Applications of microbiology to different forensic scenarios - A narrative review.

In contrast to other forensic disciplines, forensic microbiology is still too often considered a "side activity" and is not able to make a real and concrete contribution to forensic investigations. Indeed, the various application aspects of this discipline still remain a niche activity and, as a result, microbiological investigations are often omitted or only approximated, in part due to poor report in the literature. However, in certain situations, forensic microbiology can prove to be extremely effective, if not crucial, when all other disciplines fail. Precisely because microorganisms can represent forensic evidence, in this narrative review all the major pathological forensic applications described in the literature have been presented. The goal of our review is to highlight the versatility and transversality of microbiology in forensic science and to provide a comprehensive source of literature to refer to when needed.

Comparison between prostitutes' and general women's homicides: The experience of the bureau of legal medicine of Milan and Hinterland over 26 years.

We present a retrospective study of prostitutes' homicide in the Milanese area over a 26-year period (1993-2018), and compare the results with general women's homicides: 294 women were killed of whom 71 were prostitutes. In the general population, the type-victim is an Italian woman aged between 31 and 40 years suffering from no particular pathologies or drug dependence. Prostitutes are 10 years younger, mostly Italian, suffering from pathologies probably related to their activities. Prostitutes remain at high risk of violence, due to gaps in the crime prevention system.

Technical note: Preparation improvement of charred cadaveric viscera using sandison's rehydrating solution for histological analysis.

In forensic evaluation of charred corpses, internal detrimental signs may result as more significant of those observed during external examination and is often arduous to state if a victim was exposed to fire before or after death. When the histological analysis of the remaining internal viscera is necessary, the massive destruction caused by the lesion, the charring and the coarctation of the samples don't allow to give further information or to determine the remaining organic components of the viscera. This limit is determined by the intrinsic characteristics of this thermal lesivity of self-maintenance even after the exitus of the subject, worsening the initial detrimental framework. The Authors, with the purpose of improving the microscopic visualization of the samples collected from cadavers with peculiar deterioration, as in case of carbonization, suggest the use of a specific technical protocol based on the use of Sandison's rehydrating solution since the samples treated with this solution showed, at microscopic examination, a substantial histological-morphological improvement.

The importance of the postmortem interval for the diagnosis of Waterhouse­Friderichsen syndrome by Neisseria meningitidis in a series of forensic cases

The effective value of microbiological post-mortem examinations stands as fundamental in forensic cases involving microbiology. We ran these analyses on five victims, who suddenly died after showing persistent fever. The examinations were conducted between 48 hours and 10 days after death, and adrenal gland apoplexy was detected in all the cases. Microbiological examinations identified Neisseria meningitidis, which was accountable for Waterhouse­Friderichsen syndrome. Diplococci were isolated from three cadavers that underwent forensic dissection between 2 and 3 days after death. The remaining two cadavers showed polymicrobial contamination, and a polymerase chain reaction technique was necessary to identify the pathogen. We assumed that the microbial overlap could lead to diagnostic mistakes and conceal the identification of the lethal pathogen. Therefore, we suggest using molecular techniques for a postmortem interval (PMI) longer than 72 hours. Classical microbiological examination should be performed for PMI within 72 hours.

The importance of the postmortem interval for the diagnosis of Waterhouse-Friderichsen syndrome by Neisseria meningitidis in a series of forensic cases.

The effective value of microbiological post-mortem examinations stands as fundamental in forensic cases involving microbiology. We ran these analyses on five victims, who suddenly died after showing persistent fever. The examinations were conducted between 48 hours and 10 days after death, and adrenal gland apoplexy was detected in all the cases. Microbiological examinations identified Neisseria meningitidis, which was accountable for Waterhouse-Friderichsen syndrome. Diplococci were isolated from three cadavers that underwent forensic dissection between 2 and 3 days after death. The remaining two cadavers showed polymicrobial contamination, and a polymerase chain reaction technique was necessary to identify the pathogen. We assumed that the microbial overlap could lead to diagnostic mistakes and conceal the identification of the lethal pathogen. Therefore, we suggest using molecular techniques for a postmortem interval (PMI) longer than 72 hours. Classical microbiological examination should be performed for PMI within 72 hours.

