bluuebunny/crossref_metadata_2025_split huggingface dataset:
Pretreatment Antibiotic Resistance inHelicobacter pyloriInfection: Results of Three Randomized Controlled Studies
Authors: Realdi Giuseppe , Dore Maria P. , Piana Andrea , Atzei Antonella , Carta Monica , Cugia Luigi , Manca Alessandra , Are Bianca M. , Massarelli Giovanni , Mura Ida , Maida Alessandro , Graham David Y. 
Published: March 2003

Background.Although combinations of antibiotics and antisecretory drugs are useful for treatment ofHelicobacter pyloriinfection, treatment failure is common. The aim of this study was to evaluate the relation between pretreatment antibiotic resistance and outcome by using six different treatment regimens forH. pyloriinfection.Patients and Methods.Three hundred sixty‐nine consecutiveH. pylori–infected patients with dyspeptic symptoms were enrolled in three consecutive randomized, controlled, single‐center clinical trials: trial A, 128 patients; trial B, 125 patients; trial C, 116 patients. Treatments consisted of (A) a 15‐day course of dual therapy (omeprazole, 20 mg bid, and amoxicillin, 1 gm bid, or clarithromycin, 500 mg tid) (OA vs OC); (B) a 7‐day triple therapy of omeprazole, 20 mg bid, plus metronidazole, 500 mg bid, and amoxicillin, 1,000 mg bid, or clarithromycin, 500 mg tid (OMA vs OMC); or (C) omeprazole, 20 mg bid, plus metronidazole, 500 mg bid, plus tetracycline, 500 mg qid, or doxycycline, 100 mg tid (OMT vs OMD). Diagnostic endoscopy was made in all patients before and 5 to 6 weeks after therapy. Six biopsies were taken from each patient for histology, rapid urease test, andH. pyloriculture; antibiotic susceptibility testing was performed using the E‐test method.Results.Overall cure rates were poor for both dual therapies OA and OC (38% and 37%, respectively) and for triple therapies OMA, OMC, and OMD (57%, 55%, and 58%, respectively). The OMT combination was successful in 91% (95% confidence interval [CI], 80.4%–97%). Metronidazole resistance was present in 29.7% (95% CI, 24%–35%), amoxicillin resistance was present in 26% (95% CI, 21%–32%), clarithromycin resistance was present in 23.1% (95% CI, 18%–29%), tetracycline resistance was present in 14% (95% CI, 10%–20%), and doxycycline resistance was present in 33.3% (95% CI, 21%–47%). Antibiotic resistance markedly reduced the cure rates and accounted for most of the poor results with the triple therapies: 89% versus 23%; 77% versus 26%; 100% versus 60%; and 67% versus 23% for OMC, OMA, OMT, and OMD, respectively. OMT appeared to be the best because of the high success rate with metronidazole‐resistantH. pylori(71%) and in low‐level tetracycline resistance.Conclusions.Pretreatment antibiotic‐resistantH. pylorican, in part, explain the low cure rate of the infection and the variability in outcome in reported trials.
Prevalence of Helicobacter pylori Resistance to Metronidazole, Clarithromycin, Amoxicillin, Tetracycline, and Furazolidone in Brazil
Authors: Mendonça Sergio , Ecclissato Christina , Sartori M.S. , Godoy Anita Paula Ortiz , Guerzoni Rosângela Aparecida , Degger Maristela , Pedrazzoli José 
Published: March 2003

