Form variants of globular hyaline microthrombi. Light microscopy, immunohistochemical and scanning and transmission electron microscopy observations

Globular hyaline microthrombi are characterized by their diameter (2-30 micron), globular form, and positive PAS and PTAH reaction. They are a morphologic indicator of disturbed microcirculation and hemostasis, such as that occurring in shock. In two of our cases, we observed large globular hyaline microthrombi, some with central webbed degradation progressing to the formation of closed or open hollow globules. The electron microscopic findings were similar to those observed by other investigators in typical shock bodies. On the basis of the morphologic findings, the authors conclude that degradation phenomena start at the center of globular hyaline microthrombi and can progress to the surface where accelerated fibrinolysis is possible. The cellular elements that other investigators have described as a possible condensation center for fibrin precipitate proved to be structurally intact cells that are apparently located in niches of open hollow globules or in the center of circular hyaline microthrombi. The diagnostic relevance, vitality, and temporal classification are discussed.     

Pediatric drowning: a 20-year review of autopsied cases: II. Pathologic features

The pathologic findings in autopsies of drowning victims are nonspecific and vary from case to case. However, most reported pathologic series of drowning cases exclude children and do not take into consideration the unique circumstances surrounding bathtub drownings. In addition, the effect of resuscitation on the autopsy findings has not been studied in children. A retrospective review of autopsy records of non-bathtub drownings from a 20-year period (1984-2003) was performed and 63 cases were identified in 45 males and 18 females (age range 9 months to 17 years). The incidence of frothy exudate, pleural effusion, and increased lung weight was 43%, 36%, and 80%, respectively. The incidence of frothy exudate and the combination of all 3 factors was significantly higher in cases with no resuscitation compared with those cases with attempted resuscitation with or without delayed death. As the interval between the drowning episode and autopsy increased, the incidence of frothy exudate decreased significantly. There was no relationship between these findings and the age and sex of the decedent. Other clinical conditions or occult pathologic findings that may have contributed to death were found in 8 cases (13%). The findings highlight the need for thorough clinicopathologic correlation in cases of drowning to accurately interpret the pathologic findings.     

Presence of periorbital and conjunctival petechial hemorrhages in accidental pediatric drowning

The pathological findings of drowning are variable and non-specific. Petechial hemorrhages involving the periorbital region and the conjunctiva have been described in many causes of death, but are thought to be exceedingly uncommon in cases of drowning. However, such studies have not specifically addressed the pediatric population. The current study retrospectively examined 79 cases of accidental pediatric drowning for the presence of periorbital/conjunctival hemorrhages and analyzed factors that may have affected their presence. Ten victims had periorbital/conjunctival petechial hemorrhages (13%), with five having periorbital petechiae, three having conjunctival petechiae, and two having both periorbital and conjunctival petechiae. The age and gender of the victim, site of drowning, resuscitation history and the presence of other pathological findings were not significantly associated with the presence of periorbital/conjunctival petechiae. However, as the interval between the drowning episode and autopsy increased, the incidence of periorbital/conjunctival petechiae decreased (28% for <24h; 7% for >24h). The presence of periorbital/conjunctival hemorrhages in a significant proportion of pediatric drowning victims confirms that the pathologist must add this finding to the spectrum of changes seen in pediatric drowning.     

Death in bathtub revisited with molecular genetics: a victim with suicidal traits and a LQTS gene mutation

A 44-year-old woman with a medical history of mental disorders and previous suicidal behaviour was found in a bathtub and pronounced death few minutes later despite of resuscitation attempts. After police investigation and on the basis of autopsy findings, the death was classified as suicide drowning. Retrospective examination of clinical data revealed, a prolonged rate-corrected QT-interval (QTc: 468 ms) 3 months before death. Post-mortem (PM) DNA analysis disclosed KCNH2(FIN) mutation for the long-QT syndrome (LQTS). The value of PM molecular screening for LQTS is emphasised, especially for victims of putative drowning.     

Death in bathtub revisited with molecular genetics: a victim with suicidal traits and a LQTS gene mutation

A 44-year-old woman with a medical history of mental disorders and previous suicidal behaviour was found in a bathtub and pronounced death few minutes later despite of resuscitation attempts. After police investigation and on the basis of autopsy findings, the death was classified as suicide drowning. Retrospective examination of clinical data revealed, a prolonged rate-corrected QT-interval (QTc: 468 ms) 3 months before death. Post-mortem (PM) DNA analysis disclosed KCNH2_FIN mutation for the long-QT syndrome (LQTS). The value of PM molecular screening for LQTS is emphasised, especially for victims of putative drowning.     

