GI Endoscopy · 1 min read

The Lewis Score for Inflammatory Enteropathy Assessment

Discover expert capsule endoscopy interpretation guidelines for small bowel bleeding. Learn how to accurately diagnose and manage gastrointestinal disorders with our comprehensive guide.

Clinical Bottom Line

Lewis Score (LS) ThresholdEndoscopic InterpretationClinical Action
LS < 135Normal, healthy small intestine.Strongly supports ending active surveillance for Crohn's in the small bowel.
LS > 790Severe, destructive inflammation and massive ulceration.Mandates an immediate, aggressive escalation of advanced biologic therapies.

Standardizing the Pill Camera

Video Capsule Endoscopy (VCE) generates a staggering 50,000 images during its 8-hour transit through the highly coiled, dark 6 meters of the small intestine. Historically, physicians read these massive studies and dictated highly subjective reports ("Saw some red spots in the middle third..."). This lack of structured grading made tracking the efficacy of biologic therapies entirely impossible.

The Quantitative Metric

The Lewis Score eradicated this subjectivity. It is a highly rigidly validated mathematical index specifically designed for capsule endoscopy. The scoring algorithm physically breaks the small intestine into three distinct "tertiles" (based on transit time). It violently grades the severity and distribution of villous edema, ulcer length, and luminal stricturing. By assigning rigid mathematical weights to these visual findings, the capsule software outputs a hard numerical score. When a physician prescribes a new biologic for severe Crohn's, a baseline Lewis Score of 900 acts as the definitive benchmark. A repeat capsule 6 months later mathematically proves healing if the score drops below 135.


Clinical guidelines summarized by the Gastroscholar Research Team. Last updated: 2026. This article is intended for physicians.

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