Improved diagnostic accuracy of a modified oral pancreatic function test

Area of Science:

• Gastroenterology
• Diagnostic Medicine
• Biochemistry

Background:

• The standard oral pancreatic function test (PFT) relies on urinary recovery of p-aminobenzoic acid (PABA).
• Its diagnostic accuracy is limited by false positives in patients with impaired PABA absorption or conjugation due to liver or bowel disease.
• Normal pancreatic function can be misdiagnosed in these cases.

Purpose of the Study:

• To modify the oral PFT to account for impaired PABA absorption and conjugation.
• To develop a PABA excretion index (PEI) for improved diagnostic specificity.
• To differentiate pancreatic disease from liver and small-bowel conditions.

Main Methods:

• Oral administration of N-benzoyl-L-tyrosyl-p-aminobenzoid acid for the PFT.
• Comparison of PFT results with urinary recovery of free PABA.
• Calculation of the PABA excretion index (PEI) to correct for absorption and conjugation variations.

Main Results:

• The PEI successfully distinguished patients with pancreatic disease from healthy individuals.
• In patients with liver or small-bowel disease, the PEI yielded results similar to normal subjects, unlike the standard PFT.
• The modified test accurately identified pancreatic disease while excluding falsely abnormal results from other conditions.

Conclusions:

• The modified oral PFT, utilizing the PEI, offers enhanced diagnostic value for pancreatic exocrine function.
• This approach effectively overcomes the limitations of the standard PFT in patients with gastrointestinal or hepatic disorders.
• The PEI provides a more reliable method for diagnosing pancreatic insufficiency.