The thesis is an answer for debating question regarding of pathologic characteristics of drowning and proposes the DNA analysis for identification method. The description study concluded the valuable pathologic signs and characteristics for diagnosis. In this study, the DNA analysis was applied for victims identification.
MINISTRY OF MINISTRY OF HEALTH EDUCATION AND TRAINING HA NOI MEDICAL UNIVERSITY NGUYEN LE CAT ASSESSMENT THE FORENSICALLY HISTOPATHOLOGIC CHARACTERISTICS AND IDENTIFICATION METHOD OF DROWNING VICTIMS Specialized : Pathology and Forensic Medicine Code : 62720105 ABSTRACT OF THE THESIS FOR MEDICAL DOCTOR HA NOI - 2020 THE THESIS WAS COMPLETED IN HA NOI MEDICAL UNIVERSITY Scientific Supervisor: PhD Luu Sy Hung Associate Professor Dinh Gia Duc The first Reviewer: Associate Professor Nguyen Phuc Cuong The second Reviewer: PhD Nguyen Duc Nhu The third Reviewer: PhD Tran Ngoc Dung The Thesis approved by Council of scientist in Ha Noi Medical University At: Date: 2020 References theThesis in: Vietnam National Library Library of Ha Noi Medical University LIST OF PUBLICATIONS This Thesis is based on the following papers: Nguyen Le Cat (2013), Signs and injuries of drowning in forensic identification, Journal of Practical Medicine, 876 (7): 54-57 Nguyen Le Cat, Nguyen Van Hoa, Nguyen Tat Tho (2017), Notes when receiving preserved corps for identification in accidents and disasters, Journal of Military Pharmaco-Medicine, 323 (7-8): 9-11 Nguyen Le Cat, Nguyen Thi Ngoc Anh, Do Thi Xao Mai (2018), DNA analysis results in the victim identification of aircraft accidents at sea, Journal of Military PharmacoMedicine, 333 (11-12): 44-48 Nguyen Le Cat, Nguyen Thi Ngoc Anh, Do Thi Xao Mai, Luu Sy Hung (2019), Assess the results of drowning victim identification by DNA test in forensic examination, Journal of Military Pharmaco-Medicine, 335 (3-4): 54-58 INTRODUCTION Drowning is being asphyxiated caused by submersion of noses or mouth The mechanism is complicated and varied depending on the situation, not only the asphyxia in submersion It is believed as the first problem of public health, and early studied because of social valuation In evaluation of WHO, the proportion of drowning is 5.6/100.000 population, two third is accidental, 1/3 suicidal drowning, rarely homicidal drowning Most of victims are children or young people Vietnam is a tropical country, there are a large number of lakes and rivers, long beach which are potential for drowning, especially in hurricane season As others countries, the most common cause is occupational or daily activity Others are homicidal or suicidal cause In Military Institute of Forensic Medicine, the proportion of drowning is high However, there is no research of epidemiology, pathology and victims identification In forensic examination, there are some problems for solving: - Who is the victim? The cause of death? The cause of death is drowning or not? Which examination or test to confirm the drowning cause? - Could the patient be identified ? Which test for identification? In order to so, the forensic examiner has to fully collect the primary evidences, analysis the scene, and forensic results, in combination with proper identification method Therefore, the study “Assessment the forensically pathologic characteristics and identification method of drowning victims” aims to: Description of the pathologic signs and characteristics of drowning victims Application of DNA analysis in identification of drowning victims The need of the thesis The thesis is an answer for debating question regarding of pathologic characteristics of drowning and proposes the DNA analysis for identification method The description study concluded the valuable pathologic signs and characteristics for diagnosis In this study, the DNA analysis was applied for victims identification The contribution of the thesis Statistical description of general characteristics of drowning such as: conjunctivitis (100%), lividity pattern (74.6%), rigor mortis (89.4%), froth (66.4%), wrinkle skin (58.1%), exophthalmos (100%), flared mouth (78.8%), peeling skin (72%), fluid and foam in the airway (54.8%), pulmonary edema (88.5%), the foreign body in airway (35.5%), water in stomach (30.8%), the laceration of aveoli (88.5%), rupture RBC in vessels and organs (50%) Diatom test plays an important role in diagnosis confirmation and location of drowning The application of DNA analysis is an appropriate method to victims identification: there was 18.02% victims need to DNA analysis for identification, successful identification was 100% (31/31); from 1-4 postmortem days, most of victims were identified by the normal method (83.3%-84.2%); 85% victims was required the DNA analysis for identification from 5-9 days postmortem From 1-4 days postmortem, the nucleus analysis was used for every victim From 5-15 postmortem, the mitochondrial analysis was more preferred, After 15 days postmortem, most victims was identified by mitochondrial analysis The structure of the thesis The thesis includes 108 pages General description (02 pages), Conclusion (02 pages), and proposal (01 page) Four chapters : Chapter : General description (31 pages), Chapter : Objects and Methodology (13 pages), Chapter 3: Results (22 pages), Chapter 4: Discussion (37 pages) It also includes 26 tables, 04 images, 09 charts, 73 reference materials, study form and victims list, the image illustrates Chapter BACKGROUND 1.1 Definition and classification of drowning 1.1.1 Definition In 2002, the International Congress of Drowning defined drowning as : “The asphyxiated process caused by submersion in liquid” 1.1.2 Classification It is classified into two categories: intention and un-intention Intention: homicidal or suicidal, Un-intention: accident, or undefined cause 1.2 Statistical evidence of drowning 1.2.1 General statistics of drowning According to WHO, there are 372000 death caused by drowning each year; 42 death caused by drowning in average each hour Drowning is the top cause of death for 1-24 years old population 1.2.2 The co-factor of drowning 1.2.2.1 Age The most common is in 1-4 years old children, then 5-9 years old It is one of the most cause of death for 1-14 years old population in 48/85 countries 1.2.2.2 Gender Most of study showed that the proportion was doubled in male rather than female 1.2.2.3 Location In the low or average income countries, the scene of drowning is the place of daily activities In the other hand, in high income countries, the scene is in the recreation park 1.2.2.4 Time It depends on the victims and seasons 1.2.2.5 The causes In the international congress, the causes was classified as: Accidental (56.2%), suicidal (23.8%), homicidal (0.28%), unidentified (16.5%) 1.2.2.6 Others risk factors Alcohol, smoking, poorness, shortage of safety facility, climate, the treatment approach, rehealibitation are the others risk factors 1.3 The pathologic mechanism 1.3.1 The history of drowning knowledge It was firstly introduced in Greek AC by Galen At that time, it was supposed that the water filling in stomach and intestine causes the death The later studies showed that the water fills in the airway and lung causing death 1.3.2 The mechanism of drowning There are four main mechanisms: water inhalation, the filtration of water in blood stream, alveolus rupture and nervous reflex 1.3.2.1 Water inhalation a, Stage (1.5 minutes): Submersion victim, strungling to breath, water fills in the stomach, low blood pressure, low heart beat b, Stage (1 minute): Because of reflexion, victims drink and inhale a large amount flux of water, till the trachea and alveolus, tachycardia, the water bubles from nose to the water surface c, Stage (1-1.5 minutes): Epilepsy, coma, low BP, arrythmias, ventricular fibrillation, cardiac arrest 1.3.2.2 The water filtration in blood stream There are two situations: a) Drowning in fresh water: The dilution of blood causing the hypoosmolar natrium and chlorium causing the blood cells ruptures b) Drowning in salt water: Condensed blood No rupture of blood cells, the electrolyte equilibration is unchange 1.3.2.3 The alveolus rupture Water enter the alveolus causing dilation