[Serum tryptase: marker of occupational anaphylaxis]

Tryptase is a protein released by mast cells, which is involved in the enhancement of inflammatory sequences in immune-mediated reactions. According with our experience, some patients having a reaction clinically classified as anaphylaxis, showed high levels of tryptase (> 20 ng/l) but also of serum specific IgE, showing the immune-mediated nature of the reactions. On the other hand workers without specific IgE and with low levels of tryptase probably had developed pseudoallergic (anaphylactoid) reactions. So, tryptase can be used as biomarker of occupational anaphylaxis and appear to be able to make out immune and nonimmune mediated reactions.