Extensive study on electrocution at the Bureau of Legal Medicine of Milan (1993-2017): Determination of the current mark with scanning electron microscope/energy-dispersive X-ray analysis on paraffin-embedded samples.

Literature on electrocution in Italy is limited. The authors have focused their attention on the use of scanning electron microscope/energy-dispersive X-ray analysis in order to evaluate the current mark even on paraffin-embedded samples. A total of 24,104 autopsies were performed at the Section of Legal Medicine of Milan (1993-2017); all cases of death caused by electrocution (low and high voltage) were selected. We assessed a regular histological examination, a toxicological examination and detected metallisation with energy-dispersive X-ray spectroscopy analysis on paraffin-embedded tissues of typical current marks. We collected 27 high-voltage fatalities and five cases of low-voltage suicide electrocution; the technique revealed itself as sensitive. In all cases, microscopic examination highlighted the typical signs of electric current and thermal damage but the histochemical specific stainings for copper and iron gave negative results. Scanning electron microscope/energy-dispersive X-ray analysis, assessed on these same samples, even when paraffin-embedded, however, enabled us to detect these elements and differentiate between the various metal residues involved in the electrocution process. Based on their experience, authors advise the use of scanning electron microscope/energy-dispersive X-ray analysis on electrocution deaths to provide information for forensic diagnosis.

Pulmonary thromboembolism secondary to pelvic thrombosis related to giant ovarian tumor.

Pulmonary thromboembolism (PTE) is one of the major complications in oncologic patients. The incidence of PTE in these cases is 4 to 7 times higher than in non-oncologic patients. Ovarian tumors, specifically those of large sizes, may impair the blood flow through the pelvic veins as tumor pressure over the pelvic vessels increases the incidence of thrombosis. The authors report the case of the unexpected death of a 74-year-old female due to massive pulmonary thromboembolism, associated with an ovarian tumor almost of 15 kg of weight that filled the abdominal and pelvic cavities. The compressive effect on the walls of the pudendal and periuterine veins somehow facilitated the local thrombosis. According to the histological characterization on post-mortem samples, the mass was identified as an "atypical proliferative (borderline) mucinous tumor." The case emphasizes the important association between pulmonary thromboembolism and ovarian tumors.

Pulmonary thromboembolism secondary to pelvic thrombosis related to giant ovarian tumor

Pulmonary thromboembolism (PTE) is one of the major complications in oncologic patients. The incidence of PTE in these cases is 4 to 7 times higher than in non-oncologic patients. Ovarian tumors, specifically those of large sizes, may impair the blood flow through the pelvic veins as tumor pressure over the pelvic vessels increases the incidence of thrombosis. The authors report the case of the unexpected death of a 74-year-old female due to massive pulmonary thromboembolism, associated with an ovarian tumor almost of 15 kg of weight that filled the abdominal and pelvic cavities. The compressive effect on the walls of the pudendal and periuterine veins somehow facilitated the local thrombosis. According to the histological characterization on post-mortem samples, the mass was identified as an "atypical proliferative (borderline) mucinous tumor." The case emphasizes the important association between pulmonary thromboembolism and ovarian tumors

The detection of metallic residues in skin stab wounds by means of SEM-EDS: A pilot study.

The morphological analysis of stab wounds may often not be accurate enough to link it with the type of wounding weapon, but a further evaluation may be performed with the search for metallic residues left during the contact between the instrument and the skin. In this study, Scanning Electron Microscopy-Energy Dispersive Spectroscopy (SEM-EDS) was applied to the study of cadaveric stab wounds performed with kitchen knives composed of iron, chromium and nickel, in order to verify the presence of metallic residues on the wound's edge. Two groups of 10 corpses were selected: group A, including victims of stab wounds and a control group B (died of natural causes). Samplings were performed on the lesions and in intact areas of group A, whereas in group B sampling were performed in non-exposed intact skin. Samples were then analysed with optical microscopy and SEM-EDS. In group A, optical microscopic analysis showed the presence of vital haemorrhagic infiltration, while SEM-EDS showed evidence of microscopic metal traces, isolated or clustered, consisting of iron, chromium and nickel. Moreover, in two cases organic residues of calcium and phosphate were detected, as a probable sign of bone lesion. Control samples (group A in intact areas and group B), were negative for the search of exogenous material to optical microscopy and SEM-EDS. The results show the utility and possible application of the SEM-EDS in theidentification of metallic residues from sharp weapons on the skin.

