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Du Y, Xiang Q, Niu Y, Liu L, Liu J, Su Q, Li Z, Shi H, Xu Q, Wang H, Zhao J, Liu C. Diatoms pass through the gastrointestinal barrier and lead to false-positive: an animal experiment. Forensic Sci Med Pathol 2024; 20:351-359. [PMID: 37378810 DOI: 10.1007/s12024-023-00593-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/08/2023] [Indexed: 06/29/2023]
Abstract
The diatom test has been used by forensic pathologist as standard for drowning, but the occurrence of false-positive results (presence of diatoms found in the tissues of subjects who died from causes other than drowning) draws criticism regarding the specificity of the test. Diatoms within food or water can be ingested through the gastrointestinal tract. However, the mechanisms of how the diatoms reach distant organs such as the lung, liver, and kidney have not been studied. In this article, we simulated the process of diatoms entering the gastrointestinal tract using gastric lavage on experimental rabbits. Diatoms are detected in lymph from a lymphatic vessel at the root of the mesentery, portal vein blood, aortic blood, lung, liver, and kidney samples in the gavage group. Of diatoms, 76.24% were the centric diatom, 99.86% of diatoms have a maximum size of less than 50 µm, and most of diatoms concentrate in the lung. Our study provided the evidence supporting the theory that the diatoms could pass through the gastrointestinal barrier and reach the rabbits' other internal organs. The diatoms could reach internal organs through the portal vein and lymphatic vessel at the root of the mesentery. This provides us new insight into our understanding of false-positive diatom test in forensic pathology.
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Affiliation(s)
- Yukun Du
- Guangzhou Key Laboratory of Forensic Multi-Omics for Precision Identification, School of Forensic Medicine, Southern Medical University, Shaitai Road South 1023-1063, Baiyun District, Guangzhou, 510515, China
| | - Qingqing Xiang
- School of Forensic Medicine, Kunming Medical University, Chenggong District, Chunrong Road West 1168, Kunming, 650500, China
| | - Yong Niu
- Section of Forensic Sciences, Criminal Investigation Department, Ministry of Public Security, Dongcheng District, Chang' an Avenue 14, Beijing, 100741, China
| | - Lu Liu
- Faculty of Forensic Medicine, Zhongshan School of Medicine, Sun Yat-Sen University & Guangdong Province Translational Forensic Medicine Engineering Technology Research Center, Yuexiu District, Zhongshan 2Nd Road 74, Guangzhou, 510275, People's Republic of China
| | - Jingjian Liu
- Department of Anatomy, North Sichuan Medical College, Nanchong, 637000, China
| | - Qin Su
- Faculty of Forensic Medicine, Zhongshan School of Medicine, Sun Yat-Sen University & Guangdong Province Translational Forensic Medicine Engineering Technology Research Center, Yuexiu District, Zhongshan 2Nd Road 74, Guangzhou, 510275, People's Republic of China
| | - Zhigang Li
- Guangzhou Forensic Science Institute & Key Laboratory of Forensic Pathology, Ministry of Public Security, Baiyun District, Baiyun Avenue 1708, Guangzhou, 510442, People's Republic of China
| | - He Shi
- Guangzhou Forensic Science Institute & Key Laboratory of Forensic Pathology, Ministry of Public Security, Baiyun District, Baiyun Avenue 1708, Guangzhou, 510442, People's Republic of China
| | - Quyi Xu
- Guangzhou Forensic Science Institute & Key Laboratory of Forensic Pathology, Ministry of Public Security, Baiyun District, Baiyun Avenue 1708, Guangzhou, 510442, People's Republic of China
| | - Huijun Wang
- Guangzhou Key Laboratory of Forensic Multi-Omics for Precision Identification, School of Forensic Medicine, Southern Medical University, Shaitai Road South 1023-1063, Baiyun District, Guangzhou, 510515, China.
| | - Jian Zhao
- Faculty of Forensic Medicine, Zhongshan School of Medicine, Sun Yat-Sen University & Guangdong Province Translational Forensic Medicine Engineering Technology Research Center, Yuexiu District, Zhongshan 2Nd Road 74, Guangzhou, 510275, People's Republic of China.
