Crohn's Lewis Score and CECDAI: Capsule Results Explained

Capsule endoscopy can inspect small-bowel lining that conventional upper endoscopy and colonoscopy may not reach. The Lewis score and Capsule Endoscopy Crohn’s Disease Activity Index, or CECDAI, convert those images into measures of mucosal inflammation. CECDAI is also called the Niv score. Neither score diagnoses Crohn’s disease by itself, and neither includes CRP, fecal calprotectin, hemoglobin, or iron studies. They describe what the capsule camera recorded, while the diagnosis still depends on the whole clinical picture and exclusion of other causes of small-bowel injury (capsule-score systematic review; capsule endoscopy review).

How the Lewis score works

The Lewis score grades edema, ulceration, and stenosis. Capsule transit through the small bowel is divided into three time-based tertiles. Inflammation is assessed within those portions, and the calculation emphasizes the tertile with the greatest inflammatory burden while incorporating stenosis findings. Published interpretation commonly describes a score below 135 as normal or clinically insignificant, 135 to 790 as mild, and 790 or more as moderate-to-severe inflammation. Those bands quantify capsule findings; they do not identify the cause (capsule-score systematic review).

Nonsteroidal anti-inflammatory drugs, infection, celiac disease, ischemia, and other conditions can produce small-bowel lesions. Preparation quality and rapid or incomplete transit can also affect what is seen. A useful report therefore includes lesion location, ulcer size and number, edema, narrowing, whether the capsule reached the colon, and relevant medication exposure, not only a total.

How CECDAI differs

CECDAI scores inflammation severity, extent, and strictures in proximal and distal small-bowel segments. Segmental values are combined into a total. Unlike the Lewis approach, it does not use three transit tertiles in the same way. Because the systems divide and weight findings differently, a Lewis score cannot be converted reliably into a CECDAI value. Serial comparisons are clearest when the same index and reporting method are used (capsule endoscopy review).

Capsule endoscopy views mucosa but does not biopsy it. It also cannot fully characterize disease outside the bowel lumen. MRE or CT enterography may be needed when the question involves transmural inflammation, fistula, abscess, or the nature of a stricture (cross-sectional imaging review).

Why labs matter before and after capsule testing

Calprotectin, CRP, anemia, or iron deficiency may help create the reason for investigating the small bowel, yet those results are not plugged into either capsule formula. Biomarkers can disagree with a capsule score because they measure different biological signals and have different limitations. Treat-to-target guidance uses symptoms, biomarkers, and endoscopic healing as separate, complementary targets (STRIDE-II).

The possibility of capsule retention deserves special attention when Crohn’s has caused suspected narrowing. Clinicians may use cross-sectional imaging or a dissolvable patency capsule before the diagnostic capsule in higher-risk situations (capsule endoscopy review). Contact the ordering team urgently for severe persistent pain, vomiting, swelling, or inability to pass stool after a capsule study.

Save the exact score name, total, segment findings, completion status, and preparation quality. Add NSAID exposure, symptoms, calprotectin, CRP, CBC and iron results, and nearby imaging. The score is most useful as a structured description of small-bowel mucosa on one date. It is not a stand-alone diagnosis and should not be used to start, stop, or change treatment without your gastroenterology team.

Questions that make the number more useful

Before comparing this result with an older one, confirm that both records used the same named instrument, version, scoring range, and assessment window. Ask whether the total represents the worst segment, a sum across segments, an average, or a single day. If a clinician or study used a modified version, record exactly what was removed or added. Also check whether treatment, bowel preparation, infection, missed diary entries, or incomplete examination affected the inputs. A small apparent change may reflect measurement conditions rather than a meaningful change in disease.

At a visit, useful questions include: What domain does this score measure? Which component drove the result? What would count as response or remission in this setting? Does the number need confirmation with blood work, stool testing, endoscopy, biopsy, or imaging? Is the goal to follow symptoms, current inflammation, structural damage, treatment response, or quality of life? Asking these questions turns an unfamiliar total into a specific clinical conversation.

For personal tracking, avoid combining unlike scores on one graph. Keep each instrument in its own series and place objective tests on parallel timelines. Save the source report because the component details may matter later. Note both the sample or procedure date and the date you received the result. Trends are easiest to interpret when the method and timing stay consistent. If the number conflicts with how you feel or with another test, bring the disagreement to your care team instead of choosing the result that seems most reassuring. Discordance is often the reason to look more closely.