SAN DIEGO – Patients with food allergies – including those with a history of anaphylaxis – had no adverse reactions to propofol administered for anesthesia during endoscopy, based on a study that included 160 patients with food allergies.
Intravenous propofol (2,6-diisopropylphenol) includes lipid suspensions that contain egg lecithin/phosphatide and soy oil, ingredients that have raised "concern regarding administration of propofol in patients with egg and soy allergy," explained Dr. Harshna Mehta, a pediatric allergist-immunologist at the Icahn School of Medicine at Mount Sinai, New York. "Additionally, since the peanut is a legume similar to soy, there is also potential concern for peanut allergic patients."
Case reports of propofol-associated allergic reactions – presumably related to cross-reactivity to foods – have appeared in the medical literature. "However, most of these cases lacked confirmatory testing for actual food allergy vs. mere sensitization," Dr. Mehta said in an interview before the annual meeting of the American Academy of Allergy, Asthma, and Immunology, where the study results were presented.
Prior to this study, the largest study included 28 egg allergic patients, with two having a history of anaphylaxis (Anesth. Analg. 2011;113: 140-4).
Dr. Mehta and her associates reviewed the records of 563 patients who had endoscopies performed at the Mount Sinai Center for Eosinophilic Disorders from November 2004 to January 2014.
The researchers identified 160 patients with a median age of 14 years who had one or more food allergies, including 31 with a history of anaphylaxis. Egg, peanut, and soy allergies were confirmed based on finding elevated food specific serum IgE levels, positive skin prick tests and/or convincing allergic reaction history. Patients were included in the study if anesthesia records indicated propofol as the chief anesthetic administered.
Of the 160 patients, 95 had evidence of egg allergy (median egg-IgE = 9.57 kIU/L); 15 of these patients had a history of an anaphylactic reaction to egg. Of the 28 patients with confirmed soy allergy (median soy-IgE = 6.63 kU/L), 2 had a history of anaphylaxis. Dr. Mehta also reported that 117 patients had peanut allergy (median peanut-IgE =38.8 kIU/L); 11 o these patients had a history of anaphylaxis to peanuts.
There were no reported reactions to propofol in any of the patients.
"The most surprising finding was the number of egg/peanut/soy patients who have significant allergic comorbidities – such as history of anaphylaxis, allergic rhinitis, asthma, and atopic disease – that have safely received this medication," Dr. Mehta noted. "We are still in the process of determining the statistical confidence with which we can say how safe propofol is for administration to egg/soy/peanut allergic patients. We are also planning to test the product in the laboratory for the presence of egg protein."
Dr. Mehta said that she had no relevant financial conflicts to disclose.