- Guangzhou Forensic Science Institute & Key Laboratory of Forensic Pathology, Ministry of Public Security, Baiyun District, Baiyun Avenue 1708, Guangzhou, 510442, People's Republic of China.
| | - Chao Liu
- Guangzhou Key Laboratory of Forensic Multi-Omics for Precision Identification, School of Forensic Medicine, Southern Medical University, Shaitai Road South 1023-1063, Baiyun District, Guangzhou, 510515, China.
- Faculty of Forensic Medicine, Zhongshan School of Medicine, Sun Yat-Sen University & Guangdong Province Translational Forensic Medicine Engineering Technology Research Center, Yuexiu District, Zhongshan 2Nd Road 74, Guangzhou, 510275, People's Republic of China.
- Guangzhou Forensic Science Institute & Key Laboratory of Forensic Pathology, Ministry of Public Security, Baiyun District, Baiyun Avenue 1708, Guangzhou, 510442, People's Republic of China.
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Poulain C, Mathieu O, Gouetta V, Baccino É, Peyron PA. Influence of the toxicological status on the diagnosis of fatal drowning. Int J Legal Med 2023; 137:1471-1479. [PMID: 37433906 PMCID: PMC10421782 DOI: 10.1007/s00414-023-03057-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Accepted: 06/27/2023] [Indexed: 07/13/2023]
Abstract
Drowning is the leading cause of death by accident of everyday life in people under 25 years of age. Xenobiotics are frequently involved in drowning cases but their influence on the diagnosis of fatal drowning has not been studied so far. This preliminary study aimed to assess the influence of an alcohol and/or a drug intoxication on the autopsy signs of drowning, and on the results of diatom analyses in drowning deaths. Twenty-eight autopsy cases of drowning including 19 freshwater drownings, 6 seawater drownings, and 3 brackish water drownings were prospectively included. Toxicological and diatom tests were performed in each case. The influence of alcohol and other xenobiotics on drowning signs and diatom analyses was assessed separately then in combination through a global toxicological participation score (GTPS). Diatom analyses showed positive results in lung tissue in every case. No significant association was found between the degree of intoxication and the diatom concentration in the organs, even after considering freshwater drowning cases only. The vast majority of the traditional autopsy signs of drowning were not significantly affected by the individual toxicological status either, with the exception of lung weight which tended to raise in case of intoxication, probably due to the pulmonary edema and congestion increase. Further research on larger autopsy samples is needed to confirm the results of this exploratory study.
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Affiliation(s)
- Clément Poulain
- Department of Forensic Medicine, University Hospital of Montpellier, Montpellier, France.
| | - Olivier Mathieu
- Department of Medical Pharmacology and Toxicology, University Hospital of Montpellier, Montpellier, France
| | - Valérie Gouetta
- SNPS- Laboratoire de Police Scientifique de Toulouse, Toulouse, France
| | - Éric Baccino
- Department of Forensic Medicine, University Hospital of Montpellier, Montpellier, France
- Montpellier Criminal Law and Forensic Sciences research team (EDPFM, UR-UM212), Univ. Montpellier, Montpellier, France
| | - Pierre-Antoine Peyron
- Department of Forensic Medicine, University Hospital of Montpellier, Montpellier, France
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Hagen D, Pittner S, Zhao J, Obermayer A, Stoiber W, Steinbacher P, Monticelli FC, Gotsmy W. Validation and optimization of the diatom L/D ratio as a diagnostic marker for drowning. Int J Legal Med 2023; 137:939-948. [PMID: 36869250 PMCID: PMC10085902 DOI: 10.1007/s00414-023-02970-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Accepted: 02/08/2023] [Indexed: 03/05/2023]
Abstract
If a dead body is discovered in water, it nearly always raises the question about the cause of death, often associated with the persistent problem to differentiate between a drowning incident and post-mortem immersion. In numerous cases, a reliable confirmation of death by drowning is often only possible by a combination of diagnoses obtained from autopsy and additional investigations. As to the latter, the use of diatoms has been suggested (and debated) since decades. Based on the consideration that diatoms are present in almost every natural waterbody and are unavoidably incorporated when water is inhaled, their presence in the lung and other tissues can provide evidence of drowning. However, the traditional diatom test methods