Standardizzazione in enzimologia clinica: Una sfida per la teoria della riferibilità metrologica

The goal of standardization for measurements of catalytic concentrations of enzymes is to achieve comparable results in human samples, independent of the reagent kits, instruments, and laboratory where the assay is carried out. To pursue this objective, the IFCC has established reference measurement systems for the most important clinical enzymes. These systems are based on the following requirements: a) reference methods, well described in procedures that are extensively evaluated; b) suitable reference materials; and c) reference laboratories operating in a highly controlled manner. Using these reference systems appropriately, the diagnostic industry can assign traceable values to commercial calibrators. Clinical laboratories, which use routine procedures with validated calibrators to measure human specimens, can finally obtain values which are traceable to higher-order reference procedures. These reference systems constitute the structure of the traceability chain to which the routine methods can be linked via an appropriate calibration process, provided that they have a comparable specificity (i.e., they are measuring the same catalytic quantity).