The negative predictive value of gadolinium skin tests seems to be of value.
Clinical value of negative skin tests to gadolinium contrast agents
Article first published online: 19 AUG 2011
© 2011 John Wiley & Sons A/S
Volume 66, Issue 11, pages 1504–1506, November 2011
How to Cite
Chiriac, A.-M., Audurier, Y., Bousquet, P. .-J. and Demoly, P. (2011), Clinical value of negative skin tests to gadolinium contrast agents. Allergy, 66: 1504–1506. doi: 10.1111/j.1398-9995.2011.02690.x
- Issue published online: 7 OCT 2011
- Article first published online: 19 AUG 2011
- Accepted for publication 21 July 2011
- gadolinium contrast agents;
- negative predictive value;
- skin test
Magnetic resonance imaging (MRI) contrast agents are classically considered to be safe, although anaphylactic reactions have been reported (1). To date, few detailed reports incriminating an IgE-dependent mechanism related to the use of these agents have been published (2–4).
We present the gadolinium contrast agents (GdAs) skin test (ST) results of all consecutive patients who were referred to our allergy department over the last 5 years with a compatible clinical history of GdA hypersensitivity and who were re-challenged after negative STs.
Before performing STs, clinical data were registered using the EAACI-ENDA drug allergy questionnaire (5). The severity of the initial reactions was assessed according to the Ring and Messmer (6) classification (localized reactions will be further referred to as grade 0 reactions). Skin tests were performed in accordance with EAACI-ENDA. Skin prick tests (SPTs) were performed with an undiluted MRI contrast agent and, when negative, were followed by intra-dermal tests (IDT) in the range of 10−3 to the 10−1 dilution of the commercially available contrast media, which, in our experience, proved to be a nonirritant threshold (4). Patients with negative STs (either the suspected GdA or an alternative GdA in the case of a positive ST for the suspected GdA) were contacted and asked standard questions about whether or not they had undergone another gadolinium administration after the allergy work-up and what the outcome was.
From January 2006 to April 2011, STs to GdAs were performed on 27 patients. The severity of the reactions was as follows: 37.0% grade 0 and I, 33.3% grade II, and 14.8% grade III. Three patients (11.1%) presented an isolated bronchospasm and 1 (3.8%) reported a nonimmediate reaction. An immunological mechanism – as documented by positive immediate IDTs – accounted for five cases, three grade III and two grade II reactions, respectively. According to our protocol on GdA hypersensitivity diagnostic procedure, negatively skin-tested GdAs were authorized for future MRIs.
All 27 patients were contacted (100% participation rate), either directly or through their attending physician, after a median time interval since allergy work-up of 26.9 (1–63) months. When asked about subsequent administration of GdA, 12 patients (44.4%) reported lack of indication for a new MRI. In four cases (14.8%), MRI without contrast was preferred.
Eleven patients (40.7%) underwent a new injected MRI (Fig. 1) and, when re-exposed, they all tolerated the negatively skin-tested GdA without reaction (Table 1). The median delay between the STs and the new radiocontrast media (RCM) injection was 6 months (1–23). Data regarding premedication were available in six patients (Table 1).
|Patient #||Age||Sex||Type of exam||Name of culprit GdA||Initial reaction||Grade of initial reaction||Delay (months)*||Skin-tests||Delay (months)†||Premedication||GdA re-injected||Side effects|
|1||71||F||NS||Prohance®||Pruritus, dyspnea||Immediate II||4||Negative||NS||NS||Prohance®||None|
|2||43||F||NS||NS||Urticaria, angioedema||Immediate 0/I||35||Negative||NS||NS||Magnevist®||None|
|9||58||F||Cerebral MRI||MultiHancee®||Urticaria||Immediate 0/I||1||Negative||2||None||MultiHance®||None|
|12||65||F||Breast MRI||Prohance®||Urticaria||Non-Immediate mild||2||Negative||23||antiH1, GCS||Dotarem®||None|
|14‡||42||M||Liver MRI||NS||Maculopapular exanthema||Immediate 0||36||Negative||NS||NS||Magnevist®||None|
|22||60||F||Breast MRI||NS||Dyspnea, cough||Immediate isolated BHR||60||Negative||NS||NS||Magnevist®||None|
|23||58||F||NS||Prohance®||Urticaria, dysphagia||Immediate I||72||Negative||5||None||Prohance®||None|
|25||55||F||Cerebral MRI||NS||Facial erythema||Immediate 0||18||Negative||2||None||Dotarem®||None|
|26§||27||F||Cerebral MRI||NS||Angioedema, dyspnea, hypotension||Immediate III||95||Negative||1||antiH1||Dotarem®||None|
|27||37||F||Cerebral MRI||MultiHance®||Urticaria, dyspnea, abdominal cramps||Immediate II||2||Positive¶||2||None||Dotarem®||None|
The excellent negative predictive value of skin testing in our series is obviously biased by the small sample size and the mild severity of the initial reactions.
Nevertheless, these data allow certain conclusions to be drawn. The patients with severe reactions (#26, with a prior grade III nonIgE-mediated anaphylaxis and #27 with grade II IgE-mediated anaphylaxis) were administered and tolerated a negatively skin-tested GdA. This is in accordance with the reports of others (3), and it underlines the importance of an accurate allergy assessment, principally STs, to document the drug’s involvement and to search for alternatives.
Conclusive evidence on the value of STs in GdA hypersensitivity cannot be inferred on the basis of the scarce cases of positive STs reported in the current literature, because these patients have not been re-injected with the positive ST GdA.
This explorative study is consistent with the ongoing approach in drug allergy work-up, and according to our limited population, the negative predictive value of gadolinium STs appears to be of interest. Further studies should confirm these results.
The authors have no conflict of interest for this study.
- 6Incidence and severity of anaphylactoid reactions to colloid volume substitutes. Lancet 1977;26:466–469., .