A Forensic Case of Suicide Ingestion of Paraquat Herbicide: New Histological Insights and Revision of the Literature

ABSTRACT

Paraquat (PQ) is one of the most widely used herbicides in the world, and poisoning is generally associated with accidental, suicidal, or homicidal events. Therefore, in the forensic context, PQ could be in various ways involved as a possible cause of death of a subject. However, even though its systemic toxicity is known, the biological effects exerted on individual viscera have been explored only to some extent, especially in case of victim's survival. Therefore, a case concerning a suicidal ingestion of PQ with survival of 3 days was deemed of interest. Clinical toxicological analyses confirmed acute PQ intoxication, and after the death of the victim, an autopsy was performed showing local and systemic signs of ingestion of a caustic substance. Histologic examination revealed marked cellular damage to the major viscera, particularly the gastroesophageal tract, liver, kidneys, and lungs, with initial alveolar fibrosis noted despite the patient's short survival. This finding represents a new element in the context of PQ lung injury, as it has not been previously documented in the literature. Thus, histological findings in lethal intoxications after survival can reveal specific peculiarities still unknown and, therefore, assume transversal relevance not only at forensic but also clinical level.

Visceral Microscopic Pattern From Suicidal Ingestion of Professional Lysoform® With Delayed Death

Lysoform® in the formulation of professional detergent is widely used in several fields, whereas its suicidal ingestion is an unusual occurrence. Therefore, the biological signs of this fatal poisoning remain unclear and elusive, similarly to the histological lesions induced by its main constituent, which is benzalkonium chloride (BZK). Furthermore, since all the deaths that has been reported in the literature occurred immediately, microscopic pictures of BZK lethal toxicity in subjects with prolonged survival have never been reported to date. Specifically, this brief communication reports the unique case of a woman who ingested professional Lysoform® to commit suicide, for which she died two weeks later. The autopsy examination showed either local or systemic signs of caustic ingestion; moreover, the histological analysis showed clear cellular damage of lungs, heart, and kidneys. In our case, toxicological investigations were not authorized as they were no longer considered significant. In this framework, the histological examination has therefore assumed a fundamental role in investigating and demonstrating the lethal effects caused by the systemic dissemination of BZK, which would otherwise no longer be investigable. Therefore, in cases of substance intoxication with prolonged survival where forensic toxicological investigations may be no longer possible or feasible, the histological examination may be the only resource to successfully observe and demonstrate its lethal effects.

Is it possible to detect lead derived from gunshot residues on decalcified human bone by means of a histochemical staining with sodium rhodizonate?

In this study we have evaluated the detectability of lead deriving from Gunshot Residues (GSR) on human bone using colorimetric techniques as well as the possible interferences of decalcification on the stainability of these particles. 22 well preserved cadavers were divided into two groups: group A enlisted 11 victims deceased because of gunshot injuries (bones and soft tissues sampled in correspondence of the entry wound of the bullet)- and group B, comprehending 11 victims deceased for natural causes (specimens sampled from intact skin areas). All the samples, after decalcification processes for bone specimens with a 14 % HCl solution, underwent standard histological procedures and were stained with hematoxylin and eosin (H&E), sodium rhodizonate (Na-R) and acidified sodium rhodizonate (Na-R-HCl 5 %). Two additional slides of soft tissues for each group were pre-treated with HCl 14 % before being stained with likewise staining. In group A, 10 samples out of 11 resulted to be negative to Na-R and Na-R-HCl 5% techniques while all the corresponding soft tissues resulted to be positive for the same staining. Additional soft tissue slides processed with 14 % HCl solution were negative in 10 cases out of 11. No sample in group B showed positivity to the staining procedures neither with nor without pre-treatment with 14 % HCl. The search for GSR residues on human bone is therefore not executable with Na-R and Na-R-HCl 5 % techniques since the essential decalcifying procedure modifies the stainability of the residues therefore adulterating the results.

Forensic - Pathological SEM/EDX analysis in prosecution of medical malpractice

The retention of gauze within the mediastinum is considered an exceptional finding. We are presenting the case of a woman, affected by aorto-mitral valvulopathy, in whose mediastinum was found, during the autopsy, a gauzome without signs of active phlogosis, which had been "forgotten" in a previous surgery, acted 14 years before the death. A 39 y.o. woman had received surgical treatment of double aorto-mitral valve substitution and tricuspid plastic. At age 53, she successfully received surgery once again at a different hospital; she then started rehabilitation therapy, during which she deceased due to sudden hematemesis with infectious multi organ failure. During the autopsy, a 5 cm long surgical gauze was found in the mediastinum. A SEM/EDX (Scanning Electron Microscopy with Energy Dispersive X-ray spectroscopy) exam was ran on the foreign body and a sample of the same gauze used in the cardiac-surgical department of the hospital the victim had passed away in, to act a comparison between the two kinds of material. The exam showed a morphological difference between exogenous fibers incorporated within the gauzome and the control gauze. This case highlights the diagnostic and interpretative challenges in finding a foreign body within the mediastinum without signs of active phlogosis. SEM/EDX investigations executed on the gauzome and a "control gauze" allowed the attribution of malpractice to the first hospital the victim had been operated in 14 years before the exitus. The SEM/EDX exam confirms its importance in correctly identifying the case, which becomes an example for similar happenings.

A particularly complex case of matricide by means of plastic bag suffocation: Case report

A rare case of homicide with plastic bag suffocation is presented in which forensic genetic investigations were carried out on the inner surface of a plastic bag placed over the head of an elderly woman, bedridden after a stroke. The results obtained suggested that she had been murdered and hinted at the perpetrator of the crime. In fact, it emerged that biological traces left by the victim matched those of her principal caregiver, her psychotic daughter, who later confessed to the crime. The old woman also had a son affected by a serious illness, whose genetic profile was found on the same bag. In a later interview, he stated that his sister had tried to kill him too, thus confirming the genetic findings and allowing the investigators to hypothesise that the daughter had used the same means to try to kill him. Based on these results, the usefulness of forensic genetic testing when investigating complex plastic bag suffocation deaths is highlighted. This peculiar case deserves interest, since no murder of this kind has ever been reported in the Italian forensic literature.