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W Dekker

Publications and source records attributed to W Dekker.

At least 37 records · Page 2Linked to original sources
PubMed1994

Does color vision deficiency in the endoscopist influence the accuracy of endoscopic diagnosis? An anonymous study with Dutch gastrointestinal endoscopists.

Colors play a major role in the endoscopic diagnosis of many gastrointestinal conditions. Gastrointestinal endoscopists in the Netherlands are predominantly male (> 90%), and from population data it is to be expected that approximately 8% will have a color vision deficiency. The present study was designed to assess the prevalence of color vision deficiencies amongst Dutch gastrointestinal endoscopists and to determine whether color vision deficiency affects an endoscopist's diagnostic skill. One hundred and thirty-nine gastroenterologists and physicians of internal medicine took an F2 color vision test and assessed nine videofragments of endoscopies. Color vision deficiencies were detected in 8% of Dutch gastrointestinal endoscopists. In one out of the nine video excerpts of endoscopies, a statistically significant difference was detected between test subjects with and without a color vision deficiency. However, this video excerpt showed a green pea, which could not be mistaken for a polyp at polypectomy. The study therefore does not show any effect of color vision deficiencies on endoscopic skills, nor does it show any deviant prevalence of color vision deficiencies amongst Dutch gastrointestinal endoscopists.

Adult↗
PubMed1994

Helicobacter pylori and early gastric cancer.

The relation between Helicobacter pylori, intestinal metaplasia, and early gastric cancer was studied by examining gastrectomy specimens from 31 intestinal type and 22 diffuse type carcinomas. A total of 298 patients with antral gastritis were used as controls. Atrophic changes and intestinal metaplasia were significantly more common in intestinal type early gastric cancer compared with diffuse type early gastric cancer (p < 0.05 and p < 0.001, respectively). H pylori was found in 61.3% of intestinal type early gastric cancer and in 54.5% of diffuse type early gastric cancer (NS). The age adjusted prevalence of intestinal metaplasia in the patients with antral gastritis was higher in H pylori positive patients in all age groups studied. Comparing gastritis patients with patients with intestinal type early gastric cancer showed the age adjusted prevalence of intestinal metaplasia to be significantly higher in the patients with early gastric cancer in all age groups studied. In conclusion, H pylori is associated with both types of early gastric carcinoma. Intestinal metaplasia formation seems to be a multifactorial process in which H pylori may play a part. These findings suggest that gastric cancer may be included in the spectrum of H pylori associated diseases, although many questions about causality remain to be answered.

Adenocarcinoma↗
PubMed1993

Efficacy of famotidine 20 mg twice a day versus 40 mg twice a day in the treatment of erosive or ulcerative reflux esophagitis.

Two different doses of famotidine (20 mg twice a day versus 40 mg twice a day) were evaluated in a double-blind, randomized multicenter study in 474 symptomatic patients with erosive ulcerative reflux esophagitis. A total of 238 patients were treated with famotidine 20 mg and 236 patients with 40 mg at breakfast and dinner-time. Relief of symptoms was significant in all patients after six and 12 weeks and not different in both treatment groups. Overall endoscopic healing was significantly better in the famotidine 40 mg twice a day group compared with 20 mg twice a day at week 6 (58% versus 43%; P < 0.05) and at week 12 (76% versus 67%; P < 0.05). Extending treatment to 24 weeks with 40 mg of famotidine twice a day in those patients not healed after 12 weeks did not result in further symptom relief or in significantly better overall healing. The differences in efficacy of these two doses were more pronounced with increasing severity of esophagitis. Analyzed by grade of esophagitis at entrance, healing was significantly better with famotidine 40 mg twice a day at week 6 for grade II, at week 12 for grades III and IV, and at week 24 for grade IV esophagitis. The results show that in the treatment of erosive/ulcerative reflux patients famotidine 40 mg twice a day is more effective and achieves faster healing than famotidine 20 mg twice a day.

Adolescent↗
PubMed1993

Serum antineutrophil cytoplasmic autoantibodies in inflammatory bowel disease are mainly associated with ulcerative colitis. A correlation study between perinuclear antineutrophil cytoplasmic autoantibodies and clinical parameters, medical, and surgical treatment.

