Günter Weiler

Immunoassays for drug screening in urine

Immunoassays are presently used worldwide for the rapid screening of drugs. Despite the fact that they are a highly valuable tool for the testing of legal and illicit drugs, there is a real risk of false-positive and false-negative findings and many pitfalls must be taken into account when these tests are used in an uncritical manner and without valid confirmation procedures. In a long-standing successful cooperation with a large psychiatric hospital, we checked doubtful and nonplausible immunochemical findings in urine with gas chromatography-mass spectrometry (GC-MS) confirmation methods. The reported case histories demonstrate typical pitfalls, for example, influence of changing nutritional habits, use of sweeteners (cyclamate), uncritical creatinine correction, impaired elimination, or cross-reactivities of simultaneous therapeutic medication. In accordance with national and international associations, immunoassays are recommended as a useful tool for screening. However, confirmation analysis with conclusive methods (GC-MS or liquid chromatography-MS) is unavoidable for valid substance identification, discrimination between active and inactive metabolites, detection of congeners, and accurate determination of concentrations in body fluids.

Multiple homicides as a result of chloroform poisoning: case report and experimental study.

Two cases (involving five murder victims) of multiple homicide by inhalational chloroform intoxication are reported. In the discussion of the findings the valence of toxicological analyses is underlined with regard to the possibility of forcible external suffocation due to occlusion of the respiratory orifices by means of a chloroform-soaked soft covering. In addition storage experiments were performed at +4, +20 and -20 degrees C with cadaver blood mixed with chloroform. The optimal solution for avoiding volatile losses was stored in glass tubes with ground glass stoppers. In cases of unclear death in which involvement of volatile substances is suspected it is, therefore, advisable to preserve an additional blood sample at -20 degrees C in glass tubes that are only opened for the analysis of volatile substances.

Differential diagnosis SIDS/non-SIDS on the basis of histological findings of petechial thymus hemorrhages

Petechial thymus hemorrhages are found most frequently in SIDS (87%), and very much more rarely in fetuses after abortion and stillbirths (55%) as well as in perinatal deaths (40%). In these groups, there was a uniform histological bleeding pattern with emphasis on the cortical zone. In non-SIDS deaths of natural causes or extrinsic suffocation in babies and infants, it could be demonstrated in 39%. In extrinsic suffocation, the thymus hemorrhages were mostly less pronounced in quantitative terms than in SIDS. In non-SIDS (without extrinsic suffocation), a hemorrhage pattern different from SIDS could be detected with hemorrhagias of different sizes and irregularly distributed over the cortex and medulla.

Postmortem in situ diagnosis of pacemakers and electrodes to detect dysfunction

Cardiac pacemakers usually are very reliable, but sometimes malfunctions of the system occur. We conceived and developed a method to judge the functionality of pacemaker systems in deceased patients. The idea was to verify the hypothesis that more dysfunctions of implanted pacemaker systems go undetected than are detected and corrected. With the aid of a pre-amplifier and a digital storage oscilloscope, pacemaker pulse signals are derived from the surface of the thorax. The derived pulse shape offers information on the functionality of pacemakers and electrodes. Additionally the lead impedance is measured with a test pacemaker and its corresponding hand-held programmer. Synchronization properties can also be assessed with an external test pacemaker. So far 262 pacemakers have been investigated yielding an anomaly rate of 15%, comprising life threatening to annoying malfunctions. These results emphasize the forensic relevance and give reason for a discussion about the natural cause of death in these cases.

Morphometrische Untersuchungen bei stenosierender Koronarsklerose und ihre Bedeutung für die Bewertung konkurrierender Todesursachen

