Iodinated contrast media allergy is rare in patients undergoing sialography

Iodinated contrast media allergy is considered as a strong contra-indication for performing sialography. There is little evidence to support this approach.

To evaluate the rate of iodinated contrast media (ICM) allergy in subjects undergoing sialography and to assess the risk for allergic responses in patients with a previous diagnosis of allergy.

We retrospectively reviewed sialo-CBCT studies performed from 2014 to 2019. During the study period we implemented a protocol for performing sialo-CBCT in patients with a prior diagnosis of allergy: 1) Clinical data were collected from a questionnaire and medical records. 2) No premedication was administered but, instead, oxygen, epinephrine and a resuscitation cart were accessible. 3) Following the procedure, each patient was observed for one hour and contacted by telephone 24 hrs later.

No allergic responses were documented in the medical records of 1515 subjects following sialo-CBCT studies, including 13 individuals previously diagnosed with ICM allergy. Investigation of the subgroup with prior allergy disclosed that the range of injected volume was between 2 ml to 6.2 ml per patient and that complete secretion of ICM was detected in 7 of 13 patients. In the remainder of subjects, retention rates of 5-50% were observed.

Allergic reactions are exceedingly rare following sialo-CBCT studies regardless of a previous diagnosis of allergy. Pre-medication with corticosteroids and antihistamines is usually not warranted.