***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
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    ***EXAMPLES*** 
    Input: Background / Objectives : Helicobacter pylori infection and iron and vitamin B12 deficiencies are widespread in economically disadvantaged population s. There is emerging evidence that H. pylori infection has a negative effect on the absorption of these micronutrients . The aim of this study was to evaluate the effect of H. pylori infection on the efficacy of micronutrient ( including iron and vitamin B12)-fortified foods supplied for 1 year in marginally nourished children . Subjects/ Methods : In all , 543 Indian children , aged 6–10 years , participated in a double-blind , r and omized controlled intervention trial , receiving foods fortified with either high ( 100 % Recommended Dietary Allowances ( RDA ) ) or low ( 15 % RDA ) amounts of iron , vitamin B12 and other micronutrients . The presence of H. pylori infection was diagnosed by the 13C-labeled urea breath test at 11 months after the start of the intervention . Blood hemoglobin , serum ferritin ( SF ) , total body iron and plasma vitamin B12 were estimated at baseline and 12 months , and differences between these time points were assessed using an independent t-test . Results : Overall , the prevalence of H. pylori infection in this group of children was 79 % . Baseline hemoglobin , SF , body iron and vitamin B12 concentrations were not associated with H. pylori infection . The response to the intervention ( either high or low amounts of iron and vitamin B12 fortification ) in terms of change in iron markers and vitamin B12 status did not differ between children with and without H. pylori infection . Conclusions : This study shows that the presence of H. pylori infection did not affect the efficacy of long-term iron and vitamin B12 fortification in these marginally nourished children Purpose The aim of this study was to assess and compare the efficacies of proton pump inhibitor-based triple therapy and bismuth-based quadruple therapy as first-line treatments for  Helicobacter pylori eradication in Korean children . Methods We retrospectively review ed the data of children who had been diagnosed with H. pylori infection at the Seoul National University Bundang Hospital from March 2004 to August 2012 . The patients were r and omly assigned to receive either triple therapy consisting of omeprazole , amoxicillin , and clarithromycin for 2 weeks ( OAC group ) or quadruple therapy comprising omeprazole , amoxicillin , metronidazole , and bismuth salts for 1 week ( OAMB group ) . The patients were evaluated for eradication of H. pylori infection at 4 weeks after the completion of the treatment . Results Of the 129 children enrolled in this study , 118 ( 91.5 % ) were included in the final analysis . The eradication rates in OAC and OAMB groups were 67.7 % ( 42/62 ) and 83.9 % ( 47/56 ) , respectively , which were significantly different between the 2 treatment groups ( p=0.041 ) . The eradication rates in the OAMB group during the periods 2004 - 2006 , 2007 - 2009 , and 2010 - 2012 were superior to those in the OAC group . Conclusion This study indicated that the 1-week bismuth-based quadruple therapy , compared with the st and ard 2-week triple therapy , was significantly more successful in eradicating H. pylori infection in Korean children AIM To assess whether antibiotic resistance varies between the antrum and corpus of the stomach of patients that are either Helicobacter pylori ( H. pylori ) therapy-naive or pre-treated . METHODS H. pylori strains were isolated from antrum and corpus biopsies from 66 patients that received a diagnostic gastroduodenoscopy for variant clinical indications . Antimicrobial susceptibility to amoxicillin , clarithromycin , tetracycline , metronidazole , levofloxacin and rifabutin was tested with the E-test method on Iso-Sensitest agar with 10 vol% defibrinated horse blood . In patients with a different antibiotic susceptibility pattern between the isolates from the antrum and corpus , DNA fingerprinting via r and om amplified polymorphic DNA analysis was performed to detect differences among DNA patterns of H. pylori isolates . RESULTS Primary , secondary and tertiary resistance to clarithromycin was 6.9 % , 53.8 % and 83.3 % , retrospectively .  Metronidazole and levofloxacin resistance also increased according to the number of previous treatments ( 17.2 % , 69.2 % , 83.3 % ; 13.8 % , 23.1 % , 33.3 % ) . Tertiary resistance to rifabutin was detected in 12.5 % of patients . In none of the 66 patients a resistance against amoxicillin or tetracycline was detectable . Discordant antibiotic susceptibility between antrum and corpus isolates for different antibiotics was seen in 15.2 % ( 10/66 ) of the patients . Two out of those ten patients were naive to any H. pylori antibiotic treatment . The remaining eight patients previously received at least one eradication therapy . DNA fingerprinting analysis revealed no substantial differences among DNA patterns between antrum and corpus isolates in the majority of patients suggesting an infection with a single H. pylori strain . CONCLUSION Different antibiotic susceptibility between antrum and corpus biopsies is a common phenomenon and a possible explanation for treatment failure . Resistant H. pylori strains may be missed if just one biopsy from one anatomic site of the stomach is taken for H. pylori susceptibility testing In the present study , we investigated the prevalence of anaemia and Fe deficiency anaemia ( IDA ) and explored the relationship between Helicobacter pylori infection and IDA in adolescent girls . A total of 1037 adolescent girls from Suihua , China were enrolled .  