and rupture Hemorrhage in the lung parenchyma, other alveolus without water would be stressed causing emphysema 1.3.2.4 The nervous reflexion Beside the alveolus rupture, water in the airway causing inhibition of respiratory and cardiovascular centers located in the medullar leading to death 1.4 The forensic pathology of drowning 1.4.1 The external signs 1.4.1.1 The foam It is typical sign of drowning It is different with foam caused by pulmonary edema, this foam is more diluted and fragile 1.4.1.2 The rapid death in drowning Cold cadaver, the temperature is equal with enviroment in primary 8-24 hours, pale and wrinkle skin, eyes swelling 1.4.1.3 Signs of body soaked in water Skin spikes, cold corpses, body temperature decreased by the ambient temperature of the autopsy detected in 8-24h, skin of palms and feet pale, wrinkled, eye mucus bulging due to water absorption 1.4.1.4 The traumas and evidences before and post mortem a, Traumas and evidences before mortem: water jumping, epilepsy, trauma injuries b, Trauma and evidences post mortem: Caused by floating cadavers 1.4.1.5 The decomposition signs In the water, it is pale cadavers In the early of air exposure, the skin color change from green to black The cadavers will be decomposed rapidly, especially in summer 1.4.2 The internal signs 1.4.2.1 New cadavers a) Special signs: - The respiratory system: The trachea is fulfilled with the pink foam Swelling lungs, motley lung surface Foregin body in airway - The circulation system: Congestion organs, diluted blood, and red blood cells ruptures - The gastrointestinal system: Water in stomach and intestine Hepatomegaly, pale kidney, pale intestin, submucosal hemorrhage - Brain: Congesion and edema b) Others signs: Water infiltrates in the sinus of head and face Hemorrhage in the middle ear and mastoid bone Emphysema Soil, grass in the palm Parasites 1.4.2.2 Decomposed cadavers The importants signs are disappeared: deflated lungs, foam and water in trachea Water is in the shallow of chest The foreign body could appear in the airway 1.4.3 The signs of untypical drowning Inhibition reflexion (cardiac arrest, larynx spasm, dry drowning, death because of drowning complication) 1.4.4 The evolution of signs In general: Self water absorption, decomposition and self movement Floating time: depends on the water temperature and characteristics of cadavers 1.4.5 The characteristics of forensic organs pathology 1.4.5.1 Lungs Water and foreign bodies in the alveolus, hemorrhaging, alveolus dilation Micropathology could be suggession, thin alveolus wall, rupture of alveolus The gold diagnosis is the appearance of water foreign body in small bronchi and alveolus 1.4.5.2 Liver The dilation hepatic and portal veins are filled with blood and water The portal areas are dilated, swelling vessel wall, the parenchyma is filled with water and blood Congestion of organs 1.4.6 The change of biochemistry Imbalance serum electrolyte caused by water filtration 1.4.7 The biologic agents Diatoms test: In 1941, Incze proposed the diatoms test to define location of drowning 1.5 Some new studies of drowning In 2015, Hosahally J.S et al conclued that: in fresh water drowning victims, the intima of aorta root was darker In 2005, J.Blanco Pamoin et al showed that 21.58% victims had the rupture of gastric mucosa Milone A et al also showed that CT scanner could help to define the death before or after asphyxia 1.6 The forensic assessment of drowning 1.6.1 The methods It is much more exact if there is a combination of methods to examine the cadaver 1.6.2 DNA forensic examination The DNA identification of drowning is exact and efficient Especially in case of decomposed cadavers 1.6.3 DNA structure DNA is double chains created by two single nucleotids chain In DNA, there are a lots of genes in particular order The location of gene in chromosome is called locus In nuclear DNA, each locus has two allens, one from dad, the other from mom Mitochondrial DNA is completely maternally generated 1.6.4 The DNA analysis 1.6.4.1 The nuclear DNA Nuclear DNA analysis is based on the