Dirty diving. Sudden death of a SCUBA diver in a water treatment facility.

We report a case of a sudden death in a SCUBA diver working at a water treatment facility. The victim, an employee of the facility with a specialty in electronics, was a sport diver not qualified in commercial diving. While attempting to clean sludge from a blocked drain 25 ft under water, the diver was suddenly pinned against the drain valve when the sludge plug was broken up. We review the mechanics of the incident and the actual cause of death, asphyxia, as opposed to drowning. We believe this to be the first reported case of traumatic (pressure) asphyxia in a SCUBA diver.     

Nitrogen narcosis and alcohol consumption--a scuba diving fatality

Nitrogen narcosis can cause death among experienced scuba divers. Nitrogen under pressure affects the brain by acting as an anesthetic agent. Furthermore, the consumption of ethanol along with diving will cause the symptoms of nitrogen narcosis to occur at depths less than 30 m. Our case deals with an experienced diver who drank alcoholic beverages before diving and developed symptoms of nitrogen narcosis at a shallow depth. These two conditions contributed to his death by drowning.     

Fatal air embolism in diving. A morphologic study

Two cases of barotrauma as a result of excess pulmonary pressure with subsequent air embolism are reported. Both cases involved serious diving safety errors. The morphology of this type of barotrauma is described, with particular reference to the etiology of the phenomena involved. Some specific points regarding the autopsy procedure in connection with such diving accidents are discussed.     

Virtopsy-postmortem multislice computed tomography (MSCT) and magnetic resonance imaging (MRI) in a fatal scuba diving incident

The body of a 44-year-old scuba diver was examined using postmortem multislice computed tomography (MSCT) and magnetic resonance imaging (MRI), and findings were verified by subsequent autopsy. The goal was to find out whether the important pathomorphological findings for the reconstruction of events and the identification of cause and manner of death could be identified using modem digital cross-sectioning techniques. The findings of a massive vital decompression with pulmonary barotrauma and lethal gas embolism were identified in the radiological images. MSCT and MRI were superior to autopsy in the demonstration of the extent and distribution of gas accumulation in intraparenchymal blood vessels of internal organs as well as in areas of the body inaccessible by standard autopsy.     

Suicidal Nitrogen Inhalation by use of Scuba Full‐Face Diving Mask

A 29‐year‐old man was found dead lying on the bed in a hotel room in a famous Slovak mountain resort. He had a full‐face diving mask on his face, connected through a diving breath regulator to a valve of an industrial (nondiving) high‐pressure tank containing pure 100% nitrogen. The breath regulator (open‐circuit type) used allowed inhalation of nitrogen without addition of open air, and the full‐face diving mask assured aspiration of the gas even during the time of unconsciousness. At autopsy, we found the typical signs of suffocation. Toxicological analysis revealed 94.7% content of nitrogen in alveolar air. Following the completion of the police investigation, the manner of death was classified as a suicide. Within the medico‐legal literature, there has been only one similar case of suicidal nitrogen inhalation described (1).     

Dermal absorption of kerosene components in rats and the influence of its amount and area of exposure

The influences of amount and area of dermal exposure to kerosene upon the levels of kerosene components in biological samples were examined in vivo and in vitro. Thirty-two rats were randomly divided into four groups and exposed to kerosene through the abdominal skin for 2h. The amounts (soaked in cotton) and area of kerosene exposed were 1 ml/4 cm(2) in Group I, 4 ml/4 cm(2) in Group II, 4 ml/16 cm(2) in Group III and 16 ml/64 cm(2) in Group IV. Before, then 5, 10, 20, 30, 45, 60, 90 and 120 min after exposure, 0.5 ml of blood was collected. Solid tissue samples, including the exposed skin area, were harvested at 120 min. Kerosene components were analyzed by gas chromatography/mass spectrometry. Trimethylbenzens (TMBs) that are easily absorbed kerosene components, appeared at 5-20 min. The time course changes in TMB levels in blood were significantly different between Groups I and II or Groups I and III, and almost identical between Groups II and III. Similar trends were observed in tissue samples at 120 min. High concentrations of aliphatic hydrocarbons (AHCs) were detected in the exposed skin and the AHC levels were dependent on the amount of kerosene exposed per unit area. These results suggest that (1) dermal absorption of kerosene occurs soon after dermal exposure started, (2) absorption of TMBs is influenced by the total amount of kerosene rather than area of exposure, and (3) AHCs remaining in the skin at significant levels are influenced by the amount of kerosene per unit area exposed.     

