Effects of refrigeration on the biometry and development of Protophormia terraenovae (Robineau-Desvoidy) (Diptera: Calliphoridae) and its consequences in estimating post-mortem interval in forensic investigations

The aim of this study was to simulate the low temperatures that insects could experience between the time being sampled from cadavers and their arrival in the laboratory. This was in order to investigate the effect of low temperature on development of maggots. At different stages of development, individuals of Protophormia terraenovae (Robineau-Desvoidy) reared at 24 degrees C were submitted to a temperature of 4.0+/-0.5 degrees C for a period varying from 1 to 10 days. Independent of the stage of development at which the insects were refrigerated, the treatment induced significant changes on the duration of development. The effect of low temperature on the developmental time between the return to 24 degrees C to adult emergence depended on the larval stage that was refrigerated. When first instar larvae and prepupae were refrigerated, the time to emergence at 24 degrees C decreased with an increase of duration of the refrigeration period. Time to emergence increased under the same conditions when second instar larvae and pupae were refrigerated. These results indicate that keeping larvae of P. terraenovae at 4 degrees C does not just simply lead to a cessation of metabolism but disturbs the regular development. Ten days of cooling induced an error in estimating post-mortem interval (PMI) of more than 6h.     

Increased lung weight in fatal intoxications is not unique to opioid drugs

Fatal intoxications with opioids are known to be associated with an increased lung weight, as well as with brain and pulmonary edema and urinary retention. However, there is evidence to suggest that fatal intoxications with non-opioid substances are also associated with increased lung weight; however, the latter aspect has not been comprehensively analyzed. To determine to what extent opioid and non-opioid substances are associated with increased lung and brain weight, we studied these organs in cases where the cause of death was attributed to intoxication with a single agent. Using data from cases autopsied at the National Board of Forensic Medicine (NBFM) in Sweden from 2009 through 2019 where the cause of death was attributed to a single substance, we created models of combined lung weight and brain weight. The models used age and sex as predictors as well as nested varying effects for the specific intoxicant and category of intoxicant. Suicidal hanging with negative toxicology cases served as controls. The population majority was male among both intoxications (68%) and controls (83%). The most common single substance group was opioids. All tested substances were associated with heavier lungs than controls, with the largest effect in the opioid group. Our findings show that several substances are associated with increased lung weight and that among intoxication deaths there is no difference in expected brain weight between substances. Hence, heavy lungs, without a reasonable explanation, should prompt a broad toxicological screening.     

Suicide of an adolescent girl with sodium nitrite ordered on the internet

Nitrites are commonly used in the chemical, pharmaceutical, and food industries. Recently, they have been identified in cases of voluntary intoxication. We report the case of a 13-year-old girl who was found lifeless on her bed next to a glass containing a white powder and a bottle containing a white powder with a moistened appearance. External examination and autopsy revealed a nonspecific asphyxia syndrome, which was confirmed by the pathological analysis. Analysis of the samples revealed metoclopramide in the peripheral blood at a concentration of 0.402 mg/L (LC–HRMS). An analysis of the gastric contents was carried out after sodium nitrite was detected in the powders found near the body (Raman spectrometry). Nitrites were found in the gastric fluid at a concentration of 30.9 mg/L. Death occurred secondary to anoxia, following ingestion of nitrites; suicide kits are available on the web and nitrites are relatively easy to source and inexpensive. Nitrites are delivered in powder form to be dissolved in liquid, which may then be consumed with metoclopramide (or an alternative anti-emetic drug) to maximize absorption and reduce emesis. The toxic effect of nitrites lies in their oxidizing power, causing the transformation of hemoglobin into methemoglobin, which, when it accumulates, induces tissue anoxia resulting in death. There has been an alarming increase in the number of cases linked to suicide using nitrites or a nitrite suicide kit. The fact that nitrites are readily available online underscores the importance of establishing effective preventive measures such as limiting the access and use of this chemical.     

Subnuclear renal tubular vacuoles in alcohol use disorder

Subnuclear vacuoles in the proximal renal tubules have been reported as a histologic sign of ketoacidosis. Originally described in diabetic ketoacidosis, renal vacuoles can be found in other ketogenic states such as alcoholic ketoacidosis (AKA), starvation, and hypothermia, underpinned by deranged fatty acid metabolism. A retrospective analysis of 133 deaths associated with alcohol use disorder (AUD) examined at autopsy between 2017 and 2020 was undertaken. This study aimed to determine the prevalence of subnuclear vacuoles in deaths of those with AUD and their specificity for deaths from AKA, and to elucidate what demographic, biochemical, and pathologic findings are associated with subnuclear vacuoles. In each case, vitreous humor biochemistry including electrolytes, glucose, and beta-hydroxybutyrate (BHB) was analyzed alongside postmortem hemoglobin A1c and renal and liver histology. Renal histology was graded for the presence of vacuoles as absent (0), scanty (1), or easily identifiable (2). Liver histology was graded for steatosis and for fibrosis if Masson trichrome staining was available. Vacuoles were commonly seen in the deaths of those with AUD. They were seen in deaths due to AKA but were not specific to that cause of death. With vacuoles present, lower vitreous sodium (139 vs. 142 mmol/L; p = 0.005), higher vitreous BHB (1.50 vs. 1.39 mmol/L; p = 0.04), severe hepatic steatosis, and severe hepatic fibrosis were seen, compared with those without renal vacuoles.     

A retrospective analysis of cardiovascular deaths: A 5-year autopsy study of 1045 cases in Antalya,Turkey

This study aims to identify the macroscopic and microscopic changes that occur in the heart in different causes of cardiovascular death and sudden cardiac death in autopsy cases and evaluate the difficulties that a forensic practitioner may encounter during autopsies. All forensic autopsy cases in the Morgue Department of the Council of Forensic Medicine, Antalya Group Administration between January 1, 2015, and December 31, 2019, were examined, retrospectively. The cases were chosen according to inclusion and exclusion criteria, and their autopsy reports were examined in detail. It was determined that 1045 cases met the study criteria, 735 of which were also met the sudden cardiac death criteria. The top three common causes of death were ischemic heart disease (n = 719, 68.8%), left ventricular hypertrophy (n = 105, 10%), and aortic dissection (n = 58, 5.5%). The frequency of myocardial interstitial fibrosis was significantly higher in deaths due to left ventricular hypertrophy than in deaths due to ischemic heart disease and other causes (χ²(2) = 33.365, p < 0.001). Despite detailed autopsy and histopathological examinations, some heart diseases that cause sudden death may still not be detected.