To test or not to test? That is the dilemma that clinical laboratories are faced with when it comes to testing off-label specimen types. Most testing offered in clinical labs is Food and Drug Administration (FDA)-approved and validated for use with serum, plasma, and urine. However, clinical laboratories often receive requests to perform routine testing on body fluid types that are not listed in the intended use section of the assay manufacturer’s package insert, such as pleural or synovial fluids. Regulatory agencies have recently begun to classify these alternate body fluid sources as unique specimen types, appreciating that differing chemical compositions may impact assay performance. Due to the large patient safety implications, laboratories performing off-label testing are under increased scrutiny by regulatory agencies, especially in light of FDA’s draft guidance on laboratory-developed tests.

In today’s regulatory climate, complete method validation of alternate specimen types is expected by accrediting bodies (e.g. CAP, COLA, ISO 15189). Although most laboratorians are familiar with the method validation process, the added complexity that accompanies these alternate matrices can be daunting. With increased regulatory requirements and limited guidance available for how to accomplish this task, laboratorians are searching for insights into how to properly validate alternate sample types for clinical use that minimize patient risk and maximize the diagnostic value.

In a short course this afternoon, “Analytical Challenges and Clinical Controversies in Body Fluid Testing,” Darci Block, PhD, and Sutirtha Chakraborty, MD, will discuss some of the current issues in laboratory testing surrounding off-label body fluids as well as effective strategies to overcome them. Block, co-author of the Quick Guide to Body Fluid Testing (Block and Franke, 2015 AACC Press), will provide guidance for the analytical validation of off-label body fluid types for clinical use. She will discuss practical approaches to the challenges that every lab faces when tackling body fluid validations, including assessment of clinical utility for better patient care. Chakraborty will follow with practical tips on how to standardize reporting and ensure proper clinical interpretation of body fluid chemistry.

The interactive session will use real-life clinical case studies and testing scenarios to highlight specific body fluid testing issues and diagnostic dilemmas. Participants will be provided with instructional tools to appropriately evaluate the current state of body fluid testing in their lab and to identify areas needing improvement. The speakers will also present their perspectives on how the lab can consult and partner with clinicians to optimize test selection and interpretation of body fluid analytes. This session is highly recommended if your lab currently performs off-label testing of alternate body fluid types or is considering it.