Methadone toxicity in infants: a report of two fatalities

The Role of Risk or Contributory Death Factors in Methadone-Related Fatalities: A Review and Pooled Analysis

Methadone-related deaths are characterized by a wide range of post-mortem blood concentrations, due to the high pharmacokinetic/dynamic inter-individual variability, the potential subjective tolerance state and to other risk factors or comorbidities, which might enhance methadone acute toxicity. In the present study, the association among pre-existing and external conditions and diseases and the resultant methadone death capacity have been investigated. Beside a systematic literature review, a retrospective case-control study was done, dividing cases in which methadone was the only cause of death (controls), and those with associated clinical-circumstantial (naive/non-tolerant state), pathological (pulmonary or cardiovascular diseases) or toxicological (other drugs detected) conditions. Methadone concentrations were compared between the two groups and the association with conditions/diseases was assessed by multiple linear and binomial logistic regressions. Literature cases were 139, in house 35, consisting of 22 controls and 152 cases with associated conditions/diseases. Mean methadone concentrations were 2122 ng/mL and 715 ng/mL in controls and cases respectively, with a statistically significant difference (p < 0.05). Lower methadone concentrations (by 24, 19 and 33% respectively) were detected in association with naive/non-tolerant state, pulmonary diseases and presence of other drugs, and low levels of methadone (<600 ng/mL) might lead to death in the presence of the above conditions/diseases.

Increasing Methamphetamine Detection in Cases of Early Childhood Fatalities

Age and organ maturity can influence drug toxicity in children; however, most clinical data and literature are based on drug concentrations in adults. Therefore, the interpretation of drugs detected in children is often difficult or not possible. Retrospective reviewing of pathology and toxicology information from postmortem cases may assist in future interpretations or identify drug trends. A search of the Forensic Science SA case files was undertaken over 15 years from January 2002 to December 2016 for all children (<13 years). Of the 412 pediatric coronial cases, toxicological information was available on 373. At least one drug was detected in 94 cases with paracetamol, ibuprofen, codeine and hospital-administrated lignocaine and morphine among the most commonly detected agents. Methamphetamine, one of the most commonly abused illicit drugs in Australia, was found in seven cases. In the methamphetamine cases, deaths were associated with shared sleeping in three, pneumonia in one, and stillbirth in one. Methamphetamine was considered potentially contributory to death in two cases. The causes of death in the remaining two cases were undetermined. As six of the seven positive cases occurred in the 2012-2016 (n = 106) timeframe, an increase has occurred over recent years in the number of infants and young children presenting to forensic autopsy in South Australia who have detectable concentrations of methamphetamine. If this is an indication of a more generalized increased childhood exposure in the community there may be significant long-term physical and psychological effects.

Use of hair testing to determine methadone exposure in pediatric deaths

A case of death attributed to methadone acute poisoning in an infant aged 11 months is reported. A sudden infant death syndrome (SIDS) was suspected, whereas a traumatic cause of death was excluded regarding autopsy findings. Specimens were submitted to a large toxicological analysis, which included ethanol measurement by HS-GC-FID, a targeted screening for drugs of abuse and various prescription drug classes followed by quantification using UPLC-MS/MS methods. Methadone and its metabolite (EDDP) were detected in all the tested fluids, as well as in hair, with a blood concentration of methadone considered as lethal for children (73 ng/mL). The cause of death was determined to be acute "methadone poisoning", and the manner of death was "accidental". A discussion of the case circumstances, the difficulties with the interpretation of toxicological findings in children (blood concentration and hair testing), and the origin of exposure are discussed.

Opioid Related Deaths of Infants and Young Children

The prevalence of the opioid drugs is increasing worldwide. Greater access in turn increases the risk of infants and young children being exposed to potentially fatal concentrations of these drugs, either by accident or through the negligent or deliberate actions of a caregiver. This report reviews opioid-related fatalities in this population and discusses homicidal and accidental poisonings and the possible routes of exposure, including through breastfeeding. As with adults, autopsy findings in fatal pediatric opioid toxicity are nonspecific and such cases may mimic death from natural diseases such as metabolic disorders or channelopathies. A detailed review of the case history together with a complete autopsy and toxicology testing are essential for the correct certification of these deaths. Further challenges arise from the fact that toxic ranges for opioids are not well-defined in the pediatric population, and the forensic pathologist must rely on case reports and small case series’ to assist in the determination of “how much is too much”. Resources such as the National Association of Medical Examiners Pediatric Toxicology Registry (NAME PedTox) continue to be of great value, but depend on the voluntary submission of case data from members. Emerging phar-macogenetic data are revealing genetic variations associated with altered metabolism and tissue distribution of opioids; therefore, molecular autopsy techniques should be considered in these challenging cases, especially where the manner of death is unclear.