Immunohistochemistry of pulmonary surfactant apoprotein A in forensic autopsy: reassessment in relation to the causes of death

To reassess the immunohistochemical distribution of pulmonary surfactant apoprotein A (SP-A) in relation to the causes of death, 282 forensic autopsy cases were reviewed. The most intense and dense granular immunostaining of intra-alveolar SP-A was observed in the hyaline membrane syndrome from various traumas, protracted death from drowning, and perinatal aspiration of amniotic fluid. Similar granular staining pattern was found in fatal poisoning by a muscle relaxant and organophosphate pesticides. An evident increase of intra-alveolar granular staining was noted in most fatalities from mechanical asphyxia and drowning, and some cases of fire death. SP-A staining was usually very weak or sparse in alcohol intoxication, poisoning by hypnotics and also carbon monoxide poisoning. These findings suggest that the amount of intra-alveolar granular SP-A staining may be a possible indicator of severity and duration of respiratory distress (agony) from peripheral (non-central nervous system) origin and alveolar damage.     

The forensic medical evaluation of the results of determining diatomaceous plankton in the diagnosis of drowning

Evaluation of demonstrative value of method based on diatom plankton determination as a diagnostical sign of death due to drowning was performed. Plankton was detected in the viscera in 37% of cases (as a whole 376 bodies of people who drowned in fresh water were examined). Plankton was detected in aspiration type of drowning and its mixed variant. In spastic and reflector types of drowning plankton wasn't detected. According to author's opinion this method is an objective diagnostical test to determine the cause of death of people when their bodies are found in water.     

Resuscitation measures and petechial thymus hemorrhages in sudden infant death

In 45 cases of sudden infant death syndrome (SIDS) in which unsuccessful attempts at resuscitation had been made and in 21 cases without attempted resuscitation, systematic histological investigations were carried out on the thymus. In these investigations, petechial hemorrhages were detected in 82% of the cases with attempted resuscitation and in 76% of the cases without attempted resuscitation. The histological distribution pattern of the petechial thymus hemorrhages did not differ notably between the two groups. The pattern of findings indicates that the hemorrhages had already developed during the death agony and that the typical histological distribution pattern with an increased occurrence of petechial in the cortical zone was altered by massive attempts at resuscitation in individual cases.     

Circumstances and macropathologic findings in 1590 consecutive cases of bodies found in water

The diagnosis of drowning relies primarily on critical examination of the subject's individual characteristics, circumstances, and postmortem macropathologic changes. In this retrospective study, based on 1590 consecutive cases of bodies found in water and undergoing autopsy at the Department of Forensic Medicine, University of Helsinki, from 1976 to 1998, the frequency of circumstantial data and macropathologic changes crucial for the diagnosis of drowning were determined. The fatal events were eyewitnessed in 403 cases (25.3%), and suicide notes were found in 83 cases (5.2%). External foam, frothy fluid in airways, and overlap of the anterior margins of lungs were found in 275 (17.3%), 739 (46.5%), and 669 (42.1%) of the cases, respectively, but no one of these changes, tested against dry-land controls, were specific for drowning. The association of external foam and overlap of the lung margins was exclusive of drowning but was observed in only 176 cases (11.1%). After cross-analysis, 964 (60.6%) of the cases had no circumstantial data or macromorphologic pathologic findings that allowed a definite diagnosis of drowning. The diagnostic problems in putative drowning cases, based on this study sample, have not been overrated. Studies to investigate and improve the reliability of complementary methods for the diagnosis of drowning are warranted.     

多发性软组织挫伤后对肺及其他脏器的影响

目的观察多发性软组织挫伤后短时间内死亡案例的脏器病理学改变。方法应用常规组织学及免疫组织化学染色技术进行光学显微镜检查。结果光镜检查见肺组织毛细血管扩张充血，白细胞集聚，肺组织散在片状出血、灶状坏死及透明膜形成；心脏间质血管扩张充血，点灶状纤维溶解；脑组织充血水肿，肝脾充血。免疫组化发现肺泡腔及部分血管内纤维蛋白染色阳性，部分脾脏血管内及肾髓质集合管中肌红蛋白染色阳性。结论本研究结果提示多发性软组织挫伤后短时间内死亡的死因为成人呼吸窘迫综合征（ARDS）合并多脏器功能衰竭。     

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.     

