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Serum tryptase: an indicator of anaphylaxis following fluorescein angiography
S I Butrus1, G J Negvesky, P M Rivera-Velazques
1Department of Ophthalmology, Washington National Eye Center, DC, USA.
Background:
Anaphylaxis is a potentially fatal complication of fluorescein angiography. It is diagnosed by clinical signs. Serum beta-tryptase serves as a specific indicator of mast cell activation and of anaphylactic shock that can be detected by radioimmunoassay.
Method:
This is a report on a 48-year-old woman who developed anaphylaxis during fluorescein angiography. This study investigates the role of beta-tryptase in anaphylactic shock resulting from intravenous fluorescein angiogram.
Results:
A serum sample of beta-tryptase collected at the time of an adverse reaction to fluorescein angiography was determined by radioimmunassay to be elevated above 20 ng/ml (normal level <1 ng/ml). This indicates massive mast cell activation and anaphylactic shock.
Conclusion:
This case is the first in which elevated levels of beta-tryptase in serum indicated that the systemic adverse reaction to fluorescein was mast cell dependent. Additionally, beta-tryptase levels can be assayed to detect anaphylactic reactions several hours after a precipitating event.
