Postmortem determination of concentrations of stress hormones in various body fluids--is there a dependency between adrenaline/noradrenaline quotient, cause of death and agony time?

Factors Influencing Postmortem Catecholamine Level and Its Correlations With Agony Time and Cause of Death in Medicolegal Autopsy

BACKGROUND

Catecholamines consisting of epinephrine (EP), norepinephrine (NE), and dopamine (DA) are known as a class of chemical neurotransmitters and hormones essential for regulation of physiological processes including stress responses. Many researchers have tried to establish a relationship between postmortem catecholamine level and agony time or underlying cause of death. However, relevant studies have yielded debatable results. This study was performed to determine characteristics of catecholamine distribution in postmortem specimens with various influencing factors and to assess relationships of postmortem catecholamine levels with agony time and cause of death.

METHODS

A total of 114 autopsy cases were analyzed for catecholamine levels and EP/NE ratios in femoral blood, heart blood, and urine specimens. Postmortem catecholamine levels according to sex, age, medical treatments (cardiopulmonary resuscitation [CPR] and EP injection), postmortem interval (PMI), agonal period, manner of death, and cause of death were evaluated.

RESULTS

Close mutual relationships were noted among femoral and heart blood catecholamine levels. There was no correlation between blood and urine catecholamine levels. Catecholamine levels showed no significant differences according to sex, age, or manner of death. Heart EP and heart EP/NE ratio were significantly higher in the group with CPR. Femoral DA, heart EP, heart NE, heart DA, and urine DA were significantly increased in the group with EP injection. Urine NE and urine DA showed significant differences among PMI groups, with both increased over PMI. In correlation analysis, femoral DA and urine NE displayed weak correlations with PMI. Regarding agony time, femoral and heart DA were significantly increased in long agony group compared to those in the short agony group. With regard to the cause of death, multiple comparison analysis for major categories (natural death, injury, intoxication, asphyxia, drowning, and fire death) revealed a significant increase of femoral NE in asphyxia in comparison with injury. In subgroup analysis for the group without EP injection, femoral NE (P = 0.048), femoral DA (P = 0.039), and heart EP (P = 0.021) showed significant differences between PMI groups.

CONCLUSION

Results of this study have important implications for understanding postmortem catecholamine distribution and their mutual associations, influences of clinical and demographic factors, and relationships with agony time and cause of death in Korean population. Although comprehensive demonstration of catecholamine level as stress index was not possible in the present study, the assessment of postmortem catecholamine levels could be used as a supportive tool in classification of agonal status and differential diagnosis of the cause of death in particular cases. Further investigation is needed on this issue.

Forensic Biochemical Markers to Evaluate the Agonal Period: A Literature Review

Currently, forensic research is multidisciplinary with new methods and parameters useful to define the cause and time of death as well as survival/agony times. The identification of biochemical markers able to estimate agonal period has been studied by many forensic researchers. It is known that the estimation of agonal time in different types of death is not always easy, hence our interest in literature's data. The studies analyzed in this review confirm the important role of thanatobiochemistry for the estimation of survival times. Regardless of the death cause, the survival/agony time between the primary event and death influences markers concentrations in biological samples (e.g., blood, urine, cerebrospinal fluid). Different biomarkers can be used for qualitative evaluations in deaths with short and long agony (e.g., C-reactive protein, ferritin, GFAP, etc.). Instead, the quantitative interpretation showed limits due to the lack of reference cut-offs. Thanatobiochemistry is a useful tool to confirm what emerged from autopsies findings (macroscopic and histological analysis), but further studies are desirable to confirm the evidence emerging from our review of the literature.

