Clinical Chemistry Podcast

Expert Q&A

In the era of precision medicine, it is no surprise that there is an emerging interest in personalizing one's diet based on their genetic make-up. This concept called, "precision nutrition," refers to the application of -omics techniques such as genomics and metabolomics, to achieve better prevention or treatment of disease to optimize nutrition. The January 2017 Clinical Chemistry special issue on obesity includes a review article that summarizes the current and future roles of nutritional metabolomics.

Although bariatric surgery techniques were originally developed to treat morbid obesity, the indications for their use have expanded as a consequence of the emerging evidence of their wider metabolic benefits. Now described as metabolic surgeries, these treatment methods derive as much benefit from their metabolic and cardiovascular effects as from the resulting weight reduction. Though promising evidence is emerging, there is a need for further mechanistic studies to assess the true potential of metabolic surgery to treat the myriad other disorders of metabolism and to better understand their consequences in terms of cardiovascular disease and cancer risk reduction. Additionally, there may be unintended consequences of bariatric surgery that are related to long term adverse skeletal effects and nutritional deficiencies.

Hepatitis C virus or HCV infection affects close to 150 million people worldwide. In the U.S., it is estimated that as many as five million people have been infected with the Hepatitis C virus, many of whom are unaware of their infection. HCV is now the most common indication for liver transplantation, and it accounts for more deaths each year than all other reportable infectious diseases combined including HIV. Advances in testing methods and antiviral therapies with increased development of infrastructures that improve access care now make eradication of HCV infection in well-resourced countries a realistic goal. However, challenges in implementing screening programs and continues evolution of assay methods and screening protocols raise several issues for how clinicians and laboratories respond to the changing landscape for HCV diagnosis and treatment. The December 2017 issue of Clinical Chemistry includes a Q&A article with several experts who offer their insights and opinions on this topic.

Adrenal steroid analysis plays an important role in the diagnosis of Cushing's syndrome, disorders of steroidogenesis, and adrenal tumors. The analytical sensitivity and specificity for steroid assays have evolved over time from individual immunoassays to multiplexed mass spectrometry-based methods. This transition has highlighted a need for simultaneous measurement of multiple steroids and their various metabolites to achieve the best diagnostic accuracy. Therefore, metabolomic profiling performed by liquid chromatography, high-resolution accurate-mass mass spectrometry might be poised to make a substantial impact on endocrine laboratory testing. The December 2017 Issue of Clinical Chemistry describes such a method used to determine sex- and age-based reference intervals and to perform a limited assay evaluation in patients with different adrenal diseases.

Exposure to lead in adults is typically via occupational or environmental exposures. The incidence of lead poisoning have declined worldwide due to improved industrial safety measures and the limited use of lead in paint, pipes, and canned goods. Though an increasing number of lead intoxications have been caused by the use of contaminated illicit drugs, including opium, marijuana and amphetamine, this may be due to impurities introduced during manufacturing or from deliberate addition to increase the weight for a higher selling price. A Clinical Case Study in the December 2017 issue of Clinical Chemistry discusses a series of adult patients who presented with similar symptoms and were discovered to have extremely elevated blood lead concentrations.

Sepsis is a life-threatening condition associated with significant mortality and healthcare cost. There is increasing evidence supporting the use procalcitonin as a biomarker for diagnosis of bacterial sepsis and as a guide to discontinue antibiotic therapy. However, concerns about the efficacy, safety, and availability of procalcitonin exist. A Q&A article in the September 2017 issue of Clinical Chemistry asked experts with different roles in this field to share their thoughts on the challenges of procalcitonin-guided diagnosis and antibiotic therapy.

Richard Body

Randie Little