Distinguishing true from pseudo hematoma in the cervical spinal canal using postmortem computed tomography

Spinal cord injury is difficult to detect directly on postmortem computed tomography (PMCT) and it is usually diagnosed by indirect findings such as a hematoma in the spinal canal. However, we have encountered cases where the hematoma-like high-attenuation area in the cervical spinal canal was visible on PMCT, while no hematoma was observed at autopsy; we called it a "pseudo hematoma in the cervical spinal canal (pseudo-HCSC)." In this retrospective study, we performed statistical analysis to distinguish true from pseudo-HCSC. The cervical spinal canal was dissected in 35 autopsy cases with a hematoma-like high-attenuation area (CT values 60-100 Hounsfield Unit (HU)) in the spinal canal from the first to the fourth cervical vertebrae in axial slices of PMCT images. Of these 22 had a hematoma and 13 did not (pseudo-HCSC). The location and length of the hematoma-like high-attenuation and spinal cord areas were assessed on reconstructed PMCT images, true HCSC cases had longer the posterior hematoma-like area and shorter the spinal cord area in the midline of the spinal canal (P < 0.05). Furthermore, we found that true HCSC cases were more likely to have fractures and gases on PMCT while pseudo-HCSC cases were more likely to have significant facial congestion (P < 0.05). We suggest that pseudo-HCSC on PMCT is related to congestion of the internal vertebral venous plexus. This study raises awareness about the importance of distinguishing true HCSC from pseudo-HCSC in PMCT diagnosis, and it also presents methods for differentiation between these two groups.

An autopsy case of COVID-19-like acute respiratory distress syndrome after mRNA-1273 SARS-CoV-2 vaccination

We report the first case with COVID-19-like acute respiratory distress syndrome after mRNA-1273 SARS-CoV-2 vaccination. An 88-year-old woman developed dyspnea several hours after vaccination with the second dose of mRNA-1273. She was hospitalized on day nine due to worsening dyspnea. Chest computed tomography showed bilateral ground-glass opacities and consolidations, mainly in the peripheral lung areas. Repeat polymerase chain reaction tests for SARS-CoV-2 were negative, although the serum level of antibodies against spike protein was extremely elevated. Her condition did not improve with high-dose corticosteroids and high-flow nasal cannula oxygen therapy; she died on day 18. Autopsy findings revealed very early-phase diffuse alveolar damage in the whole lung without other lung diseases. The clinical and pathological findings suggested vaccine-induced acute respiratory distress syndrome. Serological and pathological tests might be useful to differentiate the disease from COVID-19.

Kinetics and distribution of benzalkonium compounds with different alkyl chain length following intravenous administration in rats

Benzalkonium chloride is widely used in disinfectants. Several toxicological and fatal cases have been reported; however, little is known about its kinetics and distribution. We investigated the kinetic characteristics and distribution of benzalkonium cation (BZK) based on the length of the alkyl chains C12, C14, and C16. Rats were treated intravenously with BZK solution (dose, 13.9 mg/kg) containing equal amounts of the three homologues. Kinetic parameters in the blood were assessed, and BZK distribution in the blood and tissues was examined both in rapid intravenous (IV) and drip intravenous (DIV) administrations. BZK concentrations were analysed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). BZK with longer alkyl chains showed lower elimination tendencies and remained in the blood for a longer duration. Concentrations of BZK were higher in the heart, lung, spleen, and kidney than those in the blood, and lower in the brain and fat. In both the IV and DIV groups, the lung, liver, spleen, and fat samples showed higher concentrations of the longer alkyl chains (BZK-C12 < -C14 < -C16), and the opposite trend was observed in the kidney (BZK-C16 < -C14 < -C12). Only the heart and muscle samples displayed the homologues in ratios comparable to the original administered solutions. Differences between IV and DIV groups could be identified by comparing concentrations of BZK homologues in the heart, lung, spleen, and kidney samples. We found that the kinetics and distribution of BZK were influenced by the alkyl chain length, and analysing each BZK homologues in blood and tissue samples may provide useful information.

