Forensic application of three interstitial pneumonia markers: search for new pneumonia markers in dead bodies.

In forensic cases, detailed identification of pneumonia is important. Our objective was to statistically determine the applicability of three interstitial lung disease (ILD) markers for forensic diagnosis using serum collected from dead bodies with various postmortem intervals (PMIs). We retrospectively analyzed the levels of postmortem serum Krebs von den Lungen-6 (KL-6) and pulmonary surfactant-associated proteins A and D (SP-A and SP-D) using 221 samples obtained during forensic autopsy at our facility from 2019 to 2023. We evaluated the diagnostic efficacy of ILD markers for various pneumonias against the pathological diagnosis, and examined the assessment of the severity of ILD. When comparing the ILD group with bacterial pneumonia (BP) versus the control group, there was a significant increase in KL-6 in the ILD group. When comparing the severe ILD (SILD) group with the mild ILD (MILD) group, there was a significant increase in KL-6 and SP-D in the SILD group. The optimal cutoff values for differentiating SILD were 607.0 U/mL for KL-6, 55.5 ng/mL for SP-A, and 160.0 ng/mL for SP-D, and the sensitivity/specificity (%) of KL-6, SP-A, and SP-D for SILD were 84.1/95.2, 55.6/85.7, and 66.7/74.6, respectively. This is the first study to examine KL-6 in postmortem serum in forensic medicine. By analyzing dead bodies with various PMIs, our results confirmed statistically that postmortem serum KL-6 specifically detects ILD, postmortem serum SP-A has high sensitivity to lung injury, and postmortem serum SP-D is potentially useful in assessing the severity of ILD.

A suicide case of liquid nicotine intoxication.

A man in his 50 s, who was found vomiting and in a disturbed state when the emergency medical team arrived, then went into cardiopulmonary arrest during transport and died without responding to resuscitation. The hospital initially suspected that the death may have been caused by internal causes, but since the deceased had previously been transported to the hospital in a suicide attempt, the hospital called police regarding suspicions of unnatural death. The police investigation revealed two empty bottles of nicotine liquid for e-cigarettes in his house and a search history of "nicotine suicide" on his cellphone. In a forensic autopsy, he was found to be highly obese, and abundant fat deposits were observed in his organs. A stent was placed in the aorta, but no abnormality was found. There was no obvious stenosis or obstruction in the coronary arteries. Drug screening using liquid chromatography tandem mass spectrometry (LC-MS/MS) was performed on cardiac blood, urine, and stomach contents collected at autopsy, which revealed the presence of some medical products such as aripiprazole, nicotine, and cotinine. Further quantitative testing revealed high concentrations of nicotine in all samples. The left and right femoral venous blood concentrations were above the lethal dose, suggesting that arrhythmia or respiratory failure due to nicotine intoxication was the cause of death. With the widespread use of e-cigarettes, high concentrations of nicotine are readily available, and case reports of serious nicotine addiction are increasing. It is important to always consider addiction when conducting forensic evaluations in the medical field.

A combination of bowel wall thickness and submucosa index is useful for estimating endoscopic improvement in ulcerative colitis: external validation of the Kyorin Ultrasound Criterion.

BACKGROUND: Endoscopic improvement (EI; a Mayo endoscopic subscore of 0 or 1) is considered a therapeutic target in ulcerative colitis (UC) treatment. The potential to estimate EI non-invasively is an advantage of intestinal ultrasound (IUS). In a previous study, we developed a new sonographic parameter, the submucosa index (SMI), calculated as the ratio of the submucosal thickness to bowel wall thickness (BWT), and reported that combining BWT and SMI results in a practical and promising criterion for estimating EI without color Doppler assessment. This study aimed to validate the EI estimation ability of our B mode-based criterion, the 'Kyorin Ultrasound Criterion for UC' (KUC-UC; BWT < 3.8 mm and SMI < 50%), using an external cohort. METHODS: Patients with UC who underwent IUS and colonoscopy within 15 days without a treatment change between examinations were included. IUS findings, including BWT, SMI, and modified Limberg score for vascularity of the colon, were assessed. RESULTS: Forty-four test pairs of IUS and colonoscopy examinations in a total of 122 colonic segments were analyzed. The KUC-UC showed positive predictive value (PPV) of 94.6% and negative predictive value (NPV) of 80.0% for EI. In comparison, PPV and NPV were 85.4% and 79.0%, respectively, for the common criterion BWT of < 3 mm, and 83.0% and 82.7% for the validated Milan Ultrasound Criteria (a score of ≤ 6.2). CONCLUSIONS: External validation showed that the KUC-UC using only B mode findings without complicated calculations is a feasible and accurate sonographic criterion for estimating the EI of UC.