Gender risk for anaphylactoid reaction to radiographic contrast media

Female predominance has been reported previously in series of anaphylaxis cases; however, no definite precedent has been established for greater risk of anaphylactoid reaction caused by contrast media infusion on the basis of gender.

This study was designed to determine whether greater risk for anaphylactoid reaction caused by intravenous contrast media infusion exists in association with female gender.

Rates of anaphylactoid and severe anaphylactoid reaction, according to gender, were determined in a sample of 5264 consecutive patients receiving conventional radiocontrast media during performance of computed tomography.

Of 80 adverse reactions caused by contrast media infusion, 73 (1.39%) were classified as anaphylactoid in nature. Among 5191 patients who received intravenous contrast media without experiencing an anaphylactoid reaction, there were 2642 male patients (51%) and 2549 female patients (49%); reactors included 22 male patients and 51 female patients (odds ratio = 2.40, 95% confidence interval = 1.42-4.10, p < 0.0005). Female patients also comprised 21 of 22 cases of severe anaphylactoid reaction (odds ratio = 21.77, 95% confidence interval = 3.13-435.12, p < 0.0005).

Greater risk for anaphylactoid and severe anaphylactoid reaction exists in association with female gender. Further studies are needed to identify mechanisms that can explain this risk. The importance of these findings for cost-effective use of lower osmolality contrast media need to be determined.