Background. Helicobacter pylori infection is associated with a wide range of digestive diseases and is very prevalent in developing countries, although few data exist on the susceptibility of H. pylori to antimicrobials commonly used in eradication schedules in these countries. The aim of this study was to evaluate the resistance of H. pylori to metronidazole, clarithromycin, amoxicillin, tetracycline, and furazolidone in dyspeptic Brazilian patients.Material and Methods. Ninety consecutive H. pylori–positive patients were enrolled. Resistance was evaluated by an agar dilution test.Results. Resistance to metronidazole was detected in 38 patients (42%); to amoxicillin in 26 individuals (29%); to clarithromycin in 6 patients (7%); to tetracycline in 6 patients (7%); and to furazolidone in 4 individuals (4%). Thirteen strains were resistant to two agents, and eight strains were resistant to three antimicrobials.Conclusions. These results confirm the need for culture and susceptibility testing to define H. pylori resistance patterns in particular geographical areas before the general use of an eradication schedule. They also suggest the possibility of resistance to such antimicrobials as amoxicillin or tetracycline in geographical areas with a high prevalence of H. pylori infection and still not fully evaluated for antimicrobial susceptibility.
Clinical Usefulness of Urine‐based Enzyme‐linked Immunosorbent Assay for Detection of Antibody to Helicobacter pylori: A Collaborative Study in Nine Medical Institutions in Japan
Authors: Kato Mototsugu , Asaka Masahiro , Saito Masao , Sekine Hitoshi , Ohara Shuichi , Toyota Takayoshi , Akamatsu Taiji , Kaneko Taimei , Kiyosawa Kendo , Nishizawa Osamu , Kumagai Toshiko , Katsuyama Tsutomu , Abe Masahiro , Kosaka Masaaki , Hariya Shojiro , Minami Kunihiro , Sanai Yasuhiro , Sawamura Masayuki , Tachikawa Tetsuya 
Published: March 2003

Background. A urine‐based enzyme‐linked immunosorbent assay (ELISA) kit for detection of antibody to Helicobacter pylori has been developed in Japan. Urine samples can be obtained noninvasively and are easier and safer to handle than are serum samples. The aim of this study was to examine the clinical usefulness of this urine‐based ELISA kit.Materials and Methods. A pair of random, single‐void urine and serum samples was collected from each of 1,061 subjects, including 238 patients with gastroduodenal disease. The sensitivity and specificity of the urine‐based ELISA was compared with those of three commercially available serum‐based ELISA kits. For those patients with gastroduodenal disease, the urine‐ and serum‐based ELISA results were also compared with those for other diagnostic methods using endoscopic biopsy specimens, such as culture, histology, and rapid urease tests.Results. Based on the three serum‐based ELISA results, the sensitivity, specificity, and accuracy of the urine‐based ELISA were 97.7%, 95.6%, and 96.8%, respectively. On the basis of the biopsy test results, the sensitivity (96.2%), specificity (78.9%), and accuracy (91.0%) of the urine‐based ELISA were almost equivalent or superior to all three serum‐based ELISAs tested. In addition, 10 of the 12 false‐positive cases for urine‐based ELISA were confirmed to be true positives for antibodies to H. pylori by Western blot analysis and inhibition ELISA.Conclusions. The urine‐based ELISA (URINELISA H. pylori Antibody) is very accurate and should be useful as an alternative to serum‐based ELISAs for screening of H. pylori infection.
Circulating T‐Cell Response to Helicobacter pylori Infection in Chronic Gastritis
Authors: Ren Zhigang , Pang Gerald , Lee Roger , Batey Robert , Dunkley Margaret , Borody Tom , Clancy Robert 
Published: March 2003