Microbiota Composition and Pulmonary Surfactant Protein Expression as Markers of Death by Drowning

Pathological diagnosis of drowning remains a challenge for forensic science, because of a lack of pathognomonic findings. We analyzed microbiota and surfactant protein in the lungs for a novel diagnosis of drowning. All rats were divided into drowning, postmortem submersion, and control groups. The water, lungs, closed organs (kidney and liver), and cardiac blood in rats were assayed by targeting 16S ribosomal RNA of Miseq sequencing. Lung samples were analyzed by immunohistochemical staining for surfactant protein A. The closed organs and cardiac blood of drowned group have a lot of aquatic microbes, which have not been detected in postmortem submersion group. Furthermore, intra‐alveolar granular staining of surfactant protein A (SP‐A) was severely observed in the drowned group than the postmortem submersion and control groups. The findings suggested that the presence of aquatic microbiota in the closed organs and increased expression of SP‐A could be markers for a diagnosis of drowning.     

Plasmatic levels of atrial natriuretic peptide (ANP) in drowning. A pilot study

Bodies found in water may cause problems for forensic pathologists who have to differentiate drowning from postmortem immersion or fresh from salt water drowning. The exact physiopathology of drowning is still controversial and complementary tests can not exactly establish the exact cause of death if macroscopic findings at autopsy are not conclusive. We have employed atrial natriuretic peptide (ANP) as a marker in an experimental series of fresh and salt water drowning, comparing their results with a non-drowned control series. There are differences between the plasma basal levels of the control series (79 pg/ml) and the levels in animals drowned in fresh water (358 pg/ml, P less than 0.001) and between control and rabbits drowned in salt water (190 pg/ml, P less than 0.001). According to these values, there are also differences between fresh and salt water drowned animals (P less than 0.001). We propose this peptide as a new marker in cases of drowning, with the ability to differentiate drowning from postmortem immersion and fresh from salt water drowning.     

Potential Forensic Application of Receptor for Advanced Glycation End Products (RAGE) as a Novel Biomarker for Estimating Postmortem Interval

Studies which estimate the postmortem interval (PMI) based on diatoms or bacterial communities have been well‐conducted. However, predicting the PMI based on microorganisms has limited accuracy. The objective of this study was to discover specific biomarkers for estimating the PMI for drowning. The in vivo experimental model consisted of rats classified into nine groups (seven drowned groups from Day 1 to Day 7 and two control groups). Their lung tissues were analyzed for the receptor for advanced glycation end products (RAGE) mRNA expression determined by qRT‐PCR. RAGE protein levels were determined by Western blotting and immunohistochemical (IHC) staining. RAGE mRNA and protein levels gradually degraded over time. Immunostaining analysis revealed that RAGE in the Day 1 sample was significantly higher than that in the Day 6 or Day 7 samples. These results indicate that RAGE in drowned lungs could be a potential biomarker for the determination of the PMI after drowning.     

Experimental study on postmortem formation of carbon monoxide

Rats were drowned and kept immersed for 1 month in either boiled city water, or boiled or unboiled fresh water collected from a river. A small amount of carbon monoxide (CO) formed after death and a low carboxyhemoglobin (HbCO) saturation was found in blood and thoracic cavity fluid of the animals immersed in boiled city water and in boiled fresh water. A considerable amount of CO and a high HbCO saturation was observed in blood and thoracic cavity fluid in two out of three rats immersed in unboiled fresh water at 4-6 degrees C, and in one out of three at 6-16 degrees C. It is suggested that microorganisms in the water, in which the rats were drowned and kept immersed, and low temperatures of around 5 degrees C during storage, played an important role in the postmortem formation of carbon monoxide.     

Fatal bilateral pneumothoraces after electroacupuncture treatment: A case report and literature review

Acupuncture is practiced as a complementary medicine worldwide. Although it is considered a safe practice, pneumothorax is one of its most common serious complications. However, there have been few reports of deaths due to pneumothorax after acupuncture treatment, especially focused on electroacupuncture. We report an autopsy case of a man in his 60s who went into cardiopulmonary arrest and died immediately after receiving electroacupuncture. Postmortem computed tomography (PMCT) showed bilateral pneumothoraces, as well as the presence of numerous gold threads embedded subcutaneously. An autopsy revealed two ecchymoses in the right thoracic cavity and a pinhole injury on the lower lobe of the right lung, suggesting that the needles had penetrated the lung. There were marked emphysematous changes in the lung, suggesting that rupture of bullae might also have contributed to bilateral pneumothoraces and fatal outcome. The acupuncture needles may have been drawn deeper into the body than at the time of insertion due to electrical pulses and muscle contraction, indicating the need for careful determination of treatment indications and technical safety measures, such as fail-safe mechanisms. This is the first case report of fatal bilateral pneumothoraces after electroacupuncture reported in the English literature. This case sheds light on the safety of electroacupuncture and the need for special care when administering it to patients with pulmonary disease who may be at a higher risk of pneumothorax. This is also the first report of three-dimensional reconstructed PMCT images showing the whole-body distribution of embedded gold acupuncture threads, which is unusual.     

