The role of environmental factors in the causation of sudden death in infants: two cases of sudden unexpected death in two unrelated infants who were cared for by the same babysitter

We report two cases of sudden unexpected death in two unrelated African American female infants, 2 months and 4 months old. Both infants were attended to by the same babysitter in the same apartment and died 39 days apart in the same bed and in the same bedroom. The autopsy of the first infant revealed sudden unexplained death in an infant. Toxicologic analysis for carbon monoxide (CO) was not performed because it was not suspected. When the second infant died, investigation into the ambient air quality within the apartment revealed high levels of CO emanating from a poorly ventilated and defective hot water heater, which was located across a hallway from the bedroom where the two babies died. CO saturation levels in the postmortem blood samples of the two babies were elevated and were similar (13% and 14%). Nicotine and cotinine were not detected in the blood sample of the two infants. Cherry-red livor mortis was absent. Acute CO intoxication was determined to be the underlying cause of these two unexpected deaths. These two cases underscore the need to integrate ambient air analysis and postmortem CO analysis as routine components of the comprehensive death investigation of infants who die suddenly and unexpectedly.     

不同来源一氧化碳中毒死亡者血液中COHb含量分析

目的探索一氧化碳中毒存在的个体差异性,分析女性可能存在的抵御一氧化碳中毒的机制。方法收集207例不同来源的一氧化碳中毒死亡者血液,测量COHb含量,将案例按照不同的因素分类进行统计学分析。结果不同一氧化碳的来源对于死者的COHb浓度影响显著,而性别对于COHb浓度影响不显著,少年儿童和老年人有可能对COHb的抵御能力差于成年人。     

Fentanyl concentrations in 23 postmortem cases from the hennepin county medical examiner's office

The purpose of this study was to compare blood fentanyl concentrations in fentanyl-related deaths with fentanyl concentrations found incidentally at autopsy, as well as with fentanyl concentrations found in hospitalized patients receiving fentanyl. Between the years 1997 to 2005, 23 fentanyl-positive postmortem cases were identified. Nineteen of 23 (82.6%) cases were deemed to be drug overdoses. Fentanyl alone was responsible for 8 of the 19 (42.1%) overdose deaths. Mean and median fentanyl concentrations were 36 (SD 38) microg/L and 22 microg/L, respectively, range 5-120 microg/L. Seven of the cases were accidental, one undetermined. The remaining 11 of the 19 (57.9%) cases were mixed drug overdoses. Fentanyl concentrations in these cases were 31 (SD 46) microg/L, range 5-152 microg/L. All of the mixed drug overdoses were determined to be accidental. Four cases where fentanyl was considered an incidental postmortem finding were determined to be natural deaths. In hospitalized inpatients (n = 11) receiving fentanyl 2 of the patients receiving fentanyl for chronic pain for more than 3 months had concentrations of 8.5 microg/L and 9.9 microg/L. The other nine inpatient concentrations were less than 4 microg/L. In conclusion, blood fentanyl concentrations found in cases where fentanyl alone was determined to be the cause of death were similar to cases where fentanyl was part of a mixed drug overdose. There was also considerable overlap between fentanyl concentrations in fentanyl-related overdose deaths compared to hospitalized patients being treated for chronic pain. Fentanyl concentrations in postmortem cases must be interpreted in the context of the deceased's past medical history and autopsy findings.     

Usefulness of Systematic Histological Examination in Routine Forensic Autopsy*

Abstract: The forensic community does not agree on the need to perform histological examination at forensic autopsy. The aim of our study was to determine the usefulness of systematic standard histology in forensic autopsies. A prospective study was carried out on 428 autopsy cases for which standard histological examination was systematic. Mechanism of death not shown by gross anatomic findings was discovered by histology in about 40% of the cases. Cause of death was established by only histology in 8.4% of the cases. Microscopic findings affected the manner of death in 13% of the cases. Histology provided complementary information about prior medical condition of the deceased in about 49% of the cases. Traumatic lesions were better documented by histology in about 22% of the cases. According to the results of our study, systematic standard histology for the main organs should be used in routine forensic autopsies.     

