La eficacia de la imagen de banda estrecha para la detección de metaplasia intestinal en pacientes adultos con síntomas de dispepsia

Usefulness of optical enhancement endoscopy combined with magnification to improve detection of intestinal metaplasia in the stomach

Background and study aims  The light blue crest observed in narrow band imaging endoscopy has high diagnostic accuracy for diagnosis of gastric intestinal metaplasia (GIM). The objective of this prospective study was to evaluate the diagnostic accuracy of magnifying i-scan optical enhancement (OE) imaging for diagnosing the LBC sign in patients with different levels of risk for gastric cancer in a Mexican clinical practice. Patients and methods  Patients with a history of peptic ulcer and symptoms of dyspepsia or gastroesophageal reflux disease were enrolled. Diagnosis of GIM was made at the predetermined anatomical location and white light endoscopy and i-scan OE Mode 1 were captured at the two predetermined biopsy sites (antrum and pyloric regions). Results  A total of 328 patients were enrolled in this study. Overall GIM prevalence was 33.8 %. The GIM distribution was 95.4 % in the antrum and 40.5 % in the corpus. According to the Operative Link on Gastritis/Intestinal-Metaplasia Assessment staging system, only two patients (1.9 %) were classified with high-risk stage disease. Sensitivity, specificity, positive​ and negative predictive values, positive and negative likelihood ratios, and accuracy of both methods (95 % C. I.) were 0.50 (0.41-0.60), 0.55 (0.48-0.62), 0.36 (0.31-0.42), 0.68 (0.63-0.73), 1.12 (0.9-1.4), 0.9 (0.7-1.1), and 0.53 (0.43-0.60) for WLE, and 0.96 (0.90-0.99), 0.91 (0.86-0.94), 0.84 (0.78-0.89), 0.98 (0.94-0.99), 10.4 (6.8-16), 0.05 (0.02-0.12), and 0.93 (0.89-0.95), respectively. The kappa concordance was 0.67 and the reliability coefficient was 0.7407 for interobserver variability. Conclusions  Our study demonstrated the high performance of magnifying i-scan OE imaging for endoscopic diagnosis of GIM in Mexican patients.

Narrow band imaging for detection of gastric intestinal metaplasia and dysplasia: A systematic review and meta-analysis

BACKGROUND AND AIMS

Gastric intestinal metaplasia (GIM), a precursor of gastric adenocarcinoma, is challenging to diagnose with white light endoscopy (WLE) and can be missed by random gastric biopsies. Narrowband imaging (NBI) may potentially improve the detection of GIM. However, pooled estimates from prospective studies are lacking.

METHODS

Electronic databases were searched for studies comparing NBI and WLE alone for detection of GIM and synchronous dysplasia. Primary outcome was pooled detection rate of GIM by NBI compared with WLE in prospective studies. The secondary outcome was concurrent dysplasia detection.

RESULTS

Ten studies were found eligible from 306 articles screened. Eight prospective studies were found eligible for primary endpoint of GIM detection. Two other retrospective studies were included for dysplasia detection. A total of 1366 subjects (694 males, 54.4 ± 5.08 years) underwent upper endoscopy. GIM was detected in 482 (35.3%) subjects. NBI detected GIM in 32% additional subjects (70% vs 38%, RR 1.79; 95% CI 1.34-2.37; P < 0.01). Subgroup analysis revealed newer NBI scopes (GIF260) detected significantly more GIM than WLE (RR 2.47; 95% CI 1.63-3.76; P < 0.01) but not the older (H180) NBI endoscopes (RR 1.33; 95% CI 0.93-1.88; P = 0.11). There was moderate heterogeneity between the studies (I²  = 63%). In five studies (n = 628) that reported dysplasia, there was no significant difference between NBI and WLE in dysplasia detection (RR 1.09; 95% CI 0.81-1.47; P = 0.58).

CONCLUSION

Narrowband imaging can significantly increase the detection of GIM when used in addition to standard white light exam during an upper endoscopy.

Markers of gastric intestinal metaplasia under digital chromoendoscopy: systematic review and meta-analysis

Diagnosis of gastric intestinal metaplasia (GIM) under digital chromoendoscopy presents various markers. The diagnostic yield of each marker has shown variable results. A systematic review and meta-analysis were performed to evaluate the following markers: light blue crest (LBC), marginal turbid band (MTB), groove type (GT), white opaque substance (WOS). Discussion of their joint diagnosis, reliability, assessment of local GIM severity and influencing factors was also provided. PubMed, EMBASE, Cochrane Library and Web of science were searched. The Meta-DiSc and Stata software were used to analyze the data. Fourteen studies were included with a total of 3081 lesions. There were 12 studies for LBC, six for GT, four for MTB and one for WOS, respectively. The pooled results showed that the diagnostic sensitivity and specificity of LBC were 0.79 [95% confidence interval (CI) 0.76-0.81] and 0.95 (95% CI 0.94-0.96). The sensitivity of GT and MTB were 0.49 (95% CI 0.43-0.54) and 0.47 (95% CI 0.40-0.53), and the specificity were 0.92 (95% CI 0.89-0.94) and 0.92 (95% CI 0.89-0.95). The area under the summary receiver operating characteristic curve was 0.9532, 0.7791 and 0.9553 for LBC, GT and MTB, respectively. LBC resulted the most classic marker. Proper combined diagnosis can improve the diagnostic efficiency. Reliability of these markers was acceptable. These markers can help endoscopic to assess the severity of local GIM. Besides intestinal metaplasia, many factors can potentially interfere with the diagnosis.