Comparison between Temperature Gradient Gel Electrophoresis of Bacterial 16S rDNA and Diatom Test for Diagnosis of Drowning

When a body is discovered in water, it is difficult to conclude whether the cause of death was drowning, even today. Although diatom testing by the digestive method is classical, we hypothesized that aquatic bacteria, as well as diatoms, might be detected in drowned bodies, and conducted temperature gradient gel electrophoresis (TGGE)‐targeting 16S rDNA. DNA was extracted from the site water, and from heart blood and liver samples from 27 bodies concluded as drowning deaths by autopsy and subjected to TGGE after amplification of 16S rDNA by polymerase chain reaction. We observed whether the feature point of each 16S rDNA from the site water and blood or liver samples matched. Considerably higher correspondence was observed in drowned bodies, and the rate was higher than that achieved with the digestive method. Moreover, TGGE is safer than the digestive method. Our study suggests that this method can aid diagnosis of drowning.     

Diagnostic ability of D-dimer in the establishment of the vitality of wounds

The potential of skin measurements of D-dimer (DD), a specific derivative of crosslinked fibrin, for the diagnosis of the vital origin of wounds was investigated in 67 human vital skin wounds and homolateral control pieces of skin from 53 autopsies performed at the Institute of Legal Medicine of Coimbra (Portugal) during 1992. Our results demonstrate that DD levels for the incised vital skin wounds (n = 50) were much higher on average than their controls (P < 0.01) which were actually incised injuries produced postmortem at the autopsy. We did not find any statistical difference in average DD levels among the remaining injuries (seven abrasions and ten contusions) in comparison to their respective controls. DD may be used, with certain limitations, as a marker of the vitality of incised wounds. The authors believe this is the first time this marker has been applied in forensic pathology. It is an example of an easy and quick application technique, with the added advantage of low cost.     

Radiography of perforating centerfire rifle wounds of the trunk

All deaths resulting from perforating centerfire rifle wounds of the chest and abdomen, investigated by the Office of the Chief Medical Examiner for the Province of Alberta from 1988 to 1995. were reviewed retrospectively to determine whether the radiographic distribution of bullet fragments in such cases is a useful predictor of bullet trajectory. Study cases were limited to single gunshot wounds without surgical intervention or intermediate targets, and for which adequate radiography was available. Three pathologists individually viewed the radiographs on two separate occasions; wound locations were provided for the second viewing (Group 2). Differences in opinion regarding direction of fire were resolved by consensus review. A trauma radiologist independently made two sets of interpretations in the same way. Comparisons of these groups of interpretations were made with the actual bullet direction determined at autopsy. Of 21 cases included in the study, only three (14.3%) did not require consensus resolution in either group. Accuracy of pathologists' interpretation improved from 38.1% (8/21) to 76.2% (16/21) with provision of wound locations (p = 0.012). The radiologist achieved similar improvement, from 28.6% (6/21) to 47.6% (10/21). The rate of agreement between radiologist and pathologists increased from 42.9% (9/21) to 61.9% (13/21) between Groups 1 and 2. Both the pathologists and radiologist interpreted several cases the same way in both groups; of those cases interpreted differently, the second interpretation was occasionally incorrect after correct interpretation in Group 1. We conclude that bullet direction for perforating centerfire rifle wounds cannot be accurately determined from postmortem radiographs. When wound location is known, the ability to predict bullet direction improves but is still subject to error, including a lack of consistency between observers.     

溺死尸体器官硅藻检出率季节性差异

目的 研究溺水死亡者肺、肝、肾、骨髓等器官淡水硅藻检出率可能存在的季节性差异,为法医学解决水中尸体死因鉴定提供技术帮助与科学证据.方法 收集2009～2011年1、4、7、10月沈阳市浑河中溺死尸体每月(组)各5例;45只家兔分相应月份生前、死后入水组及对照组,分别于当月发现水中尸体后第2天入水,取人及兔肺、肝、肾、股骨骨髓及现场水样备检,应用酶消化法检测各组器官中硅藻数量、种属并与现场水样比对.结果 各组溺死尸体肺中均检出多量硅藻且种属与现场水样一致,春、秋及冬季溺死尸体肝、肾中仅可检出少量体积较小的小环藻等中心纲硅藻,夏季肝、肾及骨髓中均未检出硅藻;各组溺死家兔肺中均检出少量小环藻等中心纲硅藻,肝、肾及骨髓中未检出硅藻.结论 硅藻种群的季节性变化及不同种群硅藻体积的差异可能造成肝、肾等大循环器官中硅藻检出率的季节性差异;仅肺中检出硅藻,肝、肾中硅藻检验结果阴性并不能排除溺死可能.     