are still subject of controversial discussion and suspected of erroneous outcome, predominantly through contamination. A promising alternative to minimize the risk of erroneous outcome seems to be disclosed by the recently suggested MD-VF-Auto SEM technique. Especially the establishment of a new diagnostic marker (L/D ratio), which represents the factorial proportion between the diatom concentration in lung tissue and the drowning medium, allows for clearer distinction of drowning and post-mortal immersion and is largely robust to contamination. However, this highly elaborated technique requires specific devices which are frequently unavailable. We therefore developed a modified method of SEM-based diatom testing to enable the use on more routinely available equipment. Process steps such as digestion, filtration, and image acquisition were thoroughly broken down, optimized, and ultimately validated in five confirmed drowning cases. Taking certain limitations into consideration, L/D ratio analysis provided promising results, even in cases of advanced decomposition. We conclude that our modified protocol indeed opens a way for a broader use of the method in forensic drowning investigation.
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Affiliation(s)
- Dominik Hagen
- Department of Ecology and Evolution, Paris-Lodron University of Salzburg, Salzburg, Austria
| | - Stefan Pittner
- Department of Forensic Medicine and Forensic Psychiatry, Paris-Lodron University of Salzburg, Salzburg, Austria
| | - Jian Zhao
- Guangzhou Forensic Science Institute & Key Laboratory of Forensic Pathology, Ministry of Public Security, Guangzhou, China
| | - Astrid Obermayer
- Department of Ecology and Evolution, Paris-Lodron University of Salzburg, Salzburg, Austria
| | - Walter Stoiber
- Department of Ecology and Evolution, Paris-Lodron University of Salzburg, Salzburg, Austria
| | - Peter Steinbacher
- Department of Ecology and Evolution, Paris-Lodron University of Salzburg, Salzburg, Austria
| | - Fabio C Monticelli
- Department of Forensic Medicine and Forensic Psychiatry, Paris-Lodron University of Salzburg, Salzburg, Austria
| | - Walther Gotsmy
- Department of Forensic Medicine and Forensic Psychiatry, Paris-Lodron University of Salzburg, Salzburg, Austria.
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Sonoda A, Kakizaki E, Shinkawa N, Matsuda H, Yukawa N. Conventional diatom testing using strong acid: (II) Number and types of diatoms detected in closed organs and lungs of 80 autopsy cases using only new Kjeldahl flasks. Forensic Sci Int 2022; 341:111510. [DOI: 10.1016/j.forsciint.2022.111510] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Revised: 10/08/2022] [Accepted: 10/30/2022] [Indexed: 11/05/2022]
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Kakizaki E, Shinkawa N, Sonoda A, Yukawa N. Conventional diatom testing using strong acid: Notable false-positive results caused by an underestimated contamination source (blind spot). Forensic Sci Int 2021; 330:111131. [PMID: 34891083 DOI: 10.1016/j.forsciint.2021.111131] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2021] [Revised: 09/26/2021] [Accepted: 11/27/2021] [Indexed: 11/04/2022]
Abstract
Low rates of diatom positivity in the closed organs of drowning victims present challenges for diatom testing. High positivity rates in closed organs of non-drowning victims also raise an important issue. These contradictory findings were common in diatom testing studies undertaken during the 1960-80 s, but the reasons remained unclear. In the present study, we identified one of the most important factors associated with false-positive results in diatom testing using strong acid. One to 290 false-positive diatoms were found in reused Kjeldahl flasks that were thoroughly washed after the first diatom testing and kept free of tissue before the second testing. False-positive results occurred in 11 of 20 cases when more than approximately 10,000 diatoms were present in digested tissue or water samples. Reused flasks were found to contain many common diatoms (<30 µm), including Cocconeis, Cymbella, Diatoma, Gomphonema, Navicula, and Nitzschia, in agreement with reports of diatoms identified in closed organs. Surprisingly, such false-positive results occurred even at the sixth diatom testing using the same flasks kept free of tissues in each analysis. In contrast, no diatoms were detected in any reagent or associated with other glassware. Thus, reuse of Kjeldahl flasks can readily cause false-positive results that cannot be completely prevented by cleaning the flasks using alkali detergents, as evidenced by detection of