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M Stolte

Publications and source records attributed to M Stolte.

At least 199 records · Page 11Linked to original sources
PubMed1999

A multicentre evaluation of the laser assisted ratio analyser (LARA): a novel device for measurement of 13CO2 in the 13C-urea breath test for the detection of Helicobacter pylori infection.

BACKGROUND: The laser assisted ratio analyser (LARA) was developed as a novel device to measure 13CO2 in the urea breath test for the detection of H. pylori infection. The analyser was tested in a prospective multicentre study in 444 patients in North America (Phase 1) followed by second study involving 160 patients (Phase 2). METHODS: Patients undergoing endoscopy for clinical indications had antral and gastric biopsies taken for histological examination, culture and CLO test. One hour after endoscopy, a baseline breath sample was obtained, 100 mg of 13C-urea were ingested and breath samples were obtained at 30 and 60 min post ingestion. Data obtained with the LARA were compared with the results of culture, rapid urease testing and central pathology in two different combinations {reference standards}. The study was conducted in two phases: in Phase 2, a modification was made to the LARA that improved the removal of water vapour from the breath sample. RESULTS: In Phase I, data from 331 patients were analysed using a cut off of (delta) 7.8 +/- 0.8, the sensitivity of the method was 91.7% and the specificity was 86.5%, using the reference standard of 2 of 3 tests (CLO, culture or histology) being positive. Positive and negative predictive values were, respectively, 85.2% and 92.5%. In Phase 2 of the study, 160 patients were enrolled and 141 patients were analysed using the same standards. We used the same reference standards but with a cut off of (delta) 6.1 +/- 0.6. The sensitivity and specificity increased to 96.8% and 98.6%, respectively. Positive and negative predictive values were, respectively, 98.4% and 97.3%. The detection rates for H. pylori were similar in patients with peptic ulcer or H. pylori associated gastritis. CONCLUSIONS: The LARA provides an accurate non-invasive means of detecting 13CO2 in the 13C-urea breath test for H. pylori in a multicentre clinical environment that compares well with invasive 'gold standard' methods.

Adolescent↗
PubMed1999

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.

Adolescent↗
PubMed1999

Observer agreement on the grading of gastric atrophy.

AIMS: Assessment of lesser or doubtful degrees of gastric atrophy can be difficult, especially in the antrum, since well established criteria are lacking. At the Houston Working Party on Gastritis in 1994 a visual analogue scale was designed for the grading of histopathological parameters. This was done to promote uniformity in grading by acting as a reference. The purpose of the present study was to measure interobserver variation between pathologists familiar with the Houston visual analogue scale in a specifically selected set of biopsies from patients with lesser or doubtful degrees of atrophy. METHODS AND RESULTS: Thirty cases with biopsies of the antrum and corpus from a long-term follow-up study on Helicobacter pylori gastritis comprised the current study material. The cases were selected from that study because there had been uncertainty or disagreement on the presence of gastric atrophy. The study set of haematoxylin and eosin (H & E) slides was circulated amongst gastrointestinal pathologists familiar with the visual analogue scale who were unaware of the source of the study set nor had any other clinical information. Interobserver variability was analysed using kappa statistics. The overall agreement for the grade of atrophy in antral biopsies was 0.461; the kappa value was 0.18 (95% confidence limits 0.12-0.24), which is considered poor agreement. The kappa value was nevertheless statistically significant (P < 0. 01). The overall agreement on the grade of atrophy in the corpus biopsies was apparently good (0.833), but the kappa which adjusts for chance agreement was only moderate (0.48; 95% confidence limits 0.42-0.55; P < 0.001). CONCLUSION: The studied series comprised a self-selected sample in which there was doubt about the grade of atrophy and such a sample will produce lower kappa values than a random sample of gastric biopsies. The results nevertheless confirm that better guidelines and firm criteria are needed to properly diagnose and grade gastric atrophy. It is suggested that the use of two grades, low- and high-grade atrophy, akin to that in use for grading inflammatory bowel disorder (IBD)- associated dysplasia, could improve agreement. Furthermore optimal biopsy quality with full thickness mucosa and proper orientation appears important for grading gastric atrophy.

Atrophy↗
PubMed1999

Antibodies against Helicobacter felis in sera of cats and dogs.

Serum samples from 61 dogs and 49 cats were screened for circulating antibodies against Helicobacter felis by an enzyme-linked immunosorbent assay (ELISA) using sonicated bacteria as an antigen. To improve the specificity of the ELISA, sera were absorbed with Campylobacter jejuni subsp. jejuni H. pylori as well as H. felis. Sera from 26 dogs (43%) and 19 cats (39%) revealed clear positive absorbance readings determined as an optical density (OD) that was statistically significant above the OD mean value [P < 0.025 (one-tailed); log10]. The absorbance pattern of ELISA-positive sera corresponded to results obtained with bovine and human reference sera. Furthermore, a correlation between the immune response and results from histopathological examination of gastric specimens from 22 dogs was demonstrated. It could be shown that antibodies against H. felis in sera of cats and dogs can easily be detected using an ELISA. The diagnostic value of this test must be evaluated in further investigations.