The derivation of predictive equations to speculate the post-mortem interval using cases with over 20-mL pleural effusion: A preliminary study

Often, pleural effusion is noted at autopsy when the cause of death is drowning or diseases such as heart, renal and liver failure. Several studies have established a correlation between the concentrations of electrolytes in pleural effusion and the post-mortem interval (PMI) or those concentrations and drowning site. The present study aims to investigate the relationship between the amount of pleural effusion, concentrations of electrolytes and total protein in pleural effusion, by integrated interpretation using various factors such as the deceased's gender, age, cause of death, drowning site, PMI and body temperature. We included 40 cadavers (26 male, 14 female) with >20-mL pleural effusion, which were categorised into four groups as follows: freshwater drowning; brackish water drowning; seawater drowning (drowning group); and not drowning. An equation derived to assess the lung weight revealed that the drowning site affected the lung weight. An equation for the amount of pleural effusion in the drowning group for the first time revealed that the amount of pleural effusion was directly proportional to the PMI. Using an equation to assess the PMI, we could estimate the PMI within 13.0-13.2 h in cases with >20-mL pleural effusion. Despite a small number of cases in the present study, we attained exciting results from the integrated statistical analysis.

Predictive equation for post-mortem interval using spectrophotometric values of post-mortem lividity: A pilot study

The colour of post-mortem lividity and control skin of 86 cadavers was measured spectrophotometrically to obtain L^* (value), a^* (chroma) and b^* (hue) values. In addition, left heart blood (n = 58), right heart blood (n = 57) and blood from the femoral vein (n = 21) were measured. Using these data, we analysed the relationship between post-mortem lividity, control skin and blood colours. L^* of post-mortem lividity (L^*_p) and control skin (L^*_c) were strongly correlated ( r = 0.64). a^* and b^* of post-mortem lividity (a^*_p and b^*_p) significantly increased with an increasing post-mortem interval (PMI) but r² values were low (0.11 and 0.070, respectively). Predictive equations for post-mortem lividity colour (L^*_p, a^*_p and b^*_p) were developed using control skin colour (L^*_c, a^*_c and b^*_c) and autopsy findings for the first time. The predictive equation for L^*_p explained almost 65% of the observed L^*_p. We created predictive equations for PMI with and without blood colour values, and the most accurate equation, which did not use blood colour values, made it possible to estimate PMI within ± 10.29 h. Further study of these equations will help us to understand the factors that affect post-mortem lividity colour and increase the accuracy of equations for predicting post-mortem lividity colour and PMI.

Predictive equation to estimate post-mortem interval using spectrophotometric blood-colour values

Forensic pathologists use post-mortem phenomena to estimate the post-mortem interval (PMI). We have reported on the usefulness of post-mortem lividity spectrophotometric values to estimate PMIs. Here, we focused on blood colour, looking for associations between blood colour, age and PMI. We generated predictive equations for blood-colour values and the PMI. We included data from a total of 129 cadavers (84 males and 45 females). We measured the colour of 124 left ventricular blood ( L*_l, a*_l, b*_l), 123 right ventricular blood ( L*_r, a*_r, b*_r) and 57 femoral blood ( L*_f, a*_f, b*_f) samples. We found no significant associations between blood colour and age or between blood colour and the PMI, but the values of a*_l, b*_l, a*_r and b*_r were significantly increased with increased age, and those of L*_f, a*_f and b*_f were significantly decreased with increased PMI. We created equations to estimate blood colour. The equations for femoral blood colour had higher adjusted R² values and lower root mean square error values than those for left and right ventricular blood colours. We generated equations to estimate PMIs using blood-colour values and autopsy findings. Our estimated PMIs up to 67 hours had accuracies within 8.84 hours, without measuring post-mortem lividity colour or considering the age of the deceased. This is the first study to estimate PMIs based on blood-colour spectrophotometric values.

