Mass spectrometry in clinical diagnosis

Posted by Doctor Pham Anh Tuan - Vinmec Stem Cell Research Institute and Gene Technology

Mass Spectrometry (MS) is a technique for measuring the mass to charge-m/z ratio of ions. From the results of that mass and structure, we can know about the biological function of the analyzed molecule. Tandem Mass Spectrometry (MS/MS) also shows chemical components at low or even very low concentrations in the analytical mixture.
Currently, there are fewer mass spectrometry-based diagnostic methods included in clinical routines compared with traditional analytical systems, immunohistochemistry. However, the use of mass spectrometry in clinical diagnosis has increased in recent years. Clinical applications of mass spectrometry include: screening and target analysis, where screening aims to detect biomarkers for disease, toxicology, and pharmaceuticals. In addition, the accuracy, sensitivity and assurance of the results are specific to the target quantitative analyses.

Newborn screening of inborn errors of metabolism (NBS-IEM) is defined as a complete system that includes training; screening; monitor, test and confirm abnormal results; diagnose; treatment; evaluate the effectiveness. OMIN has data on 6,000 genetic diseases in humans, whose genetic disorders must be treated to ease symptoms or protect against the effects of the disease. Newborn screening is appropriate for individuals, families, and society as a whole, as long as screening is started early. And MS/MS has become an important and popular technique in newborn screening for congenital metabolic defects in many advanced countries around the world (Table 1):

The advantage of MS/MS can be, for example, that from an analysis of dried blood spots more than 40 substances can be precisely quantified, this gives the clinician a more complete patient profile. in a short time, and at the same time, low cost of chemicals is also an advantage. Many disorders that cannot be completely treated are included in the neonatal screening panels identified by MS/MS. Compared with other methods, MS/MS is strongly effective in screening analysis of diseases with high frequency (such as medium chain acyl CoA dehydrogenase-MCAD deficiency disease). However, disease screening becomes difficult when there are similar biomarkers for more than one disease (such as C5-hydroxyacylcarnitine-C5OH, which is an indicator for both holocarboxylase deficiency and 3-methylcrotonyl enzyme deficiency. -CoA carboxylase.

MS is also used to analyze and detect new biomarkers for autoimmune diseases, cardiovascular diseases and severe acute respiratory distress syndrome (SARS) or endocrine disorders in women and children.
We all know, vitamin D deficiency will lead to bone disorders as well as other diseases. There are different methods to determine the serum vitamin D concentration, usually by quantification of 25-hydroxyvitamin and the results are always elevated in clinical laboratories. Until recently, this increased parameter was evaluated by immunoassay, but it failed to distinguish 25-hydroxyvitamin D2 and D3. Through Liquid Chromatography-LC-MS/MS, it is now possible to easily distinguish these two substances, thus making diagnosis more efficient with sensitivity. high.
References
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