Comparative determinations of aminotransferase activities in serum with so-called "optimised" methods

Area of Science:

• Clinical enzymology
• Biochemical analysis
• Diagnostic assay development

Background:

• Standardized methods for measuring enzyme activities are crucial for accurate clinical diagnostics.
• Optimized assay methods for aspartate aminotransferase (AST) and alanine aminotransferase (ALT) have been introduced in various regions.

Purpose of the Study:

• To compare the results obtained from different optimized methods for AST and ALT activity determination.
• To assess the clinical significance of observed differences between these assay methods.

Main Methods:

• Comparative analysis of AST and ALT activities using optimized methods from G.D.R., G.F.R., and Scandinavia.
• Statistical evaluation using the paired t-test to identify significant differences.
• Comparison with the IFCC reference method at 37°C.

Main Results:

• Significant differences in AST and ALT activities were detected between the compared optimized methods.
• Observed variations are partly attributed to differing reaction conditions.
• AST activities measured by the IFCC reference method were approximately 30% lower than those determined by other methods at 37°C.

Conclusions:

• While statistically significant differences exist between optimized AST and ALT assay methods, they are unlikely to impact clinical interpretations.
• Assay conditions significantly influence enzyme activity measurements, highlighting the importance of method standardization.
• The IFCC reference method provides a lower baseline for AST activity compared to commonly used optimized methods.