大鼠血液中HbCO随吸入CO浓度和时间的变化

目的研究不同一氧化碳(carbon monoxide,CO)浓度下中毒大鼠的行为学特征、存活时间、碳氧血红蛋白(carboxyhemoglobin,HbCO)饱和度变化规律,为法医学实践中CO中毒死亡案件提供实验依据。方法将160只SD大鼠随机分为4组。自制染毒装置,使大鼠分别在CO浓度为1 250、3 750、6 250 mg/m~3及持续通入CO状态下染毒致死亡。观察不同CO浓度中毒大鼠的行为学特征,记录存活时间,采用分光光度法检测心血HbCO饱和度,并提取脑、心脏、肺、肝等器官进行组织病理学观察。结果 CO中毒大鼠的行为学特征表现为肢体瘫软、反应迟钝。随着CO浓度的升高,大鼠存活时间逐渐缩短,心血HbCO饱和度逐渐升高。在CO浓度为1 250 mg/m~3条件下,发现3例心血HbCO饱和度明显低于致死饱和度,其余各组未发现心血HbCO饱和度低于致死饱和度的情况。结论建立的不同浓度下CO中毒死亡动物模型,操作简单,重复性好,为进一步研究CO中毒及其他吸入性有毒气体的法医学研究奠定了基础。     

Trends in suicide by carbon monoxide inhalation in King County, Washington: 1996-2009

Carbon monoxide (CO) inhalation is one of the leading methods of suicide in the United States. A sharp increase in suicide by inhaling the CO produced from burning charcoal has been reported in parts of Asia; however, the incidence of this method has not been determined in a U.S. population. Thus, we determined trends of CO suicide in the ethnically diverse population of King County, Washington, U.S.A. During the period 1996-2009, we identified 158 cases of suicide by CO poisoning, with 125 because of automotive exhaust, 26 because of charcoal burning, and seven from other CO sources. While historical U.S. data indicate >99% of CO suicides in the United States occurring by automobile exhaust inhalation, in the most recent years analyzed, c. 40% of CO-related suicides in King County, Washington, were because of charcoal burning, indicating a possible shift in suicide trends that warrants further scrutiny in additional populations.     

Alligator attacks in southwest Florida

The American alligator inhabits bodies of fresh water in Florida and other southeastern states. Although attacks on pets are frequent, alligator attacks on humans are relatively rare because of the animal's natural fear of man. Because of the rarity of attacks on humans, the pathologic findings and pathophysiology of death in such cases have not been well characterized in the literature. We report three cases of fatal alligator attacks that occurred in southwest Florida, each with different pathologic findings and mechanisms of death. Although the cause of death in each case was attributed to the alligator attack, the mechanisms of death differed and included exsanguination because of amputation of an extremity, overwhelming sepsis, and drowning. These cases illustrate the varied pathophysiologies associated with deaths due to alligator attacks on humans and the features that distinguish alligator bites from those of other aquatic predators.     

一氧化碳中毒血分光光度定量分析法比较

目的比较7种一氧化碳中毒血样分光光度含量测定方法的特点及适用性。方法用空白血添加一氧化碳配制不同浓度的样品,采用双波长法、还原法（3种）、切线法和导数光谱法（2种）进行检测,对各种方法线性范围、重现性和操作中注意事项等内容进行考察,并用实际案件检材验证和比较。结果还原法一在30%~70%、还原法三在20%~100%,其他方法在20%~70%范围内,线性关系良好;样本浓度超过或低于50%,采用切线法有一定误差;导数法及还原法三因需要制备CO饱和样本,操作略微繁琐,但导数光谱法计算结果准确性好。结论几种方法均可用于一氧化碳中毒血的检测,实验结果可为方法的实际应用提供借鉴和帮助。     

Percentage of body recovered and its effect on identification rates and cause and manner of death determination

Anthropologists frequently encounter cases in which only partial human remains are recovered. This study reports how the percentage of the body recovered affects identification (ID) rates and cause and manner of death determination. A total of 773 cases involving anthropology consults were drawn from the New Mexico medical examiner's office (1974-2006). Results indicate a significant correlation between body percent recovered and ID rates, which ranged from 89% for complete bodies to 56% when less than half the body was present. Similar patterns were evident in cause/manner determination, which were the highest (83% and 79%, respectively) in complete bodies but declined to 40% when less than half the body was found. The absence of a skull also negatively impacted ID and ruling rates. Findings are compared with general autopsy ID rates (94-96%) and cause/manner determination rates (96-99%) as well as prior published rates for individual casework and mass death events.     

