Fully covered self-expanding metal stents for benign colonic strictures.

BACKGROUND AND STUDY AIMS: Uncovered self-expanding metal stents offer effective relief for colonic obstruction. The aim of this study was to determine the effectiveness of fully covered self-expanding metal stents (FCSEMSs) in the treatment of benign colonic strictures. PATIENTS AND METHODS: All patients presenting with a symptomatic benign colonic stricture (occlusion or subocclusion) during a 6-year study period were treated with FCSEMSs. The stents were placed and removed 4 - 6 weeks later at one of 10 endoscopy centers. The efficacy of the stent (clinical and radiological signs of colonic decompression within 48 hours), technical success, stent retrieval, safety, and recurrence of symptoms were evaluated during follow-up. Univariate and multivariate analyses were performed to identify variables associated with clinical success, stent migration, and symptom recurrence. RESULTS: The study included 43 patients (24 men, 19 women; mean age 67.6 ± 10.4) with occlusive (n = 18) or subocclusive symptoms (n = 25) due to anastomotic (n = 40), post-ischemic (n = 2), or post-radiation (n = 1) strictures. Insertion was successful in all patients. Clinical success was obtained in 35 patients (81 %). Migration was observed in 27 patients (63 %). The median duration of stenting was 21 days (95 %CI 17.8 - 35.4 days). Multivariate analysis showed that stents more than 20 mm wide migrated significantly less often. Recurrence of obstructive symptoms was observed in 23 patients (53 %), irrespective of migration. No predictive factors for recurrence or clinical efficacy were found. CONCLUSIONS: FCSEMSs for treatment of symptomatic benign colonic strictures are safe and effective, despite a high rate of spontaneous migration.

Accuracy of computed tomographic colonography in a nationwide multicentre trial, and its relation to radiologist expertise.

OBJECTIVE: Reports on the accuracy of computed tomographic colonography (CTC) mainly involve series from expert institutions. The aims of this study were to assess CTC accuracy in a nationwide population and to relate it to radiologist performance in their initial training. DESIGN: Nationwide multicentre trial. SETTING: Twenty-eight radiologists, working in 26 mostly academic clinical units, were involved in the study after having attended a formal specialised 2-day training session on CTC. They worked through a training set of 52 cases with automatic feedback after an attempt at each case. PATIENTS: The study enrolled 845 patients with average and high risk of colorectal cancer, 737 of whom had both complete CTC and videocolonoscopy data, which constituted the dataset. INTERVENTIONS: Patients underwent same-day CTC followed by videocolonoscopy with segmental unblinding of CTC results. MAIN OUTCOME MEASURES: Sensitivity, specificity and positive and negative predictive values for detection of polyps ≥ 6 mm in per-patient and per-lesion analyses of CTC without computer-aided detection. RESULTS: Sensitivity, specificity and positive and negative predictive values for patients with polyps ≥ 6 mm were 69% (95% CI 61% to 77%), 91% (95% CI 89% to 94%), 67% (95% CI 59% to 74%) and 92% (95% CI 90% to 94%), respectively. Univariate analysis showed that the detection rate for polyps ≥ 6 mm was linked to neither radiologist case volume nor number of polyps, but was related to sensitivity achieved in the training set. Pooled sensitivity was 72% (95% CI 63% to 80%) versus 51% (95% CI 40% to 60%) for radiologists achieving above and below median sensitivity in the training set (61%), respectively. Multivariate analysis showed that sensitivity for polyps ≥ 6 mm in the training set was the only remaining significant predictive factor for subsequent performance. CONCLUSIONS: Radiologist sensitivity CTC for detection of polyps ≥ 6 mm in training was the sole independent predictor for subsequent sensitivity in detection of such polyps.

The efficacy and safety of duodenal stenting: a prospective multicenter study.

