G. Fechner

The application of selected histochemical and immunohistochemical markers and procedures to the diagnosis of early myocardial damage

SummaryHistochemical (= HIS) methods (haematoxylin-eosin, luxol fast blue, chromotrope aniline blue) and various immunohistochemical (= IH) markers (myoglobin, desmin, fibrinogen, complement C5b-9) were applied in parallel to test the efficiency, specificity and sensitivity for the recognition of early ischemic myocardial damage. The whole series was subgrouped into cardiac deaths (N= 35) and controls (N= 13). Cardiac deaths were sub-divided into 3 groups: l. infarction visible in gross examination (N = 15), 2. coronary thrombosis without infarction (N = 11), 3. stenosing coronary athero-sclerosis without infarction (N = 9). The control group (group 4) consisted of unnatural deaths with presumed short agonal periods (N = 13). Group 1 cases usually exhibited extended coagulation necrosis of the diffuse type and the contraction type in combination (1 exception). Group 2 showed mainly a patchy type of coagulation necrosis and contained 1 case where all methods failed to react and 3 more cases where only the HIS methods failed to react. Group 3 and 4 were associated with a disseminated type of single and/or grouped fibre necrosis. — In addition, the average reaction strengths showed a decrease from group 1 to group 4 which was more pronounced in the HIS reactions compared with the IH reactions. One case in group 1 showing negative IH reactions cannot be explained. Positive IH reactions observed in a few cases in group 2 contrasting with negative HIS reactions would indicate a greater sensitivity of this methodology and this interpretation also applies to groups 3 and 4. From pathophysiological considerations, the positive cases in groups 3 and 4 can be well explained. — The results show that selected application of a single criterion to the diagnosis of early myocardial infarction and/or ischemic fibre damage cannot resolve the diagnostic problem. However, a selected set of HIS/IH methods and the synoptic interpretation of all findings will improve the detection of early myocardial infarction/ischemic damage.ZusammenfassungHistochemische (= HIS) Methoden (Hämatoxylin-Eosin, Luxol Fast Blue, Chromotrop Anilin-Blau) und verschiedene immunhistochemische (= IH) Marker (Myoglobin, Desmin, Fibrinogen, Complement C5b-9) kamen nebeneinander zur Anwendung, um die Effizienz, Spezifität und Empfindlichkeit zur Erkennung früher ischämischer Herzmuskelschäden zu überprüfen. Das Untersuchungskollektiv war unterteilt in Herztodesfälle (N= 35) und Kontrollen (N= 13). Die Herztodesfälle waren in drei Gruppen unterteilt: 1. Makroskopisch erkennbarer Infarkt (N= 15), 2. Koronarthrombose ohne Infarkt (N = 11), 3. stenosierende Koronararteriensklerose ohne Infarkt (N = 9). Die Kontrollgruppe (4.) bestand aus nicht-natürlichen Todesfällen mit vermuteten kurzen Agonie-Zeiten (N = 13). Die Fälle der Gruppe 1 zeigten normalerweise eine ausgedehnte Koagulationsnekrose mit einer Kombination des diffusen Typs und des Kontraktionstyps (eine Ausnahme). Die Fälle der Gruppe 2 zeigten einen herdförmigen Typ der Koagulationsnekrose. Sie enthält ferner einen Fall, in welchem alle Methoden versagten und drei Fälle, in welchen die HIS Methoden versagten. Positive Fälle der Gruppen 3 und 4 zeigten einen disseminierten Typ einzelner oder gruppierter Fasernekrosen. — Zusätzlich zeigten die durchschnittlichen Reaktionsstärken eine Abnahme von Gruppe 1 nach Gruppe 4. Diese Abnahme war in den HIS Reaktionen ausgeprägter als in den IH Reaktionen. Ein Fall der Gruppe 1 mit negativer IH findet keine Erklärung. In einigen Fällen der Gruppe 2 wurden positive IH Reaktionen bei negativen HIS Reaktionen beobachtet, was auf eine größere Empfindlichkeit der IH Methodologie hinweist; diese Interpretation gilt ebenfalls für die Gruppen 3 und 4. Aus pathophysiologischen Überlegungen lassen sich die positiven Fälle der Gruppen 3 und 4 gut deuten. — Die Ergebnisse zeigen, daß die isolierte Anwendung eines einzelnen Kriteriums zur Diagnostik des frühen Myokardinfarkts und/ oder des ischämischen Faserschadens dieses diagnostische Problem nicht lösen können. Jedoch wird ein ausgewählter Satz von HIS/IH Methoden sowie die synoptische Interpretation aller Befunde die Erkennbarkeit des frühen Myokardinfarkts/ischämischen Schadens verbessern.

Fatal neglect of the elderly.

Abstract Maltreatment of the elderly is a common problem that affects more than 3% of the elderly. We report on two cases of fatal neglect. Risk factors of victims and caregivers were analysed in the context of the social history. In both cases, the victims had a dominant personality and the abusers (the sons) had been strictly controlled and formed by the parent. The victims showed typical risk factors such as living together with the abuser, isolation, dependence on care, income and money administration. Initially, the victims declined help from outside and self-neglect occurred. The unemployed perpetrators lived in social isolation and depended financially and mentally on the victims. In both cases no mental illness was present but there was a decrease of social competence. Legal medicine is predominantly involved in fatal cases in connection with external post-mortem examinations and autopsies. Also in the living, the medico-legal expert can assist in the identification of findings in elderly persons in cases of suspected abuse.

Detection and analysis of tracers in experimental drowning.

