Application Of The Serological Test For Detection Of Current Helicobacter Pylori Infection In Clinic

Background & Aims:Development of an accurate and noninvasive method to detect current Helicobacter pylori infection is essential in clinic.The aim was to evaluate the performance of the CIM test for current H.pylori infection before and after eradication therapy in Chinese.Methods:452 eligible people were recruited.Each individual underwent a ¹³C-UBT.115 H.pylori-positive outpatients were treated with one-week triple therapy for the evaluation of CIM test performed 1, 3 and 6 months after eradication.Its performance(sensitivity, specificity,etc.)was determined using the ¹³C-UBT as a gold standard.Results:H.pylori was detected in 221(65.6%)of the 337 people by ¹³C-UBT.The sensitivity,specificity,positive and negative predictive values and accuracy of the CIM test were 93.2%,90.5%, 94.9%,87.5%,and 92.3%,respectively.The sensitivity and specificity of CIM test were 50.0%and 66.7%one month after eradication therapy,and they increased to 85.7%and 96.9%six months after the therapy.Conclusions:The CIM test is a simple,rapid,accurate,cheap and near-people test.It may be satisfactory for detecting H.pylori infection in cases without eradication therapy,but it could not differentiate the past or current infection within 6 months after anti-H,pylori therapy. Background & Aims:Gastric cancer is the common cancer in the world and particularly prevalent in certain countries including China.H pylori is a definite careinogen for gastric adenocarcinoma.However,the underlying pathogenic mechanisms have not been fully understood,although the interactions between environmental,bacterial and multiple genetic components are likely to be involved.MDM2(mouse double minute)is an oncogene,and can inhibit p53 passway.We hypothesized that genetic variations of MDM2(SNP309)was associated with gastric cancer susceptibility.To test this hypothesis, we performed genotyping analysis for MDM2 309T＞G in a casecontrol study of 260 gastric cancer cases and 260 age and sex frequency-matched healthy controls from Han population of Jiangsu province.Methods:This study consisted of 260 patients with gastric cancer and 260 healthy controls.All subjects were unrelated ethnic Han Chinese and residents in Jiangsu Province.All cases were pathologically diagnosed as gastric carcinoma.The population controls were selected from cancer-free individuals living in Jiangsu Province,and were frequency matched to the cases on age(±5 years)and sex.Trained interviewers used a pre-tested questionnaire to determine demographic and lifestyle characteristics,such as sex,age,and related risk factors,including tobacco smoking,alcohol drinking,etc. SNP309 was genotyped by polymerase chain reaction restriction fragment length polymorphism(PCR-RFLP).The indirect solid phase immunochromatographic assay was used to investigate the presence of IgG antibodies to H.pylori(Genelabs Diagnostics Pty Ltd, Singapore).Results:The cancer cases and controls seemed to be adequately matched in terms of sex and age.There was no difference between patients and controls in Hp seropositivity.The observed genotype frequencies of MDM2 polymorphism was in Hardy-Weinberg equilibrium in the controls(P=0.06).Distributions of MDM2 genotypes were then compared among patients and controls.The frequencies of MDM2 TT, TG,and GG genotypes among patients were significantly different from those among controls(P=0.006),with the GG homozygotes being overrepresented among patients compared with controls(25.4% versus 14.2%;P=0.009).The MDM2 GG genotype was associated with an increased risk of developing GC(OR,1.98;95%CI, 1.186-3.307;P=0.009),compared with TT genotype.However,the heterozygous genotypes MDM2 TG was not associated with the risk. Significant interactions were observed between polymorphisms and Hp,with risk being the highest(OR,2.947;95%CI,1.592-5.457)in Hp seropositivity having MDM2 GG genotypes.Conclusions:In conclusion,our study shows a significant association between functional polymorphisms in MDM2 and increased risk of gastric cancer...