Clinical Chemistry Podcast

Protein glycosylation is increasingly recognized as a crucial modulator of protein function, offering a third layer of biological information over genomics and proteomics. Modern tools for analyzing released N-glycans from cells and body fluids, i.e., the glycome, have shown abnormal protein glycosylation in numerous human diseases. These include both genetic and acquired diseases, ranging from diabetes, cancer, and inflammatory disease to neurodegenerative and neuromuscular disease. Insights from this novel field in human medicine provide exciting perspectives toward understanding disease processes, identifying therapeutic targets, and designing individualized diagnostics based on protein concentrations and glycosylation status. However, the main question is how we can translate this information into concrete biomarkers in a clinical diagnostic setting, with high demands on technical robustness and the ability to interpret results within specific patient groups.

Despite increasing prevalence of novel psychoactive substances, no human metabolism data are currently available, complicating laboratory documentation of intake in urine samples and assessment of the drugs' pharmacodynamic, pharmacokinetic, and toxicological properties. In 2014, THJ-018 and THJ-2201, synthetic cannabinoid indazole analogs of JWH-018 and AM-2201, were identified, with the National Forensic Laboratory Information System containing 220 THJ-2201 reports. Because of numerous adverse events, the Drug Enforcement Administration listed THJ-2201 as Schedule I in January 2015.

Analytically sensitive techniques for measuring minimal residual disease (MRD) in multiple myeloma (MM) currently require invasive and costly bone marrow aspiration. These methods include immunohistochemistry (IHC), flow cytometry, quantitative PCR, and next-generation sequencing. An ideal MM MRD test would be a serum-based test sensitive enough to detect low concentrations of Ig secreted from multifocal lesions.

The Kidney Disease Improving Global Outcomes (KDIGO) guideline recommends use of a cystatin C–based estimated glomerular filtration rate (eGFR) to confirm creatinine-based eGFR between 45 and 59 mL · min−1 · (1.73 m2)−1. Prior studies have demonstrated that comorbidities such as solid-organ transplant strongly influence the relationship between measured GFR, creatinine, and cystatin C. Our objective was to evaluate the performance of cystatin C–based eGFR equations compared with creatinine-based eGFR and measured GFR across different clinical presentations.

Informatics is changing the processes behind laboratory medicine. With ever-growing demands on laboratory medicine professionals not only to collect and interpret omics data in the era of the Precision Medicine Initiative, but also to ensure high-quality, low-cost patient management in the structure of accountable care organizations, we have invited several experts to discuss their take on "big data."

Combined testing of high-sensitivity cardiac troponin T (hs-cTnT) and copeptin at presentation provides a very high—although still imperfect—negative predictive value (NPV) for the early rule-out of acute myocardial infarction (AMI). We hypothesized that a second copeptin measurement at 1 h might further increase the NPV.

We investigated whether obese pregnant women negative for gestational diabetes (GDM) still experience dysglycemia, as indicated by high glycated hemoglobin (Hb A1c) at delivery, and whether this impacts offspring and long-term maternal outcomes.

STARD 2015: An updated list of essential items for reporting diagnostic accuracy studies

Increased concentrations of non-fasting remnant cholesterol are thought to be atherogenic in thesame way as LDL cholesterol,by transport into andaccumulationof lipid into the arterial wall.

For patients with acute coronary syndrome who have undergone interventions such as placement of a stent, it has become standard practice to treat them with a combination of aspirin and opidogrel to prevent subsequent thrombotic events; however, clopidogrel is a drug that requires activation by a liver enzyme, CYP2C19.

Most of us are familiar with the link between elevated concentrations of lipids in our blood and an increased risk for cardiovascular disease which is responsible for about 500,000 deaths each year in the United States. It has been common practice to measure those lipids only after a period of fasting. This practice was put in place because of the known increases in triglycerides that can occur after eating; however, fasting lipid profiles have not actually been shown to be superior to nonfasting lipid profiles in assessing the risk for cardiovascular disease.

Microfluidics has attracted a lot of attention across a wide range of disciplines because of the potential for using it to analyze tiny samples and to integrate processes onto handheld Labs-on-a-Chip. So instead of sending vials of blood to a central laboratory and getting results back days later, you can imagine a Microfluidic device that can give you the same performance, but with a finger prick of blood right on the spot, in minutes.

Commutability is an important concept in determining traceability and relationship among different methods used to measure the same analyte, but how to delineate commutable materials is not straightforward and a number of techniques have been proposed.

Several studies have suggested that prevention of atherosclerosis should begin in childhood as dyslipidemia in children is associated with severity of atherosclerotic lesions later in life. Pediatric lipid screening aims to identify children and adolescents with dyslipidemia, including both those with more severe genetic cases and those cases with mild to moderate lipid elevation due to secondary causes.

Advances in clinical laboratory testing have had a profound impact in improving the quality of medical care. Today laboratory diagnostic tests inform physicians and patients of the exact causes of a number of diseases and disorders, including cancer, chronic diseases, infectious diseases, sexually transmitted diseases, and genetic disorders.