diatoms even after six tests. We assume that diatoms causing false-positive results are partially melted by heating and fixed onto the flask's inner surface glass, as the diatom frustule consists primarily of SiO2, similar to glass. Adherent diatoms are then released from the glass by re-heating at the next diatom testing. These results also suggest that the number of diatoms remaining in a flask can increase steadily as a result of repeated reuse for analysis of lung or water samples. In contrast, in analyses using only new flasks, only one or two diatoms were found in 4 of 20 kidney, 2 of 12 liver, and 2 of 8 blood samples from 20 drowning victims. It is difficult to determine whether such diatoms are actually carried via the blood circulation, as contamination with a few diatoms can occur during autopsy procedures and diatom testing. In conclusion, only new (unused) Kjeldahl flasks should be used for diatom testing with strong acid digestion. Moreover, these data suggest that the number and frequency of diatoms present in closed organs of drowning victims may be much lower than previously thought.
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Affiliation(s)
- Eiji Kakizaki
- Division of Legal Medicine, Department of Social Medicine, Faculty of Medicine, University of Miyazaki, 5200 Kihara, Kiyotake-cho, Miyazaki 889-1692, Japan.
| | - Norihiro Shinkawa
- Division of Legal Medicine, Department of Social Medicine, Faculty of Medicine, University of Miyazaki, 5200 Kihara, Kiyotake-cho, Miyazaki 889-1692, Japan
| | - Ai Sonoda
- Division of Legal Medicine, Department of Social Medicine, Faculty of Medicine, University of Miyazaki, 5200 Kihara, Kiyotake-cho, Miyazaki 889-1692, Japan
| | - Nobuhiro Yukawa
- Division of Legal Medicine, Department of Social Medicine, Faculty of Medicine, University of Miyazaki, 5200 Kihara, Kiyotake-cho, Miyazaki 889-1692, Japan.
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Tsuneya S, Nakajima M, Makino Y, Torimitsu S, Yamaguchi R, Iwase H. A quantitative comparison between using sodium hypochlorite as a digestion method for the diatom test and the conventional method using fuming nitric acid. Forensic Sci Int 2021; 329:111086. [PMID: 34749279 DOI: 10.1016/j.forsciint.2021.111086] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Revised: 09/23/2021] [Accepted: 10/25/2021] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To determine the efficacy of using sodium hypochlorite (NaClO, Purelox) as a simple and rapid alternative digestion method for the diatom test through a quantitative comparison with the conventional method that uses fuming nitric acid (HNO3). MATERIALS AND METHODS In experiment 1, using 30 water samples, the NaClO and HNO3 methods were compared using paired t-test. In experiments 2 and 3, we included blank human lung plus 13 water samples and total of 32 drowned human lung samples, respectively, to compare the NaClO and HNO3 methods using paired t-test. The relationship between the concentration ratio and background factors was tested in experiment 3. Welch's t-test was used to determine differences in the ratio between the lung side and sex, whereas Pearson's correlation coefficient was used to determine the correlation between the ratio and either age or postmortem interval. The geometric mean of two counts was used for each specimen and all counts were logarithmically transformed to base 2 in the statistical analysis. RESULTS The NaClO method was completed within 80 min for any sample. In experiment 1, there was no significant difference between the NaClO and HNO3 methods using water samples (the mean of the ratios: 0.99, 95% confidence interval (95%CI: 0.89-1.10, P = 0.80). In experiment 2, the count of the NaClO method was lower than that of the HNO3 method using lung plus water samples (the mean of the ratios: 0.47, 95% CI: 0.35-0.65, P = 0.0002). In experiment 3, the concentration of the NaClO method was lower than that of the HNO3 method using drowned lung samples (the mean of the ratios: 0.28, 95% CI: 0.20-0.38, P < 0.0001). A weak correlation between the postmortem interval and the ratio of the two methods was observed (r = -0.58, P = 0.012), although no difference between lung sides or sexes were detected (P = 0.87 and P = 0.50, respectively) and no correlation occurred between age and the ratio (r = 0.15, P = 0.43). CONCLUSION Using NaClO as a simple and rapid digestion method for diatom testing of water samples would be an excellent alternative to conventional methods. Although the method's diatom detection rate for the lung samples was not optimal, it was still shown to be a feasible method.