structure and genetic characteristics With this method, the individual could be well identified only by small sample 1.6.4.2 The mitochondrial DNA Beside nuclear, the DNA also exists inside the mitochondrial in the circle form, and maternal heredity Therefore the mitochondrial DNA analysis gave lots of success 1.6.4.3 The comparison in DNA analysis - Direct comparison: Between the victims DNA and the stored victims DNA - Indirect comparison: Between the victims DNA and the DNA of victims familial members 1.6.4.4 The comparison of nuclear and mitochondrial DNA - Nuclear DNA analysis: It is unstable in the nature enviroment It is easy, cheap and rapid analysis - Mitochondrial DNA analysis: Circle form, stable in nature enviroment It is more difficle, poorly exact, long time for analysis 10 3.1.2 Time of year Table 3.2 The months of the year Month Group 10 11 12 n 1-5 1 0 0 0 6-14 0 0 0 17 15-29 10 61 30-44 0 5 7 45 45 - 59 1 1 1 19 More 60 0 1 1 1 0 Undefine 2 2 0 17 Total 27 23 14 25 23 22 172 3.1.3 Time of forensic examination Table 3.3 Post mortem forensic examination st Day Day Day >15 Time Undefine day 2-4 5-9 10-15 days p 0.1 Total n 108 36 20 172 % 62.1 20.9 11.6 2.3 1.7 0.6 100 3.1.4 Place of death Table 3.4 Place of death Location River Lake Wellwater Sewer Pool Sea water Tank Flood Total n 69 53 24 172 % 40.1 30.8 5.2 14.0 4.7 0.6 2.9 1.7 100 11 Manner of death 3.1.5 Table 3.5 Manner of death Situation Accident Suicide Homicide Undefine Total n 119 12 40 172 % 69.2 7.0 0.6 23.2 100 3.1.6 Others characteristics • Occupation Table 3.6 Occupation Occupation Related Unrelated Undefine Total n 150 17 172 % 2.9 87.2 9.9 100 • Educational level of the victim Table 3.7 Educational level of the victim Educational Non Primary Secondary High level educated school school school Graduation Unof high Total define school n 30 87 20 11 17 172 % 4.1 17.4 50.6 11.6 6.4 9.9 100 • Ethnic Table 3.8 Ethnic distribution Ethnic Ethnic minority Ethnic major Undefine Total N 73 82 17 172 % 42.4 47.7 9.9 100 12 3.2 The external signs Table 3.9 Statistical of external signs Yes Signs No Undefine Total n % Froth 42 24.42 130 172 Lividity pattern 128 74.42 44 172 Conjunctivitis 123 71.51 41 Rigor mortis 137 79.65 35 172 Submersion skin 110 63.95 62 172 Flaring mouth 44 25.58 128 172 Occular change 47 27.32 125 172 Necrosis 52 30.23 120 172 Foreign bodies in palm 15 8.72 157 172 Decomposition 1.74 168 172 Trauma by the water flux 35 20.35 137 172 Trauma by the animal 4.07 165 172 172 3.2.1 Froth Table 3.10 Froth First day Day 2-4 Day 5-9 Yes 39 0 No 69 33 20 Total 108 36 20 Froth Day >15 Un10-15 days define Total p n % 42 24.42 130 75.58 0.001 172 100 13 3.2.2 Lividity pattern Table 3.11 Lividity pattern Lividity pattern Day Yes Day >15 Undefine 10-15 Days Total Day 2-4 Day 5-9 107 19 0 128 74.42 No 17 19 44 25.58 Total 108 36 20 172 100 p n % 0.001 3.2.3 Conjunvitis Table 3.12 Conjuncvitis Conjucnvitis Day Day Day 2-4 5-9 Day >15 10Undefine Days 15 Total n % Yes 89 20 10 1 123 71.51 No 19 14 49 28.49 Total 108 34 15 3 172 100 3.2.4 p 0.02 Rigor mortis Table 3.13 Rigor mortis Rigor Day Day mortis 2-4 Day 5-9 Day >15 Undefine 10-15 Days Total n % Yes 106 28 0 137 79.7 No 18 35 20.3 Total 108 36 20 172 100 3.2.5 p 0.001 Submersion skin Table 3.14 Submersion skin characteristics Submersion skin Day Day 2-4 Day Day >15 Un5-9 10-15 Days define Total n p % Slight change 58 0 0 62 36.05 0.001 Pale 49 0 58 33.72 Scale off 24 20 52 30.23 Total 108 36 20 172 100 14 3.2.6 Flaring mouth Table 3.15 The flaring mouth post mortem Flaring mouth Day Day 2-4 Day 5-9 21 19 Yes Total Day >15 Un10-15 days define p n % 44 25.58 0.001 No 108 15 1 128 74.42 Total 108 36 20 172 100 3.2.7 Occular change Table 3.16 Occular change post mortem Total Occular change Day Day 2-4 Less change 105 16 0 125 72.67 Exophthalmos 20 16 43 Deflated eye 0 1 2.33 Total 108 36 20 172 100 3.2.8 Day Day >15 Un5-9 10-15 Days define n % p 25 0.001 Decomposition post mortem Table 3.17 Decomposition post mortem Decomposition Day Day 2-4 Yes 24 20 No 107 12 0 Total 108 36 20 Total Day Day >15 