Detection of imidacloprid in biological fluids in a case of fatal insecticide intoxication

Here, we describe a high-performance liquid chromatography/photodiode array detector method for the detection of imidacloprid in biological fluids in a case of suicide by ingestion of liquor mixed with Admire® Flowable insecticide (containing 20% imidacloprid). A plastic bottle containing a cloudy liquid (concentration of ethanol in the liquid was 150 mg/ml and that of imidacloprid was 50 mg/ml) was found near the decedent. The biological fluids collected at autopsy were prepared by deproteinization with acetonitrile. Zolpidem was used as an internal standard. The concentrations of imidacloprid in femoral blood and cerebrospinal fluid were 105 and 58.5 μg/ml, respectively. Ethanol was also detected in the samples, with concentrations of 1.0 mg/ml in femoral blood and 1.4 mg/ml in cerebrospinal fluid.

Peritoneal bleeding due to percutaneous transhepatic gallbladder drainage: An autopsy report

A 77-year-old man underwent percutaneous transhepatic gallbladder drainage (PTGBD) for acute cholecystitis as a preoperative procedure; however, he suddenly suffered cardiopulmonary arrest 4 h after the PTGBD and died. There were three centesis scars for the PTGBD, and only one pathway from the most dorsal centesis scar reached the gallbladder. Microscopically, the PTGBD pathway crossed and injured the intrahepatic arterial wall, and hepatic parenchymal bleeding extended along the PTGBD pathway to the inferior surface of the liver. Blood flowed to the peritoneal cavity through a small gap between the liver and gallbladder. Consequently, the PTGBD caused lethal bleeding. When the percutaneous transhepatic cholangio drainage/PTGBD pathway runs close to vessels near the liver surface, it might be necessary to deal with the possibility of rapid and lethal peritoneal bleeding.

A transnasal intracranial stab wound by a plastic-covered umbrella tip

A 48-year-old man died from a transnasal intracranial stab wound caused by an umbrella. The track of the stab passed from the right nostril, through the sphenoid sinus, the left side of the sella turcica and anterior clinoid process, and finally reached the surface of the brain. The stab wound crossed the left internal carotid artery, causing an exsanguination and aspiration of blood into the airway, resulting in death. It is extremely rare that an umbrella tip used during a struggle would stab the nostril of the victim. Transnasal intracranial stab wounds can be overlooked and require sensitive handling.

An autopsy case of suction injury

The right upper extremity of a 38-year-old man was entrapped in an underwater intake of a water duct of a dam reservoir, and he died despite being promptly rescued. His right upper extremity was swollen and exhibited purplish-red discolourations. The skin had numerous blisters and increased tension. Severe subcutaneous and muscle bleeding were observed in the right upper extremity. The circumference and volume of the right upper extremity were approximately 1.2 and 1.4 times, respectively, that the circumference and volume of the left upper extremity. The increase in weight of the right extremity was calculated to be approximately 2.1 kg; this finding indicates a severe decrease in the victim's central blood volume. Furthermore, it is possible that much more than 2.1 kg of blood accumulated in the upper extremity upon exposure to vacuum pressure. We conclude that the victim died of circulatory collapse that was attributable to haemorrhage and re-distribution of blood as a result of vacuum pressure on the right upper extremity. Thus, we have examined the cause of death and the effects of vacuum pressure on the human body.

An autopsy case of a primary aortoenteric fistula: A pitfall of the endoscopic diagnosis

A primary aortoenteric fistula (PAEF), defined as a communication between the native aorta and the gastrointestinal tract, is a rare cause of gastrointestinal bleeding. The preoperative diagnosis of PAEF is extremely difficult. Consequently, PAEF may cause sudden and unexpected death. We present an autopsy case of a 68-year-old man who died of massive gastrointestinal bleeding due to a PAEF. Autopsy revealed a pinhole rupture located on the third part of the duodenal mucosa and fistulized into the adjacent abdominal aortic aneurysm (AAA). Our case indicates that the aortoenteric fistula can result in fatal gastrointestinal bleeding. Consequently, a PAEF should be included in the differential diagnosis of gastrointestinal bleeding.

