The estimation of post-mortem interval (PMI) is of utmost importance for forensic pathologists due to its implication in medico-legal evaluations. Research over the last thirty years has sought new methods for estimating the time of death, particularly focused on human biomarkers whose concentration changes over time after death. Although most studies are based on potassium (K⁺) concentrations in blood and vitreous humor (VH), hypoxanthine (Hx) has shown great promise in assessing PMI. Following PRISMA guidelines, this systematic review addresses the PICO question: "In human cadavers, what is the role of hypoxanthine, where, and with what analytical techniques is it currently used for post-mortem interval estimation?". Twenty-four papers were retrieved. The results indicate that Hx concentration can be estimated in various biofluids, VH being the most commonly accounted for. Furthermore, different pre-analytical procedures are resorted to for sample preparation, such as several methodologies utilized to detect Hx concentration. The relationship between the so-obtained Hx levels and PMI is expressed quantitively (through regressions or correlation coefficients) or semi-quantitatively (by changes in nuclear magnetic resonance spectra). PMI estimation accuracy improves significantly when additional factors are considered (such as ambient and rectal temperature, urea concentration, body weight, and cause of death) or when new methodologies providing flexible regression models are applied. Despite the promising potential, many limitations remain. Notably, the heterogeneity of sample selection and pre-analytical/analytical phases leads to inconsistent results. Thus, much more should be done to lay procedural standards and optimize biochemistry and Hx utilization in PMI-related forensic investigations.

Background: A psychological autopsy is a post-mortem investigative tool used to carry out a retrospective reconstruction of a missing subject’s life. The method includes gathering information from all the potentially involved parties, which may indicate the relevant elements directly or indirectly to trace the victim’s experience and identify personality traits, lifestyle, and interpersonal relationships. Discussion: Psychological autopsies are mainly performed during criminal investigations to identify the cause of death and the specific circumstances (natural, accidental, suicidal, or homicidal death). In addition, from an epidemiological point of view, this method aims to collect the relevant information about an individual’s behavior, circumstances, and reasons for their death to identify common risk factors to prevent new suicides. Although less frequently, this tool can also serve other purposes, such as the legal validity estimation of pre-death actions. Moreover, it may be used to assess whether mistakes have been made in treating people undergoing medical or psychological treatment. Conclusions: Currently, this methodology still has a limited diffusion on the Italian and European scenes due to the lack of standardized guidelines and substantial relevant scientific literature. It is the main factor affecting the tool’s reliability, validity, and systematic application in forensic investigations.

HAIs (Healthcare-Acquired-Infections) have been recently the subject of judgment n. 6386 pronounced on 3rd March 2023 by the Italian Supreme Court. This sentence provided three criteria to determine whether a health facility is responsible for the patient contracting a nosocomial infection, i.e. time criterion, topographical criterion and clinical criterion. Accordingly, the healthcare facility is obliged to prove the fulfillment of a series of preventive hygiene measures specifically detailed by the legislator. Herein, the positive predictive value of these criteria ("juridic criteria") in the identification of professional liability for nosocomial infections was evaluated in comparison with clinical criteria reviewed by Infectious Disease specialists ("Infectious-Disease criteria", i.e. presence of a Multidrug Resistant Organism (MDRO); development of surgical site infection; inadequate antibiotic therapy; inadequate disinfection). Two retrospective cohorts were compared from the Portal of Telematic Services of the Ministry of Justice; 51 patients were extrapolated from Italian judgments concerning claims for Gram-negative nosocomial infections in the three-year period 2020-2022. On the other side, from the electronic database of University Hospital of Bari we extracted 349 patients affected by Gram-negative infections in the same timespan. Both "juridic" criteria and "Infectious-Disease" criteria were then applied to the full cohort after stratification for cohort of origin and after stratification for nosocomial or non-nosocomial infections. Predictive value of criteria was evaluated through receiver operating characteristic (ROC) curves and area under the curve (AUC). Overall, the incidence of definite nosocomial infections (according to final judgement or clinical records discharge letter) was 84 % in juridic cohort and 46 % in "real-world" series. Data suggested that the presence of all three juridic criteria [ROC AUC = 0.944 (95%CI = 0.924-0.963)] or the four clinical criteria [ROC AUC = 0.948 (95%CI = 0.928-0.969)] predicted well a case of nosocomial infection with professional liability. Moreover, by summarizing both criteria in a single classification system, the generated ROC curve (was the one with the highest AUC [0.9488 (95%CI = 0.928-0.969)]. Accordingly, further tests were performed, evaluating the predictive value of one juridic criterium plus at one of more Infectious-Disease criteria. Interestingly, the ROCs curves demonstrated that the presence of at least 1 juridic criteria plus at least 2 Infectious Disease criteria reached a predictive value comparable to 2 or 3 juridic criteria. The results highlight the efficiency of new criteria laid down in the judgment of the Italian Supreme Court to attribute liability for nosocomial infection despite the disputed distance between juridic and scientific decision-making process. In addition, the use of a combined score combining "juridic" and "Infectious-Disease" criteria provides a high-quality tool to be used by technical consultants to make up for lack of clinical documentation by passing judgments concerning litigation about professional liability in case of nosocomial infections. This sheds light on the possibility to face worldwide judicial inquiries with scientific rigor.

