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Updated: Jun 4, 2026
Identification of Novel CK2 Kinase Substrates Using a Versatile Biochemical Approach
Published on: February 21, 2019
Detection of macro-creatine kinase and macroamylase by polyethylene glycol precipitation and ultrafiltration methods
Sara P Wyness1, Joshua J H Hunsaker, Sonia L La'ulu
1ARUP Institute for Clinical and Experimental Pathology, Salt Lake City, UT 84108, USA.
Background:
Macroenzymes may cause elevations in serum enzyme activity. Macroenzymes are not common; however their detection is important because they cause diagnostic confusion and therapeutic errors.
Methods:
We analyzed 2 of the most prevalent macroenzymes in the literature, macro-creatine kinase (macro-CK) and macroamylase, using 2 methods for detection, polyethylene glycol (PEG) precipitation and ultrafiltration (UF). Enzyme measurements were made using a Roche Modular Analytics P analyzer. Imprecision was assessed using quality control material. We evaluated 125 samples from apparently healthy subjects to establish reference intervals. For macro-CK comparison, 94 samples with activities >200 U/l were analyzed with both PEG precipitation and UF and compared to electrophoresis. PEG precipitation and UF were compared for macroamylase detection using 130 samples with amylase activities >110 U/l.
Results:
UF was more precise and demonstrated narrower reference intervals for both analytes. PEG precipitation and UF were able to detect true cases of macro-CK with overall agreement with electrophoresis of 79.8% and 80.9%, respectively. Both methods detected the same number of 'positive' macroamylase samples; however PEG precipitation resulted in a greater number of 'indeterminate' cases.
Conclusion:
This is the first report where UF has been shown useful for the detection of both macro-CK and macroamylase.
