[The limits of the reference range of serum enzymes]

The reference ranges of some of the most frequently used in the clinical laboratory practice serum enzymes and isoenzymes are determined: aspartate aminotransferase (ASAT), alanine aminotransferase (ALAT), creatine kinase (CK) and its isoenzyme (CK-MB), lactate dehydrogenase (LDH) and its isoenzyme--HBDH, and alkaline phosphatase (APh). The reference ranges of the enzymes and isoenzymes studied are calculated from the results obtained in 182 clinically healthy persons, 20-50 years of age, by the "single test" method. All analyses are made with the flexible discrete analyzer "Technicon PA 1000". The influence of several factors is studied. The age of the patients does not exert any influence on the enzymes and isoenzymes studied. Statistically significant sex dependent differences are established for CK, ASAT, ALAT and APh. The statistical processing of the results for the determination of the reference ranges of the enzymes and isoenzymes studied is accomplished with a computer "Hewlett Packard 85".