Anaphylactic Death: A New Forensic Workflow for Diagnosis.

Area of Science:

• Forensic Pathology
• Immunohistochemistry
• Toxicology

Background:

• Anaphylaxis is a rapid, potentially fatal emergency with diagnostic challenges in post-mortem evaluations.
• Establishing certainty in diagnosing anaphylactic death has been a significant forensic challenge.
• Immunohistochemistry and serum tryptase analysis offer new avenues for investigating anaphylactic fatalities.

Purpose of the Study:

• To investigate the utility of immunohistochemical techniques and serum tryptase levels in determining anaphylactic death.
• To analyze autopsy findings in cases of suspected anaphylaxis.
• To establish reliable parameters for the forensic diagnosis of anaphylactic fatalities.

Main Methods:

• Analysis of eleven autopsy cases of anaphylactic death (2005-2017).
• Review of medical records and gross autopsy findings, including pulmonary and airway pathology.
• Measurement of serum tryptase concentrations and immunohistochemical staining for tryptase in lung, pharynx/larynx, and skin samples.

Main Results:

• All cases exhibited pulmonary congestion and edema; 64% had pharyngeal/laryngeal edema.
• Mean serum tryptase was 133.5 µg/L; 100% of lung samples showed strong anti-tryptase staining.
• 80% of skin samples and 30% of pharyngeal/laryngeal samples were also strongly positive for tryptase.

Conclusions:

• A combination of clinical history, serum tryptase >40 µg/L, and positive lung immunohistochemistry for tryptase is reliable for diagnosing anaphylactic death.
• These parameters provide the accuracy required for forensic determination of anaphylaxis as a cause of death.
• Immunohistochemical analysis of tryptase is a valuable tool in the forensic investigation of anaphylactic fatalities.