Animals↗
PubMed1999

Local treatment of early cancer in short Barrett's esophagus by means of argon plasma coagulation: initial experience.

In recent years endoscopically controlled local therapeutic methods, such as photodynamic therapy, mucosectomy, or laser therapy, have been used with a curative aim for the destruction of early esophageal or gastric cancers. We report on our experience of treating histologically proven mucosal cancer in Barrett's esophagus with argon plasma coagulation (APC), in three patients. All the mucosal esophageal cancers, with a mean diameter of 4 mm, were successfully destroyed after one or two treatment sessions. Additionally, in two of the three patients the specialized columnar epithelium was replaced by normal squamous cell epithelium when APC treatment was combined with omeprazole. In the third patient with Barrett's esophagus, a partial squamous cell re-epithelialization was induced. No method-related mortality and morbidity were observed. During the mean follow-up of 24.3 +/- 1.1 months (range 23-25 months) one tumor recurrence developed which was successfully treated with photodynamic therapy. In patients with small early Barrett's carcinoma APC might offer an effective, minimally invasive alternative to mucosectomy or photodynamic therapy, as the treatment procedure is less cumbersome and the equipment less expensive.

Adenocarcinoma↗
PubMed1999

Short Barrett: prevalence and risk factors.

BACKGROUND: The incidence of adenocarcinoma at the gastro-oesophageal junction is on the increase. These carcinomas are usually diagnosed too late and thus have a poor prognosis. Only early diagnosis can improve the situation. Classical Barrett oesophagus (length, >3 cm) is a known precancerous condition. There is also specialized columnar epithelium (SCE) in the grossly unremarkable gastro-oesophageal transitional zone (short Barrett). METHODS: To determine the frequency of SCE, 370 patients were investigated by gastroscopy (OGD) consecutively between September 1995 and February 1996. RESULTS: Classical Barrett oesophagus was found to have an incidence of 4.6%. In contrast, microscopic evidence of SCE was observed in 13.6% of the cases. Patients with short Barrett presented with reflux symptoms (odds ratio (OR), 4.7), irregular zona serrata ('tongues') in the cardia (OR, 2.8), and reflux oesophagitis significantly more frequently. Patients with reflux symptoms and concomitant 'tongues', however, had an OR of 13.16. Careful history-taking, together with a subtle histologic work-up of the gastro-oesophageal transitional zone can improve the rate of detecting patients with short Barrett. CONCLUSION: Patients with reflux symptoms and irregular zona serrata should be selectively biopsied at the gastro-oesophageal junction, even when the latter presents a grossly normal appearance, with the aim of detecting patients at risk of developing a Barrett carcinoma.

Adenocarcinoma↗
PubMed1999

Leptin and its receptor in normal human gastric mucosa and in Helicobacter pylori-associated gastritis.

BACKGROUND: Leptin, a newly discovered weight-reducing hormone, is mainly produced in fat cells. Recently, this hormone has been reported to be produced in rat gastric mucosa cells. In the present study we analyzed the localization and expression of leptin and its receptors in normal human gastric mucosa and in patients with Helicobacter pylori-associated gastritis. METHODS: Plasma leptin levels and gastric mucosa leptin content were determined in 39 patients with dyspepsia. Cellular localization of leptin and of the signaling receptor (Ob-RL) were assessed by immunohistochemistry. Reverse transcriptase polymerase chain reaction (RT-PCR) for leptin receptor isoforms was performed on gastric epithelial cells isolated by laser-capture-microdissection. RESULTS: Leptin content of the corpus gastric mucosa in H. pylori-positive patients was significantly increased (4.6+/-1.2. n = 15) as compared with the H. pylori-negative group (27.5+/-0.5 pg/mg, n = 24, P = 0.006). The presence of leptin immunoreactivity was shown in the lower half of corpus epithelial glands. By RT-PCR no leptin mRNA was detectable in human gastric tissue. In contrast, expression of both Ob-R(L) and the leptin receptor isoforms could be detected in gastric epithelial cells. Leptin receptor protein was detected throughout the mucosa. CONCLUSIONS: Leptin itself is stored and secreted but not produced in human gastric mucosa. The functional receptor and all isoforms are present in human gastric mucosa. H. pylori-associated gastritis leads to significant increases in local leptin concentration in the gastric corpus.

Analysis of Variance↗
PubMed1999

Gastritis associated with Crohn disease can be masked by Helicobacter pylori gastritis.