Zusammenfassung Als wichtigster Faktor fur Koronarthrombose, Herzinfarkt und Koronartod gilt allgemein die Koronarsklerose. Postmortal lasst sich die stenosierende Koronarsklerose angiographisch und morphometrisch erfassen. Unter Einbeziehung des maximalen Stenosegrades als funktionellem Parameter und des Herzgewichtes in die quantitativen Herzbefunde (Lumenflachen und Intimaflachen der 3 Hauptaste der Koronararterien) gelingt es, uber eine statistische Trennfunktion T eine kritische Konstellation von morphologischen Daten zu erfassen, die fur ein akutes Herzversagen spricht. Ein kardialer Obduktionsbefund wird in der Regel nach individuell sehr unterschiedlichen und subjektiven Beurteilungskriterien zur Erklarung der Todesursache herangezogen. Hierbei richtet sich der ihm zugedachte Beweiswert nach den Todesumstanden und dem Fehlen oder Vorhandensein weiterer pathologischer Befunde. Konkurrierende Todesursachen konnen in Form von Erkrankungen, Verletzungen, Alkoholund Medikamentenwirkung, physischer und psychischer Belastung oder arztlicher Massnahmen vorliegen. Die quantitative Erfassung der kardialen Befunde mit einem kritischen Grenzwert fur einen akuten Koronartod erlaubt eine genauere Beurteilung solcher konkurrierender Todesursachen. Zudem kann durch diese Untersuchungsmethode auch erst die Aufmerksamkeit auf eine nicht vermutete konkurrierende Todesursache, etwa eine Intoxikation, gelenkt werden. Dies wird an Hand von 4 Todesfallen aufgezeigt.Coronary sclerosis is generally supposed to be the most important factor for coronary thrombosis, myocardial infarction and coronary heart death. Stenosing coronary sclerosis may be postmortally documented by angiography and morphometry. It is possible to obtain sufficient morphological data to suggest acute cardiac insufficiency, if the maximum grade of stenoses as a functional parameter and the heart weight are regarded in addition to the quantitative results of the three main branches of the coronary arteries (lumen and intima areas). Generally the cardiac results of autopsy are used individually and subjectively for the explanation of the cause of death. The conclusiveness of these results of autopsy depends on the circumstances of death and the existence of further pathological findings. Competing causes of death may exist in the form of illnesses, injuries, alcoholic and drug effects, physical strain and emotional stress or medical provisions. The quantitative valuation of the cardiac findings with a critical limit for an acute coronary death permits a more exact interpretation of such competing causes of death. This method of examination may also reveal an unpresumed competing cause of death, for example an intoxication. This was demonstrated by four autopsy cases.

Postmortale Differentialdiagnose und forensische Relevanz kutaner Blasenbildungen

Abstract Cutaneous blisters on a corpse are not only of forensic interest regarding their etiology and genesis but also the time of origin, particularly the problem of vital, agonal, supravital or postmortem occurrence of cutaneous blisters could be of forensic value. The aim of this work was to summarize the causative spectrum of cutaneous blisters, including poisonous plants and animals, drugs and toxic substances. The time of origin of cutaneous blisters were evaluated in selected forensically relevant cases.Zusammenfassung Für die forensische Praxis sind Blasenbildungen an der Leichenhaut nicht nur hinsichtlich ihrer Ätiologie und Genese, sondern auch in Bezug auf deren Entstehungszeit (vital, agonal, supravital, postmortal) von Interesse. Dargestellt wird das gesamte Ursachenspektrum kutaner Blasenbildungen, wobei auf solche mit forensisch-praktischer Relevanz paradigmatisch unter Berücksichtigung verschiedener Entstehungszeiten näher eingegangen wird.

Spontane Psoasblutung mit todesursächlicher Bedeutung unter antikoagulatorischer Therapie

ZusammenfassungDie häufigste Komplikation bei antikoagulatorischer Therapie sind Blutungen, wobei als bevorzugte Lokalisationen Gastrointestinaltrakt, Oropharynx, Weichteile und Urogenitaltrakt beschrieben sind. Wie häufig die Iliopsoasmuskulatur in diesem Zusammenhang betroffen ist, erscheint unklar. Es wird über 2 Fälle berichtet, bei denen eine spontane Blutung in die Psoasmuskulatur unter Antikoagulation todesursächliche Bedeutung erlangte. Im ersten Fall war die Blutung klinisch bereits erkannt und eine iatrogene Ursache angenommen worden. Beim zweiten Fall lag der Verdacht auf eine aktive Sterbehilfe bei einer fortgeschrittenen Tumorerkrankung vor; mit einer Blutung hatte niemand gerechnet. Da der Anteil der Antikoagulierten in Zukunft noch zunehmen wird, sollte man die Problematik der spontanen Blutungen stärker beachten. Gerade bei älteren Menschen können die Symptome einer Blutung in die Iliopsoasmuskulatur wie Leistenschmerz, Beschwerden im Versorgungsgebiet des N. femoralis oder Anämie leicht fehlgedeutet werden.AbstractBleeding, predominantly in the gastro-intestinal tract, oropharynx, soft tissue, and uro-genital tract are the most frequent complications encountered during anti-coagulation therapy. It is not known precisely how often iliopsoas muscles are involved. We report on two cases in which spontaneous psoas muscle bleeding during anti-coagulation therapy was relevant to the cause of death. In the first case, the bleeding had already been detected clinically and an iatrogenous cause was assumed. In the second case, active euthanasia in advanced tumour disease was suspected and hemorrhagia was unexpected. Since the number of patients receiving anti-coagulation therapy will increase in the future, the problem of spontaneous bleeding deserves more attention. Particularly in the elderly, psoas muscle bleeding symptoms such as inguinal pain and disturbances in the area supplied by the N. femoralis or anaemia may easily be misinterpreted.