receiving therapies including immune-checkpoint inhibitors (ICIs).

METHODS

A total of 108 HCC patients with baseline serum AFP ≥ 20 ng/mL who received ICI-based treatment were included. We evaluated AFP-based responses, coupled with radiographic responses by RECIST, at 6-10 (time-point 1, TP1) and 14-18 weeks (time-point 2, TP2) of therapy in terms of the change of AFP from baseline, with a > 20% decrease or increase in level corresponding to the AFP response and progression, respectively. We examined the correlations between AFP and imaging-based responses, and the prognostic implications of the AFP-based measure.

RESULTS

Based on AFP change, there were 24 and 20 responders and 74 and 24 progressors at TP1 and TP2, respectively. The AFP responders yielded radiological objective responses in 90.9% (10/11) and 93.8% (15/16) of the cases at TP1 and TP2, respectively, compared with only 1.4% and none, respectively, of the AFP progressors at the corresponding times. The agreement between progression by RECIST and increased AFP level at the two time-points was 93.8% and 95.0%, respectively. The accuracy of the AFP-based criterion for predicting radiologic response/progression was comparable at TP1 and TP2. Both "AFP responder" and "AFP progressor" at TP1 or TP2 independently predicted the overall survival of patients (adjusted hazard ratios [95% confidence intervals], 0.360 [0.174-0.743] and 0.315 [0.117-0.850]; and 2.525 [1.362-4.679] and 3.908 [1.563-9.769], respectively).

CONCLUSION

Our study suggests that on-treatment AFP changes can complement imaging findings and provide prognostic information for evaluating patients with AFP-producing HCC treated with ICI-based regimens.

Premedication for Iodinated Contrast Media Induced Immediate Hypersensitivity Reactions

Purpose of the review

Premedication using antihistamines and/or corticosteroids has been widely used to prevent reoccurrence of immediate hypersensitivity reactions (iHR) after iodinated contrast media (ICM). However, efficacy has been debated, especially in high-risk patients. Novel findings on the role and risks of premedication and preventive strategies are summarized.

Recent findings

The rate and severity of iHR occurring despite premedication indicate that premedication is not a panacea and the intensity usually reflects that of the initial reaction. Next, the number needed to treat (NNT) to prevent one serious ICM-mediated event using corticosteroid-based premedication is high and associated with a diagnostic delay. Randomly changing the ICM has been suggested as an additional preventive measure, whilst others used a skin test–based approach to identify a subgroup of ICM allergic patients and negative skin test–based alternatives with a high negative predictive value.

Summary

Growing evidence indicates the need to discriminate between non-allergic iHR that are most likely non-obligatory and susceptible to premedication, and rare type I allergic iHR that can be identified using skin testing, especially in those with a severe iHR. Although premedication reduces reoccurrence of mild iHR, it is not always efficacious and should be balanced against side effects, a high NNT and an uncertain efficacy physicians should not blindly rely on. Future work should evaluate combined approaches of an allergy-driven ICM selection and endotype-driven premedication regimens in patients with non-allergic iHR.

Intradermal Testing With Radiocontrast Media to Prevent Recurrent Adverse Reactions

OBJECTIVE. Adverse drug reactions (ADRs) to radiocontrast media are a significant social and economic burden and are difficult to predict. Because some ADRs to radiocontrast media may be immunologically induced, a skin test with diluted 1:10 radiocontrast media has been used to predict ADRs. However, using this test in clinical practice is difficult because of its low sensitivity. SUBJECTS AND METHODS. This study enrolled 36 patients with a history of immediate ADR to radiocontrast media who visited the Allergy and Asthma Clinic of Severance Hospital from 2017 to 2018. Patients underwent intradermal testing (IDT) with five types of diluted (1:10) and undiluted radiocontrast media (iohexol, iobitridol, iopamidol, iopromide, and iodixanol). The IDT result was regarded as positive if at least one radiocontrast medium elicited a positive reaction. Positivity of IDT and sensitivity to the culprit radiocontrast medium were calculated and compared. For subsequent CT examinations with a radiocontrast medium, the contrast agent eliciting a negative skin reaction in IDT was selected, excluding the previous culprit radiocontrast medium. RESULTS. IDT positivity and sensitivity for the culprit radiocontrast medium at 1:10 dilution were 47.2% and 47.2%, respectively, whereas the positivity and sensitivity for the undiluted radiocontrast medium were 86.1% and 75.0%, respectively. The positivity and sensitivity were higher with frequent radiocontrast medium use or with severe reaction. Of 22 patients who underwent another CT examination with the contrast medium selected on the basis of IDT results, 21 (95.5%) did not experience an ADR. CONCLUSION. IDT to prevent ADR should be performed with undiluted radiocontrast medium. Selecting an alternative radiocontrast agent on the basis of IDT results can be clinically useful to prevent recurrent ADRs to radiocontrast media.