BACKGROUND: Crohn disease (CD) is typically associated with focal inflammatory infiltrations. It is, however, unclear to what extent this CD-associated gastritis is masked by Helicobacter pylori gastritis. METHODS: One hundred and three patients with CD underwent upper endoscopy. Antrum and corpus biopsy specimens were obtained and histologically evaluated for the presence of CD gastritis or H. pylori gastritis. In patients infected with H. pylori, eradication of the organism was initiated with repeated endoscopy/histology 7 days after termination of therapy. RESULTS: Thirty patients were infected by H. pylori. Definite diagnosis of CD gastritis was made in 4 patients, in contrast to 31 of the 73 patients with no H. pylori gastritis (P < 0.001). In 19 patients with either no (n = 13) or only suspected diagnosis of CD gastritis (n = 6), elimination of H. pylori enabled definite diagnosis of CD gastritis in 5 of 13 and 4 of 6 patients, respectively. CONCLUSION: Elimination of H. pylori facilitates the diagnosis of CD gastritis.

Adult↗
PubMed1999

Aberrant esophageal HLA-DR expression in a high percentage of patients with Crohn's disease.

Esophageal histology is not well studied in patients with Crohn's disease (CD). We, therefore, analyzed the histologic and immunohistologic appearance of esophageal mucosa in CD. Biopsy specimens taken from the esophagus of 57 consecutive patients with known CD of the large and/or small bowel, of 200 Crohn's-free controls, of 15 cases with ulcerative colitis, and of 5 cases with viral esophagitis were evaluated. In controls, most patients had either HLA-DR negative esophageal epithelium or showed focal or diffuse basal staining. HLA-DR expression of all epithelial layers (transepithelial staining) was observed in only four (2%) control subjects, in one case with herpes esophagitis, but not in patients with ulcerative colitis. In contrast, transepithelial HLA-DR expression was found in 19 (33%) patients with CD (p < 0.0001). In CD patients, it was associated with a significantly increased epithelial content in T-cells (CD3+, TIA-1+, granzyme B+), B-cells (CD79a+), natural killer cells (CD57+), and macrophages (CD68+). There was no correlation with either histological findings elsewhere in the upper gastrointestinal tract or with laboratory findings, symptoms, CDAI, or medication. Transepithelial esophageal HLA-DR expression is common in CD. Immunohistochemistry may prove useful in supporting the histologic diagnosis of CD in staging procedures, for initial diagnosis as well as in doubtful cases.

Adolescent↗
PubMed1999

Helicobacter pylori gastritis of the gastric cancer phenotype in relatives of gastric carcinoma patients.

OBJECTIVE: Infection with Helicobacter pylori is associated with gastric cancer. However, a hereditary risk of gastric cancer has also been reported. Hence, we decided to evaluate H. pylori gastritis in relatives of gastric cancer patients in comparison with matched controls. DESIGN: Case-controlled study. METHODS: A total of 237 patients with merely H. pylori gastritis (i.e. not associated with either peptic ulcer or gastric malignancy), and either first-degree (93.7%) or second-degree (6.3%) relatives with gastric cancer, were age- and sex-matched with 237 patients with H. pylori gastritis unassociated with a family history of gastric cancer. From each patient, antral and corpus biopsy specimens were obtained and investigated for degree (lymphocyte/plasma cell infiltration) and activity (polymorph infiltration) of gastritis (score: 0-4). Intestinal metaplasia was recorded as present or absent. RESULTS: The results show that relatives of gastric cancer patients have a significantly greater expression of gastritis due to a higher grade of gastritis in the antrum and corpus (P < 0.0001) and a greater activity of gastritis in the corpus (P < 0.0001). Intestinal metaplasia occurs more often in relatives of gastric cancer patients (antrum: P < 0.0001; corpus: P = 0.0237). CONCLUSION: Since the grade of H. pylori gastritis in relatives of gastric cancer patients is significantly higher than in controls, there appears to be a genetic susceptibility influencing the expression of H. pylori gastritis.

Adult↗
PubMed1999

Immunnohistological assessment of intestinal eosinophil activation in patients with eosinophilic gastroenteritis and inflammatory bowel disease.

