March 2012 CFTN

An AACC/CAP Educational Newsletter for Toxicology Laboratories

Read the March 2012 Issue

Oral Fluid Recommended for Use as Drug-Testing Matrix
By Christine Moore
In 2011, the Drug Testing Advisory Board of the Substance Abuse and Mental Health Services Administration recommended that oral fluid be allowed as a specimen in federal workplace drug-testing programs. The board had considered oral fluid samples previously, but turned them down because of disadvantages such as inadequate volume for analysis, drug absorption by collection pads, inability to create split samples, and concerns with marijuana analysis. The new recommendation is a recognition that technology has largely overcome these problems.

After reading this article, the reader will be able to:

  • List the advantages and drawbacks of using oral fluid as a specimen to detect drug use.
  • Describe the immunoassays that are available for use in oral fluid drug screening.
  • Describe the confirmation methods used in oral fluid drug testing. Discuss the principles that are involved in the interpretation of the results of oral fluid drug testing.

Dried Blood Spot Analysis Spreads to More Applications
By Ann-Sofie M.E. Ingels, Willy E. Lambert, and Christophe P. Stove
A dried blood spot (DBS) is capillary whole blood obtained by a finger or heel prick and collected on filter paper. DBS sampling has generally been used for newborn screening; however, it has recently received interest for use in therapeutic drug monitoring (TDM), clinical and preclinical studies, pharmacokinetics, and toxicology (1).

After reading this article, the reader will be able to:

  • Describe the advantages and drawbacks of dried blood spot sampling for drug detection.
  • Discuss the advantages of direct derivatization of the dried blood spot for drug detection.

Ethylene Glycol Continues to Pose Threat of Poisoning
By Donald L. Frederick
Ethylene glycol poisoning continues to cause medical emergencies and claim lives worldwide despite the dissemination of information to the public about its toxicity. Although ingestion can have serious medical consequences, with early recognition the prognosis of treated patients is excellent. The most common source of ethylene glycol is commercial antifreeze solutions.

After reading this article, the reader will be able to:

  • Describe the metabolism and pharmacokinetics of ethylene glycol.
  • Summarize the four clinical stages following ethylene glycol ingestion.
  • Describe the treatment options for patient presenting to the emergency department with ethylene glycol ingestion.
  • Describe how the laboratory can support the diagnosis and treatment of ethylene glycol ingestions.

CAP Offers New Prociency Surveys and Added Analytes
The College of American Pathologists is offering four new proficiency testing surveys for toxicology and therapeutic drug monitoring and is adding several new analytes to its existing surveys.

Earning ACCENT Credit
Clinical & Forensic Toxicology News readers can receive 4.0 ACCENT® continuing education credit hours per year (one credit per quarterly issue).