SEM/EDAX检测内脏异物元素成分诊断溺死

为探讨溺死诊断的依据和推断入水地点，用扫描电镜／X－射线谱仪（SEM／EDAX）检测19例溺死尸体及28只溺死兔的肺、肾、心、肝等组织异物颗粒及其元素成分和含量，并以陆地上死亡尸体14具及8只陆地上勒死兔（2只勒死后入水浸泡6天）作实验对照。结果发现，19例溺死尸体及28只溺死兔的肺边缘区呼吸性细支气管、肺泡管、肺泡囊及肺泡内均可见高能谱值的异物颗粒，其大小自数微米至数十微米不等，多为无定形异物颗粒或细小异物颗粒集落。其中元素成分为硅、铝、钙、铁、铬、钛、钼、铅、锡、铜、溴等，与入水地点溺液中所含元素成分相同；肾、心、肝组织异物颗粒检出率分别为77％、53％及47％，数量较少，颗粒较小，大小自1微米以下至十数微米。非溺死尸体及实验兔的肺、肾、心、肝组织未检出或偶尔检出异物颗粒，其元素成分多为铁、钙或硅等，可能是病理及生理性异物颗粒，如含铁血黄素、钙化灶等。用SEM／EDAX检测水中尸体组织中异物颗粒及其元素成分和含量，可以诊断溺死，推断入水区域，为明确案件性质和确定侦察范围提供科学依据。     

多发性软组织挫伤后成人呼吸窘迫综合征──组织学及免疫组织化学研究

本研究应用组织学Ｈ·Ｅ、Ｍａｌｌｏｒｙ、ＰＴＡＨ以及免疫组织化学染色方法对６例多发性软组织挫伤后成人呼吸窘迫综合征者肺组织改变进行了深入探讨。结果表明，所有外伤性呼吸窘迫综合征者肺组织均呈急性充血、出血及水肿改变，且免疫组织化学染色证明，水肿液中含有纤维蛋白（原）成份。在６例中２例可见肺组织局灶性出血坏死，３例有散在性血管内纤维蛋白柱形成及肺泡内透明膜形成。这些改变均属成人呼呼吸窘迫综合征的早期肺损伤。对多发软组织挫伤后呼吸窘迫综合征的形成机理进行阐述。     

The expert assessment of the sign of the presence of fluid in the basilar sinus in the diagnosis of drowning

Incidence of fluid presence (drowning medium) in basilar bone sinus of dead bodies found in water was studied according to pathogenetic type of drowning. Method of quantitative assessment of this sign in medicolegal evaluation of the cause of death when dead bodies were found in water is suggested.     

Selective culturing and genus-specific PCR detection for identification of Aeromonas in tissue samples to assist the medico-legal diagnosis of death by drowning

The detection of autochthonous aquatic bacteria in tissue samples from drowning cases is increasingly considered as an alternative approach to assist the medico-legal diagnosis of death by drowning. Bacteria belonging to the genus Aeromonas may be suitable candidates for this application as they are ubiquitous in natural aquatic environments but are generally not part of the human microbiota. The research aims of this study were (i) to develop a sensitive, specific and rapid screening and confirmation method for Aeromonas species in tissue samples and (ii) to evaluate aseptic sternal puncture as a post-mortem sample technique and bone marrow as an alternative matrix to provide evidence of death by drowning. The presence of Aeromonas in tissue samples was verified by cultivation using the selective media Ampicillin Dextrin Agar (ADA) and Ryan's Aeromonas Medium. The use of ADA medium was found most optimal for the sensitive, inexpensive and quick detection of aeromonads in human tissue samples. Positive culture plates were confirmed by harvesting all colonies for DNA extraction and subsequent PCR amplification using Aeromonas genus-specific primers. Aeromonads were detected in lung swab, blood and bone marrow of drowned bodies (n=3), but were negative in these three matrices for all negative controls (n=90) tested. Bone marrow proved to be a suitable alternative matrix and can be sampled post-mortem by an aseptic sternal puncture. In conclusion, this study confirms previous indications that aeromonads in cultures from blood of water bodies can be considered a potential marker for drowning. Given the fact that the number of immersed bodies (drowned and non-drowned) included in this study is statistically not significant, however, more tissue samples need to be investigated to confirm the validity of these methods to aid the diagnosis of death by wet drowning.     

Drowning without aspiration: is this an appropriate diagnosis?

It has been reported that 10-15% of drowning victims do not aspirate water. We have revisited the original studies quoted to reach this conclusion and find it is without foundation. Sudden cardiac standstill is known to occur on land and, therefore, may also occur when the victim is in water. In the absence of the common finding of significant pulmonary edema in the victim's respiratory system, to conclude his or her death was caused by "drowning without aspiration" is unwise. All causes of sudden death that might occur in which respiration may not take place should receive serious consideration when examining bodies with such findings that are found in water.     