Background. Helicobacter pylori elicits a specific humoral and cellular immune response. There is increasing evidence that the type of T‐cell response contributes to clinical outcome in H. pylori infection.Materials and Methods. The host response to H. pylori infection in 34 subjects with chronic gastritis was examined in terms of T‐cell proliferation and cytokine production in whole‐blood cultures stimulated or unstimulated with H. pylori acid‐glycine extract antigens (AGE).Results. The proliferative response in whole‐blood cultures was similar for both H. pylori–positive and –negative subjects stimulated with H. pylori AGE. While an increase in interferon‐γ (IFN‐γ) production was observed from both H. pylori–positive and –negative subjects with gastritis, significantly higher levels of IFN‐γ were detected in the former when stimulated with H. pylori AGE. In contrast, interleukin 4 (IL‐4) was undetectable regardless of antigen stimulation. However, if an in situ IL‐4 antibody capture assay was used, antigen‐independent production of IL‐4 was detected, but there was no difference between H. pylori–positive and –negative subjects with gastritis. After eradication of H. pylori, antigen‐induced production of IL‐4 was increased, with no decrease in the levels of secretion of IFN‐γ. IL‐4 production was dependent on CD4+ T cells, as addition of anti‐CD4 but not anti‐CD8 mouse monoclonal antibody or matched IgG isotype to the whole‐blood culture inhibited the production of IL‐4.Conclusion. The results suggest that a shift toward a balanced Th1‐Th2 response due to an increase in antigen‐induced IL‐4 production from CD4+ T cells follows eradication. We suggest that the downregulation of mucosal inflammation consequent on reduction in antigen levels or removal of downregulation after eradication of H. pylori contributes to this shift in cytokine balance.
Ranitidine Bismuth Citrate Can Help to Overcome Helicobacter pylori Resistance to Clarithromycin In Vivo
Authors: Mégraud Francis , Roberts Peter , Williamson Russell 
Published: March 2003

Background. Helicobacter pylori eradication usually fails when clarithromycin is used against resistant strains.Objective. The objective of this study was to test whether the apparent synergy found in vitro between ranitidine bismuth citrate (RBC) and clarithromycin also exists in vivo against resistant strains.Methods. H. pylori was cultured and clarithromycin susceptibility was determined before and after treatment, from duodenal ulcer patients receiving RBC and clarithromycin or omeprazole and clarithromycin for 2 weeks in a multicenter randomized clinical trial.Results. The overall eradication rate was 88.7% in the RBC group (71 patients) and 52.7% in the omeprazole group (74 patients). The demographic characteristics of the two groups were not different. Clarithromycin‐resistant strains were isolated in 22 cases (15.1%). A difference between the eradication rates of susceptible and resistant strains was found in the omeprazole group but not in the RBC group. After treatment, resistance to clarithromycin developed in three of the seven strains (42.3%) cultured from the patients of the RBC group, compared with 11 of the 26 strains (42%) of the omeprazole group. That is, clarithromycin‐resistant strains were found in 6% and 27% in the RBC group and the omeprazole group, respectively, on considering the global results.Conclusion. A synergy between RBC and clarithromycin may exist in vivo and, while clarithromycin resistance is increasing, it is an argument for using RBC in triple therapies.
The Accuracy of Serologic Diagnosis of Helicobacter pylori Infection in School‐aged Children of Mixed Ethnicity
Authors: Tindberg Ylva , Bengtsson Carina , Bergström Mats , Granström Marta 
Published: March 2003

AbstractThe present study evaluated two non‐invasive diagnostic methods for H. pylori infection in children, i.e. an in‐house ELISA using sonicated Campylobacter jejuni antigen for absorption of cross‐reacting antibodies and an immunoblot kit (Helico Blot 2.0, Genelabs, Singapore). 13C ‐Urea breath test (13C‐UBT) was used as reference method. Sera and questionnaires were collected from 695/858 (81%) Swedish school children with mixed ethnic backgrounds within a cross‐sectional, community‐based study. Of 133 children with an ELISA OD value of ≥ 0.1, all were screened with immunoblot and 107 made a 13C‐UBT. The negative controls were 34/37 children from three school classes with an ELISA OD value of < 0.1 and volunteering for a 13C‐UBT. An adjusted cut‐off level for the ELISA of OD value 0.22 resulted in a sensitivity of 97.8%, a specificity of 95.8% and a concordance index of 97.2%. The Helico Blot 2.0 had a sensitivity of 97.8%, a specificity of 93.8% and a concordance index of 96.5%. The best concordance was seen for the 26.5 kDa (98.6%), 30 kDa (95.7%) and 19.5 kDa (91.5%) antigens. The corresponding concordance index for CagA was 78%, for VacA 73.8% and for the 35kDa antigen 68.8%. A significant difference in the distribution of the 19.5 and 26.5 kDa bands but not of CagA/VacA was noted by ethnic background. With an adjusted cut‐off level for the enzyme‐linked immunosorbent assay (ELISA), both non‐invasive methods were found to have an adequate performance in a pediatric population. The differences in antibody response patterns by ethnic background represent a caveat in the interpretation of serological studies.
Helicobacter pylori and Early Duodenal Ulcer Status Post‐Treatment: a Review
Authors: Meyer Joette M. , Silliman Nancy P. , Dixon Cheryl A. , Siepman Nancy Y. , Sugg Jennifer E. , Hopkins Robert J. 
Published: March 2003