Hyperactive Delirium with Severe Agitation (HDSA) is characterized by disorientation and aggressive behavior, constituting an acute, life-threatening medical emergency that requires prompt intervention. It is frequently associated with substance use. In prehospital settings, management often involves physical restraint, force, or pharmacological sedation; however, the diagnostic criteria and medico-legal implications of HDSA remain insufficiently defined. We retrospectively analyzed seven fatal cases exhibiting HDSA presentations, as defined by the American College of Emergency Physicians (ACEP), from the archives of two university-based forensic pathology centers. A detailed multidisciplinary review by forensic pathologists and forensic psychiatrists showed that six of seven decedents were males aged 25 to 36 years who experienced sudden cardiorespiratory arrest during episodes of severe agitation. Four deaths were preceded by law enforcement involvement, and five occurred immediately following attempts at manual restraint, implicating restraint-associated asphyxia as a potentially significant factor in mortality. Toxicological analyses detected psychostimulant exposure in five cases. This study represents, to our knowledge, one of the first to employ the updated HDSA terminology to describe fatal cases within a medico-legal forensic psychiatric context.

Post-mortem interval (PMI) estimation remains a challenge for forensic pathologists, thus representing a hot topic in the research of forensic sciences. Over recent years, new methods have been proposed based on the analysis of various human biological matrices and changes in their post-mortem biochemical markers (BPMs) concentrations. Raman spectroscopy shows great promise in PMI assessment thanks to its ability to analyze complex organic materials and provide a unique fingerprint of substances. Following PRISMA guidelines, this systematic review addresses the PICO question: “In human cadavers/remains, what is the role of Raman spectroscopy, on what biological matrices, and with what analytical techniques is it currently applied for post-mortem interval estimation?“. The selected five papers reviewed point out that the applications of Raman spectroscopy in PMI estimation are now widespread in forensic anthropology, moving from the study of evolving chemical alterations of human skeletal remains over time to exploring their correlation with burial duration or PMI. The most frequently evaluated parameters were phosphate (an inorganic component of the bone/tooth matrix) and the progressive decrease in the organic bands’ peak intensity over PMI, with principal component analysis (PCA) being the preferred multivariate statistical analysis to improve the interpretation of Raman spectral data. Although Raman spectroscopy has many analytical and practical advantages, being non-destructive, rapid, and available as an hand-held device, its implementation in forensic routine casework remains limited and can only be expected to be useful in cases with longer PMI.

The estimation of the early post-mortem interval (PMI) in human corpses remains a challenging goal for forensic sciences. By exploiting label-free Raman mapping on non-treated human whole blood directly deposited on innovative nanostructured Surface Enhanced Raman Scattering (SERS) substrates, we propose a novel approach to rapidly obtain information on the presence of different levels of hypoxanthine (Hx) as a post-mortem biochemical marker (BPM). The efficacy of the method was tested on several whole blood samples from human corpses, spanning a time window between 3 and 32 h after death. The methodology, which allows the identification of metabolic and endogenous sources of Hx concentration increase, can be further engineered to develop dedicated automatable devices and holds potential for on-field applications during medical and forensic site inspections and investigations.