Eradication of gastric cancer is now both possible and practical

In 1994, Helicobacter pylori was declared a human carcinogen. Evidence has now accumulated to show that at least 95% of gastric cancers are etiologically related to H. pylori. An extensive literature regarding atrophic gastritis and its effects on acid secretion, gastric microflora, and its tight association with gastric cancer has been rediscovered, confirmed, and expanded. Methods to stratify cancer risk based on endoscopic and histologic findings or serologic testing of pepsinogen levels and H. pylori testing have been developed producing practical primary and secondary gastric cancer prevention strategies. H. pylori eradication halts progressive mucosal damage. Cure of the infection in those with non-atrophic gastritis will essentially prevent subsequent development of gastric cancer. For all, the age-related progression in cancer risk is halted and likely reduced as eradication reduces or eliminates mucosal inflammation and reverses or reduces H. pylori-associated molecular events such aberrant activation-induced cytidine deaminase expression, double strand DNA breaks, impaired DNA mismatch repair and aberrant DNA methylation. Those who have developed atrophic gastritis/gastric atrophy however retain some residual risk for gastric cancer which is proportional to the extent and severity of atrophic gastritis. Primary and secondary cancer prevention starts with H. pylori eradication and cancer risk stratification to identify those at higher risk who should also be considered for secondary cancer prevention programs. Japan has embarked on population-wide H. pylori eradication coupled with surveillance targeted to those with significant remaining risk. We anticipate that countries with high gastric cancer burdens will follow their lead. We provide specific recommendations on instituting practical primary and secondary gastric cancer prevention programs as well identifying research needed to make elimination of gastric cancer both efficient and cost effective.

Toothpick perforation of the intestines presenting as recurrent abdominal pain: possible roles of abdominal ultrasound and MRI

We report the case of a middle-aged man admitted for five months of unexplained left lower quadrant pain. He had been hospitalized on two prior occasions and treated with broad spectrum antibiotics. His clinical presentation was suggestive peritoneal irritation with severe, focal pain on abdominal palpation. Computed tomography scans showed non-specific inflammation in the left lower abdomen with adjacent small bowel wall thickening. Upper endoscopy and colonoscopy were unremarkable on prior admission. Given the severity and focality of the patient’s recurrent abdominal pain he underwent laparoscopy and was found to have a wooden toothpick perforation of the small bowel thirty centimeters from the ileocecal valve requiring partial small bowel resection. The patient did well post-operatively. On retrospective questioning he may have eaten a cabbage roll or bacon wrapped shrimp pierced with a toothpick weeks before the onset of symptoms. Toothpick perforation should be a consideration in edentulous persons with focal, severe abdominal pain and trans-abdominal ultrasound or MRI may be a better choice for detecting wooden foreign objects.

Esophageal squamous cell carcinoma with special reference to its early stage

The term 'early squamous cell carcinoma of the oesophagus', which was previously restricted to superficial carcinoma with no lymph node metastasis, now encompasses intramucosal carcinoma regardless of the nodal status. Such lesions are rare in Western countries, where the experience is limited. In recent years, the development and greater use of chromoendoscopy and narrow band imaging (NBI), both of which facilitate the evaluation of mucosal morphology, have played an important role in the detection of early esophageal squamous cell carcinoma. In addition, the techniques and indications of endoscopic resection (mucosal resection [EMR] and mucosal dissection [ESD]) are still being refined. In the present article, we will discuss the clinical and pathologic features of esophageal early squamous cell carcinoma, as well as the epidemiology and aetiology of esophageal cancer in general. In addition, we will provide a therapeutic decision tree taking into account endoscopic and surgical modalities as they apply to early esophageal squamous cell carcinoma.

Towards understanding the low prevalence of Helicobacter pylori in Malays: genetic variants among Helicobacter pylori-negative ethnic Malays in the north-eastern region of Peninsular Malaysia and Han Chinese and South Indians

OBJECTIVES

To identify gene polymorphisms that differ between Malays, Han Chinese and South Indians, and to identify candidate genes for the investigation of their role in protecting Malays from Helicobacter pylori (H. pylori) infection.

METHODS

Malay participants born and residing in Kelantan with a documented absence of H. pylori infection were studied. Venous blood was used for genotyping using the Affymetrix 50K Xba I kit. CEL files from 141 Han Chinese and 76 South Indians were analyzed to compare their allele frequency with that of the Malays using fixation index (FST ) calculation. The single nucleotide polymorphisms (SNPs) with the highest allele frequency (outliers) were then examined for their functional characteristics using F-SNP software and the Entrez Gene database.

RESULTS

In all, 37 Malays were enrolled in the study; of whom 7 were excluded for low genotyping call rates. The average FST estimated from the genome-wide data were 0.038 (Malays in Kelantan vs the South Indians), 0.015 (Malays in Kelantan vs Han Chinese) and 0.066 (Han Chinese vs South Indians), respectively. The outlier gene variants present in Malays with functional characteristics were C7orf10 (FST  0.29988), TSTD2 (FST  0.43278), SMG7 (FST  0.29877) and XPA (FST  0.43393 and 0.43644).

CONCLUSION

Genetic variants possibly related to protection against H. pylori infection in ethnic Malays from the north-eastern region of Peninsular Malaysia were identified for testing in subsequent trials among infected and uninfected Malays.

PCR detection of Helicobacter pylori in clinical samples

Helicobacter pylori is an important pathogen whose primary niche is the human stomach. H. pylori is etiologically associated with gastric inflammation (gastritis), peptic ulcer disease, and gastric cancer. Both noninvasive (e.g., urea breath and stool antigen tests) and invasive (gastric biopsy for histology, culture, or PCR) tests are used for diagnosis. PCR detection of H. pylori has been reported using a variety of clinical samples including gastric biopsy, gastric juice, saliva, dental plaque, and stools as well as environmental samples. Whenever possibly, noninvasive tests are preferred over invasive tests. H. pylori are excreted in the stool. Culture from stool is variable whereas stool antigen testing is widely used. Stool consists of a complicated mixture of commensal bacteria and chemicals and often includes inhibitors of PCR. Nevertheless, simple extraction methods are available to efficiently extract DNA from human stools and nested-PCR targeting the 23S rRNA gene have proven to be highly sensitive for the detection of H. pylori. Detection of clarithromycin susceptibility/resistance is important clinically and the mutation of the 23S rRNA gene responsible for resistance can also be detected using stool. This described method can be modified for other clinical samples such as gastric juice or biopsy material.

Gastrointestinal symptoms and Helicobacter pylori infection in school-age children residing in Porto Torres, Sardinia, Italy

BACKGROUND

Helicobacter pylori infection is typically acquired in childhood, and following the acute event, it is thought that most infections remain asymptomatic. H. pylori has been suggested to protect against diarrhea in childhood.