Immediate reactions to iodinated contrast media

BACKGROUND

Immediate hypersensitivity reactions (IHRs) to iodinated contrast media (ICMs) remain a common clinical concern. Positive skin test and basophil activation test results suggest a specific IgE-mediated mechanism in some cases. Skin test and controlled challenge test (CCT) are useful to manage these patients.

OBJECTIVE

To study clinical and allergologic features of IHRs to ICMs in a Spanish tertiary hospital during a 7-year period.

METHODS

Demographic and clinical data concerning the reaction were recorded. Patients treated at the Allergy Department of Hospital General Universitario Gregorio Marañón, Madrid, Spain, underwent skin tests. In those with positive results, CCTs with an alternative skin-test-negative ICM was performed. Global reaction rate was calculated and compared for each ICM.

RESULTS

A total of 342 reactions occurred in 329 patients. Cutaneous symptoms were the most common (87.7%). A total of 196 patients underwent an allergy workup, 15 (7.6%) of whom had positive skin test results. Reactions were more severe in patients with positive vs negative skin test results (grade 1, 46.7% vs 73.6%; grade 2, 33.3% vs 20.9%; grade 3, 20% vs 5.46%; P < .05). Three patients had cross-reactivity to 3 ICMs, all including ioversol and iomeprol. Six patients allergic to iopamidol tolerated ioversol and 1 tolerated iomeprol. Four patients allergic to ioversol and 1 allergic to iomeprol tolerated iopamidol. The global reaction rate was 0.2%, differing for each ICM (iopamidol, 0.14%; ioversol, 0.2%; and iomeprol, 0.4%; P < .001). Positive skin test results were found in a low percentage of patients in whom skin test-based CCT identified an alternative non-cross-reactive ICM. Low-grade cross-reactivity was found, especially between iopamidol and ioversol. Reactions were more severe in patients with positive skin test results. The reaction rate was greater for iomeprol compared with iopamidol (reaction rate, 2.8%) and ioversol (reaction rate, 2%).

CONCLUSION

This study identified a possible underlying specific IgE-mediated mechanism by positive skin test result in a low percentage of patients with IHRs to ICMs. In these patients, the CCT based on skin test results was useful for identifying an alternative non-cross-reactive ICM. More studies are needed to investigate the underlying mechanism in patients with IHRs and negative skin test results.

[Effect of Water Intake on Allergy-like Events Associated with Non-ionic Iodine Contrast Agents]

The use of iodine contrast agents occasionally causes serious allergic symptoms including anaphylaxis. At Kyoto University Hospital to prevent nephropathy we began recommending water intake before and after administration of iodine contrast agents in September 2012. In the present study we investigated the effect of water intake on the incidence of allergy-like events after the use of non-ionic iodine contrast agents. We extracted the occurrence of allergy-like events from the incident report system in our hospital from January 2011 to September 2014, and classified these events into the following 3 grades: 1+ (follow-up); 2+ (medication treatment); and 3+ (hospitalization). The allergy-like incidence rate was calculated for subsequent evaluation according to season and water intake. Allergy-like events significantly decreased from 0.49% before the recommendation of water intake to 0.26% at 1 year and 0.20% at 2 years after implementing the recommendation. The incidence of allergy-like events was significantly higher in summer than in winter before water intake was recommended. After implementing the recommendation, the value for summer significantly decreased to an incidence similar to that of winter. Respiratory and gastrointestinal allergy-like symptoms were dramatically decreased after implementing the recommendation. Water intake may be useful for preventing allergy-like events associated with non-ionic iodine contrast agents, especially during the summer.

Hypersensitivity to contrast media and dyes

This article updates current knowledge on hypersensitivity reactions to diagnostic contrast media and dyes. After application of a single iodinated radiocontrast medium (RCM), gadolinium-based contrast medium, fluorescein, or a blue dye, a hypersensitivity reaction is not a common finding; however, because of the high and still increasing frequency of those procedures, patients who have experienced severe reactions are nevertheless frequently encountered in allergy departments. Evidence on allergologic testing and management is best for iodinated RCM, limited for blue dyes, and insufficient for fluorescein. Skin tests can be helpful in the diagnosis of patients with hypersensitivity reactions to these compounds.