CT在法医病理学中的应用与展望

计算机断层扫描(CT)能够对不同密度的人体组织进行成像,在疾病和损伤的检验中具有重要的应用价值,随着CT技术的不断发展和逐步成熟,它可以对组织脏器进行容积再现、多层面重建、最大密度投影、表面遮盖显示等后处理,在肿瘤、血管畸形等疾病的诊断,骨折、关节异位、脏器破裂、出血等损伤的检验,枪弹、爆炸碎片、吸入物等体内异物的检验中具有重要的应用价值。目前已经有不少学者将其应用到相关研究领域当中。本文对近几年国内外应用CT技术进行法医病理学研究的情况进行综述,以便法医病理学研究者了解CT在法医病理学领域中的应用及研究现状,能够为今后的法医病理学科学研究和实践工作提供新的思路。     

死亡人体组织中rRNA亚基的稳定性及影响因素评价

目的探讨人尸体组织中rRNA亚基表达水平的稳定性及影响因素。方法选取3例成人、3例婴幼儿大脑皮质和脾组织,在尸检即刻、48、72、96、120、144、168、192、216、240h,采用实时荧光定量RT-PCR法检测5s、5.8s、18s、28s rRNA的表达水平。结果两个年龄组两种组织中4种rRNA亚基表达量相比较均显示有差异(P0.05)。同种组织比较:脑组织中两个年龄组最后一个时间点与第一时间点4种rRNA亚基的表达量均有差异(P0.05),其他各时间点与第一时间点无显著性差异(P0.05);脾组织中婴幼儿5s rRNA在最后一个时间点,其余3种rRNA亚基最后两个时间点与第一时间点比较有差异(P0.05);成人5s rRNA最后一个时间点,5.8s rRNA亚基最后两个时间与第一时间点比较差异(P0.05),其余两种亚基各时间点与第一时间点相比较均无差异(P0.05)。结论尸体组织中rRNA亚基表达稳定性好,适于作为晚期死亡时间推断的内参基因使用,但需注意指标、组织和年龄段差异性。     

Diesel fumes do kill: a case of fatal carbon monoxide poisoning directly attributed to diesel fuel exhaust with a 10-year retrospective case and literature review*

While it is known that diesel fuel combustion engines produce much lower concentrations of carbon monoxide (CO) than gasoline engines, these emissions could certainly generate lethal ambient concentrations given a sufficient amount of time in an enclosed space and under suitable environmental conditions. The authors report a case of CO poisoning which was initially referred for autopsy as a presumed natural death of a truck driver found in the secure cab of a running diesel tractor trailer truck. Completion of the preliminary investigation ascribed death to complications of ischemic heart disease (IHD), pending toxicological analysis that included quantification of CO. When the toxicology results showed lethal blood COHbg, the cause of death was re-certified as CO intoxication secondary to inhalation of (diesel) vehicular exhaust fumes. Because of the unique source of fatal CO intoxication in this case, the contributory IHD and the possible contaminants in the putrefied blood, a 10-year retrospective review was conducted on all nonfire related CO deaths autopsied (n = 94) at the Office of the Chief Medical Examiner in Louisville, KY from 1994 to 2003. For validation of the COHbg detection method used by the Kentucky Office of Forensic Toxicology (KYOFT), blood samples from these cases along with controls were submitted to three laboratories using various analytical methods yielding no statistically significant differences. Lastly, an extensive literature review produced no scientifically reported cases of fatal CO poisoning attributed to diesel fuel exhaust.     

Poisoning deaths in Central China (Hubei): A 10-year retrospective study of forensic autopsy cases

A retrospective study of autopsy cases was conducted at the Department of Forensic Medicine, Tongji Medical College (DFM-TMC), in Hubei, China to describe the characteristics of poisoning deaths from 1999 to 2008. A total of 212 poisoning deaths were investigated by DFM-TMC during the 10-year period. The poisoning deaths ranged from 17 cases in 1999 to 27 cases in 2008. Of the 212 cases, 82 deaths (38.7%) were from pesticides, 36 deaths (17.0%) from carbon monoxide, 34 deaths (16.0%) from drugs, 22 deaths (10.4%) from alcohol, 17 deaths (8.0%) from other chemicals, 15 deaths (7.1%) from poisonous plants and animals, and six deaths (2.8%) from heavy metals. Of the 82 pesticide poisoning deaths, 43 (52.4%) cases were caused by rodenticides, mainly tetramine (N = 39). The majority of poisoning deaths were accidents (63.7%), followed by suicides (25.9%) and homicides (3.8%). The manner of death could not be determined in 14 cases (6.6%).     