AIM

To examine the role of H. pylori in gastrointestinal symptoms in children.

MATERIALS AND METHODS

A cross-sectional sero-epidemiologic study was conducted in Porto Torres, Sardinia, Italy. Demographic information, socioeconomic factors, and the frequency of upper gastrointestinal symptoms during the previous 3 months (e.g., abdominal pain, diarrhea, nausea, heartburn, halitosis, slow digestion, belching, and weight loss) were evaluated by a questionnaire. H. pylori status was determined by ELISA.

RESULTS

Approximately 95% (N = 1741) of school children between the age of 6 and 15 years from Porto Torres participated. The sero-prevalence of H. pylori infection was 13.3% (229/1727) and similar in boys (13%) and girls (14%) (p = .57). Nausea/vomiting (odds ratio (OR) = 2.2 (95% CI = 1.2-5.1)) and diarrhea (OR = 2.1 (95% CI = 1.3-2.8)) were each significantly associated with H. pylori infection, and these associations remained significant after controlling for other study variables. There was no significant association between H. pylori and abdominal pain or heartburn (p > .25).

CONCLUSIONS

The study does not support either a role of H. pylori infection in abdominal pain in children or a protective role against diarrheal illnesses or nausea/vomiting.

Greater than 95% success with 14-day bismuth quadruple anti- Helicobacter pylori therapy: a pilot study in US Hispanics

BACKGROUND

A combination capsule of bismuth, metronidazole, and tetracycline plus omeprazole given as 10-day therapy has an overall effectiveness of 92-93% in per-protocol analysis (Grade B) with eradication of 86-91% of metronidazole-resistant Helicobacter pylori. This study aimed to explore whether extending the duration to 14 days would improve overall effectiveness per protocol to ≥95% (Grade A) in a population in which metronidazole resistance was anticipated to exist.

METHODS

A one-arm, open-label pilot study of H. pylori-infected, asymptomatic/mildly dyspeptic adults, Hispanic residents of El Paso, Texas, received a 14-day course of omeprazole, plus the combination capsule. We cultured and Gram-stained specimens obtained using a minimally invasive orogastric brush. Helicobacter pylori status was determined by (13)C-urea breath test at 4 or more weeks post-therapy.

RESULTS

Forty-seven subjects (7 men and 40 women, average age 42 years) were entered. The per-protocol effectiveness was 97.1% (33/34) (95% mid-P CI: 86.3, 99.9); 100% of metronidazole-resistant strains were eradicated. Side effects were mild and self-limited but contributed to nonadherence. Therapy taken for <10 days was more likely to result in eradication failure (p < .001). Office-based orogastric brushing was well tolerated; positive cultures were obtained in 95%. Gram staining showed H. pylori-like forms in all specimens.

CONCLUSIONS

This pilot study supports the concept that 14-day OBMT therapy is likely to be more efficacious for H. pylori eradication (Grade A, PP basis) than a 10-day course where metronidazole resistance is suspected. If confirmed, 14 days should be recommended in populations where metronidazole resistance is common.

Greater than 95% success with 14-day bismuth quadruple anti- Helicobacter pylori therapy: a pilot study in US Hispanics

BACKGROUND

A combination capsule of bismuth, metronidazole, and tetracycline plus omeprazole given as 10-day therapy has an overall effectiveness of 92-93% in per-protocol analysis (Grade B) with eradication of 86-91% of metronidazole-resistant Helicobacter pylori. This study aimed to explore whether extending the duration to 14 days would improve overall effectiveness per protocol to ≥95% (Grade A) in a population in which metronidazole resistance was anticipated to exist.

METHODS

A one-arm, open-label pilot study of H. pylori-infected, asymptomatic/mildly dyspeptic adults, Hispanic residents of El Paso, Texas, received a 14-day course of omeprazole, plus the combination capsule. We cultured and Gram-stained specimens obtained using a minimally invasive orogastric brush. Helicobacter pylori status was determined by (13)C-urea breath test at 4 or more weeks post-therapy.

RESULTS

Forty-seven subjects (7 men and 40 women, average age 42 years) were entered. The per-protocol effectiveness was 97.1% (33/34) (95% mid-P CI: 86.3, 99.9); 100% of metronidazole-resistant strains were eradicated. Side effects were mild and self-limited but contributed to nonadherence. Therapy taken for <10 days was more likely to result in eradication failure (p < .001). Office-based orogastric brushing was well tolerated; positive cultures were obtained in 95%. Gram staining showed H. pylori-like forms in all specimens.

CONCLUSIONS

This pilot study supports the concept that 14-day OBMT therapy is likely to be more efficacious for H. pylori eradication (Grade A, PP basis) than a 10-day course where metronidazole resistance is suspected. If confirmed, 14 days should be recommended in populations where metronidazole resistance is common.

Circulating tumor cells in the diagnosis and management of pancreatic cancer

Pancreatic cancers are typically resistant to chemo and radiation therapy and are predisposed to distant metastases. Circulating tumor cells (CTCs) are tumor cells disseminated from primary and metastatic sites and can be isolated from peripheral blood. CTC may overcome the limitation of the current available tumor markers, CA19-9. As a surrogate for 'real-time biopsy', CTCs allow recurrent assessment of a tumor's biological activity. We review the current methodologies for CTC extraction and characterization including antibody-based immunological assays, PCR-based assays, and novel technologies based on the physical or biological characteristics of CTCs. CTCs also provide an accessible link to the existence of epithelial to mesenchymal transition, tumor stem cell markers, and ongoing clonal mutations and epigenetic changes in the tumor. We also explore the potential of using CTC profiling in diagnosis, selection of neoadjuvant and adjuvant therapy, detection of recurrent disease, examination of pharmacodynamic biomarkers, as well as in gene therapy and immunotherapy for pancreatic cancer. Ongoing CTC characterization not only has the potential to represent all cells shed from primary pancreatic tumor and each metastatic site, but also allows dynamic sampling at multiple time points during the clinical course to identify the subpopulations of CTCs and the specific molecules driving metastasis and chemo resistance. We predict that CTC genotyping and phenotyping will play an increasing role in personalized therapy and in identification of novel therapeutic targets as well as monitoring the course and status of the disease.

Helicobacter pylori-associated regulation of forkhead transcription factors FoxO1/3a in human gastric cells

BACKGROUND

Interaction of Helicobacter pylori with gastric mucosa leads to marked cellular and humoral host immunologic responses. The signaling pathways initiated by bacteria-host interaction that result in perturbations in cell structure and function remain unclear. Forkhead transcription factors of class O (FoxO) are implicated in the regulation of apoptosis, cell survival, and pathogenesis. H. pylori infection of gastric epithelial cells induces phosphoinositide-3 kinase (PI3K)-dependent Akt activation and cell survival signaling. We investigated the role of H. pylori-activated PI3K/Akt in the regulation of FoxO1/3a in gastric cells.