BACKGROUND AND STUDY AIMS: Duodenal stenting has become a popular treatment in cases of malignant stenosis. However, a prospective evaluation of the efficacy and morbidity of this procedure has not been performed. A prospective multicenter study of duodenal stenting was conducted by the Société Française d'Endoscopie Digestive (SFED). PATIENTS AND METHODS: A total of 51 patients were selected (mean age 72), the majority (69%) having pancreatic adenocarcinoma. Palliative treatment was chosen because of irresectability (61.2%), inoperability (18.4%), or both (20.4 %). Enteral Wallstent prostheses were used, and the patients were followed up on day 3, after 1 month, and then every month, with weight measurement, and symptomatic and laboratory evaluation. RESULTS: One prosthesis was sufficient in 46 patients. Stent positioning and deployment were correct in 50/51 patients (98%). Twenty patients also underwent biliary stenting in addition to the duodenal stenting. On day 3, 43 patients (84%) were able to tolerate soft solids or a full diet. Six complications were attributed to stenting: three intestinal hemorrhages, two cases of peritonitis due to bowel perforation, and one case of septicemia, and these led to five deaths (mortality 9.8%). Stent dysfunction was observed in 12 cases (23.5%) after a mean delay of 75 days, comprising 11-malignant obstructions and one migration: a new stent was inserted inside the first one and was effective in eight cases; and no treatment was given in the other four patients because of their clinical state. The median survival was 71.5 days. CONCLUSIONS: Palliative endoscopic treatment of malignant duodenal stenosis using metallic prostheses is highly feasible, even with associated biliary stenting. Symptomatic improvement is fast. However, the mortality and the obstruction rate are high, suggesting that a prospective trial comparing this treatment with surgery is still required.

Similar performance but higher cholecystitis rate with covered biliary stents: results from a prospective multicenter evaluation.

BACKGROUND AND STUDY AIMS: Endoscopic biliary stenting is now a well-established treatment method in patients with unresectable malignant biliary obstruction. Despite advances with metal stents, the problem of stent occlusion has not yet been resolved. Covered metal stents could reduce the occlusion rate by preventing tumor ingrowth, but have not been well evaluated. A prospective multicenter study was therefore conducted to evaluate the efficacy and disadvantages of covered Wallstents. PATIENTS AND METHODS: Covered Wallstents were implanted endoscopically in 62 patients with inoperable distal malignant biliary obstruction. Complications, stent patency, and patient survival were analyzed. RESULTS: Stent insertion was achieved in 61 of the 62 patients (98.4 %). Procedure-related complications were observed in four patients, consisting of minor pancreatitis (n = 2) and abdominal pain due to stent expansion (n = 2). There was no procedure-related mortality. Seven patients died too early for proper assessment, so that a total of 54 patients were ultimately evaluated. Stent dysfunction occurred in 17 of the 54 patients (31.5 %). The reasons for dysfunction were proximal tumor overgrowth (n = 5), migration (n = 3), lithiasis or food impaction (n = 3), cholangitis without the need for a repeat biliary intervention (n = 5), and unknown (n = 1). The median period of stent patency was 142 days. No tumor ingrowth was observed. Acute cholecystitis was diagnosed in five patients (10 %) and was responsible for one death. Three stents were successfully removed. CONCLUSIONS: Covered biliary metal stents are effective for the drainage of distal malignant biliary obstruction, with a dysfunction rate apparently similar to that of uncovered stents. However, the risk of acute cholecystitis appears to be a major concern with this type of stent in patients with gallbladder in situ. Further comparative studies are needed.

cagA Status and eradication treatment outcome of anti-Helicobacter pylori triple therapies in patients with nonulcer dyspepsia.

The differences in eradication rates reported in clinical trials aiming to cure Helicobacter pylori infection cannot be entirely explained by the type of regimen, bacterial resistance, or lack of compliance. Using data from a clinical trial, a logistic regression model was constructed to determine whether cagA status, assessed by PCR, affects the outcome of eradication. Resistance to clarithromycin (10% of the strains) predicted failure perfectly. In the model (n = 156), a cagA-lacking strain (odds ratio [OR] = 2.2; 95% confidence interval [CI], (1.1 to 4.7), tobacco smoking OR = 3.1; 95% CI, 1.3 to 7.0), and a double dose of proton pump inhibitor in the treatment regimen (OR = 0.3; 95% CI, 0.2 to 0.7) were associated with the treatment outcome. The exact role of cagA in the outcome of H. pylori eradication therapy has not been explored. However, the type of histological lesions which it causes in the gastric mucosa may be implicated. Regardless of the mechanism involved, cagA status is a good predictive marker of eradication outcome.

