Study On The Diagnosis Of Helicobacter Pylori And Atrophy Of Gastric Mucosa And Intestinal Metaplasia

1 BackgroundSince helicobacter pylori(HP)was firstly isolated and cultured from human gastric mucosa by Australian scholars Barry Mashall and Rabin Warrenmore than 30 years ago(1983),invasive methods,tissue section staining,rapid urease and PCR-Hp-DNA method,were applied to detect HP infection.While non-invasive diagnostic methods such as,13 C or 14 C urea breath test,blood and saliva Hp specific antibody detection,and fecal HP antigen detection were also used to detect HP infection.A large number of researches have reported that HP infection is closely correlated with the occurrence of diseases such as atrophic gastritis,intestinal metaplasia and gastric cancer.On the other hand,with the development of endoscopy,staining and magnifying endoscopy have become an important method for diagnosis of diseases such as atrophic gastritis,intestinal metaplasia and gastric cancer.However,in clinical practice,the diagnosis of Helicobacter pylori infection,atrophic gastritis and intestinal metaplasia in endoscopy are still difficult to standardize and accurately diagnose.In view of this,our research studies on the following contents:2 Objectives2.1 To compare detection methods of Helicobacter pylori with the clinical diagnostic value and influencing factors of the methods.2.2 To analyze the value of application white light endoscopy and narrow-band imaging magnifying endoscopy(NBI-ME)in the diagnosis of gastric mucosal atrophy and intestinal metaplasia,then to explore the relationship between the gastric mucosal atrophy togethet with intestinal metaplasia and morphological changes in the stomach under narrow-band imaging magnifying endoscopy(NBI-ME).3 Methods3.1 192 patients were detected by polymerase chain reaction(PCR),rapid urease test (RUT),14 C urea breath test(14C-UBT),blood HP antibody test(HP-Ig G)and histopathological examination respectively.With histopathological examination were performed as the "gold standard",the sensitivity and specificity of other methods were compared.3.2 384 patients underwent endoscopy were randomly divided into teo groups,white light group and NBI-ME group.The conformity in diagnosis of the results between histology and endoscopy examination of patients,from the two groups,were compared.While applied with Sakaki classification standard,the relationship between atrophy,intestinal metaplasia and mucosal microstructure were also analyzed.4 Results4.1 When applied histopathological examination as the "gold standard" for diagnosis of HP infection,the sensitivity of 14 C urea breath test(14C-UBT)was lower than that of PCR while the specificity,accuracy,PPV and NPV were better than other methods.Besides,the consistency with the "gold standard" is higher(Kappa value = 0.62).When the UBT method was performed with a DMP value of ?100,the area under the ROC curve was 0.811,and the sensitivity,specificity,and accuracy were 83.7%,78.5%,and 81.3%,respectively.When the DMP value was increased to?209,the area under the ROC curve was 0.848,and the sensitivity,specificity,while accuracy were76.3%,93.4%,and 84.4%,respectively.4.2 When applied histopathological examination as the "gold standard" for diagnosis of gastric mucosal atrophy and intestinal metaplasia.For diagnosis of atrophy,the consistency of NBI-ME was significantly higher than that of white light endoscopy(Kappa value 87.16% vs 50.49%).While for diagnosis of intestinal metaplasia,the consistency of NBI-ME was also significantly higher than white endoscopy(Kappa value 91.88% vs 59.04%)).When applied Sakaki classification in images of NBI-ME endoscopy,type II and type III can be used for the diagnosis of atrophy while type IV and type V can be used for the diagnosis of intestinal metaplasia.5 Conclusion5.1 When applied histopathological examination as the "gold standard" for diagnosis of HP infection,14 C urea breath test(14C-UBT)were compared with other methods such as rapid urease test(RUT),polymerase chain reaction(PCR)and blood HP antibody detection(HP-Ig G),which has the best ability to detect HP infection with a threshold of 209 DPM for optimal diagnosis.5.2 Magnifying endoscopy(ME)and narrow band imaging(NBI),as the new techniques for digestive endoscopy examination,which improve the efficacy in diagnosis of lesions.Under NBI-ME endoscopy,we can determine the nature of gastric mucosal lesions based on morphological changes in gastric mucosa.Compared with white endoscopy,NBI-ME combined with Sakaki classification can effectively improve rate of detection endoscopic gastric mucosal atrophy and intestinal metaplasia.And which also provide an important method for screening gastric mucosal lesions.