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Insulin injection sites: morphology and immunohistochemistry

R Lutz1, I Pedal, C Wetzel

  • 1Institute of Forensic Medicine, University of Heidelberg, Germany.

Forensic Science International
|January 23, 1998
PubMed

Insights

Insulin was detected in injection sites 24 days after a non-diabetic woman

Area of Science:

  • Forensic pathology
  • Toxicology
  • Endocrinology

Background:

  • Detection of exogenous insulin in forensic investigations is crucial for determining the cause of death.
  • Standard histological techniques can be challenging for preserving and detecting protein-based substances like insulin.

Observation:

  • Insulin was identified in formalin-fixed, paraffin-embedded subcutaneous injection sites 24 days post-mortem.
  • Birefringent crystalline material, likely zinc phosphate, was observed.
  • Immunohistochemistry revealed granular insulin deposits and insulin staining on lipocyte membranes.

Findings:

  • Granular insulin depots and membrane-bound insulin were visualized using immunohistochemistry.
  • A granulocytic inflammatory cellular reaction with insulin uptake by inflammatory cells was present.
  • Insulin was successfully detected despite a significant post-mortem interval and routine tissue processing.

Implications:

  • This study demonstrates the feasibility of detecting insulin in fixed tissues long after death.
  • The findings support the utility of immunohistochemistry in forensic toxicology cases involving insulin.
  • This method can aid in confirming insulin administration in cases of suspected suicide or homicide.

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