青壮年猝死综合征研究现状

青壮年猝死综合征(SMDS)一直是国内外医学界尤其是法医学领域研究的热点,近来对SMDS的发病特点及致病机制等都有广泛而深入的研究,但仍有部分关键问题尚未解决。本文通过文献复习并结合法医检案,分别从分子遗传学、免疫组织化学、冠状动脉结构或功能异常、自主神经调节作用等方面介绍SMDS的研究进展。     

不同环境条件下大鼠死后皮肤大体和组织学改变

目的研究观察大鼠在不同环境条件下死后不同时间其皮肤大体、组织学的改变,为推测较长的死后间隔时间建立实验动物依据。方法观察雌性SD大鼠在不同环境条件下的死后变化,并间隔一定死后时间取皮、染色和镜下观察。结果死后发生骨、软组织分离,A组约需35d,B组需13d。皮肤有形细胞成分和附属器完全分解破坏,A组约20d,B组7d。胶原纤维在A组死后40d（B组12d）仍有部分保留完整。结论环境温度差异是造成A、B两组发生死后改变时程不同的主要因素,利用皮肤大体、组织学改变可望较系统和准确的推测晚期死亡时间。     

Forensic anthropology and the most probable cause of death in cases of violations against international humanitarian law: an example from Bosnia and Herzegovina

This study presents the results of the analysis of at least 298 predominantly male individuals, between 15 and 75 years, who were recovered from an open cast mine in Bosnia-Herzegovina. Particular attention is paid to identifying the mechanisms of injury and determination of the most probable cause of death based on the assessment of lethal or lethal-if-untreated injuries recorded in the skeleton. It was calculated that at least 38.9% (155/398) of individuals sustained gunshot wounds (GSWs) (plus one shrapnel wound) and may have died as consequence of these injuries. Among individuals who died from GSWs, there were 142 males (91.60%), eight females (5.1%) and five cases that were (3.2%) undetermined. One male individual sustained shrapnel injuries. This study presents an example of the multidisciplinary approach to the effective forensic investigation of violation against International Humanitarian Law, as well as an example of how it is possible to obtain meaningful results to assist the needs of the prosecution in these kind of cases despite the large number of cases and technological constraints.     

Calliphora vicina (Diptera: Calliphoridae) collected from a human corpse above 3400 m in elevation

In the summer of 2005 an adult hiker was killed in a fall in Rocky Mountain National Park, Colorado (U.S.A.). His body was subsequently colonized by the blowfly Calliphora vicina (Diptera: Calliphoridae). The body was discovered 9 days later at an elevation of 3475 m (11,400 feet). This is the first report of C. vicina on a human corpse at this elevation in Colorado. This paper provides additional confirmation of this fly colonizing a human corpse at high elevations in Colorado.     

甲醛对一氧化碳中毒血检验干扰的研究

目的探讨甲醛对一氧化碳中毒血的检测是否产生干扰,提高一氧化碳中毒鉴定的可靠性。方法采用常用的血中一氧化碳或碳氧血红蛋白饱和度的检测方法对未加甲醛和加甲醛的血样分别进行实验研究。结果甲醛对加热法、氢氧化钠法、氯化钯法、分光光度法等检测方法均可产生不同程度的干扰。结论经福尔马林灌注或固定的检材不宜用于一氧化碳中毒血检测,否则可能导致错误的鉴定结论。     

Utility of immunoassay in drug screening in skeletal tissues: sampling considerations in detection of ketamine exposure in femoral bone and bone marrow following acute administration using ELISA

Detection of ketamine exposure in skeletal tissues by automated enzyme-linked immunosorbent assay (ELISA) and gas chromatography with electron capture detection (GC-ECD) is described. Rats (n = 18) received 0, 15, 30, or 75 mg/kg ketamine hydrochloride acutely (i.p.), and were euthanized within 15 min or 1 h. Ketamine was extracted from ground femoral bone by methanolic incubation followed by liquid-liquid extraction (LLE), while marrow was homogenized in alkaline solution, and then underwent LLE. Extracts were analyzed by ELISA, and subsequently by GC-ECD following derivatization with trifluoroacetic acid anhydride. The effect of tissue type (i.e., diaphyseal bone vs. epiphyseal bone vs. bone marrow) on the immunoassay response was examined through determination of binary classification test sensitivity (S) and measurement of the relative decrease in absorbance (%DA, drug-positive tissues vs. drug-free controls) in each tissue type. The %DA varied significantly between different tissues examined under a given dose condition, and generally decreased in the order marrow > epiphyseal bone > diaphyseal bone, at all dose levels examined. Measured S values for marrow, epiphyseal bone, and diaphyseal bone were 100%, 77%, and 23%, respectively (75 mg/kg dose). These results suggest that the type of skeletal tissue sampled and position sampled within a given bone (diaphyses vs. epiphyses) are important parameters in drug screening of skeletal tissues.