METHODS

Immunoblot, immunoprecipitation, and fluorescence microscopy were used to assess the effect of infection of gastric epithelial cells with wild-type H. pylori and their isogenic cag pathogenicity island (PAI) or oipA mutants on the FoxO1/3a signaling pathways. Interleukin-8 release was determined by enzyme-linked immunosorbent assays.

RESULTS

 H. pylori infection resulted in activation of the PI3K p85 subunit and inactivation of FoxO1 and FoxO3a by their phosphorylation and translocation of from the nucleus to the cytoplasm. Inhibition of PI3K or Akt kinase activity reduced FoxO1/3a phosphorylation. Akt, FoxO1, or FoxO3a siRNA reduced H. pylori-induced interleukin-8 production. Infection with oipA mutants reduced PI3K/Akt activation and inhibited FoxO1/3a phosphorylation, whereas infection with cag PAI mutants reduced PI3K/Akt activity but did not inhibit FoxO1/3a activation.

CONCLUSIONS

FoxO1 and FoxO3a are novel nuclear substrates of H. pylori-induced PI3K/Akt cell survival signaling pathways that partially control interleukin-8 production. OipA-regulated interleukin-8 release through PI3K/Akt is dependent on FoxO1/3a inactivation, whereas cag PAI-mediated interleukin-8 production employs FoxO1/3-independent signaling.

Management of Helicobacter pylori infection--the Maastricht IV/ Florence Consensus Report

Management of Helicobacter pylori infection is evolving and in this 4th edition of the Maastricht consensus report aspects related to the clinical role of H pylori were looked at again in 2010. In the 4th Maastricht/Florence Consensus Conference 44 experts from 24 countries took active part and examined key clinical aspects in three subdivided workshops: (1) Indications and contraindications for diagnosis and treatment, focusing on dyspepsia, non-steroidal anti-inflammatory drugs or aspirin use, gastro-oesophageal reflux disease and extraintestinal manifestations of the infection. (2) Diagnostic tests and treatment of infection. (3) Prevention of gastric cancer and other complications. The results of the individual workshops were submitted to a final consensus voting to all participants. Recommendations are provided on the basis of the best current evidence and plausibility to guide doctors involved in the management of this infection associated with various clinical conditions.

Sociocultural and dietary practices among Malay subjects in the north-eastern region of Peninsular Malaysia: a region of low prevalence of Helicobacter pylori infection

BACKGROUND AND AIM

The prevalence of Helicobacter pylori infection is exceptionally low among the Malays in the north-eastern region of Peninsular Malaysia. The reasons are unknown. Our aim was to compare environmental factors that differed in relation to H. pylori prevalence among Malays born and residing in Kelantan.

METHODS

A case-control study was conducted among Malays in Kelantan who underwent upper endoscopy between 2000 and 2008. Helicobacter pylori status was determined by gastric histology. Sociocultural and dietary factors were assessed using a validated investigator-directed questionnaire administered after 2008, and the data were analyzed using logistic regression analysis.

RESULTS

The study group consisted of 161 subjects (79 H. pylori positive and 82 controls). Univariable analysis identified five poor sanitary practices associated with an increased prevalence of H. pylori infection: use of well water, use of pit latrine, less frequent boiling of drinking water, and infrequent hand wash practice after toilet use and before meals. Multivariable logistic regression analysis identified three variables inversely associated with H. pylori infection: frequent consumption of tea (OR: 0.023, 95% CI: 0.01-0.07), frequent use of "budu" or local anchovy sauce (OR: 0.09, 95% CI: 0.1-0.7), and frequent use of "pegaga" or centenella asiatica (OR: 0.25, 95% CI: 0.1-0.65).

CONCLUSIONS

Under the assumption that sanitary, sociocultural, and dietary habits have not changed over the years, we can conclude that an increased risk of H. pylori was associated with unsanitary practices whereas protection was associated with consumption of tea and locally produced foods, "pegaga" and "budu." These dietary factors are candidates for future study on the effects on H. pylori transmission.

Increasing the duration of dual amoxicillin plus omeprazole Helicobacter pylori eradication to 6 weeks: a pilot study

BACKGROUND AND AIM

Helicobacter pylori infections have become increasingly difficult to treat as antimicrobial resistance has increased. The aim of this study was to test the hypothesis that a 6-week dual regimen of amoxicillin 1 gm and omeprazole 20 gm therapy b.i.d. would cure at least 90% of treatment-naïve H. pylori infections.

METHODS

This was an open-label prospective pilot study in which treatment-naïve subjects with active H. pylori infection (positive by two tests) received dual amoxicillin 1 g and omeprazole 20 mg, b.i.d. daily for 6 weeks. Success was accessed by urea breath test 4-6 weeks later. A tentatively effective therapy was defined as a per-protocol treatment success of 90% or greater; treatment success of 80% or less was prespecified as unacceptable.

RESULTS

Sixteen patients were included in the study (14 men, two women) with an average age of 49 years. At 16 patients, the prespecified stopping rule of six treatment failures was achieved (i.e. the 95% confidence interval excluded achieving the required 90% success rate even if 50 patients were entered). As per protocol, enrollment was stopped. Per-protocol and intention-to-treat treatment success were both 62.5% (95% confidence interval, 35-84%). Compliance was greater than 99%. Five patients (31%) reported side-effects, all of which were mild and none interrupted therapy.

CONCLUSION

Despite the theory and pre-existing data from Japan, in the USA, prolonging the duration of dual amoxicillin-PPI therapy did not improve treatment outcome in 90% or more of our patients.

In vitro and in vivo protection against indomethacin-induced small intestinal injury by proton pump inhibitors, acid pump antagonists, or indomethacin-phosphatidylcholine

BACKGROUND/AIMS

Proton pump inhibitors (PPIs) are widely used to prevent nonsteroidal anti-inflammatory drug (NSAID)-induced peptic ulcers. NSAIDs produce small intestinal injury and some PPIs have been reported to protect against NSAID-induced small bowel injury in rats. The aim of this study was to compare PPIs, revaprazan, and phosphatidylcholine-associated indomethacin (Indo-PC) for protection against indomethacin (Indo)-induced small bowel injury.

METHODS

Rat intestinal epithelial cells (IEC-6) were pretreated with omeprazole, lansoprazole, or revaprazan prior to exposure to Indo or Indo-PC. Cell viability was assessed by methyl thiazolyl tetrazolium assay. Omeprazole, lansoprazole, or revaprazan was administered orally to rats prior to the vehicle or Indo. Indo-PC was administered alone. After 24 h, small intestinal erosions were counted; intestinal bleeding was assessed as the hemoglobin concentration of small intestinal fluid.