AbstractBackground.Data submitted to the FDA were reviewed to analyze the relationship between Helicobacter pylori infection and the incidence of early duodenal ulcers, within 6 weeks, following treatment.Materials and Methods.Retrospective analyzes were performed on data from three H. pylori development programs submitted to the FDA: ranitidine‐bismuth‐citrate (RBC), lansoprazole (L) and omeprazole (O). Efficacy assessments for the RBC, L and O programs were made at end of a 4‐week treatment period, 4–6 weeks following the end of a 14‐day treatment period, and 4 weeks following the end of a 4‐week treatment period, respectively.Results.Overall, there was a 15%, 21% and 23% decrease in the number of patients in the RBC, L and O programs, respectively, with ulcers among H. pylori cleared/eradicated patients post‐treatment compared with patients with persistent infection. Among patients who did not have cleared/eradicated H. pylori in the RBC and O programs, where antisecretory agents were continued beyond the antimicrobial treatment period, the number of ulcers was lower in the antisecretory plus antimicrobial subgroups compared with the antimicrobial alone subgroups (37% vs. 46% for RBC and 33% vs. 42% for O). Among patients with cleared/eradicated H. pylori, the number of patients with ulcers in the antimicrobial alone subgroups and antisecretory plus antimicrobial subgroups were similar within each program. Antimicrobials alone had significantly lower rates of ulcers among patients with cleared/eradicated H. pylori as compared with patients without clearance/eradication.Conclusions.The early incidence of duodenal ulcers is significantly decreased in patients with H. pylori clearance/eradication.
Interactions Among Gastric Somatostatin, Interleukin‐8 and Mucosal Inflammation in Helicobacter pylori‐Positive Peptic Ulcer Patients
Authors: Yamamoto Sayuri , Kaneko Hiroshi , Konagaya Toshihiro , Mori Shozaburo , Kotera Hiroshi , Hayakawa Toshihiko , Yamaguchi Chikara , Uruma Motoaki , Kusugami Kazuo , Mitsuma Terunori 
Published: March 2003

ABSTRACTBackground. To investigate whether Helicobacter pylori infection, but not drugs, affects gastric somatostatin, interleukin‐8 (IL‐8), histological inflammation through eradication therapy, and interactions among these parameters.Methods. Twenty‐eight H. pylori‐positive patients (21 males; mean age 47.0 years) with either gastric ulcer (GU: n = 11) or duodenal ulcer (n = 17) diagnosed endoscopically were treated with dual therapy. Eradication was defined as negative microbiologic tests and 13C‐urea breath test. Levels of antral and gastric juice somatostatin and mucosal IL‐8 were measured by radioimmunoassay and enzyme‐linked immunosorbent assay, respectively. Histology was assessed by the Sydney system.Results.  H. pylori was eradicated in 15 patients (10 males, 6 GU) out of 28 (54%). The patients’ backgrounds did not affect the eradication of H. pylori. Successes in eradication significantly increased antral and juice somatostatin contents, and dramatically decreased IL‐8 levels and histological gastritis. In contrast, persistent H. pylori infection did not affect somatostatin and histological gastritis. An inverse correlation was present between changes in somatostatin levels and histological activity. No relationship was observed in changed values between antral somatostatin and IL‐8.Conclusions.  These results indicate that eradication of H. pylori, but not the drugs used, induced an increase in somatostatin levels in the antrum and gastric juice, suggesting a close relationship between H. pylori and gastric somatostatin regulation. A close correlation between an increase in gastric somatostatin levels and the normalization of histological activity was present, suggesting that certain peptide‐immune interactions in the gastric mucosa exist in H. pylori infection.
Distribution of Distinct vacA, cagA and iceA Alleles in Helicobacter pylori in Hong Kong
Authors: Wong Benjamin Chun Yu , Yin Yan , Berg Douglas E. , Xia Harry Hua‐Xiang , Zhang Jian Zhong , Wang Wei Hong , Wong Wai Man , Huang Xiao Ru , Tang Vera Shun Yim , Lam Shiu Kum 
Published: March 2003

