Diagnostic accuracy of CT enterography correlated to histopathology in the diagnosis of small bowel Crohn's disease.

backgroundCrohn's disease (CD) is a chronic inflammatory process affecting the gastrointestinal tract, mainly the terminal ileum of small bowel. Although ileocolonoscopy provides good mucosal visualization, it does not allow evaluation of extraluminal abnormalities. Computed tomographic enterography (CTE) is an emerging imaging modality for assessment of small bowel disorders. The study aimed to explore the diagnostic accuracy of CTE in the diagnosis of patients with CD benchmarked against a histopathological reference.

methodsA cross-sectional study entailed 126 consecutive patients with known or suspected CD who underwent CTE and biopsy by ileocolonoscopy via retrograde terminal ileum intubation. Spearman's rank was used to test the correlation and Kappa coefficient agreement between CTE and histopathology. Area under the curve (AUC) of receiver operating characteristic (ROC) was used to measure CTE diagnostic accuracy.

resultsThe overall sensitivity and specificity of CTE were 93.88% and 85.71%, respectively. The PPV was 95.83%, and the NPV was 80%. The accuracy of CTE indicated an overall probability of correct patient classification of 92.06%. The AUC of the ROC of CTE was 0.898 (P < 0.001). Thus, CTE has a high sensitivity for assessment of small bowel CD. The CTE and histopathological gradings were strongly correlated (Spearman's coefficient = 0.962, P < 0.001). CTE exhibited perfect agreement with histopathology (Kappa coefficient (κ) = 0.847, P < 0.001).

conclusionCTE is a reliable technique that has high diagnostic accuracy in the assessment of CD. Hence, it may be useful for follow up and for preoperative guidance in treatment planning.