Death due to non-traumatic hemoperitoneum in Milan 2002-2016, with focus on two cases of abdominal apoplexy (idiopathic spontaneous hemoperitoneum) and review of the literature.

Abdominal apoplexy, also known as idiopathic spontaneous hemoperitoneum, is a rare event related to sudden death, whose diagnosis and treatment is extremely challenging and whose pathologic mechanisms are still mainly unknown. It is frequently associated with vascular disorders (alterations in the vascular structures) and mainly linked to liver cirrhosis. However, the presence of hemoperitoneum may in such cases pose many challenges to forensic post-mortem examinations since the source of bleeding remains often unknown even after a careful and thorough dissection. The Authors present two cases of sudden death related to massive hemoperitoneum (4,650ml in case 1 and 5,100ml in case 2) occurred in two cirrhotic males aged 49 and 51: no traumatic injuries were detected and the source of bleeding was not identified although a careful dissection of organs and vascular structures was performed. Rare cases have been already described in the literature, only as case reports, and no systematic studies have been performed on this issue. Nevertheless, this event ought to be taken into account asa cause of sudden death in people with advanced liver disease. A general glimpse is provided among the different causal mechanisms and the challenges within forensic pathology.

Sudden perinatal death due to rupture of congenital cardiac diverticulum. Pathological findings and medico-legal investigations in malpractice charge.

Congenital diverticula of the left ventricle, very rare malformations, are determined by an abnormal embryonic development of the ventricular wall and can be isolated or associated to other cardiac anomalies. In most of the cases, these pathologies are not symptomatic and in some patients can be associated to ventricular arrhythmia, cardiac rupture with tamponade and sudden death. Authors are presenting the case of a sudden death in an 8-weeks-old newborn due to rupture of a cardiac congenital diverticulum of the left ventricle, discovered only at the moment of the autopsic examination. The parents of the victim pressed charges against the medical staff that was appointed to the cares, blaming them with malpractice. The missed diagnosis of a cardiac congenital diverticulum of the left ventricle, a rare pathology, reflects the trickiness of the medical management that can lead to medico-legal controversies and, even though such rare conditions must be always taken into consideration when investigating possible dysfunction causing the death, diagnostic difficulties, in the case in exam, justify the missed diagnosis intra-vitam of cardiac ventricular diverticulum.

One Hundred and One Cases of Plastic Bag Suffocation in the Milan Area Between 1993 and 2013-Correlations, Circumstances, Pathological and Forensic Evidences and Literature Review.

Plastic Bag Suffocation is a rare cause of death in developed countries and almost unknown in the rest of the world. This study aims to retrospectively evaluate cases of PBS _asphyxia in Milan's Department of Legal Medicine from 1993 to 2013. Cases were selected from the database of 21,472 autopsies performed in the considered timeframe. One hundred and one cases were considered to be cases of Plastic Bag Suffocation, comprised of 100 suicides, no accidental events and 1 homicide. The most relevant elements pertaining to this type of death were evaluated for both the corpses and the crime scenes. From this study the typical PBS victim is an adult male, aged 52.3 years on average, depressed or afflicted by chronic or terminal diseases, and found at home. In 42.6% of cases, the victims were found with the plastic bag still positioned over their head, fastened by tying. Also common among these cases are drugs, alcohol and chemical abuses. According to the collected data, it is impossible to outline a pathognomonic detrimental background that leads to this cause of death. Crime scene investigation is, therefore, the one and only technical resource for evaluating these cases.

The medico-legal observation of an aggressive urogenital fibromatosis with isolated development not related to any traumatic event.

