The poor man's isoamylase analysis (wheat inhibitor). Does it work?

Area of Science:

• Clinical Chemistry
• Biochemical Diagnostics

Background:

• Serum amylase is a key diagnostic marker.
• Distinguishing isoamylase fractions is crucial for accurate diagnosis.
• Existing methods for isoamylase analysis can be complex.

Purpose of the Study:

• To evaluate the clinical utility of the wheat inhibitor assay for measuring serum pancreatic isoamylase.
• To compare the wheat inhibitor assay with cellulose acetate membrane electrophoresis for isoamylase analysis.

Main Methods:

• A clinical trial involving 54 patients with diverse disorders.
• Comparison of serum pancreatic isoamylase levels determined by wheat inhibitor assay and cellulose acetate membrane electrophoresis.
• Analysis of correlation, specificity, and sensitivity.

Main Results:

• Excellent overall correlation (r = 0.96) between the two methods.
• The correlation was strongest at high total serum amylase levels.
• Correct prediction of the predominant serum isoamylase in 83% of patients (specificity 73%, sensitivity 96%).

Conclusions:

• The wheat inhibitor assay is a valuable and reliable method for assessing serum pancreatic isoamylase.
• Its ease of performance makes it suitable for routine clinical settings, particularly where advanced analysis is unavailable.
• The assay demonstrates high sensitivity and good specificity for pancreatic isoamylase measurement.