EPI Testing Strategies: What to Order and When

This episode offers a practical, clinically grounded review of the diagnostic tools used to confirm EPI. Sarah Enslin describes her two-track approach: in patients with imaging findings consistent with chronic pancreatitis and high clinical suspicion, she empirically initiates treatment—this is a high-yield, low-risk approach that benefits the already-suffering patient. For patients where the diagnosis is less certain, pancreatic fecal elastase is the preferred test, with the critical caveat that it must be collected on a semi-solid or solid stool. For patients with significant diarrhea, she recommends first working to bulk the stool before collecting the sample to improve accuracy.

Jennifer Geremia builds on this with imaging guidance: CT and MRI findings consistent with chronic pancreatitis or necrotizing pancreatitis strongly support empirical treatment. He issues an important clinical reminder—when pancreatic calcifications are visible on x-ray or CT in the right clinical context, a comprehensive workup is not necessary. Fecal elastase is the current clinical standard and does not vary significantly between labs.

The panel addresses common testing pitfalls. Fecal fat collection, while the historical gold standard, is rarely feasible in modern practice—requiring controlled dietary fat intake over several days before collection. The panelists candidly note that in nearly two decades of practice each, they have rarely seen it performed correctly. Repeat fecal elastase testing to monitor treatment response is also discouraged, as exogenous PERT does not affect the test result. Re-testing after an initial event to monitor for new EPI development remains appropriate.

Endoscopic ultrasound (EUS) is highlighted as a useful adjunct, particularly for suspected small duct or minimal change disease. As many patients with EPI already undergo upper endoscopy, EUS can be added with relatively low procedural risk using established Rosemont criteria. Blood-based testing and the triglyceride breath test are discussed as emerging modalities that remain largely investigational or commercially unavailable in most settings.

In the next episode, "Navigating the Differential: When EPI Looks Like Something Else," the discussion turns to the conditions most likely to be confused with EPI and how to build a rational, stepwise screening strategy.