Abstract In animal experiments, studies on the mechanisms involved in drowning were carried out using latex and gold tracers of defined size and concentration. The tracers were detectable by fluorescence microscopy (latex tracers) and by electron microscopy (gold tracers) in the lungs, kidneys and lymph nodes and were analysed further by X-ray microanalysis using a transmission scanning electron microscope. Tracers with small diameters were shown to penetrate intercellular gaps of the alveolar epithelium and the larger tracers were incorporated into the epithelial and endothelial cells by active pinocytotic mechanisms thus passing through the air-blood barrier. The detection and analysis of tracers in organs of the systemic circulation originating from the immersion fluid can assist in understanding the pathophysiology of drowning and in some selected cases, in making a more definitive diagnosis.

Immunohistochemical investigations to demonstrate vital direct traumatic damage of skeletal muscle.

SummaryThe muscle proteins actin, myosin, desmin and myoglobin were investigated in traumatically damaged human and animal skeletal muscle using an immunohistochemical PAP-method. A depletion of all the proteins investigated was observed in muscle fibres damaged in the antemortem period. The antigens could however also be demonstrated in the otherwise empty sarcolemma, the discoid disintegration zones of the fibres and between the fibres. The depletion begins immediately after the trauma and myoglobin is the first to be affected. No such changes could be observed after post mortem muscle damage. The antigens could be demonstrated until 72 hours postmortem. The demonstration of protein depletion is an important addition to the light microscopical findings in vital muscle alterations.ZusammenfassungAn traumatisch geschädigter menschlicher und bei Tierexperimenten gewonnener Skelettmuskulatur wurden immunhistochemisch mit der PAP-Methode die Muskelproteine Aktin, Myosin, Desmin und Myoglobin dargestellt. Bei vital traumatisierter Muskulatur kommt es zu einer Depletion aller untersuchter Proteine aus der verletzten Muskelfaser. Die Antigene können aber in den sonst leeren Sarkolemm-Schläuchen, den diskoiden Faserzerfallszonen und auch außerhalb der Fasern nachgewiesen werden. Die Depletion beginnt Minuten nach dem Trauma, am frühesten beim Myoglobin. Bei postmortaler Traumatisierung waren die Veränderungen nicht nachweisbar. Die Antigene waren bis 72 Stunden postmortal stabil. Der Nachweis der Muskelprotein-Depletion stellt eine wichtige Ergänzung zu den lichtoptischen Kriterien vitaler Muskelfaseralterationen dar.

Fatal intoxication due to excessive dichloromethane inhalation

A 22-year-old white male was found dead at his working place in a car lacquering company. He had removed lacquer residues by using a solvent containing dicloromethane (DCM) without using a gas mask. Pathology revealed signs of asphyxiation with obvious petechial bleedings and expressed microthrombosis of the pulmonary arteries. Toxicological analysis showed excessive concentrations of DCM which are inhaled due to exposure of extreme air concentrations.

The distinction between lacerations and cuts in ligaments and tendons

In contrast to skin wounds the characteristic forensic features of lesions of ligaments and tendons have rarely been investigated. However, in a suspected homicide the question became crucial whether an isolated discontinuity of the posterior atlanto-occipital membrane was caused by a rupture mechanism or by a cut. In order to re-evaluate the associated criteria experimental lesions were made in ligaments and tendons and examined histologically. From these experiments the following criteria could be established:Lacerations exhibit complete destruction of the tissue texture with microruptures and splitting of fibres in the adjacent region. Such wound edges have an irregular structure and fibres near the rupture site exhibit variable thicknesses due to traction.Incisions exhibit smooth wound edges with no disturbance of the tissue texture. The thickness of fibres near the rupture site is regular. These results were obtained by light microscopical examination and confirmed using electron microscopy. Under controlled experimental conditions the forces necessary to rupture tendons with a diameter of 1 mm varied between 50–70 Newton (N). In the suspected homicide, the lesion of the posterior atlanto-occipital membrane was examined visually and histologically and was compared with the experimentally established criteria. Based on these criteria the lesion could be identified as an incision which had probably been caused accidentally while severing the medulla during the first autopsy and was therefore not connected with the cause of death.

Backstabbing—a report of an unusual case

A case of a 25-year-old male with a deep knife stab injury in the back is reported. The stab wound penetrated the left thorax and the left lung was injured, a thoracotomy was performed and the patient survived. The injured man could not remember what had happened, his bag was missing and the incident was therefore considered to be due to a robbery. Further results of the police investigations and the forensic pathology inspection revealed an extremely unusual accident constellation.

Mycotic cerebral vasculitis in a paediatric cardiac transplant patient excludes misadventure.

We present the case of a 10-year-old girl with cardiomyopathy who received a heart transplant. Due to organ rejection, the dosage of immunosuppressive agents was increased postoperatively. The patient complained of intermittent headaches in the following days and developed a haemorrhagic necrosis of the left thalamus. A week later, an oral dose of cyclosporin A was accidentally given intravenously, and 2 weeks later a recurrent subarachnoid haemorrhage of unknown origin was diagnosed. The clinical course was then characterised by progressive deterioration resulting in coma, fluctuating brain stem symptoms and the development of a massive cerebral oedema with subsequent brain death. A coroners autopsy was instigated to investigate a claim of medical misadventure. Neuropathological investigations found a focal infiltration of fungal hyphae in the left posterior cerebral artery resulting in necrosis of the vascular wall and thus explaining the source of the recurrent subarachnoid haemorrhage which eventually resulted in the girls death. Medical misadventure due to the administration of cyclosporin was not directly responsible for the death of this patient. This case illustrates that it is of paramount importance to copiously sample and investigate the basal cerebral arteries in cases of subarachnoid haemorrhage of unknown origin, in particular in a medico-legal context.