State of standardization for determination of catalytic concentration of alkaline phosphatase as viewed by different programs of external quality control: Our view of the situation and its solution.

Česká verzia

Authors: P. Sedlák ¹; B. Friedecký ²; J. Kratochvíla ²; M. Budina ²
Authors place of work: Oddělení klinické biochemie, Městská nemocnice Čáslav ¹; SEKK Pardubice ²
Published in the journal: Klin. Biochem. Metab., 23 (44), 2015, No. 1, p. 21-26

Summary

Results obtained in external quality assessment programs show low level of harmonization and comparability in ALP measurement. Dependency of results on the used method/reagent kits are enormous in cases of all types matrices of control samples (individual donor samples, native pool sera, lyophilised sera). Reason of this situation is usual - small number of methods with traceability to IFCC reference method 2011 [3]. Documentation of many methods from many manufacturers systematically confuses real and approved IFCC method 2011 with so called and not valid “reference“ method from 1983, developed originally for incubation temperature 30ºC [1]. Problems with the lack of harmonization are very strongly deteriorated by use of non-standardized and fully obsolete methods with DEA buffer. These methods give very different results from methods with AMP buffer and are still on the marketplace. Mentioned problems lead us to interim interruption of certificate process in external quality assessment program SEKK for ALP. Nevertheless standardization process for ALP slowly continues and our communication comments and documents this process. We dealed with calibration problems of routine methods for ALP based on the reference method 2011 [1]. We propose some tools for achievement of necessary level oh harmonization of ALP measurement results.

Keywords:
Alkaline phosphatase, standardization, reference method, routine measurement, harmonization.

Zdroje

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