RESULTS

Omeprazole, lansoprazole, and revaprazan did not protect against Indo-induced IEC-6 cell injury. Indo-PC was less damaging in vitro than Indo alone. In vivo, neither omeprazole nor lansoprazole protected against Indo-induced small bowel injury; however, revaprazan pretreatment and Indo-PC resulted in significantly fewer erosions (>50% reduction) or bleeding (>80% reduction).

CONCLUSION

PPIs showed no small bowel protective effect in vitro or in vivo. Revaprazan showed a small bowel protective effect in vivo, whereas Indo-PC was protective both in vitro and in vivo.

Helicobacter pylori Therapy in the West

Increasing antimicrobial resistance has continued to plague successful anti-Helicobacter pylori eradication therapy. With rare exception, clarithromycin-containing triple therapy now provides unacceptably low treatment success. Here we discuss the factors that influence treatment outcome, how to predict outcome with new regimens, the 4-drug regimens that are currently effective in the West and their limitations, considerations about the approach to treatment failures and finally, based on the experience in the West, provide recommendations for choosing an empiric regimen in Japan. The dictum "use what works best locally" is probably the best advice for clinicians with a corollary that this dictum overrides results published by consensus conferences and advice from experts from elsewhere.

Norovirus vaccine against experimental human Norwalk Virus illness

BACKGROUND

Noroviruses cause epidemic and sporadic acute gastroenteritis. No vaccine is available to prevent norovirus illness or infection.

METHODS

We conducted a randomized, double-blind, placebo-controlled, multicenter trial to assess the safety, immunogenicity, and efficacy of an investigational, intranasally delivered norovirus viruslike particle (VLP) vaccine (with chitosan and monophosphoryl lipid A as adjuvants) to prevent acute viral gastroenteritis after challenge with a homologous viral strain, Norwalk virus (genotype GI.1). Healthy adults 18 to 50 years of age received two doses of either vaccine or placebo and were subsequently inoculated with Norwalk virus and monitored for infection and gastroenteritis symptoms.

RESULTS

Ninety-eight persons were enrolled and randomly assigned to receive vaccine (50 participants) or placebo (48 participants), and 90 received both doses (47 participants in the vaccine group and 43 in the placebo group). The most commonly reported symptoms after vaccination were nasal stuffiness, nasal discharge, and sneezing. Adverse events occurred with similar frequency among vaccine and placebo recipients. A Norwalk virus-specific IgA seroresponse (defined as an increase by a factor of 4 in serum antibody levels) was detected in 70% of vaccine recipients. Seventy-seven of 84 participants inoculated with Norwalk virus were included in the per-protocol analysis. Vaccination significantly reduced the frequencies of Norwalk virus gastroenteritis (occurring in 69% of placebo recipients vs. 37% of vaccine recipients, P=0.006) and Norwalk virus infection (82% of placebo recipients vs. 61% of vaccine recipients, P=0.05).

CONCLUSIONS

This norovirus VLP vaccine provides protection against illness and infection after challenge with a homologous virus. (Funded by LigoCyte Pharmaceuticals and the National Institutes of Health; ClinicalTrials.gov number, NCT00973284.).

The Role of CD44 in the Pathogenesis, Diagnosis, and Therapy of Gastric Cancer

CD44 is a transmembrane glycoprotein and surface receptor for hyaluronan that is involved in the response of cells to their microenvironment. CD44 splice variants play roles in carcinogenesis, differentiation, and lymph node metastasis and are predictive of the prognosis for various carcinomas, including gastric cancer. Current data suggest that gastric tissue stem cells and gastric cancer stem cells both express the splice variant, CD44v9. Overall, the data regarding the alterations that occur in CD44 and its splice variants in response to acute and chronic infection with Helicobacter pylori are scant and poorly elucidated in terms of possible changes in expression that occur in gastric cancer precursor lesions, such as chronic atrophic gastritis, pyloric metaplasia and intestinal metaplasia. In this study, we discuss the available data and suggest which new data would likely be useful in clinical practice. We also discuss the potential for CD44-targeted therapeutic strategies in gastric cancer. CD44 and its splice variants are positively associated with the initiation and progression of gastric cancer and may also play important roles in diagnosis, therapy and prognosis. CD44 research has been active but fragmented, and it may offer new therapeutic approaches to gastric cancer.

The Role of CD44 in the Pathogenesis, Diagnosis, and Therapy of Gastric Cancer

CD44 is a transmembrane glycoprotein and surface receptor for hyaluronan that is involved in the response of cells to their microenvironment. CD44 splice variants play roles in carcinogenesis, differentiation, and lymph node metastasis and are predictive of the prognosis for various carcinomas, including gastric cancer. Current data suggest that gastric tissue stem cells and gastric cancer stem cells both express the splice variant, CD44v9. Overall, the data regarding the alterations that occur in CD44 and its splice variants in response to acute and chronic infection with Helicobacter pylori are scant and poorly elucidated in terms of possible changes in expression that occur in gastric cancer precursor lesions, such as chronic atrophic gastritis, pyloric metaplasia and intestinal metaplasia. In this study, we discuss the available data and suggest which new data would likely be useful in clinical practice. We also discuss the potential for CD44-targeted therapeutic strategies in gastric cancer. CD44 and its splice variants are positively associated with the initiation and progression of gastric cancer and may also play important roles in diagnosis, therapy and prognosis. CD44 research has been active but fragmented, and it may offer new therapeutic approaches to gastric cancer.

Operative link for gastritis assessment vs operative link on intestinal metaplasia assessment

AIM: To compare the reliability of gastritis staging systems in ranking gastritis-associated cancer risk in a large series of consecutive patients.

METHODS: Gastric mucosal atrophy is the precancerous condition in which intestinal-type gastric cancer (GC) most frequently develops. The operative link for gastritis assessment (OLGA) staging system ranks the GC risk according to both the topography and the severity of gastric atrophy (as assessed histologically on the basis of the Sydney protocol for gastric mucosal biopsy). Both cross-sectional and long-term follow-up trials have consistently associated OLGA stages III-IV with a higher risk of GC. A recently-proposed modification of the OLGA staging system (OLGIM) basically incorporates the OLGA frame, but replaces the atrophy score with an assessment of intestinal metaplasia (IM) alone. A series of 4552 consecutive biopsy sets (2007-2009) was retrieved and reassessed according to both the OLGA and the OLGIM staging systems. A set of at least 5 biopsy samples was available for all the cases considered.