Un5-9 10-15 days define n % 52 30.23 120 69.77 172 p 0.001 3.2.9 100 Foreign bodies in palms Table 3.18 Foreign bodies in palms Foreign bodies Day Day 2- Day 5-9 Day >15 Un10-15 Days define Total n % Yes 13 0 0 15 8.72 No 95 34 20 157 91.28 Total 108 36 20 172 100 p 0.49 15 3.2.10 Injuries caused by floating and animal Table 3.19 Injuries caused by floating and animal Injuries Front of body Back of body Total Chafing of shallow skin 20 26 Torning skin Making underwater animal - - p 0.54 3.3 Internal signs In the our research, there were 172 cases in which 48 cases only external examination, 20 cases with external examination and the tracheostomy, 104 cases examinated inside and outside of body 3.3.1 Signs and lesions in the trachea and bronchi Table 3.20 List of signs and lesions in the trachea and bronchi Characteristics Fluid, air bubbles Foreign object in airway, bronchi Decomposition Unknown Total n 68 44 11 124 % 54.8 35.5 0.8 8.9 100 3.3.2 Signs in the organ Table 3.21 Statistics of signs in the organ Yes No Unknown Total Signs p n % n % n % Pulmonary edema 92 88.5 7.7 8.8 104 Congestive of other organ 95 91.3 8.7 0 104 Water in stomach 85 81.7 16 15.4 2.9 104 Water in sphenoid sinus 8.6 0.9 94 90.5 104 0.001 16 3.3.2.1 Pulmonary lesions Table 3.22 Characteristics of pulmonary lesions Pulmonary lesions Paltauf sign Petechiae (Tardieu sign) Lung stretch and slice with more blood Lung bland and slices with little blood Unknown Yes 32 43 92 n 104 104 104 104 104 % 30.8 41.3 88.5 7.7 8.8 3.3.2.2 Congestive of organs Table 3.23 Characteristics of congestive in organs Congestive of organs Heart Liver Kidney Spleen Brain Yes 82 91 93 67 56 n 104 104 104 104 104 % 78.8 87.5 89.4 64.4 53.8 3.3.2.3 Objects in stomach Table 3.24 Characteristics of objects in stomach Objects in stomach Water Water and food Food None of food and water No information Total 3.3.3 n 32 45 16 104 % 30.8 43.2 7.7 15.4 2.9 100 Mixed lesions Table 3.25 Characteristics of mixed lesions Lesions n Injures of soft tissue Fracture Brain trauma Hanging trauma Cutting wist Hematoma around shoulder joint Breaking stomach Yes % 3.85 1.92 1.92 0.96 0.96 0 No n 100 102 102 103 103 104 Unknown % n % 96.15 0 98.08 0 98.08 0 99.04 0 99.04 0 104 100 100 0 Total p 104 104 104 104 0.001 104 104 104 17 3.4 Atypical drowning Table 3.26 List of atypical drownings Type Near-downing Dry-downing Drowning with heart and vessel disease n Total 104 104 104 % 7,7 1.9 3.5 Other test 3.5.1 Histopathology Table 3.27 Signs and lessions of histopathology Signs and lessions Foreign objects in the airway Alveolus rupture and oedema Breaking red blood cells Congestive in liver Congestive and bleeding in heart Congestive and oedema in brain Congestive and oedema in kidney 3.5.2 No n % 76 73.1 1.9 52 50 3.8 4.8 2.9 2.9 Unknown n % 7.7 10 9.6 0 5.8 18 17.3 45 43.3 30 28.8 Total p 104 104 104 104 0.001 104 104 104 Diatom test Table 3.28 Results of diatom test Categories of diatom Bacillary diatom Stellar diatom Polygonal diatom 3.5.3 Yes n % 20 19.2 92 88.5 52 50 79 76.0 81 77.9 56 53.8 71 68.3 Yes No Total 7 p 0.154 Other test Table 3.29 Results of other test Yes Test Alchohol in blood Narcotics in blood Toxic in organs No Positive n % 2.9 Negative n % 48 27.9 n % Total p 119 69.2 172 0.6 28 16.3 143 83.1 172 0.08 0 40 23.3 132 76.7 172 18 3.6 Identification of asphyxiated victims by DNA analysis technique 3.6.1 Distribution of victim identification based on indentified time Table 3.30 Distribution of victim identification based on indentified time Time The1st day Day 2-4 Day 5-9 Day 10-15 Over 15 dáy Unknown Total 3.6.2 Result of victim sampling Table 3.31 Result of victim sampling Time The first day Day 2-4 Day 5-9 Day 10-15 Over 15 days Unknown Total 3.6.3 Normal DNA No Number identification identification identification of p victim n % n % n % 108 91 84.2 1.9 15 13.9 36 30 83.3 11.1 5.6 20 15.0 17 85.0 0 0.001 0 100 0 0 100 0 0 100 0 172 124 72.1 31 18.0 17 9.9 Victim sampling Hair Tissue Tooth Bone 0 0 12 12 3 Number of victim 17 Blood 0 2 31 14 11 21 18 71 Total 10 43 Sampling results of