What Happened?

A study examining a new blood-based pregnancy (hCG) test from NOW Diagnostics was just published in September’s issue of the Journal of Applied Laboratory Medicine (JALM).  The JALM is an AACC (American Association for Clinical Chemistry) publication and is read by thousands of professionals in the clinical chemistry space and healthcare arena.

Where Was the Study?

The study was conducted by the prestigious Department of Pathology and Laboratory Medicine at the University of California, Los Angeles (UCLA) and published this month.  The study examined a new blood-based hCG (pregnancy) test’s validity as a viable alternative to current testing methods and as a way to improve patient care.

What Was Done?

UCLA tested 283 samples.  First, they tested the samples for pregnancy using NOW Diagnostics’ whole blood, point-of-care pregnancy test, the ADEXUSDx® hCG test.

Next, UCLA tested the same patient samples on a lab analyzer.  In this case, quantitative total hCG values were obtained from the RochehCG+β2 sandwich assay.  The goal was to assess if the new point-of-care test (POCT) could obtain comparable results to the lab analyzer.

Why Compare the ADEXUSDx® hCG test  to a Lab Analyzer?

Lab analyzers have been the gold standard of care for diagnostic tests historically.  Proving that a point-of-care test (POCT) can provide comparable results to a lab test would make it easier and more accessible to obtain the most sensitive, accurate results possible when diagnosing pregnancy.  This becomes particularly important in early pregnancy when a treatment could potentially be harmful or fatal to a developing fetus. Quoting directly from the UCLA white paper:

” The test would offer improved turnaround time without sacrificing sensitivity or specificity as compared with a laboratory based immunoassay, which typically has an overnight turnaround time at our institution… In addition, the ADEXUSDx hCG test represents a valuable and unprecedented alternative to a laboratory-based assay in settings where diagnostic and laboratory services are unavailable.”

Why Test for Pregnancy with Blood Instead of Urine?

You may wonder, “What’s wrong with urine tests?”  They’ve certainly been around for decades.  Simply put, urine just isn’t as accurate as blood.  Here’s a rundown of the top reasons why urine tests are facing more criticism in the field, and see this post for more on urine vs. blood pregnancy tests.

Urine tests are facing increasing criticism as they are proving to be more susceptible to false negative results because:

  • Urine tests aren’t as sensitive (higher limit of detection)
  • Urine can become diluted
  • Urine works best when tested in the morning when hCG levels tend to be the strongest
  • Something called beta core fragment can cause false negatives in urine tests
  • Something called “the hook effect” can occur when hCG levels become extremely high and the test becomes “overwhelmed,” which can cause a false result

Here’s the Impact Statement taken directly from the study:

“The NOWDiagnostics’ ADEXUSDx™ point-of-care (POC) tool is a rapid, Food and Drug Administration cleared, POC human chorionic gonadotropin (hCG) assay that accurately and rapidly (10min) identified hCG-positive blood samples >10mIU/mL. The use of blood instead of urine, the decreased time to diagnosis, and the improved lower limit of detection (10vs20mIU/mL) are key factors that could translate to improved clinical outcomes associated with missed or delayed diagnosis. The ease of use and added sensitivity could lead to improved healthcare delivery to women of child-bearing age, particularly in resource-limited settings.”

Want to Know More?

The full press release can be found here.

The study is published in JALM in September’s issue and can be purchased here.

As always, you can contact us at NOW Diagnostics anytime by clicking here.