RESULTS: In 4460 of 4552 cases (98.0%), both the high-risk stages (III + IV) and the low-risk stages (0 +I + II) were assessed applying the OLGA and OLGIM criteria. Among the 243 OLGA high-risk stages, 14 (5.8%) were down-staged to a low risk using OLGIM. The 67 (1.5%) incidentally-found neoplastic lesions (intraepithelial or invasive) were consistently associated with high-risk stages, as assessed by both OLGA and OLGIM (P < 0.001 for both). Two of 34 intestinal-type GCs coexisting with a high-risk OLGA stage (stage III) were associated with a low-risk OLGIM stage (stage II).

CONCLUSION: Gastritis staging systems (both OLGA and OLGIM) convey prognostically important information on the gastritis-associated cancer risk. Because of its clinical impact, the stage of gastritis should be included as a conclusive message in the gastritis histology report. Since it focuses on IM alone, OLGIM staging is less sensitive than OLGA staging in the identification of patients at high risk of gastric cancer.

Helicobacter pylori outer membrane proteins on gastric mucosal interleukin 6 and 11 expression in Mongolian gerbils

BACKGROUND AND AIM

The levels of interleukin (IL)-6 and IL-11 in the gastric mucosa are related to mucosal inflammation; however, the chronological changes in cytokine expression during different phases of Helicobacter pylori infection and the effects of H. pylori virulence factors, particularly those of outer membrane proteins, remain obscure. The aim of this study was to clarify the chronological changes in cytokine levels in relation to several H. pylori outer membrane proteins.

METHODS

We studied Mongolian gerbils inoculated with wild-type H. pylori 7.13 for up to 48 weeks and then examined animals infected with oipA, babA, or alpAB isogenic mutants for 12 weeks. Mucosal IL-6 and IL-11 mRNA levels were measured using real-time reverse transcription-polymerase chain reactions.

RESULTS

High levels of gastric mucosal IL-6 and IL-11 mRNA in gerbils infected with wild-type H. pylori were observed during the chronic phase of infection, reaching maximums at 12 and 6 months, respectively. Infection with oipA and babA mutants resulted in significantly reduced cytokine levels and inflammatory cell infiltrations compared to gerbils infected with wild-type strains, and this persisted throughout the observation period. The alpAB mutants did not infect gerbils. Mucosal IL-6 and IL-11 levels were significantly associated with the grade of inflammatory cell infiltration.

CONCLUSIONS

OipA and BabA result in more severe H. pylori infection and increased IL-6 and IL-11 levels, which in turn may increase the risk of developing H. pylori-induced gastrointestinal diseases.

Helicobacter pylori therapy demystified

We discuss the role of comparators in Helicobacter pylori treatment trials and why anti-H. pylori therapeutic trials (an infectious disease) are fundamentally different from common gastrointestinal diseases (e.g., the absence of a placebo response, the expectation that cure rates in excess of 95%, and the ability to understand why treatment fails). No comparator is absolutely required other than to 100% success and comparison trials should be limited to comparisons between therapies that reliably achieve 90% or greater success (i.e., good therapies). Comparisons with known low success regimens (i.e., bad therapies) are unethical as is withholding information from the subject regarding current effectiveness of a regimen even if that information would reduce the likelihood that the subject would volunteer. We also discuss how it is possible to predict the outcome of a published but locally untried new regimen. The reason for different outcomes of typical gastrointestinal therapies is shrouded in mystery. In contrast, treatment success for H. pylori should be predictable and treatment failures explainable. For too long expectations and analyses of H. pylori therapy has been confused with what is appropriate for gastrointestinal disease such as constipation or irritable bowel syndrome rather than for infectious diseases such as pneumonia.

Paxillin is a novel cellular target for converging Helicobacter pylori-induced cellular signaling

Paxillin is involved in the regulation of Helicobacter pylori-mediated gastric epithelial cell motility. We investigated the signaling pathways regulating H. pylori-induced paxillin phosphorylation and the effect of the H. pylori virulence factors cag pathogenicity island (PAI) and outer inflammatory protein (OipA) on actin stress fiber formation, cell phenotype, and IL-8 production. Gastric cell infection with live H. pylori induced site-specific phosphorylation of paxillin tyrosine (Y) 31 and Y118 in a time- and concentration-dependent manner. Activated paxillin localized in the cytoplasm at the tips of H. pylori-induced actin stress fibers. Isogenic oipA mutants significantly reduced paxillin phosphorylation at Y31 and Y118 and reduced actin stress fiber formation. In contrast, cag PAI mutants only inhibited paxillin Y118 phosphorylation. Silencing of epidermal growth factor receptor (EGFR), focal adhesion kinase (FAK), or protein kinase B (Akt) expression by small-interfering RNAs or inhibiting kinase activity of EGFR, Src, or phosphatidylinositol 3-kinase (PI3K) markedly reduced H. pylori-induced paxillin phosphorylation and morphologic alterations. Reduced FAK expression or lack of Src kinase activity suppressed H. pylori-induced IL-8 production. Compared with infection with the wild type, infection with the cag PAI mutant and oipA mutant reduced IL-8 production by nearly 80 and 50%. OipA-induced IL-8 production was FAK- and Src-dependent, although a FAK/Src-independent pathway for IL-8 production also exists, and the cag PAI may be mainly involved in this pathway. We propose paxillin as a novel cellular target for converging H. pylori-induced EGFR, FAK/Src, and PI3K/Akt signaling to regulate cytoskeletal reorganization and IL-8 production in part, thus contributing to the H. pylori-induced diseases.

Twice-a-day bismuth-containing quadruple therapy for Helicobacter pylori eradication: a randomized trial of 10 and 14 days

BACKGROUND

Bismuth-containing quadruple therapy given twice a day for 14 days has been shown to be an excellent first-line H. pylori eradication therapy.

AIM

  To compare the efficacy and tolerability of twice-a-day bismuth-containing quadruple H. pylori eradication therapy for 10 versus 14 days in a noninferiority trial.

METHODS

Dyspeptic patients with H. pylori infection and naïve to H. pylori treatment were randomly assigned to: pantoprazole 20 mg, tetracycline 500 mg, metronidazole 500 mg, and bismuth subcitrate caplets 240 mg given b.i.d. (with the midday and evening meals) for 10 or 14 days. Eradication was defined by negative UBT and/or histology 4-6 weeks posttherapy. Efficacy and side effects were determined.

RESULTS

A total of 417 patients were randomized (153 men, 264 women; median age 52). Per protocol (PP) treatment success with 14 and 10 days was essentially identical [i.e., 96% (95% CI: 92-98) vs 95% (95% CI: 91-98) for 14 days versus 10 days, respectively. Results with intention-to-treat (ITT) analysis were also similar (92% (95% CI, 87-95) vs 92% (95% CI, 88-96)) for 14 and 10 days, respectively. Compliance was excellent in both groups. Side effects were generally mild and similar between groups. Fatigue, discomfort, and vomiting were more common in those in the 14-day group. The 10-day regimen costs € 17.65 (ie, approximately 25%) less than the 14-day regimen.