relatives Table 3.32 Sampling results of relatives Time The first day Day 2-4 Day 5-9 Day 10-15 Over 15 days Unknown Total Number of victim 17 31 Sampling of relatives Number of relatives Blood Hair Mucosa Total 26 45 26 3 42 1 25 0 17 14 44 11 84 19 3.6.4 DNA extraction results of victim sampling Table 3.33 Mean of DNA level of extraction in victim sampling Time The first day Day 2-4 Day 5-10 Day 10-15 > 15 days Unknown Number Number of of Small victim corpses (ng/µl) 17 4 10 43 0.1721 0.1322 0.0944 0.0833 0.021 Mean of DNA level Large (ng/µl) Y (ng/µl) CT DI 0.1842 0.1288 0.0619 0.0612 0.01 0.1798 0.1211 0.0797 0.198 0.01 28.5 28.5 28.5 29.5 33 0.93 1.36 1.52 2.1 3.6.5 Result of identification by technique of DNA analysis Table 3.34 Result of identification by technique of DNA analysis Time The first day Day 2-4 Day 5-9 Day 10-15 Over 15 days Unknown Total Number of victim 17 31 Identification by the nucleus DNA n 16 0 23 % 100 100 94.1 25 0 74.2 Identification by mitochondrial DNA n % 0 0 5.9 75 100 100 25.8 p 0.001 Chapter DISCUSSIONS 4.1 General characteristics 4.1.1 Age and gender Age: It is an important risk factor In this study, Table 3.1 showed that the dominant drowning was from 15 to 29 years old (35.5%) It is different with others studies This difference could be caused by the social and epidemiology characteristics, and unrecorded of victims Gender: Male dominated 79.1%, female proportion was 20.9% This result is different with WHO index, however it fits in others studies in Vietnam, Katrina showed the ratio 3/1, L.Quan and P.Cummings in 2003 showed the ration 3.5/1 20 4.1.2 The frequence of drowning regarding the months of the year In this study, the victims concentrated in the second and third trimester (77.9%) In April, the frequence was highest (15.7%) The low frequence was from Oct to March It is the same result with L.Quan and P.Cummings studies: 50% victims was from May to August, Luis K Lee with 65% victims from July to September, Nguyen Thanh Uyen, Bui Quoc Thang with 43% from April to July 4.1.3 The time of forensic examination From Table 3.3, the most of patients was examined in the first day (62.1%), the low proportion patients was examined after 10 days (4%) In the othes studies, it has not been mentioned 4.1.4 Place of death In this study, the highest proportion was in the lake and stream (40.1%); then lake (30.8%), swimming pool (4.7%) This result respects the statistical one of UNICEF in Vietnam (river 59%, lake 29.2%); similar to Nguyen Hoang Thanh Uyen and Bui Quoc Thang studies (71% in lake) However it is different with Weinstein (beach 75%, swimming pool 22%), Richard in Australia (beach 8.3%, swimming pool 17.3%) 4.1.5 Manner of death Table 3.5 showed that 119.172 (69.2%) victims was the accident drowning, 12/172 7%) was suicidal drowning, only 1/172 (0.6%) was homicidal drowning; 40/172 (23.2%) undefined the situation This result fits in the report of Drowning international conference: accident 893/1590 (56.2%), suicidal drowning (23.8%), undefined drowning (16.5%), homicidal drowning (0.82%) This result also fits in other study in Thuong Hai China from 2000 to 2009 4.1.6 Others characteristics - Occupation: only 5/172 (2.9%) victims was related with watery occupation - The victims in secondary school was dominant (50.6%); then primary school (17.4%), high school (11.6%) It is similar with the result in China, Uganda, Bangla-Desh - Ethnic: There was no difference between ethnic minority and others 4.2 External signs 4.2.1 Foam In this study, 24.42 % victims had foam cone in the primary 1-4 days post mortem There was no victim with froth after days It is similar with others studies in China, Uganda, Bangla-Desh 21 4.2.2 Lividity pattern In this study, 74.2% victims had lividity pattern The first day was apprearant From 2-4 primary days, this proportion decreased to 19/36 victims (52.78%), and from the fifth day, only 1/27 victim had this sign This result is similar with Weinstein and Richard in Australia 4.2.3 Conjuctivitis In this study, 123/164 (75.51%) victims with conjuntivitis, predominantly