A case of death from the explosion of a 66mm M72 High Explosive Anti-Tank rocket

A 53-year-old male died from an explosion of a 66 mm M72 High Explosive Anti-Tank (HEAT) rocket. He had collected various cast-off military weapons and was selling them. There were numerous explosive injuries on the anterior side of the body, thus especially bilateral hands, left toe and right knee were severely crushed and fractured. The location and severity of the injuries suggest that he was down on his left knee and was manipulating the weapon with both hands at the moment of detonation. We consider that 66 mm M72 HEAT rocket accidentally detonated during his handling. Very rarely are civilians killed by a military weapon, except during wartime. Appropriate investigation of various explosive injuries provide not only evidence of the cause of death, but also the position and posture of the body.

Analysis of oseltamivir active metabolite, oseltamivir carboxylate, in biological materials by HPLC-UV in a case of death following ingestion of Tamiflu®

An HPLC-UV method was established for determination of oseltamivir carboxylate, an active metabolite of oseltamivir, in biological materials. Oseltamivir carboxylate and floropipamide (internal standard) were extracted by using a mixed mode cation exchange extraction cartridge. The recovery yields of oseltamivir carboxylate from spiked blood at concentrations 0.1microg/ml and 1.0microg/ml were 103.8+/-16.9% and 95.0+/-4.3%, respectively. Linearity was obtained in the concentration from 0.1 to 3.0microg/ml. The detection limit was 0.04microg/ml (S/N=3). This method was applied to a case of death from falling after ingestion of a Tamiflu capsule containing 75mg of oseltamivir. Concentration of oseltamivir carboxylate in the femoral blood was 0.4microg/ml. The highest concentration in all specimens was in the liver at 18.3microg/g. In all brain samples, the concentrations were not higher than the quantification limit (0.1microg/g).

[Autopsy case of aspirin intoxication: distribution of salicylic acid and salicyluric acid in body fluid and organs]

A 52 year-old woman ingested approximately 300 tablets (325 mg) of aspirin in a suicide attempt. We analyzed the concentrations of salicylic acid (SA) and salicyluric acid (SUA) in body fluids and organs using a modified previous high-performance liquid chromatographic method. The concentrations of SA in heart and femoral blood were 1.1 mg/mL and 1.3 mg/mL, respectively; the results were far higher than the lethal level. The concentration of SA was 0.3-0.4 mg/g in brain, 0.9-1.4 mg/g in lung, 0.6-0.8 mg/g in liver and 0.9 mg/mL in kidney.

A two-rider motorcycle accident involving injuries around groin area in both the driver and the passenger

This paper presents a two-rider motorcycle accident in which both riders received injuries around the groin area. In medico-legal autopsies, injuries around the groin area in victims of motorcycle accidents are usually regarded as a "fuel tank injury." Although fuel tank injuries are one of the most useful and important characteristics in determining injuries that have been found to be exclusive to the driver, our study reveals that passengers can also suffer from injuries around the groin area. To distinguish the driver from the passenger, we need to carefully consider each injury in both riders. In addition, we present bilateral traumatic testicular dislocation in the driver. We consider traumatic testicular dislocation as one of the important findings of fuel tank injuries in motorcycle accidents.

The stability of organophosphorus insecticides in fresh blood

We investigated the stability of 14 organophosphorus insecticides: dichlorvos, fenitrothion, cyanophos, malathion, phenthoate, methidathion, dimethoate, thiometon, isoxathion, diazinon, trichlorfon, EPN, acephate and sulprofos, in fresh blood. The organophosphorus compounds, except for sulprofos, decomposed over time at 37 degrees C, with varying decomposition speed for each compound. Methyl phosphate types (dichlorvos) decomposed most rapidly, followed by methyl thiophosphate types (fenitrothion and cyanophos) and methyl dithiophosphate types (methidathion, dimethoate and thiometon). Methyl thiophosphate types decomposed faster than ethyl thiophosphate types (isoxathion and diazinon). Of the five methyl dithiophosphate type insecticides (malathion, phenthoate, methidathion, dimethoate and thiometon), the compounds with a carboxylic ester bond (malathion and phenthoate) decomposed faster than the others. Compounds left standing at 37 degrees C decomposed faster than those left standing at 4 degrees C. Temperature has a great effect on the decomposition of organophosphorus insecticides in blood. However, the order of the decomposition speeds of each compound was approximately the same at different temperatures. In cases of suspected organophosphate poisoning, it should be considered that the blood concentration of the compound might decrease during the postmortem interval.