A promising microbiological test for the diagnosis of drowning

A number of biological and chemical tests have been developed over the years to determine whether a person was drowned. This study focuses on the potential of a microbiological test for detecting common bacterial markers of water faecal pollution such as faecal coliforms (FC) and faecal streptococci (FS) as possible indicators of drowning. A promising previous study was carried out on central and peripheral blood samples of 42 drowned victims (20 cases in saltwater and 22 cases in freshwater) and 30 not-drowned bodies. To improve the accuracy of our previous results and also in order to investigate a possible cause of a false positive due to pulmonary passive diffusion and subsequently endogenous or exogenous bacterial invasion of the blood in the post-mortem interval (PMI), the FC and FS test was applied to bodies submerged in water but died from causes other than drowning. In the present study, blood samples collected from the left ventricle (LV), right ventricle (RV), femoral artery (FA) and, femoral vein (FV) of 10 drowned victims (5 cases in freshwater and 5 cases in seawater) and 3 not-drowned individuals with bodies submerged in water for a while after death have been analysed. Preliminary results are in agreement with other reports dealing with diatoms and marine bacteria that suggest to exclude the hypothesis of a passive penetration of sufficient quantities of drowning medium into circulation after death or during the agonal period. Based on our results there is also no evidence of a relevant dissemination of endogenous micro-flora from the gastrointestinal tract affecting the FS and FC test. There are still several other factors that could influence the applicability of post-mortem FS and FC cultures for the diagnosis of drowning and they need further investigations. The present article provides only a glimpse of the potential of the FS and FC test as bacteriological method for the diagnosis of drowning.     

Detection of diatoms in bone marrow (femur) of nondrowned (author's transl)

Diatoms in the bone marrow (femur) of 16 nondrowned bodies were detected by a modern method of ultrafiltration. The rate of diatoms were found to be in the same range as in cases of drowning. The results deny the proof of diatoms even in bone marrow to be useful any longer for the diagnosis of death from drowning.     

Pleural effusion in bodies recovered from water

Both in saltwater and freshwater drowning cases, a common autopsy sign is pleural effusion. However, the factors that determine the amount of pleural effusion have not been well established. An attempt was therefore made to correlate the amount of pleural fluid in bodies recovered from water with several parameters registered on the judicial files as well as autopsy findings from the years 1994-1998. The number of cases with pleural fluid increase was found to be very high in saltwater drowning (P<0.001). But, when the freshwater and saltwater drowning cases with pleural fluid increase were compared according to pleural fluid amount, no significant difference was detected (521+/-340 and 768+/-536 ml, respectively). Although there was a positive correlation between the decomposition degree and the fluid in the pleural cavity, a relative decrease was detected in the amount of effusion contrary to the expectations in cases of extreme decomposition. Pleural fluid amount provides significant data about the type of water and the cause of death in early postmortem interval. And there is a link between the time spent in water and the amount of pleural effusion. With the advance of the postmortem interval, decomposition level and the duration of immersion should be taken into account in differential diagnosis.     

Detection of marine and freshwater bacterioplankton in immersed victims: Post-mortem bacterial invasion does not readily occur

We previously applied our method of detecting marine or freshwater bacterioplankton (bacteria) in the blood of immersed victims as a marker of drowning. However, we did not confirm the absence of post-mortem bacterial invasion during immersion. Here we examined the nature of bacterioplankton in blood samples from 21 immersed and 4 non-immersed cadavers. We found only freshwater bacterioplankton in the blood of two victims that were retrieved from the sea or an estuary inhabited by marine bacterioplankton even though one victim was highly putrefied. The results of diatom testing suggested that these two victims had drowned in fresh or brackish water with low salinity and then flowed out to the estuary or the sea. Two others were submerged in water, but representative bacterioplankton were undetectable in their blood although one victim was highly putrefied. Autopsy findings and the results of diatom tests did not indicate that the cause of death was drowning. As in previous studies, we identified freshwater bacterioplankton in the blood of seven other victims that had drowned in freshwater, marine bacterioplankton in the blood of four victims that had drowned in seawater and none in four victims found on land that had died by means other than drowning. Bacterioplankton in the blood of drowned victims appears to reflect the type of water aspirated and blood does not become easily contaminated with bacteria post-mortem even in decomposed bodies.