from 2-4 primary days From fifth day, it disappeared This is similar with Sydney, Smith, Bajanowski et al 4.2.4 The submersion skin sign In this study, 58/108 victims had slight change of skin; 49/108 victims had wrinkle palm and sole skin, only one had peel off It is similar with Simonin result However it is earlier than the study result of M Durigon 4.2.5 Decomposition sign In this study, flaring mouth, exophthalamos, necrosis appreared from second day: 44/172 flaring mouth victims (25.58%)(Table 3.15); 43/172 exophthalmos victims (25%); 52/172 necrosis victims (30.23%) It is more rapid than European study 4.2.6 The foreign objects in palm In this study, 15/172 (8.72%) victims had the foreign objects in palm, these were in the first day of drowning The analysis of the foreign bodies and compare it to others scenes could help to identify the scene of drowning However, it is not available in Vietnam because of facility shortage 4.2.7 Floating trauma In this study, 26 victims had the floating trauma Among them, 20/26 victims had injuries in the posterior victims had the laceration injuries victims had injuries caused by the animal 4.2.8 Time of drowning In this study, the most common signs in the first two days was congestion, conjuncvitis (100%); rigor mortis (89.4%); wrinkle skin (58.1%) From the third to the tenth days: exophthalmos (100%); flaring mouth (78.8%); peeling skin (72%) After 10 days, there was only victims It is more rapid change in comparison with Celcandi and Durigon from second to third weeks 22 4.3 4.3.1 Internal signs Pulmonary edema and organs congestive Pulmonary edema was in 88.5% victims; Paltauf sign was in 30,8% victims; pulmonary tension and hemorrhage was in 88,5% victims; Tardieu sign was in 41,3% victims; 7.7% victims with loosen lung With other organs such as heart, liver, kidney; 95/104 (91.3%) had congestive, 9/104 (8.7%) without organ congestion It is similar to Bajanowski et al result 4.3.2 The foreign objects in airway In this study, 35.5% victims had the foreign objects in airway It is similar to Sydney, Smith, Bajanowski et al 4.3.3 Water and foreign objects in GI tract In this study, 32/104 victims had lots of water in stomach without food; 45/104 victims had food and water in stomach; 16/104 victims had neither water nor food in stomach It is different to Sydney Smith 4.3.4 Compromised injuries Most of victims had injuries before mortem; soft tissue 4.1%; fracture 1.7%; cranial trauma 2.25%; patient with hanging sign in the neck; victime with self cutting wirst 4.4 Atypical drowning After the concensus in The international drowning conference, the definition of near drowning, dry drowning and wet drowning are not appropriate However there were some relation to these definitions in this study, then it needs to discuss further 4.5 Additional test 4.5.1 Histo-Pathology test In this study, 104/172 victims was organs collected to pathology; 20/104 victims had the foreign bodies in airway; 92/104 (88.5%) victims had edema in pulmonary parenchyma; 52/104 victims had RBC rupture and exudation in alveolus; 81/104 victims had heart congestion; 79//104 victims had liver congestion; 71/104 victims had renal congestion The results was similar to Sydney Smith, Bajanowski 4.5.2 Diatom test In this study, victims was collected the organ and fluid to diatoms test The diatom is coincidence with the scene: 5/7 (71.4%) stripe diatoms; 1/7 (14.3%) star-shaped diatoms, 1/7 (14.3%) polygonal shaped diatoms It is similar to Ludes B et al, Auer et Mottonen, MuellerKerde 23 4.5.3 Others complimentary tests In this study, 5/53 victims had ethanol in the blood, 1/29 victim had phenobarbital, no one had toxic in the organ It is lower than the others studies 4.6 4.6 Indentification by DNA analysis 4.6.1 Sample collection In this study, there was 31 victims demanded for identification by DNA analysis There were 71 samples, depending on the decomposition of cadavers In order to compare, there were 84 samples from 45 familial members, the priority order was mother, father, brother and sister 4.6.2 The collection