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Affiliation(s)
- Shigeki Tsuneya
- Department of Forensic Medicine, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan; Department of Legal Medicine, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba 260-8670, Japan.
| | - Makoto Nakajima
- Department of Forensic Medicine, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Yohsuke Makino
- Department of Forensic Medicine, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan; Department of Legal Medicine, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba 260-8670, Japan
| | - Suguru Torimitsu
- Department of Forensic Medicine, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan; Department of Legal Medicine, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba 260-8670, Japan
| | - Rutsuko Yamaguchi
- Department of Forensic Medicine, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan; Department of Legal Medicine, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba 260-8670, Japan
| | - Hirotaro Iwase
- Department of Forensic Medicine, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan; Department of Legal Medicine, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba 260-8670, Japan
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Jiang L, Xiao C, Zhao J, Jiang T, Lin J, Xu Q, Liu C, Cai W. Development of 18S rRNA gene arrays for forensic detection of diatoms. Forensic Sci Int 2020; 317:110482. [PMID: 33142211 DOI: 10.1016/j.forsciint.2020.110482] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 07/27/2020] [Accepted: 08/30/2020] [Indexed: 02/07/2023]
Abstract
Diatom test is the most commonly used method to diagnose drowning in forensic laboratories. However, microscopic examination and identification of diatom frustules is time-consuming and requires taxonomic expertise. At present, the identification of drowning is still a challenge in forensic casework. In this study, we developed a novel diatom microarray based on the detection of specific 18S rRNA gene fragments of diatom species. The array covers 169 diatom species which were documented as commonly found in a wide range of fresh waters in China. Diatom arrays were prepared from species specific oligonucleotide probes targeting to variable regions of the 18S rRNA gene. We also developed an auxiliary sample preparation method for isolation of diatom DNA from tissues, which enabled detection of diatom species in real forensic samples as well as environmental waters. We applied the diatom arrays to analyze six drowned cases and eight environmental samples. The diatom arrays showed much better sensitivity and more consistent results than those of the conventional SEM methods. We discovered major discrepancies between results generated by the diatom arrays and the routinely used SEM based diatom tests. We verified the results of our diatom arrays by species specific PCR and Sanger sequencing and found that the currently used SEM diatom test method has a serious deficiency in sensitivity due to high loss rate of frustules in the sample preparation procedure. We anticipate that the application of diatom arrays will transform current forensic practice of diagnosing drowning deaths.
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Affiliation(s)
- Lin Jiang
- College of Biological Sciences and Technology, Fuzhou University, Fuzhou, 350108, China
| | - Cheng Xiao
- School of Forensic Medicine, Southern Medical University, Guangzhou, 510515, China; Guangzhou Forensic Science Institute, Guangdong Province Key Laboratory of Forensic Genetics, Guangzhou, 510030, China
| | - Jian Zhao
- Guangzhou Forensic Science Institute, Guangdong Province Key Laboratory of Forensic Genetics, Guangzhou, 510030, China
| | - Tao Jiang
- College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, 1037, China
| | - Jun Lin
- College of Biological Sciences and Technology, Fuzhou University, Fuzhou, 350108, China
| | - Quyi Xu
- Guangzhou Forensic Science Institute, Guangdong Province Key Laboratory of Forensic Genetics, Guangzhou, 510030, China
| | - Chao Liu
- School of Forensic Medicine, Southern Medical University, Guangzhou, 510515, China; Guangzhou Forensic Science Institute, Guangdong Province Key Laboratory of Forensic Genetics, Guangzhou, 510030, China
| | - Weiwen Cai
- College of Biological Sciences and Technology, Fuzhou University, Fuzhou, 350108, China.