Hb , serum ferritin ( SF ) , serum transferrin receptor ( sTfR ) and serum IgG antibodies to H. pylori were measured . Participants with IDA and co-existing H. pylori infection ( n 80 ) who had an intake of > 25 mg/d of Fe were assigned r and omly to the intervention and control groups . Patients in the intervention group were administered a 12-week course of oral EDTA-Na-Fe ( 60 mg Fe/dose , three times a week ) and a 2-week course of colloidal bismuth subcitrate , amoxicillin and metronidazole . Subjects in the control group were administered EDTA-Na-Fe alone .  Hb , SF and sTfR were reassessed 3 months after the 12-week regimen ended . Prevalence of anaemia , Fe deficiency ( defined as SF < 12·0 μg/l ) , IDA and H. pylori infection in the population of 1037 was 19.5 , 40.4 , 17.1 and 31.2 % , respectively . The prevalence of H. pylori infection in the IDA group was 46.9 % , while the non-anaemic group had 28.1 % prevalence . A significant increase in Hb and SF and a decrease in sTfR value were found in the intervention group and the H. pylori-negative group . Findings suggest that IDA is still one of the prominent problems in adolescent girls . There is an association between H. pylori infection and IDA . Treatment of H. pylori infection is associated with a more rapid response to oral Fe therapy IMPORTANCE The long-term effectiveness of Helicobacter pylori eradication programs for preventing gastric cancer will depend on recurrence risk and individual and community factors . OBJECTIVE To estimate risk of H. pylori recurrence and assess factors associated with successful eradication 1 year after treatment . DESIGN , SETTING , AND PARTICIPANTS Cohort analysis of 1463 r and omized trial participants aged 21 to 65 years from 7 Latin American communities , who were treated for H. pylori and observed between September 2009 and July 2011 . INTERVENTIONS R and omization to 1 of 3 treatment groups : 14-day lansoprazole , amoxicillin , and clarithromycin ( triple therapy ) ; 5-day lansoprazole and amoxicillin followed by 5-day lansoprazole , clarithromycin , and metronidazole ( sequential ) ; or 5-day lansoprazole , amoxicillin , clarithromycin , and metronidazole ( concomitant ) . Participants with a positive (13)C-urea breath test ( UBT ) 6 to 8 weeks posttreatment were offered voluntary re-treatment with 14-day bismuth-based quadruple therapy . MEASUREMENTS Recurrent infection after a negative posttreatment UBT and factors associated with successful eradication at 1-year follow-up . RESULTS Among participants with UBT-negative results who had a 1-year follow-up UBT ( n=1091 ) , 125 tested UBT positive , a recurrence risk of 11.5 % ( 95 % CI , 9.6%-13.5 % ) . Recurrence was significantly associated with study site ( P = .03 ) , nonadherence to initial therapy ( adjusted odds ratio [ AOR ] , 2.94 ; 95 % CI , 1.31 - 6.13 ; P = .01 ) , and children in the household ( AOR , 1.17 ; 95 % CI , 1.01 - 1.35 per child ; P = .03 ) . Of the 281 with positive posttreatment UBT results , 138 completed re-treatment , of whom 93 tested UBT negative at 1 year . Among the 1340 who had a 1-year UBT , 80.4 % ( 95 % CI , 76.4%-83.9 % ) , 79.8 % ( 95 % CI , 75.8%-83.5 % ) , and 77.8 % ( 95 % CI , 73.6%-81.6 % ) had UBT-negative results in the triple , sequential , and concomitant groups , respectively ( P = .61 ) , with 79.3 % overall effectiveness ( 95 % CI , 77.1%-81.5 % ) . In a single-treatment course analysis that ignored the effects of re-treatment , the percentage of UBT-negative results at 1 year was 72.4 % ( 95 % CI , 69.9%-74.8 % ) and was significantly associated with study site ( P < .001 ) , adherence to initial therapy ( AOR , 0.26 ; 95 % CI , 0.15 - 0.42 ; P < .001 ) , male sex ( AOR , 1.63 ; 95 % CI , 1.25 - 2.13 ; P < .001 ) , and age ( AOR , 1.14 ; 95 % CI , 1.02 - 1.27 per decade ; P = .02 ) . One-year effectiveness among all 1463 enrolled participants , considering all missing UBT results as positive , was 72.7 % ( 95 % CI , 70.3%-74.9 % ) . CONCLUSIONS AND RELEVANCE One year after treatment for H. pylori infection , recurrence occurred in 11.5 % of participants who had negative posttreatment UBT results . Recurrence determinants ( ie , nonadherence and demographics ) may be as important as specific antibiotic regimen in determining the long-term success of H. pylori eradication interventions . Study findings are relevant to the feasibility of programs for the primary prevention of gastric cancer in high-incidence regions of Latin America . TRIAL REGISTRATION clinical trials.gov Identifier : NCT01061437 OBJECTIVES The aim of this study was to prospect ively assess the pattern of evolution of primary resistance to antibiotics in Helicobacter pylori strains isolated from Portuguese children over a 10 year period ( 2000 - 09 ) . METHODS A total of 1115 H. pylori strains were tested for antibiotic susceptibility to clarithromycin , metronidazole , amoxicillin , ciprofloxacin and tetracycline . RESULTS H. pylori strains were isolated from children and adolescents [ ages 4 months-18 years ( mean age 10.17 ± 4.03 years ) ] , comprising 562 ( 50.4 % ) boys and 553 ( 49.6 % ) girls . Overall , the primary resistance rate was 34.7 % to clarithromycin , 13.9 % to metronidazole and 4.6 % to ciprofloxacin , while 6.9 % were resistant to two of these antibiotics simultaneously . Resistance to amoxicillin and to tetracycline  was not detected . In general , the resistance rate was not associated with gender or the children 's age . European ethnicity , when compared with an African background , was associated with clarithromycin resistance [ P = 0.0 
    Output:
    
Conclusions : The primary goal of clinical investigation is to identify the cause of upper gastrointestinal symptoms rather than H pylori infection .