Determination of specific IgE in pericardial and cerebrospinal fluids in forensic casework

- Postmortem identification of IgE-mediated fatal anaphylaxis is challenging.
- Total and specific IgE postmortem measurement is reliable for diagnostic purposes.
- IgE distribution in pericardial and cerebrospinal fluid was rarely investigated.
- Total and specific IgE can be measured in the pericardial fluid.
- Pericardial fluid can be an alternative to postmortem serum for IgE determination.

The aim of this study was to characterize total and specific IgE distribution in postmortem serum as well as pericardial and cerebrospinal fluid samples and evaluate the diagnostic usefulness of total and specific IgE determination in pericardial and cerebrospinal fluids in the forensic setting. Three groups were investigated (non-allergic deaths in non-atopic individuals, fatal allergic anaphylaxis deaths and non-allergic deaths in individuals without medical records). In the first group (non-allergic deaths in non-atopic individuals), total IgE concentrations in postmortem serum from femoral blood, pericardial and cerebrospinal fluids were lower than 40, 32 and 11 kU/l, respectively. No specific IgE were identified in any of the sampled fluids. In the second group (fatal allergic anaphylaxis deaths), total IgE concentrations in postmortem serum from femoral blood ranged from 139 kU/l to 818 kU/l, in pericardial fluid from 89 kU/l to 622 kU/l and in cerebrospinal fluid from 4 kU/l to 11 kU/l. A positive Phadiatop® test and specific IgE antibodies >0.35 kU/l were found exclusively in postmortem serum from femoral blood and pericardial fluid. In the third group (non-allergic deaths in individuals without medical records, possibly including atopic individuals), total IgE concentrations ranged from 42 kU/l to 516 kU/l in postmortem serum from femoral blood, from 34 kU/l to 417 kU/l in pericardial fluid and from 3 kU/l to 12 kU/l in cerebrospinal fluid. A positive Phadiatop® test and specific IgE antibodies >0.35 kU/l were found exclusively in postmortem serum from femoral blood and pericardial fluid. These results seem to suggest that total and specific IgE may be measured in postmortem serum from femoral blood and pericardial fluid to estimate total and specific IgE titers at the time of death. Conversely, cerebrospinal fluid total and specific IgE measurement in suspected IgE mediated fatal anaphylaxis cases is of no value for diagnostic purposes.