Metabolic screening panel

Today, many of the older methods used historically in clinical chemistry are being replaced by methods that utilize MS. In 2013, some areas of interest in clinical chemistry include steroid and vitamin D analyses that require a high selectivity and relative sensitivity. For example, the improved selectivity is essential in the analysis of testosterone in infants due to low concentrations. Immunoassays are not sufficiently selective to provide an accurate measurement of the true concentrations of these metabolites. There are many more assays being used or that are now in development in clinical chemistry, but a discussion of this growing use of metabolic screening is too broad and too evolutionary to be included here. Therefore, this chapter focuses on those proteins and metabolites (e.g., amino acids and acylcamitines) that are part of a classic newborn screening panel. 

Figure 6.2. Strategies for the design of decision trees for new compound evaluation. ADME-based screens can be incorporated in many places in a decision tree, three examples are illustrated A, ADME screens are run as a panel in parallel with early activity screens, compounds proceed to further biological screens after meeting set criteria B, ADME screens are run after a compound meets set potency criteria and compounds proceed to further biological screens after meeting set ADME criteria C, critical ADME screen (metabolic stability in this case) is run on compounds that meet potency criteria and then full ADME screen panel is run before compounds proceed.

Box 2.5 Case Example of a Metabolic Disorder Not Included on the Newborn Screening Panel... 

One would therefore think that aspartame is completely safe. There is, however, one exeeption About 1 in 10,000 people has a genetie disorder eaUed phenylketonuria that prevents them from metabolizing phenylalanine. The ensuing accumulation of the amino acid, detected by the presence of its metabohte phenylketone (see below ) in the urine, causes abnormalities in brain function. In developed countries, phenylketonuria is included in the newborn screening panel and dealt with by medieation and a strict dietary regimen. 

CBC with platelets, Basic Metabolic (electrolytes, BUN/creatinine, glucose) and Hepatic function Panel, PT (INR), PTT, ESR, fibrinogen. Blood for type and screen. 

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