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Piegari G, De Biase D, d'Aquino I, Prisco F, Fico R, Ilsami R, Pozzato N, Genovese A, Paciello O. Diagnosis of Drowning and the Value of the Diatom Test in Veterinary Forensic Pathology. Front Vet Sci 2019; 6:404. [PMID: 31799284 PMCID: PMC6868027 DOI: 10.3389/fvets.2019.00404] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Accepted: 10/29/2019] [Indexed: 12/14/2022] Open
Abstract
The detection of diatoms into the organs is considered an important “biological marker” for the diagnosis of drowning in human pathology, but it still has a high possibility for false positive results. The aims of this study were: (1) to evaluate the contribution of pathological examination in drowning cases and (2) to investigate the differences in the number and location of diatoms between animals who died in drowning and non-drowning conditions. For these purposes, 30 dead adult dogs were selected for the study and subdivided into five groups. The group A comprised six cadavers dead for drowning; the group B comprised six control animals; the groups C, D, and E comprised six animals dead for causes other than drowning and subsequently immersed in water for 24, 48, and 72 h, respectively. On each animal, a complete macroscopic and histological examination and diatom test were performed. Diatoms test and quantification were also performed on drowning mediums. Pathological findings of the animals in the group A showed pulmonary congestion, oedema, and hemorrages in the lung. However, similar injuries were also observed in control and experimentally submerged cadavers. In contrast, we observed a statistically differences between drowning animals and all experimentally submerged groups and control animals regarding diatom numbers recovered from organ tissue samples (p < 0.05). Therefore, these findings suggest that the number of diatoms may be used as a valid tool to differentiate animals who died in drowning and non-drowning conditions, even if the latter were found in an aquatic environment.
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Affiliation(s)
- Giuseppe Piegari
- Unit of Pathology, Department of Veterinary Medicine and Animal Production, University of Naples Federico II, Naples, Italy
| | - Davide De Biase
- Unit of Pathology, Department of Veterinary Medicine and Animal Production, University of Naples Federico II, Naples, Italy
| | - Ilaria d'Aquino
- Unit of Pathology, Department of Veterinary Medicine and Animal Production, University of Naples Federico II, Naples, Italy
| | - Francesco Prisco
- Unit of Pathology, Department of Veterinary Medicine and Animal Production, University of Naples Federico II, Naples, Italy
| | - Rosario Fico
- National Center for the Forensic Veterinary Medicine, Istituto Zooprofilattico Sperimentale delle Regioni Lazio e Toscana, Grosseto, Italy
| | - Raffaele Ilsami
- Unit of Pathology, Department of Veterinary Medicine and Animal Production, University of Naples Federico II, Naples, Italy
| | - Nicola Pozzato
- Verona Diagnostic Laboratory, Istituto Zooprofilattivo Sperimentale delle Venezie, Legnaro, Italy
| | - Angelo Genovese
- Department of Biology, University of Naples Federico II, Naples, Italy
| | - Orlando Paciello
- Unit of Pathology, Department of Veterinary Medicine and Animal Production, University of Naples Federico II, Naples, Italy
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9
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Analysis of false-positive results of diatom test in the diagnosis of drowning—would not be an impediment. Int J Legal Med 2019; 133:1819-1824. [DOI: 10.1007/s00414-019-02021-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Accepted: 02/06/2019] [Indexed: 10/27/2022]
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10
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Zhao J, Ma Y, Liu C, Wen J, Hu S, Shi H, Zhu L. A quantitative comparison analysis of diatoms in the lung tissues and the drowning medium as an indicator of drowning. J Forensic Leg Med 2016; 42:75-8. [DOI: 10.1016/j.jflm.2016.05.021] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2015] [Revised: 05/11/2016] [Accepted: 05/30/2016] [Indexed: 10/21/2022]
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11