CONCLUSIONS

Bismuth-containing quadruple therapy remained highly effective (i.e., ≥95% PP and >90% ITT) despite reducing the duration from 14 to 10 days.

Serological responses to experimental Norwalk virus infection measured using a quantitative duplex time-resolved fluorescence immunoassay

A quantitative duplex time-resolved fluorescence assay, dissociation-enhanced lanthanide fluorescent immunoassay (DELFIA), was developed to measure Norwalk virus (NV)-specific IgA and IgG antibodies simultaneously. The duplex assay showed superior performance by detecting seroconversion following experimental NV infection at an earlier time point than a reference total immunoglobulin enzyme-linked immunosorbent assay (ELISA).

Incidence of esophageal carcinoma among Malays in North-Eastern Peninsular Malaysia: an area with an exceptionally low prevalence of Helicobacter pylori infection

BACKGROUND

Obesity, gastroesophageal reflux, and Barrett's esophagus have all been linked to esophageal adenocarcinoma. In addition, the decline in Helicobacter pylori (H. pylori) infection in affluent societies has also been suggested to be a major factor in the recent rise in the incidence of esophageal adenocarcinoma. If H. pylori infection has a protective role, populations with a naturally low prevalence of H. pylori infection such as the ethnic Malays of Northeastern Peninsular Malaysia should have high rates of esophageal adenocarcinoma.

AIM

To test this hypothesis, we investigated the incidence of esophageal carcinoma among the ethnic Malays of the state of Kelantan in Northeastern Peninsular Malaysia.

METHODS

The pathology services in the state of Kelantan are provided by two main hospitals. The histopathological records of both hospitals were systematically examined to retrieve all cases of esophageal carcinoma diagnosed between 2004 and 2008. Incidence rates were determined based on the most recent population census.

RESULTS

The age-standardized incidence rates (per 100,000 population) of esophageal adenocarcinoma among Malay men and women were 0.75 and 0.69, respectively. The corresponding rates for squamous cell carcinoma of the esophagus were 0.66 and 1.34, respectively.

CONCLUSIONS

The low rates of adenocarcinoma and squamous cell carcinoma of the esophagus in the study area, despite the fact that H. pylori infection is virtually absent, does not support the hypothesis that the absence of H. pylori infection is a pivotal factor in the pathogenesis of these cancers.

Diagnosis and management of iron deficiency anemia in the 21st century

Iron deficiency is the single most prevalent nutritional deficiency worldwide. It accounts for anemia in 5% of American women and 2% of American men. The goal of this review article is to assist practitioners in understanding the physiology of iron metabolism and to aid in accurately diagnosing iron deficiency anemia. The current first line of therapy for patients with iron deficiency anemia is oral iron supplementation. Oral supplementation is cheap, safe, and effective at correcting iron deficiency anemia; however, it is not tolerated by some patients and in a subset of patients it is insufficient. Patients in whom the gastrointestinal blood loss exceeds the intestinal ability to absorb iron (e.g. intestinal angiodysplasia) may develop iron deficiency anemia refractory to oral iron supplementation. This population of patients proves to be the most challenging to manage. Historically, these patients have required numerous and frequent blood transfusions and suffer end-organ damage resultant from their refractory anemia. Intravenous iron supplementation fell out of favor secondary to the presence of infrequent but serious side effects. Newer and safer intravenous iron preparations are now available and are likely currently underutilized. This article discusses the possible use of intravenous iron supplementation in the management of patients with severe iron deficiency anemia and those who have failed oral iron supplementation.

Modified sequential Helicobacter pylori therapy: proton pump inhibitor and amoxicillin for 14 days with clarithromycin and metronidazole added as a quadruple (hybrid) therapy for the final 7 days

BACKGROUND

Ten-day sequential therapy with a proton pump inhibitor (PPI) and amoxicillin followed by a PPI, clarithromycin, and an imidazole typically achieves Helicobacter pylori eradication rates of 90-94% (Grade B success).

AIMS

We tested whether prolonging treatment and continuing amoxicillin throughout the 14-day treatment period would produce a ≥ 95% result.

METHODS

This was a multicenter pilot study in which H. pylori-infected patients received a 14-day sequential-concomitant hybrid therapy (esomeprazole and amoxicillin for 7 days followed by esomeprazole, amoxicillin clarithromycin, and metronidazole for 7 days). H. pylori status was examined 8 weeks after therapy. Success was defined as achieving ≥ 95% eradication by per-protocol analysis.

RESULTS

One hundred and seventeen subjects received hybrid therapy. The eradication rate was 99.1% (95% confidence interval (CI), 97.3-100.0%) by per-protocol analysis and 97.4% by intention-to-treat analysis (95% CI, 94.5-100.0%). Adverse events were seen in 14.5%; drug compliance was 94.9%.

CONCLUSIONS

Fourteen-day hybrid sequential-concomitant therapy achieved > 95%H. pylori eradication (Grade A result). Further studies are needed 1, in regions with different patterns and frequencies of resistance to confirm these findings, and 2, to examine whether Grade A success is maintained with hybrid therapy shorter than 14 days.

Modified sequential Helicobacter pylori therapy: proton pump inhibitor and amoxicillin for 14 days with clarithromycin and metronidazole added as a quadruple (hybrid) therapy for the final 7 days

BACKGROUND

Ten-day sequential therapy with a proton pump inhibitor (PPI) and amoxicillin followed by a PPI, clarithromycin, and an imidazole typically achieves Helicobacter pylori eradication rates of 90-94% (Grade B success).

AIMS

We tested whether prolonging treatment and continuing amoxicillin throughout the 14-day treatment period would produce a ≥ 95% result.

METHODS

This was a multicenter pilot study in which H. pylori-infected patients received a 14-day sequential-concomitant hybrid therapy (esomeprazole and amoxicillin for 7 days followed by esomeprazole, amoxicillin clarithromycin, and metronidazole for 7 days). H. pylori status was examined 8 weeks after therapy. Success was defined as achieving ≥ 95% eradication by per-protocol analysis.

RESULTS

One hundred and seventeen subjects received hybrid therapy. The eradication rate was 99.1% (95% confidence interval (CI), 97.3-100.0%) by per-protocol analysis and 97.4% by intention-to-treat analysis (95% CI, 94.5-100.0%). Adverse events were seen in 14.5%; drug compliance was 94.9%.

CONCLUSIONS

Fourteen-day hybrid sequential-concomitant therapy achieved > 95%H. pylori eradication (Grade A result). Further studies are needed 1, in regions with different patterns and frequencies of resistance to confirm these findings, and 2, to examine whether Grade A success is maintained with hybrid therapy shorter than 14 days.

Is there a benefit to extending the duration of Helicobacter pylori sequential therapy to 14 days?

