***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 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Objective : Rapid , inexpensive , reliable tests are needed to facilitate the diagnosis of Helicobacter pylori infection . We evaluated the accuracy of the new FlexSure HP whole blood test ( SmithKline Diagnostics , Inc. ) , a rapid , qualitative in-office test for the detection of antibodies to H. pylori utilizing whole blood obtained from a fingerstick . Methods : Five North American sites enrolled patients not previously treated for H. pylori who underwent upper endoscopy . Patients had not received antibiotics , bismuth , or proton pump inhibitors within 4 wk before study enrollment . Bacterial infection was established by the presence of H. pylori in gastric biopsies ( minimum of two ) or positive rapid urease test of antral tissue . The presence of IgG antibodies was determined using FlexSure HP whole blood tests with blood obtained by fingerstick and FlexSure HP serum and ELISA ( HM-CAP ) tests with serum obtained from venipuncture . Results : Three hundred ninety-three patients were enrolled ( 56 % male ; mean age , 46.8 ± 16.0 yr ) .  H. pylori infection was present in 187 ( 48 % ) . Compared with the st and ard of histology and rapid urease test , sensitivity for FlexSure HP whole blood , FlexSure HP serum , and HM-CAP EIA were , respectively , 84 % , 90 % , and 95 % ( p < 0.05 compared with FlexSure HP whole blood ) . There were no statistical differences in specificity or overall accuracy between the three tests . Conclusions : FlexSure HP whole blood demonstrated an accuracy not significantly different from the FlexSure HP serum test but had sensitivity significantly lower than the HM-CAP EIA . FlexSure HP whole blood may be useful for in-office H. pylori diagnosis Abstract Objective : To evaluate the performance of a near patient test for Helicobacter pylori infection in primary care . Design : Validation study performed within a r and omised trial of four management strategies for dyspepsia . Setting : 43 general practice s around Nottingham . Subjects : 394 patients aged 18 - 70 years presenting with recent onset dyspepsia . Main outcome measures : Results of the Flex Sure test compared with an enzyme linked immunosorbent assay ( ELISA ; HM-CAP ) with an identical antigen profile and with results of an earlier validation study in secondary care Diagnostic yield of patients undergoing endoscopy on the basis of their Flex Sure result compared with those of patients referred directly for endoscopy . Results : When used in primary care Flex Sure test had a sensitivity and specificity of 67 % ( 95 % confidence interval 59 % to 75 % ) and 98 % ( 95 % to 99 % ) compared with a sensitivity and specificity of 92 % ( 87 % to 97 % ) and 90 % ( 83 % to 97 % ) when used previously in secondary care . Of the H pylori test and refer group 14 % ( 28/199 ) were found to have conditions for which H pylori eradication was appropriate compared with 23 % ( 39/170 ) of the group referred directly for endoscopy . Conclusions : When used in primary care the sensitivity of the Flex Sure test was significantly poorer than in secondary care About a third of patients who would have benefited from H pylori eradication were not detected . Near patient tests need to be vali date d in primary care before they are incorporated into management policies for dyspepsia . Key messages Near patient tests for H pylori infection have been recommended in the management of dyspepsia in primary care without proper evaluation Such tests should have a high sensitivity to avoid missing treatable illness related to infection The Flex Sure near patient test had a lower sensitivity than previously reported in validation studies performed in secondary care Fewer than expected numbers of patients with H pylori related pathology were identified with the Flex Sure in primary OBJECTIVE : In a recently published multicenter study involving 501 patients undergoing esophagogastroduodenoscopy ( EGD ) throughout Europe , we showed the high accuracy of a recently developed simple test ( HpSA ) to detect Helicobacter pylori ( H. pylori ) antigens in stools of untreated patients . The aim of this study was to assess the diagnostic usefulness of HpSA compared with 13C UBT shortly after H. pylori eradication treatment . METHODS : Of the 501 patients enrolled in the validation study , 279 were found to be H. pylori-positive . These patients were given H. pylori eradicating regimen and asked to return for