OBJECTIVE: To assess the activation grade of intestinal eosinophils in patients with eosinophilic gastroenteritis (EOG), ulcerative colitis (UC), Crohn's disease (CD), and controls by immunohistochemistry. METHODS: Cecal biopsies were collected from healthy controls and from patients with EOG, CD, UC, and other noninflammatory GI diseases. Immunohistochemistry was performed in sequential sections stained with monoclonal antibodies directed against eosinophil cationic protein (ECP) or eosinophil protein X (EPX) stored in eosinophil granules (EG1) and that secreted by activated eosinophils (EG2). The ratio of EG1 to EG2-positive eosinophils expressed as percentage of lamina propria cells was calculated. ECP and EPX were measured in serum and feces. RESULTS: The percentage of EG1 and EG2-positive lamina propria cells was elevated in EOG and slightly, but not significantly, in UC. The ratio of EG1 to EG2-positive cells was decreased in CD, UC, and other patients as compared to healthy controls. Particularly low EG1 to EG2 ratios were found in EOG. Correspondingly, fecal and serum levels of ECP and EPX, respectively, were highest in patients with EOG. The EG1 to EG2 ratio was negatively correlated with fecal ECP and EPX levels. At sites of actively inflamed mucosa, the EG1 to EG2 ratio was lower than in noninflamed tissue. CONCLUSIONS: Our data strongly suggest that the EG1 to EG2 ratio may be a marker of tissue eosinophil activation. Low ratios (<1) indicate eosinophil activation, whereas ratios > or =1 are found in healthy controls. Furthermore, we show that EOG is characterized by a pronounced intestinal eosinophil accumulation and activation, whereas in CD and UC, eosinophils seem to be activated but their number is not or only slightly elevated compared to controls.

Adult↗
PubMed1999

Dual versus triple therapy of Helicobacter pylori infection: results of a multicentre trial.

OBJECTIVE: To compare dual therapy (omeprazole and amoxicillin) with triple therapy (omeprazole, amoxicillin, and clarithromycin) in the treatment of Helicobacter pylori infection. The efficacy of 1 mg/kg/day omeprazole was randomly compared with 2 mg/kg/day. STUDY DESIGN: 252 patients (median age, 11.0 years; range, 3-18) presenting with chronic abdominal pain underwent endoscopy and a 13C-urea breath test. Gastric biopsy specimens were taken for histological examination and for the rapid urease test. Patients were treated for two weeks: group A (n = 63) received amoxicillin (50 mg/kg; maximum, 2 g/day), group B (n = 73) received amoxicillin and clarithromycin (20 mg/kg; maximum, 1 g/day). Both groups were randomly treated with either 1 or 2 mg/kg omeprazole (maximum, 80 mg/day). Diagnostic procedures were repeated four weeks after the end of treatment. RESULTS: 11 patients were excluded; 136 patients were H pylori positive (56%), 105 of whom were re-examined after treatment. Helicobacter pylori was eradicated in 52% of group A and 83% of group B. The dose of omeprazole had no influence on the eradication rate. Specificity and sensitivity of the rapid urease test were 94% and 93%, respectively. Specificity and sensitivity of the 13C-urea breath test were 93% and 95%, respectively. CONCLUSIONS: Dual therapy can no longer be recommended. Triple therapy is more effective than dual therapy in the eradication of H pylori infection. The lower dose of 1 mg/kg omeprazole was as effective as 2 mg/kg.

Adolescent↗
PubMed1999

Simultaneous MALT-type lymphoma and early adenocarcinoma of the stomach associated with Helicobacter pylori gastritis.

We report about two cases of combined gastric lymphoma and gastric carcinoma with one of them representing a case of early gastric high grade B-cell lymphoma of mucosa-associated lymphoid tissue (MALT) with co-existing early gastric adenocarcinoma. In contrast to most previously reported similar cases, in both of our cases the definitive diagnosis of gastric lymphoma and carcinoma was obtained preoperatively. This, however, seems to be in future times an essential prerequisite for employing minimal invasive methods such as eradication therapy in the case of diagnosed early lymphoma and endoscopic treatment for early gastric carcinomas. These methods have been proven to be an effective and beneficial alternative treatment especially with regard to the life quality of the patients.

Adenocarcinoma↗
PubMed1999

Frequent 4-bp deletion in exon 9 of the SMAD4/MADH4 gene in familial juvenile polyposis patients.

Familial juvenile polyposis (FJP) is a hamartomatous polyposis syndrome characterized by the appearance of juvenile polyps in the gastrointestinal tract. Patients with this syndrome are at an increased risk for cancer of the colon, stomach, and pancreas. Recently, germline mutations in the SMAD4/DPC4 gene (official symbol MADH4) have been found in the majority of patients suffering from FJP. We have examined 11 unrelated patients with FJP for MADH4 germline mutations by direct sequencing of genomic DNA encompassing all 11 exons of the gene. Besides a novel mutation (959-960delAC at codon 277, exon 6) in one patient, we observed a 4-bp deletion (1372-1375delACAG) in exon 9 in two unrelated patients. Examination with microsatellite markers flanking MADH4 supports an independent origin of the mutation in these two families. The same 4-bp deletion in exon 9 has previously been described in three out of nine patients examined for MADH4 mutations. Our results combined with these previous data demonstrate that a unique 4-bp deletion in exon 9 of MADH4 accounts for about 25% of all FJP cases and that other MADH4 mutations occur in an additional 15% of patients. Genes Chromosomes Cancer 25:403-406, 1999.

Adenomatous Polyposis Coli↗