Diagnosis of Helicobacter pylori infection: noninvasive methods compared to invasive methods and evaluation of two new tests.

OBJECTIVES: Current guidelines recommending Helicobacter pylori eradication treatment without performing endoscopy in certain patients highlight the importance of noninvasive tests. Our aim was to determine the accuracy of two new tests: the antigen stool test and Helicoblot 2.1 (an immunoblot used on serum) as well as the 13C urea breath test and ELISA serology in comparison to invasive tests for the pretreatment diagnosis of H. pylori infection. METHODS: Helicobacter pylori infection was diagnosed prospectively in 104 untreated patients using eight different tests. Invasive tests included culture, urease test (CLOtest), histology, and PCR; noninvasive tests included the 13C urea breath test, IgG serology (Pyloriset EIA-G), immunoblot (Helicoblot 2.1), and antigen stool detection (Premier Platinum HpSA). A predefined gold standard based on biopsy tests was used to define H. pylori status, as well as an empirical approach. RESULTS: There was no statistically significant difference between the different tests. The sensitivity of the noninvasive tests ranged between 88.9% and 95.6% (stool test: 88.9%, 95% CI: 82.7-95.1, and Helicoblot 2.1: 95.6%, 95% CI: 91.5-99.6) and the specificity ranged between 92.6 and 98.1% (stool test: 94.4%, 95% CI: 84.6-98.8, and Helicoblot 2.1: 92.6%, 95% CI: 91.5-96.2) when a predefined gold standard was used. CONCLUSIONS: Most tests had sensitivities, specificities, and predictive values >90%. The noninvasive tests are accurate for the diagnosis of H. pylori infection. Helicoblot 2.1 performed as well as the best ELISA kit. The HpSA is a promising direct noninvasive test that can be applied easily to evaluate H. pylori status.

Long-term effects of Helicobacter pylori eradication on gastric antral mucosa in duodenal ulcer patients.

OBJECTIVES: The aim of this study was to assess the consequences of prolonged Helicobacter pylori eradication on gastric antral mucosa in duodenal ulcer patients. PATIENTS AND METHODS: Forty-three duodenal ulcer patients with confirmed H. pylori eradication after one year of follow-up were included in this retrospective study. Before H. pylori eradication and during the follow-up, four antral prepyloric biopsy samples were taken for histopathological examination and culture. Histopathological lesions were graded semi-quantitatively according to the updated Sydney System for activity, chronic inflammation, glandular atrophy and intestinal metaplasia (IM), as well as presence of lymphoid follicles. RESULTS: After a mean follow-up of 43 +/- 23 months, H. pylori eradication statistically improved all gastritis scores, including the atrophy score and the lymphoid follicle score but excluding the IM score. H. pylori eradication resulted in normalization of gastric mucosa in 51.2% of patients and a significantly lower proportion of patients with non-atrophic gastritis and atrophic gastritis without IM. Atrophy totally disappeared in 16/29 patients (55.2%) in whom IM was absent. No predictive factor for regression of atrophy or normalization of gastric mucosa was identified. CONCLUSION: In duodenal ulcer patients, prolonged absence (more than one year) of H. pylori can lead to normalization of the antral mucosa and the disappearance of mucosa-associated lymphoid tissue, as well as the regression of antral atrophy. Long-term studies involving selected patients with atrophy and IM which persist after H. pylori eradication are needed to determine the potential benefits of treating H. pylori gastritis with regard to gastric cancer prevention.

Laser assisted ratio analyser 13C-urea breath testing, for the detection of H. pylori: A prospective diagnostic European multicentre study.

