High Yield Determinations
New research demonstrates an increased usefulness of hair toxicology testing for improving outcomes of child abuse cases over traditional urine toxicology testing.
by Joseph Salerno, MS
Stauffer, SL, Wood, SM, and Krasowski, MD. (2015). Diagnostic yield of hair and urine toxicology testing in potential child abuse cases. Journal of Forensic and Legal Medicine, 33: 61-67.
Recent research has demonstrated an increased efficacy of hair specimen toxicology testing over urine testing for improving outcomes for victims in child abuse cases. The retrospective chart review covering more than 10 years of data (January 2004 – April 2014) found that the clinical outcomes for children of abuse were improved in 86.5% of hair toxicology results that identified child drug exposure that could not be explained by legal medical administration of medications to the child. In contrast, clinical outcomes remained unchanged in all of the 457 urine screens conducted in the child abuse cases during this period. The study was published by researchers from the Department of Pathology at the University of Iowa Hospitals and Clinics, Iowa City, IA.
In 2012, 678,810 substantiated cases of child abuse were reported by the US Department of Health and Human Services. 1,593 of those cases were ultimately fatal for the child. The risk of harm to a child increases dramatically if the person in charge of the welfare of the child is intoxicated (alcohol or drugs), experiencing drug withdrawal, or pursuing the acquisition of drugs. In many cases of suspected child abuse, the detection of drug biomarkers in child specimens such as hair or urine may be the first objective finding that can be reported in the case.
Stauffer et al’s research suggests that the choice of testing has a potentially high impact on the ultimate welfare of the child. Their study focused on 457 child abuse cases in which both hair and urine toxicology testing were simultaneously conducted.
Notably, the results of this study indicated that urine toxicology testing had little efficacy for identifying actionable drug results. Urine screening was able to identify actionable illegal drug exposure less than 5% of the time, with more than 95% of positive results explainable by documented legal administration of medications to the child, predominately opiate pain relievers and benzodiazepines.
Hair toxicology testing was able to identify illegal drug exposure in 77.4% of cases with positive drug testing results. Hair testing most often identified cocaine, cannabinoid, and amphetamine exposure, in that order of frequency.
Interestingly, in 64% of hair testing positives, the parent drug compound was identified in absence of the metaboloite of the native drug. This pattern of testing results is consistent with a scenario of significant environmental exposure of the child, where a child has been placed in a potentially harmful situation by their caregivers.