BACKGROUND AND AIMS

 Ten-day sequential therapy with a proton-pump inhibitor (PPI) and amoxicillin followed by a PPI, clarithromycin, and an imidazole typically achieves Helicobacter pylori (H. pylori) eradication rates between 90 and 94% (i.e., Grade B success). It has been suggested that prolonging the duration of therapy might improve the treatment success. We tested whether prolonging treatment duration to 14-days would improve the results to 95% or greater eradication.

METHODS

 This was a multi-center, single site, pilot study in which H. pylori-infected patients received a 14-day sequential therapy (esomeprazole and amoxicillin for 7 days followed by esomeprazole, clarithromycin, and metronidazole for 7 days). H. pylori status was assessed 8 weeks after therapy. Success was defined as achieving 95% or greater eradication by per-protocol (PP) analysis.

RESULTS

  One hundred and twenty-three subjects received the 14-day sequential therapy. The eradication rate was 93.9% (95% confidence interval [CI], 89.5-98.3%) by PP and 91.9% (95% CI, 87.1-96.7%) by intention-to-treat analysis. Adverse events were experienced by 21.1%; compliance of 90% or greater was 95.9%.

CONCLUSIONS

 Extending sequential therapy to 14 days did not result in improving the treatment outcome to 95% or greater.

Optimal therapy for Helicobacter pylori infections

Although Helicobacter pylori infection is both a common and a serious bacterial infection, antimicrobial therapies have rarely been optimized, are prescribed empirically, and provide inferior results compared with antimicrobial therapies for other common infectious diseases. The effectiveness of many of the frequently recommended H. pylori infection treatment regimens has been increasingly compromised by antimicrobial resistance. Regional data on the susceptibility of strains of H. pylori to available antimicrobials are sorely needed. Noninvasive molecular methods are possible to assess clarithromycin susceptibility in isolates obtained from stool specimens. As a general rule, clinicians should prescribe therapeutic regimens that have a ≥90% or, preferably, ≥95% eradication rate locally. If no available regimen can achieve a ≥90% eradication rate, clinicians should use the most effective regimen(s) available locally. Eradication of infection should always be confirmed after treatment in order to provide feedback regarding local effectiveness and an early warning of increasing resistance. In most regions of the world, four-drug treatment regimens, including a PPI plus three antimicrobials (clarithromycin, metronidazole/tinidazole and amoxicillin), or a PPI plus a bismuth plus tetracycline and metronidazole provide the best results. Standard triple therapy (a PPI, amoxicillin and clarithromycin) should now be avoided owing to increasing resistance to this treatment.

Effects of blood group antigen-binding adhesin expression during Helicobacter pylori infection of Mongolian gerbils

Helicobacter pylori outer membrane proteins, such as the blood group antigen-binding adhesin (BabA), are associated with severe pathological outcomes. However, the in vivo role of BabA during long-term infection is not clear. In this study, Mongolian gerbils were infected with H. pylori and necropsied continuously during 18 months. Bacterial clones were recovered and analyzed for BabA expression, Leb-binding activity, and adhesion to gastric mucosa. BabA expression was completely absent by 6 months post-infection. Loss of BabA expression was attributable to nucleotide changes within the babA gene that resulted in a truncated BabA. In response to the infection, changes in the epithelial glycosylation pattern were observed that were similar to responses observed in humans and monkeys. Furthermore, infections with BabA-expressing and BabA-nonexpressing H. pylori showed no differences in colonization, but infection with the BabA-expressing strain exhibited histological changes and increased inflammatory cell infiltration. This suggests that BabA expression contributes to severe mucosal injury.

Helicobacter pylori eradication therapy research: Ethical issues and description of results

As an infectious disease, the approach to anti-Helicobacter pylori therapy differs from other common gastrointestinal conditions because treatment success of more than 90% to 95% should be expected and the reasons for treatment failure can always be understood. Neither comparisons with another regimen nor randomization are required to identify a highly successful therapy. Treatment success should be judged first in relation to outcome (ie, ≥95% or grade A). Inclusion of a known inferior regimen in a clinical trial is generally unethical. If the use of a known inferior drug is required by a regulatory agency, subjects must be given full and accurate information regarding expectations with each regimen; there can be no deceptions. Comparative trials should be restricted to highly successful treatments (ie, comparisons of different doses, durations, compliance, cost, and so forth). Success should be judged as ordered categories such as <85%, 85%-89%, 90%-94%, or ≥95% and statistically equivalent regimens with the same grade success (ie, 90%-94% [Grade B]) are inferior to those higher category (ie, ≥95% [Grade A]) regimens. Only grade A or B regimens should be prescribed. Here we discuss anti-H pylori eradication studies from the perspective [corrected] of an infectious disease with the goal of providing recommendations regarding changes in approach and in reporting that should help resolve the ethical issues and make the results of clinical trials more useful to clinicians.

Strategy for eliminating gastric cancer in Japan

A study conducted by the Japan Gast Study Group showed that eradication of Helicobacter pylori reduced the risk of gastric cancer by about one-third. However, it did not completely prevent the onset of latent gastric cancer among those at high risk (i.e., with atrophic gastritis). To prevent deaths from gastric cancer, it is necessary to eradicate H. pylori infection. We propose a program of risk stratification based on the presence of H. pylori infection with or without atrophic gastritis followed by targeted interventions. Those at no risk for gastric cancer (no H. pylori, no atrophic gastritis) need no therapy or follow-up. Those at low risk (H. pylori infected, nonatrophic gastritis) need only H. pylori eradication therapy. The smaller groups at high or very high risk need eradication and cancer surveillance. We estimated the costs and the benefits of this strategy. Gastric cancer screening by simultaneous measurement of serum pepsinogen and H. pylori antibody combined with eradication of H. pylori in all individuals at risk would initially increase national healthcare expenditure, but this would be offset by markedly reducing the cost of treating gastric cancer. The proposed strategy should prevent about 150,000 deaths from gastric cancer during the 5 years after its adoption. If the loss caused by these deaths is also taken into account, the economic effect of this strategy becomes enormous. It would probably reduce the incidence of gastric cancer by more than 80-90% within 10 years. The Japanese government should take the initiative to implement this strategy as soon as possible.

Helicobacter pylori infection among Aborigines (the Orang Asli) in the northeastern region of Peninsular Malaysia

Whether the exceptionally low prevalence of Helicobacter pylori (HP) infection reported among Malays is also present among aborigines (the Orang Asli) living in northeastern Peninsular Malaysia is unknown. We studied asymptomatic Orang Asli from settlements situated 210 km from the city of Kota Bharu. The HP infection status was confirmed by a validated serology test. Nineteen percent of 480 Orang Asli tested positive for HP infection. The prevalence was 40.6% in the birth cohort of the 1940s and declined steadily in later cohorts to under 10% among 12-30 year olds. This may be related to the phases of relocation from the jungles into resettlement camps and ultimately into designated villages near rivers. The low prevalence pattern after the 1970s was probably partly a result of improvement in sanitation and hygiene practice in these villages but other unidentified factors may also be operating.

