Mediators of anaphylactic reactions: Tryptase and histamine stability in whole blood.

Histamine is known to be stable in the plasma obtained after centrifugation up to 4 days at RT for patients and controls.9 According to these results, we suggest that whole blood samples can be stored at +4°C up to 72 hours for histamine and 7 days for tryptase when the laboratory is not available immediately. Tryptase release is considered a robust marker of mast cell degranulation but is not informative in mild reactions and often normal during food-induced allergic reactions.1 Histamine is released at the early beginning of the reaction and may be useful when tryptase levels are normal or not informative. Keywords: histamine; pre-analytic; tryptase; whole blood EN histamine pre-analytic tryptase whole blood 1579 1583 5 05/17/21 20210501 NES 210501 Immediate hypersensitivity reactions are related to mast cell and/or basophil activation. Increased tryptase is defined as >=1.2 × basal value + 2 µg.L SP -1 sp .4 In our hands, tryptase uncertainties of measurement for low and high concentrations (9 µg.L SP -1 sp and 38.2 µg.L SP -1 sp ) are 17% and 16%, respectively, in accordance with published results.5 Plasma histamine concentrations were measured by a radioimmunoassay (Beckman Coulter, ImmunoTech). [Extracted from the article]