Postmortem Tryptase Level in 120 Consecutive Nonanaphylactic Deaths: Establishing a Reference Range as <23 μg/L

Area of Science:

• Forensic pathology
• Biochemistry
• Toxicology

Background:

• Postmortem tryptase is a key biomarker for diagnosing anaphylaxis.
• Elevated postmortem tryptase levels can be influenced by various postmortem factors and sampling techniques.
• Accurate interpretation requires understanding normal postmortem tryptase levels in non-anaphylactic deaths.

Purpose of the Study:

• To establish a reliable reference range for postmortem tryptase levels in non-anaphylactic deaths.
• To investigate the impact of perimortem/postmortem factors on postmortem tryptase levels.
• To validate the recommended blood sampling technique for postmortem tryptase analysis.

Main Methods:

• Analysis of blood samples from 120 consecutive non-anaphylactic deaths using recommended femoral/external iliac vein aspiration.
• Statistical analysis including Student t test, Pearson correlation, and univariate/multivariate analyses.
• Determination of postmortem tryptase reference range using nonparametric methods.

Main Results:

• No statistically significant relationship was found between postmortem tryptase levels and postmortem interval, resuscitation, cause of death, sex, or age.
• The mean (SD) postmortem tryptase level was 8.4 (5.2) μg/L.
• The 97.5th percentile postmortem tryptase reference range in non-anaphylactic deaths was established as <23 μg/L.

Conclusions:

• The recommended blood sampling technique yields reliable postmortem tryptase levels.
• A reference range of <23 μg/L for postmortem tryptase in non-anaphylactic deaths is proposed.
• This reference range aids in the accurate interpretation of postmortem tryptase levels for anaphylaxis diagnosis.