Investigation on Causes of False-negative 14 C-Urea Breath Test / 胃肠病学

ABSTRACT

Background:14 C-urea breath test(14 C-UBT)is widely used for diagnosis of Helicobacter pylori(Hp)infection owing to its noninvasiveness and high sensitivity and specificity. Nevertheless,the presence of false-negative result can influence the diagnostic accuracy. Aims:To investigate the possible causes of false-negative 14 C-UBT for improving the accuracy of diagnosis. Methods:Eight-two cases with confirmed false-negative 14 C-UBT and 813 controls with true-positive 14 C-UBT at the People’s Hospital of Xinjiang Uygur Autonomous Region from Jan. 2014 to Aug. 2014 were enrolled. Patients in both groups were diagnosed as positive for Hp infection by Warthin-Starry silver staining combined with Hp stool antigen test. Univariate and multivariate analysis were performed to screen the factors related with false-negative 14 C-UBT. Results:In univariate analysis,5 variables were significantly different between case group and control group(P ﹤ 0. 05),and were taken into the multivariate analysis. Logistic stepwise regression analysis revealed that bile reflux( OR = 3. 961,P ﹤0. 001),post subtotal gastrectomy(OR = 9. 734,P ﹤ 0. 001),type Ⅱ Hp infection(OR = 1. 892,P = 0. 012)and upper gastrointestinal bleeding( OR = 4. 979,P ﹤ 0. 001 ) were the independent risk factors for false-negative 14 C-UBT. Conclusions:Bile reflux,upper gastrointestinal bleeding,post subtotal gastrectomy and type Ⅱ Hp infection might be the influential factors for false-negative 14 C-UBT. Combined tests for Hp infection should be suggested in patients with negative 14 C-UBT who had undergone subtotal gastrectomy or complicated with bile reflux or upper gastrointestinal bleeding.