Utilization of serum tryptase and immunoglobulin e assay in the postmortem diagnosis of anaphylaxis

The postmortem diagnosis of anaphylaxis is difficult. Serum concentrations of tryptase (a mast cell product released during anaphylaxis) have been used after death as an indicator of possible antemortem anaphylaxis. However, studies have indicated that tryptase may be elevated with increasing postmortem interval (PMI), or in nonanaphylactic deaths with significant atherosclerosis or chest trauma. Serum total IgE has been used by some to confirm anaphylaxis when tryptase is elevated. Serum levels of tryptase from 57 decedents with varying PMI, all dying of presumed nonanaphylactic causes, were determined. In cases with elevated levels (>11.4 ng/mL), an assay of total serum IgE was also performed. Both tryptase and IgE demonstrated significant elevations with increasing PMI. Decedents were categorized according to presence of cardiovascular disease, chest trauma, or both; many demonstrated elevation of 1 or both markers, without statistically significant differences between categories. Postulated mechanisms for nonanaphylactic elevations of these markers are reviewed. The possible utility of allergen-specific IgE or allergen panels is discussed.