Gamma-glutamyltransferase and its isoenzymes: progress and problems.

Area of Science:

• Biochemistry
• Clinical diagnostics
• Enzymology

Background:

• Gamma-glutamyltransferase (GGT) is a key diagnostic marker for hepatobiliary disorders due to its sensitivity to excretory liver function.
• GGT exists in various electrophoretically distinct forms across organs like the liver, kidney, pancreas, and intestine, complicating organ-specific diagnosis.
• While GGT isoenzyme activity changes in disease, definitive disease-specific patterns remain controversial.

Purpose of the Study:

• To evaluate the diagnostic utility of gamma-glutamyltransferase (GGT) in differentiating liver diseases.
• To explore the relationship between GGT isoenzyme findings and diseases of the liver, kidney, pancreas, and intestine.
• To identify areas for future research to improve the clinical applicability of GGT isoenzyme analysis.

Main Methods:

• Review of existing literature on GGT biochemistry, structure, and immunochemistry.
• Analysis of studies correlating GGT isoenzyme patterns with various hepatobiliary and related organ diseases.
• Discussion of challenges in GGT assay standardization and terminology.

Main Results:

• GGT assay is highly sensitive to excretory liver function, making it valuable for detecting hepatobiliary dysfunction.
• The diagnostic value of GGT in the differential diagnosis of specific liver diseases is currently limited.
• While GGT isoenzyme activities vary with disease, universally accepted disease-specific patterns are not established.

Conclusions:

• Further research into GGT isoenzyme characterization and standardization is necessary.
• Improved correlation between GGT isoenzyme findings and specific diseases is crucial for enhancing clinical applicability.
• Standardization of methods and terminology will aid in the consistent interpretation of GGT isoenzyme results.