Endoscopic features of lymphoid follicles using Blue Laser Imaging (BLI) endoscopy in the colorectum and its association with chronic bowel symptoms in healthy subjects

Tahara T, Okubo M, et al

Gastrointestinal Endoscopy volume 83, 2016

Background/Aim: In the colorectum, lymphoid follicles hyperplasia (LH) are sometimes observed as small, round, yellowish-white nodules. The novel imageenhanced endoscopy system named blue laser imaging (BLI) provides enhanced the contrast of surface vessels using lasers for light illumination. The aim of the present study was to investigate endoscopic features of LH observed by BLI endoscopy and its association with chronic bowel symptoms in
healthy subjects.

Patients/ Methods: 300 healthy participants (median age: 60 years, male/ female: 180/120) undergoing screening colonoscopy were enrolled. After inserting colonoscope in to the cecum, entire colorectum was observed by using BLI-bright mode with non-magnification view. LH was defined as well demarcated white nodules. In particular, elevated LH with erythema was distinguished as LH high.

Results: LHs are observed more clearly by using BLI-bright mode than white light. LHs were histologically confirmed as intense infiltration of lymphocytes or plasmacytes. LH was observed in 134 subjects (44.6%). Among them, 67 (22.3%) was LH high. LH was associated younger age (Odds ratio (OR) = 1.05, 95%Confidence Interval (95%CI) = 1.03-1.07, P<0.0001). The location of LH was 25.3%, 37.7%, 15.3%, 14% 16.7%, and 15.7% in the cecum, ascending colon transverse colon, descending colon, sigmoid colon and rectum, respectively. The presence of LH was significantly associated with chronic bowel symptoms including constipation, hard stools, diarrhea and loose stools (all LH: OR=4.03, 95%CI=2.36-6.89, P<0.0001, LH high: OR=5.31, 95%CI=2.64-10.71, P<0.0001). LH high was closely associated with both constipation associated symptoms (OR=3.94, 95%CI=1.79-8.66, P=0.0007) and diarrhea associated symptoms (OR=5.22, 95%CI=2.09-13.05, P=0.0004) . In particular, LH high in the ascending colon was strongly associated with bowel symptoms (P<0.0001).

Conclusion: LH, visualized by using BLI endoscopy was associated with bowel symptom, raising the possibility of pathogenic role of this endoscopic finding in the functional lower gastrointestinal disorders.