Clinical Chemistry Podcast

More than 70 million couples worldwide are affected by infertility, with male-factor infertility accounting for about half of the cases. Semen analysis is critical for determining male fertility potential, but conventional testing is costly and complex. Here, we demonstrate a paper-based microfluidic approach to quantify male fertility potential, simultaneously measuring 3 critical semen parameters in 10 min: live and motile sperm concentrations and sperm motility.

Gestational diabetes mellitus (GDM) is associated with adverse pregnancy outcomes, but risk is reduced with identification and early treatment. Glucose measurements are affected by preanalytical sample handling, such as temperature of storage, phlebotomy–analysis interval, and use of a glycolysis inhibitor. We evaluated glucose concentrations and the incidence of GDM after strict implementation of the American Diabetes Association (ADA) preanalytical guidelines, compared with usual hospital conditions.

Evidence is accumulating that circulating 1,25-dihydroxyvitamin D [1,25(OH)2D] concentrations are inversely related to overall mortality.

Limited information is available about testosterone concentrations representative of the general US population, especially children, women, and non-Hispanic Asians.

Mass spectrometry–based in vitro diagnostic devices that measure proteins and peptides are underutilized in clinical practice, and none has been cleared or approved by the Food and Drug Administration (FDA) for marketing or for use in clinical trials. One way to increase their utilization is through enhanced interactions between the FDA and the clinical mass spectrometry community to improve the validation and regulatory review of these devices.

There are now numerous epidemiological studies that have demonstrated that low plasma concentrations of vitamin D are associated with not only bone related disorders, but with a wide variety of adverse health outcomes.

A driving force in the development of point-of-care diagnostics is to conveniently provide information without delay so that healthcare decisions can be made while the patient is on-site. Most point-of-care devices are based on immunochemical, electrochemicalor colorimetric techniques that can be miniaturized and made portable.

A mass spectrometer is a sensitive and specific instrument." In some form or another, this is often the label applied to the platform by all manner of professions (chemists, physicists, biologists, physicians, clinicians, and laboratorians, novice and expert alike). This is a view of mass spectrometry (MS) through rose-colored glasses. It should be properly said that MS can be sensitive and specific, but not without due consideration for the measurement to be performed. In clinical laboratories, this measurement is the extraction, detection, and often, quantification of a compound of interest from a biological matrix.

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.

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.

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.

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.

In the past decade there has been a rapid increase in the number of individuals who have had their entire genome sequenced. Over the next decade that number will go from the thousands to the millions. These people are having their genomes sequenced for research, recreational interest, and clinical testing.

Vitamin D insufficiency has been widely associated with numerous negative health outcomes, including higher all-cause mortality, although no mechanism has been formally established for such observations.

Clinical trials, epidemiologic and most types of clinical research, include the acquisition of biological samples to be analyzed either immediately after collection, or in the future for biomarkers related to the study hypotheses. Tested biomarkers include those used to monitor subjects' health and to detect harmful side effects or to follow impact of therapeutic interventions.

Biomarkers are playing increasingly important roles in the detection and management of patients with cancer. Despite an enormous number of publications on cancer biomarkers, few of these biomarkers are in widespread clinical use.

Biomarkers are playing increasingly important roles in the detection and management of patients with cancer. Despite an enormous number of publications on cancer biomarkers, few of these biomarkers are in widespread clinical use.

A major objective of the International Federation of Clinical Chemistry and Laboratory Medicine, or IFCC, Task Force on implementation of Hemoglobin A1c Standardization is to develop quality targets with the measurement of Hemoglobin A1c.

Medical laboratories provide valuable services to aid in patient diagnosis and management, but systematic evidence of laboratory medicine's specific contribution to the overall process of healthcare is not easy to come by. Even the widely quoted claim that laboratory medicine results are responsible for a 70% of all clinical decisions seems to elude objective verification.

Over the past 20 years or so there have been several studies published showing an association between decreased concentrations of vitamin D in blood and the risks of cardiovascular disease, stroke, cancer, fractures, even overall mortality.

Rapid urine pregnancy tests have been available for over 30 years. They can be performed in minutes and are used at home, in doctors' offices and in emergency rooms. Doctors in particular rely on these tests to rule out pregnancy in order to prevent fetal injury or death that could be caused by certain medical procedures or drugs.

Recently, the New England Journal of Medicine partnered with Area9 Learning, a physician-led pioneer in adaptive learning, to create a platform with smart technology that adapts to clinicians' learning goals and knowledge gaps to deliver the information they need to know.

Aggressive strategies to lower Low Density Lipoprotein cholesterol in circulation are recommended for prevention of cardiovascular events. Most often laboratories report LDL-cholesterol based on an equation using measured values of total cholesterol, HDL - cholesterol and triglycerides, the so called Friedewald calculation named after the first author who published that work in Clinical Chemistry back in 1972.

Medical laboratories frequently encounter clinically unexpected results that require timely clinical evaluation because they may indicate an imminent life-threatening condition or a major clinical deterioration. Laboratories, therefore, need to identify and report such results sooner than they normally would, and have policies and procedures that minimize the possibility of patient harm due to delayed clinical attention. The concept of these so-called "panic values" was raised by George Lundberg in 1970, but a variety of other terms have since appeared in the literature. For example, urgent, critical, acute, alert, abnormal, markedly or significantly abnormal, clinically significant, vital, red or orange or yellow zone values, and various combinations of terms.

In December 2013 the genetics laboratory 23andMe stopped marketing direct-to-consumer disease predictive genetic testing in order to comply with a directive from the US Food and Drug Administration. The FDA's action was intended to protect the American public from questionable disease risk predictions.

Big data now seems to be everywhere. Google search queries are used to predict flu outbreaks and airline statistics or mined to determine the best hour of which day to book plane tickets. Clinical laboratories can also benefit from these trends. Given the emerging importance of reproducible data analysis pipelines, one could think of a special group of trained big data experts that could be available to regulatory agencies and to clinical laboratories for review and auditing of their processes and practices, and who may be able to offer suggestions for improvements.