The aim of this study was to characterize the concentrations of total and specific IgE as well as mast cell-derived tryptase in postmortem serum from femoral blood and evaluate the usefulness of their determination for diagnostic purposes in cases of fatal asthma attacks. 36 autopsy cases were retrospectively selected including cases of witnessed death in asthmatic subjects, deaths in asthmatics and atopic subjects with causes of death unrelated to asthma or allergic anaphylaxis as well as deaths in non-atopic, non-allergic individuals with causes of death unrelated to asthma or allergic anaphylaxis. Initial results indicated increased postmortem serum total IgE in atopic and asthmatic individuals, irrespective of the cause of death. Conversely, increased mast cell tryptase levels were noted exclusively in fatal asthma attacks. This suggests that mast cell tryptase measurement in cases of death potentially caused by severe acute bronchial asthma may be useful for diagnostic purposes.