of DNA in cadavers It had been done by Quantifiler Trio DNA Quantification in Real Time PCR 7500 machine The concentration of DNA decreased according to time, then it was difficult to performe nuclear DNA identification, then it moved to mitochondrial DNA identification 4.6.3 The collection of DNA in familial members It was collected by chelex method The PCR result and DNA analysis showed 24 locus for male and 22 locus for female With mitochondrial DNA analysis, the HV1 and HV2 was fully analysed 4.6.4 DNA analysis Every sample collected from first to tenth days was available for STR analysis In mitochondrial DNA analysis, the teeth and bone was focused in HV1 and HV2 by particular chains It is sequenced in the ABI3500 machine, showed the good outcome 4.6.5 The outcome of identification DNA analysis identification is confidence and exact It gave 31/31 good identification in this study 4.6.6 The proposal protocol for identification From the identification result from Military Institute of Forensic Medicine, and the others successes in the world, we propose the protocol of stage for victims identification which depend on the different situation CONCLUSIONS Pathologic signs and lessions of drowning in forensic identification - Proportion of drowning mortality was the highest was from 15 to 29 years old (35.5%) The proportion in male (79.1%) was higher than in 24 female Drowning usually occurred in second and third quarter in year (77.9%), the highest rate was in April (15.7%) Most of victims were identified in the first drowing day (62.1%) Drowning was popularly happenned in river and spring (40.1%); caused by accident (69.2%), by suicide (7%), by homicide (0.6%), unidentification (23.3%) - Signs and exteral injuries that were value of drowning identification included: conjunctivitis (100%), lividity pattern (74.6%), rigor mortis (89.4%), foam cone (66.4%), wrinkle skin (58.1%) These signs usually were found in the first two days Other signs such as exophthalmos (100%), flared mouth (78.8%), peel skin (72%) were frequently appeared from the third day to seventh day - Signs and exteral injuries that were value of drowning identification included: fluid and foam in the airway (54.8%), pulmonary edema (88.5%), the foreign objects in the airway (35.5%), water in stomach (30.8 %) - Pathological lessions that were value of drowning identification were the laceration of aveoli (88.5%), the foreign objects in the airway (19.2%), rupture RBC in vessels and organs (50%) Diatom test played an important role in diagnosis and location of drowning Identification drowning victims by DNA analysis technique - Proportion of victims were identified by DNA analysis technique was 18.02%; Number of victims were successful identification were 31/31 victims (100%) - From 1-4 postmortem days, most of victims were identified by the normal method (83.3%-84.2%); 85% victims was required the DNA analysis for identification from 5-9 days postmortem - From 1-4 days postmortem, the nucleus analysis was used for every victim From 5-15 postmortem, the mitochondrial analysis was more preferred After 15 days postmortem, most victims was identified by mitochondrial analysis PROPOSALS Procedures and guide the collection of DNA analysis samples in identification of asphyxial victims were established Procedures of drowning victims’ identification also was developped to meet the assessment of victims' identifications when natural disasters and accidents that cause many deaths ... signs and characteristics of drowning victims Application of DNA analysis in identification of drowning victims 2 The need of the thesis The thesis is an answer for debating question regarding of. .. with proper identification method Therefore, the study ? ?Assessment the forensically pathologic characteristics and identification method of drowning victims? ?? aims to: Description of the pathologic... of pathologic characteristics of drowning and proposes the DNA analysis for identification method The description study concluded the valuable pathologic signs and characteristics for diagnosis