Serological correlate of protection against norovirus-induced gastroenteritis

BACKGROUND

Norovirus infection is the leading cause of acute nonbacterial gastroenteritis. Histoblood group antigens (HBGAs) are host susceptibility determinants for Norwalk virus (NV) infection. We hypothesized that antibodies that block NV-HBGA binding are associated with protection from clinical illness following NV exposure.

METHODS

We developed an HBGA blocking assay to examine the ability of human serum to block the interaction of NV viruslike particles with H type 1 and H type 3 glycans. Serum samples from persons who were experimentally challenged with NV were evaluated.

RESULTS

There was a high correlation between the H type 1 and H type 3 synthetic glycan assays (r = 0.977; P < .001); the H type 1 assay had higher quantitative sensitivity (P < .001). Among 18 infected secretor-positive individuals, blocking titers peaked by day 28 after challenge and were higher for individuals who did not develop gastroenteritis than for those who developed gastroenteritis on days 0, 14, 28, and 180 (P < .05 for each). In addition, 6 of 6 subjects without gastroenteritis had measurable prechallenge blocking titers (>25), compared with 2 of 12 subjects with gastroenteritis (P = .002).

CONCLUSIONS

Blocking antibodies correlate with protection against clinical NV gastroenteritis. This knowledge will help guide the evaluation of new vaccine strategies and the elucidation of the nature of immunity to the virus. Trial registration. ClinicalTrials.gov identifier: NCT00138476.

Helicobacter pylori infection in India from a western perspective

Helicobacter pylori is a common bacterial infectious disease whose manifestations predominately affect the gastrointestinal tract. India is the prototypical developing country as far as H. pylori infection is concerned and more than 20 million Indians are estimated to suffer from peptic ulcer disease. Considering the high level of Medicine and of the pharmaceutical industry, one would expect that India would be the source of much needed information regarding new therapies and approaches that remain effective in the presence of antimicrobial resistance, new methods to reliably prevent reinfection, and the development of therapeutic and preventive vaccines. Here, we discuss H. pylori as an Indian problem with an emphasis on H. pylori infection as a serious transmissible infectious disease. We discuss the pros and cons of eradication of H. pylori from the entire population and come down on the side of eradication. The available data from India regarding antimicrobial use and resistance as well as the effectiveness of various treatments is discussed. Rigorous ongoing studies to provide current regional antibiotic resistance patterns coupled with data concerning the success rate with different treatment regimens are needed to guide therapy. A systematic approach to identify reliably effective (e.g., 90% or greater treatment success) cost-effective regimens is suggested as well as details of regimens likely to be effective in India. H. pylori is just one of the health care problems faced in India, but one where all the resources are on hand to understand and solve it.

Pharmacologic aspects of eradication therapy for Helicobacter pylori Infection

The commonly used regimens for the eradication of Helicobacter pylori infection consist of administration of proton pump inhibitors (PPIs) and 1 to 3 antimicrobial agents, such as amoxicillin, clarithromycin, metronidazole, fluoroquinolone, or tetracycline. Each agent has its own pharmacologic characteristics. PPIs are metabolized by cytochrome P450 2C19 (CYP2C19), which is polymorphic. CYP2C19 genotypic differences in the pharmacokinetics and pharmacodynamics of PPIs influence the eradication rates of H pylori infection by PPI-containing regimens. Amoxicillin is a time-dependent antibiotic, whereas clarithromycin, metronidazole, tetracycline, and fluoroquinolone are not. The plasma half-life of antimicrobial agents also differs among these antibiotics. To achieve consistently high eradication rates, the eradication regimens must be designed based on a good understanding of the resistance patterns of the bacteria and the pharmacologic characteristics of the agents used for H pylori eradication therapy.

Helicobacter pylori treatment in the era of increasing antibiotic resistance

With few exceptions, the most commonly recommended triple Helicobacter pylori regimen (proton pump inhibitor (PPI), amoxicillin and clarithromycin) now provides unacceptably low treatment success. A review of worldwide results suggests that successful eradication using a triple regimen is not consistently observed in any population. Clinicians should use 'only use what works locally' and ignore consensus statements and society guidelines if they are not consistent with local results. Clinical trials should be result based, with the goal of identifying regimens with >90-95% success. New treatments should be only be compared with the currently locally effective treatment (>90%) or a historical untreated control (which has been shown to reliably yield 0% eradication); trials using placebos or treatments known to be inferior are with rare exceptions unethical. If a highly effective regimen is not available locally, we recommend trying a 14 day concomitant quadruple treatment regimen containing a PPI, amoxicillin, clarithromycin and a nitroimidazole; 10 day sequential treatment (PPI plus amoxicillin for 5 days followed by a PPI, clarithromycin and a nitroimidazole for 5 days); or 14 day bismuth-containing quadruple treatments. Treatments needing further evaluation include those containing furazolidone or nitazoxanide, hybrids of sequential-concomitant therapies and amoxicillin-PPI dual therapy with PPI doses such that they maintain intragastric pH >6.

Addition of gentamicin to endoscopic retrograde cholangiopancreatography (ERCP) contrast medium towards reducing the frequency of septic complications of ERCP

OBJECTIVE

Bacteremia and sepsis are serious complications of endoscopic retrograde cholangiopancreatography (ERCP) and occur in between 0.5 and 3% of cases. Patients with obstructed bile ducts are at highest risk of developing septic complications. The purpose of this investigation was to determine whether the addition of gentamicin to the ERCP contrast medium prevents or reduces the growth of Pseudomonas aeruginosa in vitro.

METHODS

Artificial bile ducts were fashioned out of dialysis tubing and suspended in flasks containing brain heart infusion (BHI) broth. The tubing contained BHI broth alone, with or without contrast medium or with contrast medium plus gentamicin. The artificial ducts were inoculated with gentamicin-sensitive or gentamicin-resistant P. aeruginosa and quantitative cultures were performed.

RESULTS

The contrast medium alone was bacteriostatic to both sensitive and resistant P. aeruginosa isolates. The addition of gentamicin to the contrast medium eliminated the sensitive strain after 2 h and resulted in a reduction in the number of gentamicin-resistant P. aeruginosa after 4 h. Incubation of the resistant isolate in the presence of contrast and gentamicin for an additional 4 h led to a further reduction in viable bacteria but did not completely eliminate the organisms.

CONCLUSION

These results support the use of gentamicin in the contrast medium injected into the biliary system as an ancillary method to prevent post-ERCP sepsis.