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Kakizaki E, Yukawa N. Simple protocol for extracting diatoms from lung tissues of suspected drowning cases within 3 h: First practical application. Forensic Sci Int 2015; 251:179-85. [DOI: 10.1016/j.forsciint.2015.03.025] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2014] [Revised: 12/14/2014] [Accepted: 03/24/2015] [Indexed: 11/16/2022]
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12
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Lunetta P, Miettinen A, Spilling K, Sajantila A. False-positive diatom test: a real challenge? A post-mortem study using standardized protocols. Leg Med (Tokyo) 2013; 15:229-34. [PMID: 23701706 DOI: 10.1016/j.legalmed.2013.03.002] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2010] [Revised: 03/07/2013] [Accepted: 03/12/2013] [Indexed: 11/26/2022]
Abstract
The main criticism of the validity of the diatom test for the diagnosis of drowning is based on the potential ante- and post-mortem penetration of diatoms and the finding of diatoms in bodies of non-drowned human beings. However, qualitative and quantitative studies on diatoms in organs of the non-drowned have yielded both conflicting and contradictory results. In the present study, we have analysed under standardised methods the diatom content in several organs of 14 non-drowned human bodies. Overall, only 9 diatoms (6 entire, 3 fragmented) were disclosed in 6 of the 14 non-drowned bodies. Each of these 6 cadavers had only a single "positive" organ. Six diatoms were found in the bone marrow, 2 in the lung, and one in the pleural liquid. No diatoms were recovered from the brain, liver, kidney, or blood samples of any of these 14 bodies. Moreover, in five additional cadavers, whose lungs were injected, prior autopsy, with a 3.5L solution containing a bi-cellulate diatom culture (Thalassiosira baltica, Thalassiosira levanderi) via tracheostomy, a few diatoms appeared in the pleural cavity and in the blood from the left heart chamber, but none in any other internal organs investigated. The results of the presented study demonstrate that the issue of the false-positive diatom test should not be a logical impediment to the performance of the diatom method. However, strict and standardized protocols aimed at avoiding contamination during sample preparation must be used, appropriate separation values set and taxonomic analysis of all diatoms performed.
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Affiliation(s)
- Philippe Lunetta
- Department of Forensic Medicine, Hjelt Institute, University of Helsinki, Finland.
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13
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Munro R, Munro HMC. Some challenges in forensic veterinary pathology: a review. J Comp Pathol 2012; 149:57-73. [PMID: 23153727 DOI: 10.1016/j.jcpa.2012.10.001] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2012] [Revised: 09/08/2012] [Accepted: 10/06/2012] [Indexed: 10/27/2022]
Abstract
Forensic veterinary pathology is a diverse discipline that is in an early phase of its development. Common challenges include estimation of the age of skin wounds and bruises, the diagnosis of drowning and estimation of the time since death. However, many details of the pathological findings related to these various aspects await validation. The 'multispecies' nature of veterinary pathology, combined with the preponderance of published observations originating from animal experimentation, rather than casework, poses two challenges. Firstly, extrapolation of results between species may jeopardize the reliability (and credibility) of the forensic opinion. Secondly, experimental studies may not truly reflect the spectrum of changes seen in actual cases (e.g. extent of injuries, infection, age and health of victim). With regard to drowning, diagnosis based on post-mortem findings remains problematical. Methods for estimation of the time since death (also known as the post-mortem interval) continue to be a major focus of study, with fresh avenues such as post-mortem diagnostic imaging offering interesting possibilities.
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Affiliation(s)
- R Munro
- Royal Veterinary College, London, UK; Royal (Dick) School of Veterinary Studies, Edinburgh, UK.
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