Clinical Chemistry

July 2024—Instruments, assays, patient flow, and IT were some of what laboratory directors and IVD company representatives spoke of when CAP TODAY publisher Bob McGonnagle convened the group online on May 3. Here’s what they said about what instruments and assays are deployed where and the considerations that come into play in large health systems.

May 2024—In a time of wellness testing and high rates of levothyroxine prescribing for hypothyroidism, it may also be time to rethink TSH test result interpretation.

March 2024—For patients with type 2 diabetes, the cardiac biomarkers are a better predictor of early-stage heart failure than conventional risk prediction scores. “We need to use biomarkers,” says Petr Jarolim, MD, PhD.

March 2024—For urine toxicology screening, immunoassays are automated and rapid but have variable sensitivity and specificity and results are considered presumptive. Mass spectrometry, used for confirmation, has superior sensitivity and specificity but is labor-intensive and slow and requires significant expertise.

February 2024—Xylazine prevalence, lab-developed testing, and new technology are converging at Yale New Haven Health in a way that gives rise to questions, worry, and new hope for faster drug testing.

December 2023—The third and latest edition of recommendations for laboratory analysis in diagnosing and managing diabetes mellitus, released this summer, provide guidance on, among other things, ketone testing, glycolysis, and point-of-care testing. The last such recommendations were published in 2011.

November 2023—Glycated albumin and fructosamine are highly specific, with high levels suggesting hyperglycemia. This points to their utility in monitoring glycemic control in people with diabetes. “They’re quite useful in the setting of overt hyperglycemia,” said Elizabeth Selvin, PhD, MPH, at this year’s meeting of the Association for Diagnostics and Laboratory Medicine.

July 2023—As she surveys the opioid epidemic in North America, Christine Snozek, PhD, D(ABCC), could be tempted to think that a ripped-from-the-headlines reality has landed in clinical laboratories as well as on TV crime dramas. With the number of opioid-related deaths increasing in recent years, particularly since the start of the pandemic, drug testing demands have increased for labs as well, says Dr. Snozek, codirector of clinical chemistry and support services and director of point of care and central processing at Mayo Clinic in Arizona. If only she could turn to the entertainment industry for a technology-based solution. “I wish we had CSI lab capabilities,” she says, referring to the long-running police procedural. “You could run a sample and find all the drugs known to man on one test. If they could go ahead and release that technology, that would be wonderful,” jokes Dr. Snozek. Given that laboratories are unlikely to take a meeting with network executives, Dr. Snozek and others in the field will have to look elsewhere.

May 2023—Of the five methods used to measure HbA1c—immunoassay, boronate affinity, enzymatic, capillary electrophoresis, and ion-exchange HPLC—only the latter two can alert the laboratory and physician to the presence of a suspected hemoglobin variant. Even so, there are reasons to be cautious.

December 2022—In toxicology testing, cross-reactive compounds, incomplete medical records, immunoassay performance, calibrator drift, and human error all play into unexpected positives.

November 2022—In cases of unexpected negative results in toxicology testing, avoid overinterpretation, know your assays and providers, and don’t put off definitive testing when it’s needed, though it’s not a panacea.

September 2022—Which biomarker for heart failure should be used—BNP or NT-proBNP—and does it matter? That’s the question Christopher W. Farnsworth, PhD, set out to answer in his “hot topic” talk (one of a trio) at the AACC meeting in July.

September 2022—A single high-sensitivity cardiac troponin T measurement below the limit of quantitation of 6 ng/L is a safe and rapid method to identify a substantial number of patients at low risk for acute myocardial injury and infarction, say the authors of a recently published study.

August 2022—Just as there is scant room in this world for pink “While You Were Out” notepads, paper checks, or the copying skills of Bartleby the Scrivener, laboratories would do well to leave manual result verification in the past.