False negative result for amphetamines on the Triage® Drug of Abuse panel?: The cause of the unusual phenomenon with experimental analyses

Fatal acute lemborexant Poisoning: An autopsy case report

A 50-year-old male was found dead in a park. Postmortem analysis using liquid chromatography-tandem mass spectrometry revealed lemborexant concentrations of 1.651 μg/mL in blood from the right heart, 0.236 μg/mL in the urine, and 58.642 μg/mL in the stomach contents. Based on the autopsy findings and postmortem analyses, the cause of death was identified as acute lemborexant poisoning due to an overdose. Although lemborexant is generally considered safe, its excessive ingestion can be fatal. Since no lethal concentration of lemborexant has been reported, the blood levels in this case can serve as a reference. Despite its widespread clinical use, lemborexant is not detected by the rapid urine drug screening tests currently available in Japanese investigative agencies. Forensic pathologists must be vigilant in order not to overlook acute lemborexant poisoning.

Applicability of a Chemiluminescence Immunoassay to Screen Postmortem Bile Specimens and Its Agreement with Confirmation Analysis

Bile has emerged as an alternative matrix for toxicological investigation of drugs in suspected forensic cases of overdose in adults and intoxications in children. Toxicological investigation consists in screening and, subsequently, confirming the result with specific techniques, such as liquid chromatography with tandem mass spectrometry (LC-MS/MS). As there is no screening test on the market to test postmortem bile specimens, the novelty of this study was in investigating the applicability of a chemiluminescence immunoassay, designed for other matrices and available on the market, on bile and validate its use, testing the agreement with LC-MS/MS analysis. Bile specimens were obtained from 25 forensic cases of suspected death from overdose and intoxication. Sample preparation for bile screening consists simply in centrifugation and dilution. Confirmation analysis allows simultaneous identification of 108 drugs and was validated on bile. Kappa analysis assessed a perfect agreement (0.81-1) between the assays for benzodiazepines, methadone, opiates, cocaine, oxycodone, cannabinoids, buprenorphine and pregabalin; a substantial agreement (0.41-0.6) was reported for barbiturates. No agreement was assessed for amphetamines, due to an abundance of putrefactive amines in postmortem specimens. In conclusion, this fast and easy immunoassay could be used for initial screening of bile specimens, identifying presence of drugs, except amphetamines, with reliability.

Assessment of Triage DOA®, Status DS10, and DRIVEN-FLOW® M8-Z on-site drug screening kits for postmortem urine

Based on the screening results of mass analyses using gas chromatography- mass spectrometry (GC-MS) and liquid chromatograph-tandem mass spectrometry (LC-MS/MS), we assessed the performance of Status DS10 (Status) and DRIVEN-FLOW® M8-Z (DF8), and compared the results with those of Triage DOA® (Triage) using 356 autopsy urine samples within one month of death. The sensitivity to benzodiazepines was 0.52 in Triage, 0.59 in Status, and 0.58 in DF8 with few false-positive cases. Triage detected triazolo-derivatives more easily than DF8. DF8 detected diazepam and nitro-benzodiazepines more easily than Status and Triage, with Status performing better than Triage. However, lorazepam detection with Status was difficult. There were 11 false-positive cases for amphetamines in Triage and 12 for Status-AMP at more than one week after death, but there were no false-positive in Status-MET and DF8. Tricyclic antidepressant (TCA) was detected in five cases by mass analysis, while there were 6 false-positive cases in Triage and 10 in both Status and DF8. In the TCA false-positive cases, tricyclic psychotics such as quetiapine, chlorpromazine, and carbamazepine existed. There were 23 true-positive and 6 false-positive cases for zolpidem in DF8 without false-negative cases. The accuracy of Status and DF8 for barbiturates or opiates was almost 1, but Triage was 0.98. There were no samples containing cocaine, THC, phencyclidine, or methadone. Based on the above, we conclude that Status and DF8 are comparable or slightly better than Triage, with fewer false-positive and fewer false-negative cases, except for TCA.

