We evaluated the usefulness of individual
tryptase levels and variations after
adverse drug reactions in 64 patients. Our aim was to find a tool for the diagnosis of
drug allergy. Thirty-seven subjects were confirmed to have
drug allergy, 12 had nonsteroidal anti-inflammatory
drug (
NSAID) reactions, five had negative controlled
drug challenges (NAAR), and 10 had symptoms after placebo intake (PLA). Serum
tryptase levels greatly increased after anaphylactic shocks (2242%) and
anaphylaxis (710.5%). Patients with allergic
urticaria and those with idiosyncratic responses to
acetylsalicylic acid (ASA) exhibited a small increase in serum
tryptase (49.5% and 38.2%, respectively). In the other two groups (NAAR and PLA), no variation in this serum
protease was observed. The time of appearance of the serum
tryptase peak differed considerably among patients with similar clinical reactions (from 30 min to 6 h) and was independent of the latent period, severity of symptoms, or the amount of
tryptase released. We conclude that serum
tryptase determinations are helpful in the diagnosis of
anaphylactic shock and
anaphylaxis, but serial measurements may be needed to confirm mast-cell participation in milder reactions.