Desmoid tumor is a fibroproliferative neoplasm with an intermediate malignancy and it can be localized in every bodily district: some locations are considered exceptional, like the urogenital localization. The Author point out a rare case of giant idiopathic scrotal fibromatosis that was found during an autopsy. A widower, that lived alone in poor hygienic conditions, was found dead in his house. The Judicial Authority ordered the autopsy, that was performed two days later at the Medico-Legal Section of Milan University. External examinations revealed only the considerable dimension of the scrotum (cm 24 × 41). The cause of death was fixed in a cardiac tamponade due to a natural heart laceration localized in correspondence of a transmural infarction. The toxicological exam resulted negative, while the histopathological and immunohistochemical analysis qualify the scrotal mass as a desmoids tumor. Due to the absence of predisposing conditions and of fibroproliferative infiltration in bladder and retroperitoneal space, the neoplasm was configured as an idiopathic desmoid tumor. The presented case gives the reason for the discussion concerning medico-legal aspects that are typical of rare neoplasms.

Fatal air embolism during endoscopic retrograde cholangiopancreatography (ERCP): An 'impossible' diagnosis for the forensic pathologist.

Fatal air embolism related to endoscopic retrograde cholangiopancreatography is a very rare phenomenon. The authors describe the case of a 51-year-old female patient who developed this mortal complication; a computed tomography (CT) examination was performed in articulo mortis by the physicians. Autopsy was unreliable because of bizarre post-mortem changes (reabsorption of intra-cardiac gas vs. conservation of intra-cranial gas) and a lack of strong diagnostic value of histological findings. The right diagnosis was possible thanks only to the CT examination that permitted the assumption of this possible cause of death before the autopsy and to prepare the necessary procedures to recognise and probe air embolism. This case exemplifies how early post-mortem imaging can be crucial to avoid a wrong diagnosis.

Two decades of adolescent suicides assessed at Milan University's medicolegal unit: Epidemiology, forensic pathology and psychopathology.

AIM: to analyze the cases of suicide committed by adolescents in and around the city of Milan over a 20-year period (1993-2012). MATERIALS AND METHODS: cases of suicide involving individuals between 10 and 19 years of age were drawn from 20,757 autopsies performed by the Medico-legal Unit at Milan University. Seventy-eight cases were considered (20 females and 58 males, with the ratio of 1:2.9), and their clinical and circumstantial histories, epidemiology, forensic pathology and psychopathological issues were analyzed. RESULT: Adolescents were involved in 2.23% of all suicides committed in Milan during the period examined. The "mean" victim is a male without psychiatric disease, aged between 16 and 19, that commits suicide outdoors. CONCLUSIONS: In the majority of cases, there were no premonitory signs, nor any particular contingent or remote reason that might explain these violent deaths, which therefore remain "impulsive".

Characterisation of the weapon used in a patricide by SEM/EDS analysis of a microscopic trace from the object.

This article presents a case of patricide. The murder was characterised by multiple blunt traumas and asphyxia. A mass of contused wounds was localised to the head and neck, and included the complete avulsion of the left eye (by an unknown tool), which was recovered near the cadaver. This case is of interest due to the possibility of identifying microscopic traces of the object that was used for the homicide by examining the skin margins around the ocular injury. The analysis was conducted using scanning electron microscopy combined with energy dispersive X-ray analysis (SEM/EDX). Analysis of the skin margins allowed microscopic inorganic traces to be detected, which were identified as ceramic material. This result focused the attention of the investigation on a small fish-shaped statue that had been previously found by the police when examining the crime scene. The use of SEM/EDX was therefore essential in determining a match between the microscopic traces detected on the perilesional skin and the composition of the statue. This led to the suspicion that the statue was the murder weapon.

An unusual case of homicide with a crossbow and a hunting knife.

