Bio: Lydia Bennedich Kahn, MD/PhD, is a specialist in forensic pathology and works as a forensic pathologist at the Swedish National Board of Forensic Medicine in Stockholm. She is also a researcher at the Department of Oncology-Pathology at Karolinska Institutet in the field of opioid deaths with studies covering the pathophysiological and pharmacological mechanisms behind opiate toxicity.

Abstract: Determining drug concentrations in postmortem blood is central in intoxication fatalities. However, in opioid cases, interpretation is challenging due to the significant overlap between concentrations in deceased and living individuals, which is largely attributed to substantial interindividual variability in opioid tolerance (1). Accurate diagnosis of fatal opioid poisoning is crucial for forensic investigation and official mortality statistics. Integrating diagnostic biomarkers alongside specific macroscopic and microscopic findings enhances the reliability of forensic assessments in establishing opioid-related deaths. Opioid poisoning is commonly associated with respiratory depression and, in certain cases, pulmonary edema, both of which have been suggested to contribute to or cause death (2). While these phenomena are well documented, their underlying pathophysiological mechanisms remain insufficiently understood (3-4). Biomarkers present in pulmonary fluid may serve as valuable tools for differentiating opioid-induced pulmonary edema (OIPE) from edema of known etiology, thereby facilitating a more precise determination of cause of death in suspected opioid-related fatalities. Macro- and microscopic examinations of lung and brain tissue can provide important pathological evidence for determining the cause of death in opioid-related deaths. Additionally, these findings contribute to a more comprehensive understanding of the underlying pathophysiological mechanisms involved in opioid poisoning.

References: 

1. Darke S, Zador D. Fatal heroin 'overdose': a review. Addiction. 1996 Dec;91(12):1765-72.

2. Dolinak D. Opioid Toxicity. Acad Forensic Pathol. 2017 Mar;7(1):19-35.

3. Dettmeyer R, Schmidt P, Musshoff F, Dreisvogt C, Madea B. Pulmonary edema in fatal heroin overdose: immunohistological investigations with IgE, collagen IV and laminin - no increase of defects of alveolar-capillary membranes. Forensic Sci Int. 2000 May 15;110(2):87-96.

4. Mazzotti MC, Teti G, Giorgetti A, Carano F, Pelletti G, Pascali JP, Falconi M, Pelotti S, Fais P. Insights in opiates toxicity: impairment of human vascular mesenchymal stromal cells. Int J Legal Med. 2023 Jul;137(4):1039-1049.