Vitreous humor endogenous compounds analysis for post-mortem forensic investigation

The chemical and biochemical analysis of bodily fluids after death is an important thanatochemical approach to assess the cause and time since death. Vitreous humor (VH) has been used as a biofluid for forensic purposes since the 1960s. Due to its established relevance in toxicology, a literature review highlighting the use of VH with an emphasis on endogenous compounds has not yet been undertaken. VH is a chemically complex aqueous solution of carbohydrates, proteins, electrolytes and other small molecules present in living organisms; this biofluid is useful tool for its isolated environment, preserved from bacterial contamination, decomposition, autolysis, and metabolic reactions. The post-mortem analysis of VH provides an important tool for the estimation of the post-mortem interval (PMI), which can be helpful in determining the cause of death. Consequently, the present review evaluates the recent chemical and biochemical advances with particular importance on the endogenous compounds present at the time of death and their modification over time, which are valuable for the PMI prediction and to identify the cause of death.

Post-mortem serum concentrations of GFAP correlate with agony time but do not indicate a primary cerebral cause of death

Background and purpose

The astroglial protein GFAP is a blood biomarker indicative of intracerebral hemorrhage in patients with acute stroke. Due to its brain specificity and the necessity of brain damage for its detectability in blood, we hypothesized that GFAP could be an interesting marker in cases with primary cerebral cause of death, e.g., traumatic brain injury.

Methods

All corpses scheduled for an autopsy in the Frankfurt Department of Forensic medicine within a 15-month period were included in the study. Cases with a known history of brain disease in the 3 months before death were excluded. During autopsy, blood was collected and GFAP serum levels were determined using a commercially available ELISA. The autopsy protocols were reviewed for the presence of a primary cerebral or a primary non-cerebral cause of death. Agony time was also determined.

Results

A total of 129 autopsy cases were included. GFAP concentrations did not differ between cerebral (median 0.96 μg/l, IQR 5.03) and non-cerebral causes of death (1.21 μg/l, 3.58). GFAP levels were found to be unaffected by hemolysis or post-mortem interval. GFAP levels were found to be increased in cases with prolonged agony times (median 1.76 μg/l [IQR 4.70]) compared to short (0.58 μg/l [0.58]; p<0.001) and ultra-short agony times (0.21 μg/l [0.12]; p = 0.002).

Conclusion

Post-mortem GFAP serum concentrations correlate with agony time and might therefore be useful for the evaluation of the severity of brain damage in prolonged death. Elevated GFAP serum levels do not indicate a primary cerebral cause of death.

The relationship between the intramuscular bleeding of the tongue and cause of death

Intramuscular bleeding of the tongue (ImBT) is occasionally found during post mortem examination. Despite its frequent reports, its cause has not yet been clarified. In this study, forensic autopsy data of 799 cadavers were examined and the relationship between ImBT and cause of death was investigated. A total of 74 cases showed ImBT (16 of 66 cases of fire fatality, 17 of 108 cases of drowning, 23 of 74 cases of asphyxiation, and 18 of 551 cases of other causes of death). The frequency of bleeding was significantly greater in cases with causes of death including fire fatality, drowning, and asphyxiation compared to those with other causes of death (p < 0.01). Among asphyxiation cases, ImBT was confirmed in two of five cases of typical hanging, three of 16 cases of atypical hanging, six of six cases of ligature strangulation, two of two cases of manual strangulation, eight of 38 cases of airway obstruction, and two of seven cases of oxygen deficiency. Among fire fatalities, the carboxyhemoglobin (CO-Hb) concentration of cases with ImBT was significantly lower than that in cases without ImBT (p < 0.01). In addition, the frequency of bleeding was significantly higher (p < 0.05) in cases where the blood cyanide concentration was 0.05 ppm or less. These observations suggested that ImBT during fire fatality occurs in a manner similar to that of ligature or manual strangulation, in which the flames cause the contraction and decrease in elasticity of the skin. Past reports indicated that bleeding frequency in cases of drowning did not significantly differ from that in cases with other causes of death. However, our cases showed a statistically higher incidence of bleeding compared to that in the other causes of death (p < 0.01). These results suggested that ImBT is a characteristic finding in cases of asphyxia and is an important evaluation for the diagnosis of death. When the relationship between ImBT and petechial hemorrhage was examined in three of the causes of death, no significant difference was observed between fire fatality and asphyxiation, but drowning was significantly different (p < 0.05). In cases without ImBT, the secretion of noradrenaline and adrenaline was significantly higher (p < 0.01). This finding suggests that it is unlikely that excessive secretion of catecholamine causes ImBT.

