H. W. Schütz

Age estimation: The state of the art in relation to the specific demands of forensic practise

Abstract Age estimation in cadavers, human remains and living individuals may clarify issues with significant legal and social ramifications for individuals as well as for the community. In such cases methods for estimating age should fulfil the following specific demands: (1) they must have been presented to the scientific community, as a rule by publication in peer-reviewed journals, (2) clear information concerning accuracy of age estimation by the method should be available, (3) the methods need to be sufficiently accurate and (4) in cases of age estimation in living individuals principles of medical ethics and legal regulations have to be considered. We have identified and summarized the methods that essentially fulfil these specific demands. In childhood and adolescence morphological methods based on the radiological examination of dental and skeletal development are to be recommended. In adulthood, the accuracy of most morphological methods is much reduced. Here a biochemical method based on aspartic acid racemization in dentine provides the most accurate estimates of age, followed by special morphological dental and skeletal methods. The choice of method has to take account of the individual circumstances of each case. Most methods require either the consultation of specialised and trained scientists or an adequate calibration by the “user”. Very few attempts have been made to find common standardisation, calibration and evaluation procedures or to develop means of quality assurance for methods of age estimation. Efforts in these directions are necessary to guarantee quality standards and adequate answers to the important legal and social issue of age estimation in forensic medicine.

A review of the methodological aspects of aspartic acid racemization analysis for use in forensic science

Accurate age determination of adult cadavers and human remains is a key requirement in forensic practice. The current morphological methods lack accuracy and precision, require specialist training and are costly. The use of aspartic acid racemization (AAR) in human dentine provides a simple, cost-effective solution and the method can achieve accuracies of +/- 3 years at best. Currently, there are differences in AAR methodology between laboratories which produce different results on the rate of racemization in teeth. These inconsistencies must be resolved if the technique is to be successfully applied to age determinations in forensic cases. This paper reviews the differences in protocol which have been used, discusses how each method will affect the results obtained from AAR analysis and gives recommendations for optimization of the methological protocol as a first step towards international standardization.

Quality assurance in age estimation based on aspartic acid racemisation

Abstract Estimates of the age of living and dead individuals, obtained in order to answer legal or social questions, require minimum quality standards in order to guarantee data quality. We present an outline strategy (with recommendations) for the attainment of quality assurance in age estimation based on aspartic acid racemisation. The strategy is based on a definition of minimum standards for laboratories, including documentation of procedures, methodology and levels of expertise, and the formulation of guidelines for intralaboratory and interlaboratory quality control.

The extent of aspartic acid racemization in dentin: a possible method for a more accurate determination of age at death?

SummaryIn the current study the objective was to find to what extent a reliable determination of age at death is made possible by establishing the degree of aspartic acid racemization in the dentin of teeth. The results of the investigation of 46 teeth are in agreement with the values found by other authors. The method presented makes a reproducible and accurate estimation of age possible. We intend to elaborate and improve this promising method for determination of age at death. The relevant points are presented here.ZusammenfassungEs wurde geprüft, inwieweit eine zuverlässige Lebensaltersbestimmung durch Feststellung des Razemisierungsgrades von Asparaginsäure in Zahndentin möglich ist. Die Ergebnisse der Untersuchung von 46 Zähnen stimmen gut mit den von anderen Autoren gefundenen Werten überein. Offenbar ermöglicht das vorgestellte Verfahren eine gut reproduzierbare und genaue Lebensaltersbestimmung. Diese vielversprechende Methode zur Altersdiagnose soll jedoch noch ausgearbeitet werden; entsprechende Gesichtspunkte werden vorgestellt.

Age estimation in biopsy specimens of dentin.

Determination of age at death on the basis of aspartic acid racemization in dentin is one of the most reproducible and accurate methods. In Germany, age estimation by this method has so far generally not been applied to living persons, since the extraction of a tooth exclusively for age estimation when it is not medically indicated is regarded as ethically and legally problematic. The development of a biopsy technique applicable to dentin took place against this background. Testing the technique and analysis of dentinal biopsy specimens revealed that the biopsy technique is a low-risk procedure that causes only minor discomfort to the affected person. It is readily practicable and facilitates standardized specimen removal. The relationship between the extent of aspartic acid racemization in dentinal biopsy specimens and age is very close, facilitating age estimation. A prerequisite for accurate results is the performance of biopsies under strictly standardized conditions. If this is guaranteed, age determination on the basis of aspartic acid racemization in dentinal biopsy specimens appears to be superior in precision to most other methods in living persons and can be used for all age groups.