ABSTRACTBackground.There is a substantial genetic heterogeneity among Helicobacter pylori strains, and certain genotypes have been suggested to be associated with the virulence of this pathogen. The aim of this study was to investigate the distribution of H. pylori vacA, cagA and iceA genotypes and their association with duodenal ulcer disease in Hong Kong.Materials and Methods.Gastric biopsies of 72 H. pylori infected patients were analyzed by specific polymerase chain reactions.Results.Of the 72 cases, 69 (95.8%) had vacA signal sequence s1c strains, and three (4.2%) had s1a strains. vacA middle region sequences, m1b and m2, were detected in 23 (31.9%) and 46 (63.9%), respectively. Six (8.3%) cases contained multiple vacA subtypes. vacA s2 allele was only observed in three (4.3%) cases, which were also infected with s1c subtype. cagA was present in 64 (88.9%) of 72 patients, and iceA1 subtype was detected in 46 (63.9%) cases. Neither cagA nor vacA and iceA were associated with duodenal ulcer disease.Conclusion.The distribution of vacA, cagA and iceA alleles in H. pylori strains in Hong Kong is similar to that in east Asia. There is a difference in the distribution of genotypes between strains in Hong Kong and those in mainland China, although strains in the two regions exhibit a very close relation. The association of these virulence genes and duodenal ulcer disease needs reappraisal, particularly under geographic considerations.
The Effects of Nocturnal Acid Breakthrough on Helicobacter pylori Eradication
Authors: Il Kim Jin , Park Soo‐Heon , Kwang Kim Jae , Sik Chung In , Won Chung Kyu , Sik Sun Hee 
Published: March 2003

ABSTRACTBackground. The effects of nocturnal gastric acid breakthrough (NAB) on Helicobacter pylori eradication are still unknown in peptic ulcer patients. The purposes of this study were to compare the effect of lansoprazole 30 mg twice a day (bid) to lansoprazole 60 mg once a day (qd) on the prevalence of NAB, and to determine whether NAB affects the eradication of H. pylori in peptic ulcer patients.Methods.  Experiments were carried out in 67 patients with H. pylori‐positive peptic ulcers. They were randomized into two groups, one treated with a combination of lansoprazole 60 mg, clarithromycin 1.0 g, and amoxycillin 2.0 g once a day before breakfast (qd group), and the other, divided doses of the drugs were given before breakfast and dinner (bid group) for 2 weeks.Results.  NAB occurred in 31 patients, 55.2% in qd group, and 39.5% in bid group (p = .226). H. pylori eradication was achieved in 61.3% in NAB positive group and 83.3% in NAB negative group (p = .055). The mean duration of NAB for H. pylori eradication group was 99.3 ± 22.7 min, and 293.2 ± 49.8 min for H. pylori persistence group (p < .05). The median intragastric pH of the H. pylori eradication and persistence group was 5.7 ± 0.2 and 4.2 ± 0.4, respectively (p < .05).Conclusions.  Neither the morning dose and the divided dose regimen of lansoprazole affected the intragastric acidity and occurrence of the NAB. NAB did not influence H. pylori eradication in peptic ulcer patients, but the duration of NAB and total intragastric median pH were found to influence the H. pylori eradication.
Oxidative Stress in Gastric Mucosa of Asymptomatic Humans Infected with Helicobacter pylori: Effect of Bacterial Eradication
Authors: Felley C. P. , Pignatelli B. , Van Melle G. D. , Crabtree J. E. , Stolte M. , Diezi J. , Corthesy‐Theulaz I. , Michetti P. , Bancel B. , Patricot L. M. , Ohshima H. , Felley‐Bosco E. 
Published: March 2003

