Clinical Trial Details
— Status: Completed
Administrative data
NCT number |
NCT04000243 |
Other study ID # |
RAC-M |
Secondary ID |
|
Status |
Completed |
Phase |
|
First received |
|
Last updated |
|
Start date |
July 1, 2019 |
Est. completion date |
December 31, 2020 |
Study information
Verified date |
February 2023 |
Source |
Hospital Clinic of Barcelona |
Contact |
n/a |
Is FDA regulated |
No |
Health authority |
|
Study type |
Observational
|
Clinical Trial Summary
Helicobacter pylori (Hp) is the major cause of gastritis and gastritis-associated diseases.
Detection of a regular arrangement of collecting venules (RAC) pattern in the lesser gastric
curvature correlates with negative Hp status with a sensitivity and negative predictive value
(NPV) higher than 90% in Asian countries.
In a recent study carried out in our hospital, it has been shown that the presence of RAC
pattern in the lesser gastric curvature, evaluated with high definition endoscopy, can
accurately identify patients without Hp.
The aim of this study is to confirm the validity of the endoscopic diagnosis of Hp infection
in the West by means of the RAC pattern in a multicenter prospective study and to evaluate
interobserver variability before establishing its applicability in clinical practice.
Description:
We designed a prospective study including patients who will undergo upper gastrointestinal
endoscopy from July 2019 to June 2020 at the Endoscopy Unit of Hospital Clinic of Barcelona.
The Ethics Committee of Hospital Clinic of Barcelona approved the study.
Upper gastrointestinal endoscopies will be performed with high definition endoscopes
(Olympus, Germany) without magnification by three endoscopists. One of the endoscopists is
considered as an expert with more than 20 years of experience and prior training in Japanese
centers. All the examinations will be performed with sedation controlled by an
anesthesiologist. After the routine examination of the esophagus, stomach, and duodenum,
close observation will be carried out at the distal part of the lesser curvature and pictures
will be taken. The Olympus system will be used for image storing and text reporting.
The presence of a regular or irregular arrangement of collecting venules will be evaluated in
real time during gastric exploration in the lower part of the lesser curvature of the gastric
body with good insufflation, close to the incisura angularis. If minute red points were
visible regularly and homogenously, the finding will be scored as RAC positive (RAC+). If
this finding was absent or there was a patchy distribution at the site of close observation,
it will be defined as RAC negative (RAC-).
The following baseline characteristics will be collected: age, sex, antibiotics, proton-pump
inhibitors, non-steroidal anti-inflammatory drugs (NSAIDs), antithrombotic or anticoagulant
use in the last two weeks, history of Hp eradication and detection of significant endoscopic
findings (erosive duodenitis, non-erosive duodenitis, duodenal ulcer, erosive gastritis,
gastric ulcer and signs of atrophic gastritis or intestinal metaplasia).
Hp infection status will be determined by mucosal biopsies. We will perform 5 samples for
histological study according to Sydney criteria (2 in antrum, 1 in incisura angularis and 2
in gastric body); or 2 biopsies (1 in antrum and 1 in gastric body) for histology and
immunohistochemical study for Hp. Patients were classified as Hp positive if one of these two
tests are positive.
For the histological study, samples will be fixed in formalin and stained with hematoxylin
and eosin for the evaluation of gastritis and with Giemsa for Hp status. The
immunohistochemical study will be carried out systematically in the case of a negative
histological study for Hp. The pathologist has access to the endoscopic diagnosis but not to
RAC status.
Statistical analysis
The quantitative variables will be described by the mean and the standard deviation, while
the qualitative variables by proportion. The sensitivity, specificity, positive predictive
value (PPV), NPV and accuracy of RAC for the diagnosis of uninfected Hp patients will be
calculated. 95% confidence interval will be calculated by using standard formula. Comparisons
will be done using Chi-square test for categorical variables and t test for continuous
variables. In addition, a multivariate logistic regression analysis will be carried out to
assess the existence of predictive factors of RAC and the odds ratio (OR) was calculated to
indicate the associated risk. P <0 .05 will be considered statistically significant. All
statistical analyses will be performed using the SPSS, version 23 (SPSS Inc., Chicago, USA).