Traumatic lethal injuries caused by crossbows are a rarity in forensic pathology. They occur as accidents, suicide and, more rarely, as murders. We report a case of murder received at the Institute of Legal Medicine in Milan carried out by two weapons - a crossbow and a hunting knife - that resulted in multiple thoraco-abdominal wounds. The case is also rare because of the unique circumstances involving the victim - a local service psychiatrist - and the perpetrator - a former medical specialist in psychiatry, suffering from a delusional psychotic disorder. The crossbow was the decisive instrument in the realization of the murder; it was chosen with premeditation for its high destructive capacity and the fact that it was easily obtainable, and it was used with darts that were specially modified to increase its harmful capacity. The presented case, as well as providing an opportunity to highlight the damaging effects of a rarely used weapon, stresses the problems inherent with access to tools such as the crossbow that are used in sport, and which are potentially dangerous but easily accessible, even to those with serious mental disorders, rendering them legally unfit for using firearms.

Suicide drowning in the non-coastal territory of Milan.

INTRODUCTION: A cadaver in water sets a relevant issue for the forensic pathologist, concerning the differential diagnosis between homicide, suicide, accidental event, and natural death in water. In the present study, the drowning suicides in a non-coastal territory are analyzed, discussing the main diagnostic difficulties, the preventive intervention, and the strategies for outlining the profile of a "mean victim" that is at risk of committing suicide by drowning. METHODS: The cases of drowning suicide were extrapolated by the database of the 21,472 autopsies performed at the Civic Morgue of Milan, in the period between 1993 and 2013. RESULTS: Drowning represents the fifth cause of suicide registered in Milan for the study period, with 139 cases (3.8% of all suicides). Victims were mainly elderly males (61-80 years old) with a history of psychiatric diseases in pharmacological therapy; they committed suicide mainly during summer, in the rivers. The diatoms test was positive in 82 cases (59%) and highlighted typical taxa of fresh water. Alcohol and illicit drugs were not noticed, at high levels. CONCLUSION: Drowning suicide occurs even in a non-coastal territory, far from the sea, if there is an easy access to the water: specifically, many natural and artificial waterways in the Milan district represent a high-risk factor predisposing the drowning suicide.

Preservation of histological structure of cells in human skin presenting mummification and corification processes by Sandison's rehydrating solution.

INTRODUCTION: To overcome the difficulties of construction and interpretation of microscopic material from corpses presenting mummification and corification processes, a variety of techniques and tricks are used: in this research the results of applying the Sandison's rehydrating solution are presented, generally used in archeological field on Egyptian mummies of different ages, in human cadaveric material in an advanced state of decomposition. MATERIALS AND METHODS: Nineteen skin specimens were taken from corpses presenting corification and mummification processes, discovered in a time ranging between one and four months and exhumed after 11 years. Each biological sample was divided into two parts: one, directly fixed in buffered formalin 10%; the other, preliminarily treated with the Sandison's rehydrating solution and, therefore, post-fixed in 10% buffered formalin. All samples were then carried out the routine histological preparation, and the sections were stained by hematoxylin-eosin and by other histochemical stains. RESULTS: Under the microscope, the samples placed directly into formalin, showed marked structural changes of the various components, while those previously rehydrated with the Sandison's rehydrating solution allowed the clear recognition of different structures. CONCLUSIONS: The use of the Sandison's rehydrating solution on skin samples presenting corification and mummification processes, preserving significantly its general setting, stands as an indispensable procedure in the study of such cases.

The stalking of lawyers: a survey amongst professionals in milan.

This is the first study focused on the stalking of lawyers. The authors hypothesized that these professionals are at risk of being stalked by their clients and that this stalking is ascribable to RECON type I.B. A random sample of lawyers was survived. 37.3% of 166 respondents revealed to have been stalked: not only by clients, but also by adversaries and colleagues. Data seem to confirm that the stalking of lawyers mainly belongs to RECON type I.B. Female lawyers were at greater risk than male lawyers. In family law cases, the professionals tended to be stalked by the former husbands of the lawyers' clients (p < 0.01). Several female lawyers-but no male lawyers-were threatened with harm to their family members (p < 0.05). Most of the stalking victims described psychological effects of being stalked. Who suffered physical aggression or repercussions on work was more likely to lodge a complaint (p < 0.01).