Published online Feb 16, 2019. doi: 10.4253/wjge.v11.i2.145
Peer-review started: November 5, 2018
First decision: November 28, 2018
Revised: January 9, 2019
Accepted: January 26, 2019
Article in press: January 26, 2019
Published online: February 16, 2019
Duodenal mucosal biopsies are routinely obtained during upper endoscopy (EGD) but very often are histopathologically normal.
To decrease unnecessary biopsies, a more strategic method for examining the duodenal mucosa is needed.
The primary aim of this study was to examine the clinical utility of narrow band imaging (NBI) for evaluating the morphology.
We performed a prospective cohort study of patients at Mayo Clinic Rochester who were referred for EGD with a request for duodenal biopsies. The performing staff endoscopist scored, in real-time during EGD, the NBI-based appearance of duodenal villi into one of three categories (normal, partial villous atrophy, or complete villous atrophy), captured ≥ 2 representative duodenal NBI images, and obtained duodenal mucosal biopsies. NBI images were then scored by an advanced endoscopist and fellow, and biopsies (gold standard) by a pathologist, in a masked fashion using the same three-category classification. Performing endoscopist, advanced endoscopist, and fellow NBI scores were compared to histopathology scores to calculate performance characteristics [sensitivity, specificity, positive and negative (NPV) predictive values, and accuracy]. Inter-rater agreement was assessed with Cohen’s kappa.
A total of 112 patients were included in the study. The most common referring indications for EGD with duodenal biopsies were dyspepsia (47%), nausea (23%), and suspected celiac disease (14%). Histopathology scores of duodenal biopsies were: 84% normal, 11% partial atrophy, and 5% complete atrophy. Performing endoscopist duodenal NBI scores were 79% normal, 14% partial atrophy, and 6% complete atrophy compared to 91%, 5%, and 4% and 70%, 24%, and 6% for advanced endoscopist and GI fellow, respectively. Diagnostic performance was favorable for all three raters compared to histopathology, and NPV was particularly high (92-100%). NBI score agreement was best between performing endoscopist and fellow (κ = 0.65).
NBI inspection during EGD facilitates accurate, non-invasive evaluation of duodenal villi. It’s particularly high NPV may render it most useful for foregoing biopsies of duodenal mucosa likely to be histopathologically normal.
We believe NBI should routinely be applied to the duodenum during EGD prior to obtaining duodenal biopsies in order to help determine their likely histopathological yield and better target (rather than randomly approach) their acquisition.