Primary intimal sarcoma of the pulmonary artery misdiagnosed as pulmonary thromboembolism: A case confirmed at medicolegal autopsy

Misdiagnosed PAS confirmed at medicolegal autopsy Pulmonary artery sarcoma (PAS) is a rare disease and usually indistinguishable from acute or chronic thromboembolic disease of the pulmonary arteries. We present a case of pulmonary artery sarcoma in a 54‐year‐old male, who was clinically misdiagnosed as pulmonary thromboembolism. The patient died of disease; however, the actual diagnosis of PAS was made after a medicolegal autopsy. PAS can be a diagnostic challenge for both clinicians and pathologists. In an autopsy case with a clinical suspicion of pulmonary thromboembolism, if there is an abnormal gross appearance in the pulmonary artery, the forensic pathologist should have a high index of suspicion of PAS, which should be ruled out by a histopathologic examination.     

Right ventricular damage due to pulmonary embolism: examination of the number of infiltrating macrophages

To investigate the pathological changes in the heart induced by pulmonary embolism, 20 autopsy cases of pulmonary embolism and 10 control cases of acute death from traumatic injury were examined. Adding to the routine hematoxylin-eosin (HE) staining, immunostaining with CD68 pan-macrophage marker was performed on the specimens obtained from both right and left ventricular walls. The number of macrophages was counted semi-quantitatively in 100 random high-power fields (HPF). Although typical pathological findings of myocardial infarction was not observed in any of the cases, 16 of the 20 pulmonary embolism cases showed an increase in the number of macrophages, mainly in the right ventricular wall. Four cases showed massive macrophage infiltration in the entire right ventricular wall. It is speculated that ischemia due to pulmonary embolism may be connected to its pathogenesis.     

Uncertainty of determining mode of death in medicolegal material without autopsy — A systematic autopsy study

Systematic autopsy was performed in 807 medicolegal deaths where the police had not requested autopsy. In all cases both the cause of death and the mode of death had been reported at the medicolegal external examination. The autopsy revealed differences in the mode of death in about 4% of all cases. This was due in particular to the problems associated with distinguishing presumed natural deaths from accidents and suicide. The cases of “concealed” suicide were found in particular among the higher age groups. However, no characteristic relationship was found between the proportion of differing modes of death and the age groups. All cases of homicide were recognized at the medicolegal external examination.Malignant disease that had not been diagnosed previously was found in about 4% of the cases, the reason being the large proportion of elderly subjects in the material. Syphilitic aortitis that had not been previously diagnosed was demonstrated in about 1% of all cases, and pulmonary tuberculosis that had not been previously diagnosed was demonstrated in 0.7% of the cases.The conclusion is that the results provide no support for replacing the medicolegal autopsy by medicolegal external examination alone, but rather suggest that the proportion of medicolegal autopsies should be increased.     

Determination of ABO blood groups by radioimmunoassay using 125I-protein A

Since the crystallizable fragment (Fc) portion of the immunoglobulin G (IgG) molecule is the binding site of Protein A, a radioimmunoassay procedure using 125I-Protein A was developed for identification of the ABO blood groups. The isotope level bound to Group A, B, or AB red cells decreased with the dilution of anti-A or -B, respectively. After sensitization by anti-A plus B in Group O serum, the isotope bindings were observed in Groups A, B, and AB cells, while no significant radioactive count appeared in Group O cells. Furthermore, there was little significant isotope binding in both Group A and B red cells sensitized by the serum from Group A or B blood containing mainly IgM anti-A or -B. A radioimmunoassay using 125I-Protein A is an excellent method for identifying ABO blood groups.     

Scanning electron microscope study of the lung in drowning

The authors describe the results obtained using the scanning electron microscope (SEM) to study drowned lungs and control lungs. Results are compared with a previous study carried out using laboratory animals. The results from both studies are analogous, in the absence of chronic pulmonary emphysema. The diagnosis of chronic pulmonary emphysema is simple with the SEM even when dealing with autoptic material obtained 24 to 48 h after death, but the diagnosis of drowning becomes difficult in lungs with chronic emphysema.