BACKGROUND: Novel technology based on laser optogalvanic spectroscopy called the LARA (Laser Assisted Ratio Analyser) system was developed to measure 12C/13C ratios in breath samples using stable 13C isotopes, to detect Helicobacter pylori infection. AIM: To determine the sensitivity and specificity of the 13C-LARA-urea breath test in the detection of H. pylori infection in a prospective European multicentre trial; FDA-and EMEA-approved. METHODS: Consecutive dyspeptic patients underwent diagnostic gastroscopy with biopsies for culture and histopathology, to detect H. pylori infection (gold standard). Subsequently, the LARA-urea breath test was performed using either a system without a cold trap (part I) or a system with a cold trap (part II). In both instances baseline, 30-min and 60-min breath samples were collected. The optimum cut-off level for 12C/13C ratios was determined by Receiver Operator Characteristics analysis. RESULTS: In part I, 544 out of 604 patients were evaluable (low CO2: 47; withdrawn: 13). 284 out of 544 patients (52%) were H. pylori-positive according to the gold standard. The sensitivity of the LARA-urea breath test was 95% and the specificity 94%. In part II, 257 out of 272 were evaluable (low CO2: 14; withdrawn: 1). Sensitivity and specificity were 93% and 96%, respectively. CONCLUSION: The LARA-technology represents an accurate and non-invasive testing system for the detection of H. pylori infection. Its major advantages are the use of stable 13C isotope, the high throughput of samples and the easy means of collecting, storing and transporting the samples, thus making the system convenient to both patient and clinician.

[Three deceptive cases of intrahepatic metastases of colorectal origin with endobiliary growth, simulating cholangiocarcinoma. Importance of immunostaining of cytokeratin 7 and 20]. / Trois cas trompeurs de métastases intrahépatiques d'origine colorectale à développement endobiliaire, simulant un cholangiocarcinome. Intérêt de l'immunomarquage des cytokératines 7 et 20.

Malignant tumors of the liver with intrabiliary growth are rare, except for some cholangiocarcinomas. Metastases with intrabiliary growth, whatever their origin, are rare. Moreover, colorectal metastasis can be particularly difficult to distinguish morphologically from some cholangiocarcinomas. We report 3 cases of late colorectal metastasis with intrabiliary growth, presenting as cholangiocarcinomas of the large ducts. Immunostaining with cytokeratins 7 and 20 attested the diagnostic and pointed out the spreading pattern of colorectal metastasis within biliary ducts. This study illustrates the capacity, probably underestimated, for colorectal metastasis to develop in the lumen of bile ducts and emphasizes the relevance of cytokeratin 7 and 20 immunostainings in such cases.

Direct detection of Helicobacter pylori resistance to macrolides by a polymerase chain reaction/DNA enzyme immunoassay in gastric biopsy specimens.

BACKGROUND: The increasing use of macrolides especially in the treatment of Helicobacter pylori infection has led to an increase in resistant strains. The resistance of H pylori to macrolides, especially clarithromycin, is one of the major causes of eradication failure. In H pylori, clarithromycin resistance is due to point mutations localised in domain V of 23S rRNA. AIM: To develop a molecular technique based on amplification of a relevant fragment of the 23S rRNA and colorimetric hybridisation in liquid phase to detect directly in biopsy specimens the type of mutation associated with resistance of H pylori to clarithromycin. METHODS: Gastric biopsy samples from 61 patients were submitted to this test. The results were compared with standard methods (determination of minimal inhibition concentration, polymerase chain reaction/restriction fragment length polymorphism, and/or DNA sequencing) in order to evaluate the test and to define the cut off values, specificity, and sensitivity. RESULTS: The 14 biopsy samples in which H pylori was not detected did not give a positive result in any assay, and the 14 samples harbouring strains susceptible to clarithromycin gave a positive result with the wild type probe as expected. The 33 biopsy specimens containing resistant strains always gave a positive signal with one of the probes detecting resistant organisms, but in eight cases they also reacted with the wild type probe, indicating that a mixture of resistant and susceptible organisms was present. CONCLUSION: The importance of this new assay is that it allows the detection of multiple genotypes corresponding to either heterogeneous genotypes or mixed infections. Moreover, it allows in a single step not only the detection of H pylori but also the determination of its susceptibility to clarithromycin directly in biopsy specimens without the need for culture.

[Helicobacter infections of man and of domestic carnivores: comparative data]. / Hélicobactérioses de l'homme et des carnivores domestiques: quelques données comparatives.