ABSTRACTBackground. Inducible nitric oxide synthase (iNOS) and interleukin 8 (IL‐8) are positive in approximately 50% of Helicobacter pylori‐related diseases but it is not clear whether oxidative stress is also present in H. pylori asymptomatic humans. Our aim was to study the expression of iNOS, superoxide dismutase, catalase and IL‐8 production in H. pylori‐infected asymptomatic humans, and to investigate the effect of eradication of H. pylori.Materials and Methods. Biopsies of corpus and antrum of asymptomatic H. pylori positive and negative humans served for determination of the gastritis score and H. pylori status; iNOS was measured by reverse transcriptase polymerase chain reaction and immunohistochemistry and superoxide dismutase and catalase by immunohistochemistry. IL‐8 in biopsies was assessed by enzyme‐linked immunosorbent assay.Results. Immunostaining of iNOS, catalase and superoxide dismutase was significantly associated with H. pylori infection and was localized to inflammatory cells. IL‐8 concentrations were greater in the H. pylori positive than H. pylori negative group and decreased after bacterial eradication. A decrease in staining for iNOS and catalase was observed after H. pylori eradication.Conclusions. INOS and antioxidant enzymes are present in gastric biopsies of asymptomatic H. pylori positive humans. Eradication caused a significant decrease in staining for iNOS and catalase. These results indicate that oxidative stress occurs in asymptomatic patients and can be modulated by H. pylori eradication.
Clinical Application of 20 MHz Endosonography and Anti‐Helicobacter pylori Immunoblots to Predict Regression of Low‐grade Gastric MALToma by H. pylori Eradication
Authors: Sheu Bor‐Shyang , Shiesh Shu‐Chu , Wang Jin‐Town , Yang Hsiao‐Bai , Lin Shih‐Ting , Wu Jiunn‐Jong 
Published: March 2003

ABSTRACTAim. We tested whether serial 20 MHz endosonography (EUS) and anti‐Helicobacter pylori immunoblots can predict the complete regression of gastric MALToma by H. pylori eradication.Methods. The serums of 17 MALToma patients, including 15 with low grade and two with high grade, were collected before therapy. Fifteen patients with low‐grade MALToma and 18 nonMALToma patients, all infected with H. pylori, have been followed with serum sampling, endoscopy, and EUS on enrollment, on the 2nd, 6th, and 12th months after anti‐H. pylori therapy. All sera were tested for anti‐H. pylori immunoblots, including 19.5, 26.5, 30, 35, 89, 116 KDa (CagA), FldA. The DNAs were extracted serially from the biopsy of MALToma patients before and after therapy to perform polymerase chain reaction (PCR) for the immunoglobulin heavy‐chain gene monoclonality.Results. MALToma patients had higher prevalence rates of anti‐FldA protein, 19.5 and 30 KDa antibodies of H. pylori (p < 0.01). After H. pylori eradication, MALToma patients had negative seroconversion of 19.5, 26.5, 30, and 35 KDa antibodies (p < 0.05), but not in CagA and FldA. The PCR monoclonality occurred in 80% (12/15) of the MALToma patients before therapy, but did not correlate with any seroconversion of anti‐H. pylori immunoblots after therapy (p > 0.05). Complete regression of MALToma was observed in 73.3% (11/15) of patients. Evaluation with 20 MHz EUS, for the initial tumor depth and its normalization on the 6th month had 90.9% sensitivity and 100% specificity to predict the complete regression.Discussion. The negative seroconversions of the smaller‐molecular‐weight proteins, but not CagA and FldA, correlate with regression of MALToma by H. pylori eradication. 20 MHz EUS can effectively predict the therapeutic response of MALToma.