The association between pro-arrhythmic agents and aortic stenosis in young adults: is it sufficient to clarify the sudden unexpected deaths?

Most young patients with mild-to-moderate aortic stenosis show no symptoms, and sudden death appears only occasionally. We hypothesised that malignant ventricular arrhythmias could be responsible for the high incidence of sudden death in such patients. If multiple factors such as asymptomatic aortic stenosis in association with arrhythmia-provoking agents are involved, could it be sufficient to account for sudden unexpected death? In this study, eight cases of sudden death in young adults, with ages ranging from 22 to 36 years, who had never reported any symptoms that could be related to aortic stenosis, were investigated. Full autopsies were performed, and congenital aortic stenosis in all eight cases was confirmed. DNA testing for channelopathies was negative. Comprehensive toxicological analyses found an electrolyte imbalance, or non-toxic concentrations of amitriptyline, terfenadine, caffeine, and ethanol. Collectively, these results suggest that congenital asymptomatic aortic stenosis without cardiac hypertrophy in young adults is not sufficient to cause sudden death merely on its own; rather, an additional provoking factor is necessary. According to our findings, the provoking factor may be a state of physical or emotional stress, a state of electrolyte imbalance, or even taking a therapeutic dose of a particular drug.

Glucocorticosteroids as markers of death from hypothermia

In the course of hypothermia, biochemical changes occur that are associated with stimulation of protective thermogenic mechanisms as well as mobilization of internal energy resources mediated by the hormone system. The objective of the investigation was the assessment of validity of determinations of cortisol, cortisone and corticosterone as hypothermia markers in cases of fatal hypothermia combined with concomitant insobriety of the victims. The experimental group consisted of blood samples collected in the course of medico-legal autopsies of 23 hypothermia victims. The controls included blood samples originating from 34 victims of violent sudden deaths (deaths by hanging and traffic road accidents at the scene) and from ten individuals deceased after prolonged agony in consequence of post-traumatic subdural hematomas. In both groups, three subgroups were distinguished that included cases with ethanol levels within the following ranges: 0.0-0.99, 1.0-2.99 and ≥3.0‰. The comparison of determination results showed that irrespectively of blood ethanol concentration, cortisol, cortisone and corticosterone levels seen in hypothermia victims were significantly higher as compared to the controls (P<0.001).

Evaluation of the agonal stress: can immunohistochemical detection of ubiquitin in the locus coeruleus be useful?

The determination of the survival time after a crime as well as the concomitant physical and mental load of the victim is an important task for the forensic pathologist. The heat shock protein, ubiquitin, exerts an essential role in the cellular response to stress. We aimed to investigate the usefulness of the ubiquitin expression in the locus coeruleus as a marker for the evaluation of agonal stress. Is the amount of ubiquitin in this brain locus an indication of the length and/or intensity of the agonal period following various causes of death? The immunohistochemical (IHC) expression of ubiquitin is examined in formalin-fixed, paraffin-embedded slides of the human locus coeruleus (n = 48). The evaluation of the IHC staining is blindly performed, prior to the study of the medico-legal files. According to the length of agony, a division into subgroups is made. Three possible IHC staining patterns are observed: a staining of the neuronal nucleus or the cytoplasm or both. In addition, the number of neurons with ubiquitin expression per μm(2) is calculated in each locus coeruleus. Significant differences in the number of ubiquitin-immunoreactive neurons are noticed with respect to the length of the agony: A higher density of positive neurons is seen in case of a pronounced and extended death struggle.