The role of Helicobacter pylori in generating of the chronic gastritis and in the maintaining of the gastroduodenal ulcerous disease, has been a major medical discovery of these past years in human gastroenterology. More recently in Man, studies have showed that the gastric tumours (adenocarcinoma, lymphoma) are epidemiologically associated with the H. pylori infection. Although the H. pylori infection is the one of the most frequent in the word, the epidemiologic and ecologic aspects of this infections are still not very well known. Thanks to phylogenic studies using the new molecular biology techniques and to fundamental experimental studies, we know more about helicobacteria in domestic carnivores as well as their morphologic characteristic, their taxonomia and more importantly details concerning their ecological niche. Few clinical studies have been made to this day, but the ones that have been undertaken are interesting in confirming the extensive prevalence of Helicobacter infections in domestic carnivores and in underlining their role in the genesis of the inflammatory gastropathies observed in these species. Recent observations have demonstrated the ubiquitous character of these helicobacteria by showing their presence in the stomach of man, dogs and cats. This ubiquitous character has led some scientists to consider the potential zoonotic risk of the human infection by Helicobacter heilmannii, felis or pylori. Finally, the Helicobacter infection of animals seems to be an interesting model not only in the study of the affections caused by these bacteria, but also in the elaboration of a future vaccine against the H. pylori infection in man.

Quantitative polymerase chain reaction for the detection of Helicobacter pylori in gastric biopsy specimens.

A variety of methods, including the polymerase chain reaction (PCR), are available for the detection of Helicobacter pylori in clinical samples, but none of them can adequately quantify the organism. In the present study, the competitive PCR, a rapid and simple method for quantification of Helicobacter pylori DNA in gastric biopsies, was used to measure the amount of DNA present in Helicobacter pylori-positive biopsies. This method is based on coamplification of an internal standard and a target DNA sequence with one set of primers. The internal standard was prepared using a nonhomologous fragment of DNA ligated to specific primers used to amplify the target DNA. This competitive DNA fragment of a desired size and containing primer templates is called a PCR MIMIC. To perform a quantitative PCR, PCR amplification reactions were spiked with known quantities of PCR MIMICs containing unknown amounts of DNA from Helicobacter pylori-positive biopsies. The amount of target DNA was determined by visual comparison of the PCR products after establishment of the correlation between the internal control concentration and the DNA concentration in a competitive amplification reaction. The results were confirmed by a radioactive method. Quantitative PCR can be a reliable method for determining the extent of Helicobacter pylori infection.

Mesalamine in Crohn's disease with steroid-induced remission: effect on steroid withdrawal and remission maintenance, Groupe d'Etudes Thérapeutiques des Affections Inflammatoires Digestives.

BACKGROUND & AIMS: Steroid dependence and early relapse are frequent after a prednisolone-induces remission in Crohn's disease. The aim of this trial was to test whether mesalamine started at the onset of steroid tapering increases the rate of weaning from prednisolone and reduces the relapse rate after prednisolone cessation. METHODS: One hundred fifty patients with active Crohn's disease were administered oral prednisolone (1 mg.kg(-1). day(-1)) x 3-7 weeks; 129 patients went into clinical remission and were randomized to Pentasa (4 g . day(-1)) or placebo, administered until weaning and for 1 year thereafter. RESULTS: Groups were similar for clinical and biological items collected initially. Weaning failure rate was 30% and 12% in the placebo and mesalamine arms, respectively. At the end of the trial, 9 of 36 patients administered placebo and 14 of 48 administered mesalamine were in remission. Both groups had similar time to relapse curves in the postweaning year; after adjusting for risk factors (high Crohn's Disease Activity Index, white blood cell count of >9 x 10(9) /l-1 at weaning, and use of a medical treatment in the month before inclusion), Pentasa was found to be superior to placebo. CONCLUSIONS: After a prednisolone-induces remission in Crohn's disease, mesalamine facilitates steroid withdrawal and, during the postweaning year, may reduce the relapse rate in certain patient subgroups.

[Follicular gastritis in adults. Relations with Helicobacter pylori, histological and endoscopic aspects]. / Les gastrites folliculaires de l'adulte. Relations avec Helicobacter pylori, aspects histologiques et endoscopiques.