follow-up EGD with biopsies , 13C UBT and HpSA testing 4 wk after therapy . Follow-up results were available for 235 patients . Of these , 162 consented to all testing and 73 consented only to 13C UBT and HpSA testing . We assessed sensitivity and specificity of both  HpSA  and 13C UBT compared with  biopsy-based methods  in the 162 patients , who accepted follow-up EGD . We also assessed sensitivity and specificity of HpSA  compared with 13C UBT  , arbitrarily chosen as the gold st and ard , in the whole population of 235 patients . RESULTS : Sensitivity and specificity in 162 patients who consented to a second EGD were 93.8 % ( CI : 85.4–100 % ) and 96.9 % ( CI : 93.9–99.9 % ) for HpSA , and 90.6 % ( CI : 80.5–100 % ) and 99.2 % ( CI : 97.7–100 % ) for UBT . Using EGD-based methods as the gold st and ard , 130 of the 162 treated patients ’ H. pylori infection were eradicated ( 125 HpSA-negative , one borderline , and four false-positive ; 129 13C UBT – negative , one false-positive ) , and 32 remained H. pylori-infected ( 30 HpSA-positive , two false-negative , 29 13C UBT – positive , three false negative ) . The overall eradication rate was 80.2 % . The sensitivity and specificity of HpSA relative to UBT as the gold st and ard in the overall population ( n = 235 ) were 95.6 % ( CI : 89.6–100 % ) and 94.7 % ( CI : 91.5–97.9 % ) , respectively . CONCLUSIONS : HpSA has proven to be a useful method in posttreatment eradication testing for H. pylori . Its ease of use , speed , and noninvasive nature make HpSA testing an ideal method for post-treatment monitoring where a second EGD may not be justified Background The diagnosis of Helicobacter pylori is an essential element in the management of many common gastrointestinal pathologies . Previously diagnosis was dependent on the availability of endoscopic biopsy sample s. The advent of non invasive assays such as the C13Urea breath test and Elisa serology have enabled diagnosis , and treatment to be undertaken in the primary care setting . The isolation of Helicobacter pylori antigen from stool has led to the development of a new non-invasive test . Aim A prospect i ve study was design ed to assess and compare the performance of Premier Platinum HpSA with current gold st and ard tests . Methods Consecutive patients undergoing a gastroscopy for investigation of dyspepsia at the Meath and Adelaide hospitals were enrolled . At endoscopy gastric biopsies were taken for histology , microbiology and rapid urease testing . In addition all subjects had C13UBT , serology and stool tests performed . Individuals who were H. pylori positive received st and ard proton pump inhibitor based triple therapy . Following treatment all tests , apart from serology were repeated . Results 54 patients were enrolled , 46 per cent were H. pylori positive . HpSA had a sensitivity and specificity and positive and negative predicted values of 96 per cent , 75 per cent and 80.6 per cent , 75.8 per cent respectively and compared favourably with all other tests . The sensitivity and specificities of the other tests were , histology 79.2 per cent and 100 per cent , culture 68 per cent and 100 per cent , rapid urease test 75 per cent and 100 per cent , serology 75 per cent and 96 per cent and C13 urea breath test 100 per cent and 96.6 per cent . Conclusion The detection of H. pylori antigen in stool by means of a HpSA assay is a new and effective non-invasive means of diagnosis which can be performed in a routine laboratory setting . It is simple to perform and has possible advantages over other non-invasive tests , detecting actual antigen indicating current active infection OBJECTIVE : We prospect ively studied an FDA -approved stool test for the diagnosis of Helicobacter pylori infection based on the detection of antigens shed in stool . METHODS : We studied 108 patients undergoing endoscopy . Stool sample s were collected on the day of the endoscopy and read in a blinded manner by a technician who was unaware of the findings of the endoscopy . The results of stool testing were compared to those of the rapid urease test ( Pyloritek ) . RESULTS : There were 51 patients infected with H. pylori by  rapid urease testing and 57 who were not . The sensitivity of the  stool test  was 86 % ( 95 % confidence interval : 77–96 % ) , the specificity was 91 % ( 81–97 % ) , with a positive predictive value of 89 % ( 77–96 % ) and a negative predictive value of 88 % ( 81–97 % ) . The likelihood ratio for a positive test was 10.18 and the likelihood ratio for a negative