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 verze

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

1. Tietz, N. W., Rinker, A. D., Shaw, L. M. IFCC me-thods for the measurement of catalytic concentration of enzymes: Part 5. IFCC method for alkaline phosphatase (orthophosphoric-monoester phosphohydrolase, alkaline optimum, EC 3.1.3.1). Clin. Chim. Acta, 1983,135/3: p. 339 - 349.

2. Tietz, N. W., Burtis, C. A., Duncan, P., Ervin, K., Petitclerc, C. J., Rinker, A. D. et al. A reference method for measurement of alkaline phosphatase aktivity in human serum. Clin. Chem. 1983, 29/5: p. 751 – 761.

3. Schumann, G., Klauke, R., Canalias, F., Bossert-Reuter, S., Franck, P. F. H., Gella, F. J. et al. IFCC primary reference procedures for the measurement of catalytic activity concentrations of enzymes at 37º C. Part 9: Reference procedure for the measurement of catalytic concentration of alkaline phosphatase. Clin. Chem. Lab. Med. 2011, 49/9: p. 1439 - 1446.

4. Dostupné na webové adrese: http://www.sekk.cz/ ke dni 23. 1. 2015.

5. Dostupné na webové adrese: http://www.dgkl-rfb.de/ ke dni 23. 1. 2015.

6. Thienpont, L., Stöckl, D. Master Comparison 2014. Preliminary Report Assay Performance. STT Consulting /University Gent Belgium, 25. 7. 2014. Dostupné na: http://www.stt-consulting.com/news.php?rubriek=8.

7. Weykamp, C., Franck, P., Gunnewiek, J. K., de Jonge, R., Kuypers, A., van Loon, D. et al. Harmonisation of seven common enzyme results througth EQA. Clin. Chem. Lab. Med. 2014, 52: p. 1549 – 1555.

8. CLSI EP30-A. Characterization and qualification of commutable reference materials for laboratory medicine; approved guideline. Wayne PA, CLSI 2010.

9. Dostupné na webové adrese: http://www.dgkl-rfb.de:81/index.shtlm ke dni 23. 1. 2015.

10. Firemní dokumentace Roche. ALP podle IFCC Gen 2. Nová referenční standardizace, reasignace cílových hodnot. Srpen 2014. Roche Diagnostics CZ.

11. Rosler, D., Yahalom, J., Lennartz, L., Armbruster, D., Gao, S., Orth, M. Traceability of Abbott enzyme assays to IFCC reference method – International study. Annual meeting AACC. Los Angeles, July 15 – 19. 7. 2012.

12. Christoph, J. Änderung der pädiatrischen Referenzwerte der Alkalischen Phosphatase bei Messung gemäss IFCC 2011. Deutsche Kongress für Laboratoriumsmedizin DGKL, Mannheim 24 – 27. 9. 2014.