Sensitivity and specificity of EtG in hair as a marker of chronic excessive drinking: pooled analysis of raw data and meta-analysis of diagnostic accuracy studies.

BACKGROUND: To assess the debated diagnostic performance of ethyl glucuronide in the 3-cm proximal scalp hair fraction (HEtG) as a marker of chronic excessive drinking. METHODS: In July 2012/May 2013, after a systematic search through the MEDLINE, OVID/EMBASE, WEB OF SCIENCE, and SCOPUS databases, 8 studies were included in the pooled analysis that report raw single data on HEtG concentration and self-reported daily alcohol intake (SDAI). A receiver operating characteristic curve analysis and a Spearman rank-order correlation test were used. A meta-analysis was performed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses and Cochrane recommendations, comprising quality and bias assessments. RESULTS: The pooled analysis showed that 30 pg/mg could be a useful cutoff value for HEtG to detect an SDAI >60 g/d and demonstrated a parabolic direct correlation between HEtG and SDAI data [rho 0.79; 95% confidence interval (CI), 0.69-0.87; P < 0.001]. The meta-analysis found an overall HEtG sensitivity of 0.96 (95% CI, 0.72-1.00) and a specificity of 0.99 (95% CI, 0.92-1.00); a nomogram to predict the posttest probability of exhibiting the targeted condition in the general population was built. Significant variability among the included studies was detected, which was mainly explained by true heterogeneity in the presence of publication bias. CONCLUSIONS: With the available data, we conclude that HEtG is a promising marker for identifying chronic excessive drinking. Nonetheless, larger and well-designed population studies are required to draw any definitive conclusions on the significance and appropriateness of its application in the forensic setting.

Micro-CT features of intermediate gunshot wounds severely damaged by fire.

Incineration or extensive burning of the body, causing changes in the content and distribution of fluids, fixation and shrinking processes of tissues, can alter the typical macroscopic and microscopic characteristics of firearm wounds, hampering or at least complicating the reconstruction of gunshot fatalities. The present study aims at evaluating the potential role of micro-computed tomography (micro-CT) for detecting and quantifying gunshot residue (GSR) particles in experimentally produced intermediate-range gunshot wounds severely damaged by fire. Eighteen experimental shootings were performed on 18 sections of human calves surgically amputated for medical reasons at three different firing distances (5, 15 and 30 cm). Six stab wounds produced with an ice pick were used as controls. Each calf section underwent a charring cycle, being placed in a wood-burning stove for 4 min at a temperature of 400 °C. At visual inspection, the charred entrance wounds could not be differentiated from the exit lesions and the stab wounds. On the contrary, micro-CT analysis showed the presence of GSR particles in all burnt entrance gunshot wounds, while GSR was absent in the exit and stab wounds. The GSR deposits of the firearm lesions inflicted at very close distance (5 cm) were mainly constituted of huge particles (diameter >150 µm) with an irregular shape and well-delineated edges; at greater distances (15 and 30 cm), agglomerates of tiny radiopaque particles scattered in the epidermis and dermis layers were evident. Statistical analysis demonstrated that also in charred firearm wounds the amount of GSR roughly correlates with the distance from which the gun was fired. The obtained results suggest that micro-CT analysis can be a valid screening tool for identifying entrance gunshot wounds and for differentiating firearm wounds from sharp-force injuries in bodies severely damaged by fire.

Machinery-related deaths: relevance of workplace investigation and antemortem radiological data in reconstructing the fatality.

Machinery-related fatalities are one of the leading causes of traumatic occupational deaths. In our report, we present the case of a 40-year-old male who suffered a severe head trauma while working in a cut-foam industry and died despite an early craniectomy. The radiological reconstruction of the skull based on preoperative computed tomography scans disclosed a large depressed conical fracture of the left parietal bone. The 3D-reconstruction of the work area, combined with a fit-matching analysis between the machinery and the depressed skull fracture allowed us to conclude that the head was crushed between the sliding bar of the cutting device and the metallic protuberance on the opposite side. The case underlines the importance of a detailed workplace investigation and of a thorough evaluation of all circumstantial, clinical, radiological, and autopsy data in the reconstruction of machinery-related fatalities to identify any possible legal responsibilities of the worker and/or the employer.