An Autopsy Case of Heart Rupture From a Scooter Accident With 3 Riders

A 15-year-old male died of cardiac rupture due to blunt chest trauma from a traffic accident involving a low-speed scooter carrying 3 people and a head-on collision with a tree. The victim was sitting on the footrest of the scooter. It was concluded that the victim was compressed between the handlebar of the scooter and the other 2 passengers, causing cardiac ruptures via bidirectional compression and intravascular hydrostatic pressure. The victim may have served as a cushion for the other 2 passengers, who were not thrown from the scooter and sustained only minor injuries.

Morules in endometrial carcinoma and benign endometrial lesions differ from squamous differentiation tissue and are not infected with human papillomavirus

BACKGROUND

Squamous differentiation/squamous metaplasia is often associated with endometrial adenocarcinoma and benign lesions, such as endometrial hyperplasia and chronic endometritis. Morules have distinct histological characteristics, and are referred to as squamous metaplasia or squamoid metaplasia.

AIM

To focus on the histological characteristics of morules and clarify the difference between morules and squamous differentiation.

MATERIALS/METHODS

Twenty endometrioid carcinomas with morules or squamous differentiation, five adenosquamous carcinomas, and eight non-carcinomatous endometrial lesions with morules were investigated. Numerous antibodies for epithelial membrane antigen (EMA), involucrin, cytokeratins, neuropeptides, and oncofetal antigens were used for immunohistochemistry. In situ hybridisation and polymerase chain reaction were used to detect human papillomavirus (HPV).

RESULTS

The morules observed were uniform cell clusters, with no squamous differentiation. They were immunonegative for epithelial antigens including involucrin, EMA, and cytokeratins, but were positive for neurone specific enolase. A few morules were immunopositive for acetylcholine esterase, and one case was positive for somatostatin; neither oncofetal nor proliferative cell markers, including blood group A, B, and AB, or other neuropeptides were demonstrated in the morules. HPV DNA was not found in either the morules in the carcinomas or in the benign lesions. However, true squamous differentiation tissue in four endometrioid carcinomas and two adenosquamous carcinomas was HPV positive using in situ hybridisation.

CONCLUSION

Morules are histologically distinct from squamous metaplasia/squamous differentiation tissue. Morules are thought to be neuroectodermal-like cell clusters, and are not infected with HPV. In contrast, some of the true squamous differentiation tissue was associated with HPV infection.

Kinetics of Trypanosoma cruzi infection in guinea-pigs, with special reference to the involvement of epidermal Langerhans' cells in the induction of immunity

Several studies have confirmed that epidermal Langerhans' cells (LC) play a central role in the induction of skin-related immunological events. In order to assess the role of LC in Chagas' disease, guinea-pigs were infected intradermally with Trypanosoma cruzi, sacrificed at different time-points, and their tissues were processed for routine histology, electron microscopy and immunohistochemistry. Parasitaemia was observed earliest at day 6 p.i. with 2 peaks at days 9 and 28, and disappeared on day 56 p.i. Parasite-specific serum IgG and IgM were first detected on day 12 p.i. The level of IgG gradually increased by day 84 p.i. All the infected guinea-pigs showed significant alterations in the distribution and morphology of epidermal LC during parasitacmia. The number of LC had significantly decreased in the epidermis by day 3 p.i., only returning to normal levels by day 56 p.i., although the number of LC in the underlying dermis increased concomitantly. Parasites were carried to the regional lymph node, where clustering of parasite-laden dendritic cells (DC) with lymphocytes was seen by electron microscopy. This evidence suggests that LC might be involved in antigen presentation in Chagas' disease.

