Fluorescein-induced allergic reaction

Background: Adverse reactions following intravenous sodium fluorescein are very unusual and their mechanism is still uncertain. We report the case of a patient who suffered an adverse reaction during a fluorescein ocular angi ography. Positive allergy tests to fluorescein suggest an IgE-mediated mech anism. Objective: Report the allergy evaluation performed in a patient who suffere d an adverse reaction during an intravenous fluorescein administration. Methods: We selected the case of a patient who suffered dizziness, diaphore sis, generalized pallor, nausea, sphincter relaxation, hypotension, and int ense malasie during a fluorescein ocular angiography and compared the resul ts to other nonreactive subjects. Allergy evaluation: Prick and intradermal skin tests and serial determinations of serum tryptase were performed on t he patient and four control subjects who underwent and tolerated the same p rocedure as well as on a patient who developed an intense vagal reaction du ring blood extraction. Results: Positive skin tests and dramatic increase of serum tryptase (67U/I ) were observed in our patient. The rest of the patients had negative skin tests and did not have any variation in their serum tryptase. Conclusions: An IgE-mediated mechanism is suggested as responsible for this adverse reaction. We recommend that a complete allergy evaluation should b e performed in all patients who have adverse reactions to fluorescein in or der to differentiate true allergic reactions from other types of reactions.