Fatal intoxication with a decalcifying agent containing formic acid

Abstract A fatality caused by ingestion of a decalcifying agent containing formic acid is reported. Quantitative analysis of formic acid in the form of its methyl ester was performed in different body fluids and organ samples using head-space gas chromatography with flame ionization detection. The blood taken at the time of admission to hospital had a concentration of 370.3 μg/ml, which declined to 13.9 μg/ml after 6.5 h of haemodialysis. Post-mortem concentrations were 855.4 μg/ml (heart blood), 2712 μg/ml (gastric contents), 1128 μg/ml (haemorrhagic fluid from abdominal cavity), 3051 μg/ml (bile), 2664 μg/ml (contents of small intestine), 442.7 μg/g (liver) and 542.3 μg/g (kidney). The most important morphological findings for differentiating between oral and respiratory ingestion were ulceration of the oropharynx and the oesophagus as well as extensive necrotic lesions in the stomach and the duodenum without perforation. Death was caused by massive acidosis, haemolysis, bleeding complications, hepatic and renal failure. Toxicological and morphological findings revealed that a considerable amount of formic acid had been ingested orally with a suicidal intention.

Measurement of digitalis-glycoside levels in ocular tissues: A way to improve postmortem diagnosis of lethal digitalis-glycoside poisoning? II. Digitoxin*

SummaryPrompted by animal studies reporting the accumulation of digitalis-glycosides in ocular tissues, we investigated whether measurement of digoxin levels in human ocular tissues can improve the postmortem diagnosis of lethal digoxin intoxication. Digoxin was measured in the vitreous humor and choroid-retina of patients who had received in-patient treatment with digoxin prior to death (therapeutic group) and in a single case of suicidal intoxication. The results were compared with the digoxin levels in the femoral vein blood, myocardium, kidney and liver, and evaluated in light of the medical history of each patient. In the therapeutic group the mean digoxin level was higher in the choroid-retina than in other tissues and body fluids. The range of variation in levels in the choroid-retina following therapeutic doses was comparable to that in the other tissues. An extremely high level of digoxin was present in the choroid-retina in the case of suicidal intoxication. In all cases, levels in the vitreous humor were very low compared to those in the choroid-retina. Hence, it is unlikely that significant distortion of choroid-retinal levels occurs due to postmortem diffusion of digoxin into the vitreous body. Our results indicate that measurement of digoxin levels in the choroid-retina can aid the postmortem diagnosis of lethal digoxin intoxication.ZusammenfassungNachdem von anderen Autoren tierexperimentell hohe Digitalisglykosidkonzentrationen in okulären Geweben nachgewiesen werden konnten, sollte die Frage geklärt werden, ob durch Bestimmung der Digoxinspiegel in Augengeweben ein Beitrag zur Verbesserung der postmortalen Diagnostik von tödlichen Digoxinintoxikationen geleistet werden kann. Bei mit Digoxin behandelten, in Kliniken verstorbenen Patienten (therapeutisches Kollektiv) sowie in einem Fall einer suicidalen Vergiftung wurden Digoxinkonzentrationen in Glaskörperflüssigkeit und Choroidretina bestimmt. Die in den okulären Geweben bestimmten Werte wurden den Digoxinspiegeln in Femoralvenenblut, Myocard, Niere und Leber gegenübergestellt und unter Berücksichtigung anamnestischer Daten interpretiert. In der Choroidretina wurden im therapeutischen Kollektiv Digoxinkonzentrationen gefunden, die im Mittel deutlich über den in den übrigen Organen bestimmten Werten lagen. Die Streuung der Choroidretinakonzentrationen nach therapeutischer Dosierung war mit der Streuung der übrigen Gewebespiegel vergleichbar. In dem Intoxikationsfall wurde eine ausgesprochen hohe Choroidretinakonzentration festgestellt. Im Vergleich zu den Choroidretinawerten waren die Glaskörperflüssigkeitsspiegel in allen Fällen sehr niedrig; mit einer wesentlichen Verfälschung der Choroidretinakonzentrationen durch eine mögliche Diffusion des Digoxins in den Glaskörper ist danach nicht zu rechnen. Nach unseren Untersuchungsergebnissen ist die Bestimmung des Digoxinspiegels in der Choroidretina in fraglichen Vergiftungsfällen sinnvoll.