Efficacy of DRIVEN-FLOW® M7-II, a new on-site drug screening kit in postmortem urine compared with Triage DOA®

The efficacy of DRIVEN-FLOW® M7-II(DFM7II) for seven drug groups was compared with Triage DOA® (Triage) using 340 autopsy urine samples taken from bodies within 1 month of death based on mass screening analysis of GC/MS and LC-MS/MS. The sensitivity to benzodiazepines was 0.56 in Triage and 0.53 in DFM7II with few false positives, and their accuracy was 0.88. Triage detected triazolo diazepine derivatives more easily than DFM7II. DFM7II detected diazepam and nitro benzodiazepines more easily than Triage. There were nine amphetamine false-positive cases of more than 10 days after death in Triage, but these were absent in DFM7II during this period. The accuracy of amphetamines for Triage was 0.96 and for DFM7II was 1. Tricyclic antidepressant (TCA) was detected in five cases by mass analysis, while there were four false-positive cases using Triage and eight cases using DFM7II. In the TCA false-positive cases of both kits, tricyclic psychotics such as chlorpromazine, carbamazepine, and quetiapine were included as well as the drug poisoning cases. There were no samples containing cocaine or THC. The accuracy of DFM7II for opiate and barbiturates was 1, but those of Triage was less than 1. Based on the above, DFM7II is a more accurate kit with fewer false-positives for target drug groups, other than TCA, than Triage.

Triage DOA® versus INSTANT-VIEW M-1® in Urinary Drug Screening for Acute Drug Poisoning: A Prospective Cross-sectional Study

Objective In the management of patients with suspected acute drug poisoning, a screening test using the patient's urine is usually performed. The Triage DOA^® and INSTANT-VIEW M-1^® kits are two commonly used point-of-care screening kits in Japan. However, the relationship between the results of these screening kits and the blood concentration of the poisoning drug is not clear. In this study, we evaluated which kit is more useful for acute drug poisoning screening based on a comparison of their results with the results of a serum drug analysis. Methods This prospective cross-sectional study investigated all patients with acute drug poisoning admitted to a general hospital in Tokyo, Japan, over a nine-month period. The Triage DOA^® and INSTANT-VIEW M-1^® screening kits were used, and a qualitative serum analysis was conducted simultaneously in all cases. We compared the kits for use in screening patients with acute drug poisoning and evaluated the utility of the kits. Results For the 117 patients enrolled in this study, the 2 kits showed different sensitivities to benzodiazepines (Triage^®, 78.6%; INSTANT-VIEW^®, 90.5%). Both kits showed high sensitivity to barbiturates (Triage^®, 87.0%; INSTANT-VIEW^®, 91.3%) but low sensitivity to tricyclic antidepressants (Triage^®, 25.0%; INSTANT-VIEW^®, 45.8%). Conclusion Because the sensitivity varies depending on the kind of drug, it is difficult to discuss the superiority of these kits. However, this study compared the results of two types of urinary drug screening kits with the results of qualitative analysis of drugs in serum as a gold standard, providing important reference data.

‘False-positive’ and ‘false-negative’ test results in clinical urine drug testing

The terms ‘false-positive’ and ‘false-negative’ are widely used in discussions of urine drug test (UDT) results. These terms are inadequate because they are used in different ways by physicians and laboratory professionals and they are too narrow to encompass the larger universe of potentially misleading, inappropriate and unexpected drug test results. This larger universe, while not solely comprised of technically ‘true’ or ‘false’ positive or negative test results, presents comparable interpretive challenges with corresponding clinical implications. In this review, we propose the terms ‘potentially inappropriate’ positive or negative test results in reference to UDT results that are ambiguous or unexpected and subject to misinterpretation. Causes of potentially inappropriate positive UDT results include in vivo metabolic conversions of a drug, exposure to nonillicit sources of a drug and laboratory error. Causes of potentially inappropriate negative UDT results include limited assay specificity, absence of drug in the urine, presence of drug in the urine, but below established assay cutoff, specimen manipulation and laboratory error. Clinical UDT interpretation is a complicated task requiring knowledge of recent prescription, over-the-counter and herbal drug administration, drug metabolism and analytical sensitivities and specificities.