Survival of destrobilated adults of Taenia crassiceps in T-cell-depleted Mongolian gerbils

In Mongolian gerbils (Meriones unguiculatus), prednisolone treatment induces the survival of strobilated Taenia crassiceps to sexual maturity followed by fecal release of gravid proglottides. The mechanism underlying the effects of prednisolone has not been elucidated in this taeniid/rodent model. Using a novel murine monoclonal antibody specific to a cell-surface determinant of gerbil T-cells (HUSM-M.g.15 of IgG2b isotype) for in vivo depletion of the cells, we examined the T-cell dependence of the following two phenomena: (1) elimination of strobilated T. crassiceps from the intestine of naive gerbils, and (2) depressed egg formation by the cestode in prednisolone-treated gerbils. In T-cell-depleted gerbils, only destrobilated adults were recovered from the intestine, although the recovery rate was comparable with that observed in prednisolone-treated animals. Egg formation by the cestode in T-cell-depleted, prednisone-treated gerbils did not differ from that seen in gerbils treated with prednisolone alone. We conclude that one of main effects of prednisolone can be ascribed to the suppression of T-cell functions that work to eliminate strobilated T. crassiceps from gerbils.

Two Taenia species found in Japan, with new distribution record of Taenia polyacantha Leuckart, 1856 (Cestoda: Taeniidae)

In an epidemiological survey for Echinococcus multilocularis in rodents and insectivores from the northernmost part of the central mainland of Japan (Honshu), two taeniid species, Taenia crassiceps and Taenia polyacantha, were found in Microtus montebelli and Apodemus argenteus, respectively. The latter is the first record of distribution in Japan, and the former is the second after its first recovery from the central part of Japan. Although we have found neither larval nor strobilar stage of E. multilocularis there, discovery of these taeniid species, having overlapping global distribution with E. multilocularis in red foxes Vulpes vulpes as well as multiple occurrences of hydatid patients having no history of visits to the endemic areas shows the possibility that the life-cycle of E. multilocularis might be maintained at least in the northernmost part of Honshu.

Helminth fauna of carnivores distributed in north-western Tohoku, Japan, with special reference to Mesocestoides paucitesticulus and Brachylaima tokudai

In the winter of 1998-1999, we collected parasitological data from 54 wild carnivores in the north-western part of Tohoku region, Japan. These consisted of 38 martens (Martes melampus melampus), 14 raccoon dogs (Nyctereutes procyonoides viverrinus) and 2 foxes (Vulpes vulpes japonica). Collected helminth parasites were 11 nematode, 10 trematode, 3 cestode, and a single acanthocephalan species, including 5 hitherto unknown species for this research area or the mainland of Japan (Honshu). Mesocestoides paucitesticulus was for the first time recorded from martens as well as from carnivores distributed in Honshu. Brachylaima tokudai originally recorded from Urotrichus talpoides in the central part of Honshu was for the first time found from a raccoon dog.

Parasitological survey on wild carnivora in north-western Tohoku, Japan

In the winter of 1997-1998, we collected parasitological data from 60 wild carnivora in the north-western part of Tohoku region, Japan. These included 7 foxes (Vulpes vulpes japonica), 20 raccoon dogs (Nyctereutes procyonoides viverrinus), 29 martens (Martes melampus melampus), 3 weasels (two Mustela sibirica itatsi and one M. nivalis namiyei), and one Japanese badger (Meles meles anakuma). Roundworms (Toxocara canis in foxes and Toxocara tanuki in raccoon dogs), hookworms (Ancylostoma kusimaense and Arthrostoma miyazakiense) and Molineus sp. in the small intestine were the most prevalent in foxes and raccoon dogs. In martens, Aonchotheca putorii in the stomach, Concinnum ten in the pancreatic duct, Molineus sp. and Euryhelmis costaricensis in the small intestine were the most prevalent. Collected parasites include some new helminth species for this region or Japan; the strobilar stage of Taenia polyacantha from foxes, Pygidliopsis summa from a raccoon dog, Eucoleus aerophilus, A. putorii, and Soholiphyme baturini from martens.