A Difficult Challenge for the Clinical Laboratory: Accessing and Interpreting Manufacturer Cross-Reactivity Data for Immunoassays Used in Urine Drug Testing

Abstract As has been reported many times by the lay press, urine drug testing may pose some unique challenges. The clinical laboratory interested in industrial drug testing (typically known as employee drug testing) should be aware of the many challenges that may be brought on by the fact that the result may be contested in an adversarial proceeding. This is what makes the urine drug test a forensic test. It may be one piece of evidence or the only piece of evidence used in an adversarial proceeding that may decide on punitive or rehabilitative action against an employee. As a result, unique standards for governmental contract laboratories have been proposed from the National Institute on Drug Abuse, and special proficiency testing and accreditation procedures have been promoted by professional societies. These standards illustrate the sensitive nature of the results. Because the results are subject to adversarial proceedings, all parties concerned in the testing process should be aware of the legal issues surrounding urine drug testing. There are constitutional and statutory issues as well as tort issues such as negligence, defamation, invasion of privacy, battery, infliction of emotional distress, and others. Laboratories should be especially aware of these issues, since they may be brought in as a third-party defendant to a suit or brought in as a participant in gathering the evidence. The laboratory should also be aware of other legal ramifications such as chain of custody, expert testimony, and the acceptability of scientific evidence.

Download Full-text

Interpretation and Utility of Drug of Abuse Screening Immunoassays: Insights From Laboratory Drug Testing Proficiency Surveys

Archives of Pathology & Laboratory Medicine ◽

10.5858/arpa.2018-0562-cp ◽

2019 ◽

Vol 144 (2) ◽

pp. 177-184 ◽

Cited By ~ 2

Author(s):

Matthew D. Krasowski ◽

Gwendolyn A. McMillin ◽

Stacy E. F. Melanson ◽

Annabel Dizon ◽

Barbarajean Magnani ◽

...

Keyword(s):

Health Care Providers ◽

Drug Testing ◽

Cross Reactivity ◽

Prescription Drug Abuse ◽

Variable Cross ◽

Care Providers ◽

Synthetic Opioids ◽

Urine Drug Testing ◽

Urine Drug ◽

Abused Drugs

Context.— Urine drug testing is frequently ordered by health care providers. Immunoassays are widely used for drug testing, yet have potential limitations, including variable cross-reactivity. The last decade has seen worsening of a prescription drug abuse epidemic. Objective.— To use data from a College of American Pathologists proficiency testing survey, Urine Drug Testing, Screening, to determine and summarize the characteristics, performance, and limitations of immunoassays. Design.— Seven years of proficiency surveys were reviewed (2011–2017). Results.— Rapid growth was seen in participant volumes for specific immunoassays for synthetic opioids (eg, buprenorphine, fentanyl, oxycodone) and 3,4-methylenedioxymethamphetamine (“ecstasy”). Participant volumes remained high for immunoassays targeting less commonly abused drugs such as barbiturates and phencyclidine. For opiate immunoassays, the number of laboratories using a 2000 ng/mL positive cutoff remained stable, and an increasing number adopted a 100 ng/mL cutoff. Opiate and amphetamine immunoassays showed high variability in cross-reactivity for drugs other than the assay calibrator. Assays targeting a single drug or metabolite generally performed well on drug challenges. Conclusions.— Survey results indicate strong clinical interest in urine drug testing and some adoption of new assays. However, urine drug testing availability does not parallel prevailing patterns of drug prescribing and abuse patterns. In particular, specific immunoassays for synthetic opioids and a lower positive cutoff for opiate immunoassays may be underused, whereas immunoassays for barbiturates, methadone, propoxyphene, and phencyclidine may be overused. Laboratories are encouraged to review their test menu, cutoffs, and assay performance and adjust their test offerings based on clinical needs and technical capabilities.

Download Full-text

Implementation of Mathematical Models to Predict New Cannabis Use by Urine Drug Testing: It Is Time to Move Forward

Journal of Analytical Toxicology ◽

10.1093/jat/bkab037 ◽

2021 ◽

Author(s):

Torben Breindahl ◽

Andreas Kimergård ◽

Peter D C Leutscher ◽

Peter Hindersson

Keyword(s):

Mathematical Models ◽

Drug Testing ◽

Cannabis Use ◽

Urine Drug Testing ◽

Urine Drug

Download Full-text

Analytical and technical aspects of testing for drug abuse: confirmatory procedures.

Clinical Chemistry ◽

10.1093/clinchem/34.3.471 ◽

1988 ◽

Vol 34 (3) ◽

pp. 471-473 ◽

Cited By ~ 14

Author(s):

M A Peat

Keyword(s):

Drug Testing ◽

Analytical Procedure ◽

Gas Chromatography Mass Spectrometry ◽

Technical Aspects ◽

Governmental Agencies ◽

Accuracy And Precision ◽

Urine Drug Testing ◽

Urine Drug ◽

Chemical Technique ◽

Layer Chromatography

Abstract Many laboratories are now performing urine drug testing for employers, governmental agencies, and other institutions. It is now recognized that presumptive positive screening results have to be confirmed by an analytical procedure based on a different chemical technique with greater than or equal sensitivity to the screening test. Thin-layer chromatography has been widely used for this; however, it is relatively insensitive for certain drugs, and it cannot satisfy the accuracy and precision requirements needed to determine threshold concentrations reliably. Gas chromatography-mass spectrometry is able to satisfy these threshold requirements and has become the method of choice for confirming initial immunoassay results.

Download Full-text