Commentary onOhtani S, Matsushima Y, Kobayashi Y, Kishi K. Evaluation of Aspartic Acid Racemization Ratios in the Human Femur for Age Estimation. J Forensic Sci 1998;54(5):949–953

Commentary on Ohtani S, Matsushima Y, Kobayashi Y, Kishi K. Evaluation of aspartic acid racemization ratios in the human femur for age estimation. J Forensic Sci 1998;43(5):949–953.

Stellenwert des „Medikamenten-Screenings” in der Therapie chronischer Schmerzen

ZusammenfassungEinführung: Die Pharmakotherapie hat einen hohen Stellenwert bei der Therapie chronischer Schmerzen. Klinische Untersuchungen zeigen allerdings, daß verordnete Medikamente häufig nicht korrekt eingenommen werden; dies bestätigten eigene Erfahrungen in der schmerztherapeutischen Praxis durch z.T. sehr überraschende Befunde eines Medikamenten-Screenings im Urin der Patienten. Derartige Urinuntersuchungen bieten somit ein Instrument zur Qualitätssicherung, dessen Grundlagen und praktische Anwendung in einem Überblick dargestellt werden. Ziele eines Medikamenten-Screenings: Das Screening soll die Umsetzung einer Therapie kontrollieren, die Bewertung von Nebenwirkungen ermöglichen, nicht verordnete Beimedikation aufdecken sowie Entzugstherapien sichern. Praktische Durchführung und Interpretation der Befunde: Um das Vertrauensverhältnis nicht zu gefährden, darf ein Medikamenten-Screening nur nach Aufklärung und mit Zustimmung des Patienten erfolgen. Die Untersuchung von Urin bietet sich als gering invasives Verfahren und wegen der Reservoirfunktion des Urins vorrangig an. Bei der Formulierung der Anforderungen und Interpretation der Befunde ist ein enger Kontakt zwischen Labor und dem Kliniker notwendig, damit – wie beispielhaft verdeutlicht wird – Fehlinterpretationen durch Kreuzreaktionen verschiedener Substanzen oder zu hohe Nachweisgrenzen vermieden werden. Die erhobenen Befunde sollten in erster Linie der Gütekontrolle der Therapie und nicht einer Bewertung des Patienten dienen. Folgerungen: Auch wenn der Stellenwert von Urinuntersuchungen oder anderer Verfahren eines Medikamenten-Screenings bisher nicht durch prospektive Untersuchungen belegbar ist, erscheint es als wichtiges Werkzeug in der Therapie chronischer Schmerzen, mit dem jeder Therapeut vertraut sein sollte.SummaryIntroduction: Drug therapy plays often an important role in the treatment of chronic pain. Former studies and also experiences of clinical practice have given evidence, that insufficient patient compliance is a widespread event. Therefore drug screening becomes a significant tool for quality assurance. In the following the methodical and practical aspects of drug screening are described and recommendations for its use in clinical practice are suggested. Objective of drug screening: This tool can be used to check the intake of prescribed drugs, to detect hidden taken drugs, to decide whether side effects result of the prescribed medication or not and to support a withdrawal therapy. Practical basics and interpretation of the findings: Drug screening presupposes an informed patient, who consents to the investigation. Otherwise confidence is risked and the handling with unexpected results is not possible any more. Testing of urine has the advantage of a non invasive procedure and makes use of the reservoir of the bladder. A close co-operation and good communication between therapist and laboratory prevents misinterpretations, which might result from inaccurate formulated questions or methodical limitations, for instance because of cross reacting substances or a too insensitive detection level for the respective drug. The finding must primary bee used to value the therapy and improve the compliance but can not prove the patient himself. Conclusions: Even if the value of drug screening is not prospectively investigated until now, clinical experiences reveals it is as powerful tool for monitoring effectiveness and side effects of pharmacotherapy of pain and also of patient compliance which the prescribed drug regimes.