Follicular gastritis (FG) is characterized by lymphoid follicle hyperplasia in the gastric mucosa. The aim of this prospective study was to determine the prevalence of FG in adults, their relation to Helicobacter pylori infection, and their histological and endoscopic features. Of 445 patients (379 men, 66 women), 36.4 years old (range: 18-86), FG was detected in 63 patients (14.2%). This was highly significantly associated with H. pylori infection: 49/138 infected patients (35.5%) versus 14/307 non infected patients (4.6%) (P < 0.001). None of the histological features of the antral mucosa were correlated with FG. The prevalence of FG in patients less than 20 years old (in 45.4%) and between 20 and 40 years (in 41.3%) was higher than in patients aged from 40 to 60 years (in 33%) and older than 60 years (in 23%) (no significant difference). No one endoscopic feature of the gastric mucosa was predictive of the presence of FG. We conclude that FG is highly correlated with H. pylori infection and represents a local immune response to bacterial antigens. Their occurrence is probably multifactorial and related to age, duration of infection, bacterial strains, host immune status.

Propranolol reduces the rebleeding rate during endoscopic sclerotherapy before variceal obliteration.

In patients treated with sclerotherapy, most rebleeding episodes are observed before variceal obliteration. This prospective randomized study aimed to assess if propranolol together with sclerotherapy could reduce the rebleeding rate before variceal obliteration. Seventy-five patients (59 male, 16 female; mean age, 54 +/- 15 years) with cirrhosis (from alcohol abuse in 91%) admitted with upper gastrointestinal bleeding, which was endoscopically proven to originate from ruptured esophageal varices, were included. After initial control of bleeding, the patients were randomized into the following two groups: group 1 treated with sclerotherapy alone (36 patients) and group 2 treated with sclerotherapy plus propranolol (39 patients). They were followed up to variceal obliteration. In group 2, 7 patients rebled as compared with 14 patients treated with sclerotherapy alone (P less than 0.005). When considering only rebleedings from esophageal varices, 4 patients rebled in group 2 vs. 10 in group 1 (P less than 0.10). The total number of rebleeding episodes was lower in group 2 than in group 1 whether considering all causes (8 vs. 17; P less than 0.07) or variceal rebleedings alone (4 vs. 13; P less than 0.01). Mean total blood requirement per patient was lower in group 2 than in group 1 (1.4 +/- 3.4 vs. 2.79 +/- 6.4 units of blood, respectively; P less than 0.01). Mortality was similar in both groups of patients (14% vs. 13% in groups 1 and 2, respectively, NS). It is concluded that patients treated with sclerotherapy should be given propranolol before variceal obliteration.

Bactericidal effect of amoxicillin on Helicobacter pylori in an in vitro model using epithelial cells.

The treatment of Helicobacter pylori with antimicrobial agents has largely been ineffective, and susceptibility results are in disagreement with those obtained by standard in vitro testing. The bactericidal effect of amoxicillin was tested in an in vitro model by using sessile bacteria attached to HEp-2 cells; this bactericidal effect was compared with that against planktonic bacteria. Viable cell counts were performed by standard procedures after 1, 6, and 24 h of contact with the antibiotic at different concentrations. A bactericidal effect (99.9% killing) was observed against sessile bacteria after 24 h with concentrations of only 10, 1, and 0.1 mg/liter, while against planktonic bacteria it was also noted at concentrations of 0.01 and 0.001 mg/liter, and the effect was observed after 6 h with the three highest concentrations. When the results for five strains were studied by analysis of variance at 6 and 24 h, the main variable was the antibiotic concentration, followed by the culture conditions, e.g., planktonic or sessile bacteria, the strain tested, and the time of contact. A decreased pH of 5.4 did not affect the action of amoxicillin. The bactericidal effect of the combination of amoxicillin and metronidazole was additive against sessile H. pylori.

Liver sinusoids and sinusoidal cells in patients with agnogenic myeloid metaplasia.

The origin of sinusoidal portal hypertension often remains unknown in patients with agnogenic myeloid metaplasia. Four consecutive patients with agnogenic myeloid metaplasia had liver biopsies examined under light and electron microscopy. Two of the four had obvious clinical portal hypertension; of these two, only one had portal vein thrombosis. All four cases showed sinusoidal infiltration by myeloid cells (from very mild to obvious) and an increased perisinusoidal collagen network. Under electron microscopy we observed (a) the collagenization of the Disse space, (b) myeloid cells in the lumen and the Disse space, (c) the transformation of perisinusoidal cells into transitional cells, and (d) fragments of basement membrane-like material. It is possible that all these abnormalities, and not only sinusoidal infiltration, contribute to increase vascular resistance, even when there is no clinical evidence of portal hypertension unrelated to vascular thrombosis.