test was 0.11 . CONCLUSIONS : The stool test was sensitive and specific for the detection of H. pylori in a U.S. population OBJECTIVES : Published studies have estimated the rate of Helicobacter pylori ( H. pylori ) infection in patients with duodenal ulcer disease to be as high as 95 % ; the majority of remaining duodenal ulcers have been attributed to the use of ulcerogenic drugs such as nonsteroidal antiinflammatory drugs ( NSAIDs ) . We aim ed to assess the H. pylori prevalence rates of U.S. duodenal ulcer patients in large , well-controlled studies . METHODS : More than 2900 patients with endoscopically diagnosed non-NSAID duodenal ulcers were enrolled in a series of six placebo-controlled , double-blind studies conducted in the United States that assessed H. pylori using a combination of tests . Patients were considered infected with H. pylori only if culture growth was observed , or both histological and CLOtest results were positive . Patients were considered uninfected if the results of at least two tests were negative . Patients with missing test results , results of only a single test , or conflicting test results were not evaluable for H. pylori assessment . RESULTS : Of the 2394 endoscopically diagnosed evaluable duodenal ulcer patients , 73 % ( 1737 ) were confirmed infected with H. pylori at study entry . CONCLUSIONS : The results of six carefully design ed and controlled studies suggest that an assumed H. pylori infection rate of approximately 95 % may overestimate the actual rate of H. pylori infection in duodenal ulcer patients in the United States . Although H. pylori infection is an important factor in the etiology of noniatrogenic duodenal ulcer disease , other factors may predominate in some patients and should not be overlooked in determining an appropriate course of treatment . The empiric use of antibiotic therapy for ulcer patients without confirmation of the presence of H. pylori can not be recommended OBJECTIVES : There is an increasing interest in noninvasive tests for detecting Helicobacter pylori ( H. pylori ) infection . Unlike serological and urea breath tests , the possibility of search ing for H. pylori in feces has been scarcely investigated . The aim of this prospect i ve pilot study was to evaluate the usefulness of a new enzyme immunoassay for detecting H. pylori antigens in feces , as a predictor of H. pylori status in the pre- and posttreatment setting s. METHODS : One hundred and fifty-four symptomatic , anti-H. pylori untreated patients ( Group A ) and 116 anti-H. pylori treated patients ( Group B ) underwent gastroscopy with biopsies of the antrum and corpus for histology ( H ) and rapid urease test ( RUT ) . In the anti-H. pylori treated group , a 13C-urea breath test ( UBT ) was also performed . In Group A , H. pylori status was defined as positive or negative when both H and RUT gave concordant positive or negative results . In Group B , the patients were considered eradicated if all three tests were negative . A stool specimen was collected from all patients the day after gastroscopy , and tested by using an enzyme immunoassay commercial kit for detecting H. pylori antigens in feces ( HpSAT ) . RESULTS : Eighty-five patients in Group A ( 55 % ) and 44 in Group B ( 38 % ) were  H. pylori infected . On the whole , HpSAT showed a sensitivity of 94 % and specificity of 86 % . In Group 
    Output:
    
Additional confirmatory testing of positive or negative tests increased the diagnostic accuracy of the stool test , but had high incremental costs .
ELISA testing was preferable when prevalence rates were very high ( 90 % ) , and using a confirmatory urea breath test for negative ELISA tests increased the diagnostic accuracy to 96 % , with modest incremental costs .
If the cost of the breath test was < $ 50 or if the cost of the stool test is > $ 82 , breath testing became preferable to stool testing .
If the cost of the stool test fell to < $ 20 , it became preferable to ELISA .
Similarly , if the cost of the ELISA serology was > $ 39 then stool testing became preferable at all prevalence rates .
Fingerstick whole blood tests were not cost-effective .
CONCLUSIONS : The choice of an initial test for H. pylori detection depends on the prevalence of H. pylori infection and the value placed on increased diagnostic accuracy .
Although ELISA results in the lowest cost-effectiveness ratios , in patients at low-intermediate pretest probability of infection , the stool test provides increased accuracy , with modest incremental costs