Perinuclear antineutrophil cytoplasmic antibodies have recently been demonstrated in the sera of patients with inflammatory bowel disease. Three hundred and sixty six sera obtained from 120 patients with ulcerative colitis, 105 patients suffering from Crohn's disease and 49 non-inflammatory bowel disease controls were tested in two laboratories, using an indirect immunofluorescence assay. In addition, a fixed-neutrophil enzyme linked immunoadsorbent assay (ELISA) was evaluated in one of the two laboratories. The results in the immunofluorescence test showed a high degree of correlation between the two laboratories (Kappa coefficient = 0.8). Ninety five of the 120 (79%) ulcerative colitis patients had a positive test whereas only 14 of the 105 (13%) patients with Crohn's disease were positive. Sera from four patients suffering from primary sclerosing cholangitis were positive as well as four of the 45 control sera (9%). The sensitivity of the perinuclear antineutrophil cytoplasmic antibody immunofluorescence test for the diagnosis of ulcerative colitis was 0.75 with a specificity of 0.88 and a positive predictive value of 0.88 (all sera). In the ELISA technique 37 of 94 ulcerative colitis sera and one of the 68 Crohn's disease sera were positive. In the control group only one of the patients suffering from primary sclerosing cholangitis reacted positively (32 non-inflammatory bowel disease sera tested). The ELISA technique had a high specificity (0.97), but a low sensitivity (0.39). There was no relation of perinuclear antineutrophil cytoplasmic antibodies in ulcerative colitis patients or in Crohn's disease patients with disease activity, duration of illness, localisation, extent of disease, previous bowel operations or medical treatment. The clinical significance of perinuclear antineutrophil cytoplasmic antibody positive and negative subsets in both groups of patients thus remains unexplained. Our study confirms that determination of serum antineutrophil cytoplasmatic antibodies in patients with inflammatory bowel disease may differentiate ulcerative colitis from Crohn's disease. Further immunological studies are needed to explain the absence of these antibodies in a subset of ulcerative colitis patients and their role in the pathogenesis of the disease.

Adult↗
PubMed1992

Acute noncardiac chest pain in a coronary care unit. Evaluation by 24-hour pressure and pH recording of the esophagus.

Twenty-four-hour recording of esophageal pressure and pH was performed successfully in 41 patients admitted to the coronary care unit of a general hospital who had an episode of acute, prolonged retrosternal chest pain and who were initially suspected of suffering from coronary artery disease (severe angina pectoris, myocardial infarction), but in whom the pain was subsequently shown not to be of cardiac origin. The recordings were analyzed with fully automated techniques. A pain episode was considered to be related to abnormal esophageal motility when contraction amplitudes or durations in the pain episode exceeded the patient's upper limit of normal (97.5th percentile) or when the proportion of abnormal propagated contractions (simultaneous, nontransmitted) in the pain episode was significantly increased (chi 2 test). Thirty patients (73%) had one or more pain episodes (in total 63 pain episodes) during the 24-hour recording. Forty-three percent of the pain episodes was related to abnormal motility and 30% to reflux, and 27% was not related to esophageal function disturbance. Using the criterium that the symptom index had to be greater than or equal to 75%, it was found that the pain was related to reflux in 13 patients (43%) and to motor abnormalities in 10 patients (33%). It is concluded that in the majority of patients acutely admitted with noncardiac chest pain, esophageal motor abnormalities and reflux can be shown to be the likely cause of the symptoms.

Acute Disease↗
PubMed1992

Intestinal metaplasia and Helicobacter pylori: an endoscopic bioptic study of the gastric antrum.

To study the relationship between intestinal metaplasia and Helicobacter pylori infection, 2274 gastroscopic antral biopsies taken from 533 patients were examined. Overall, intestinal metaplasia was found in 135 patients (25.3%) and H pylori in 289 patients (54.2%). The prevalence of intestinal metaplasia and H pylori was age related, being more common in patients greater than or equal to 50 years compared with patients less than 50 years (intestinal metaplasia, p less than 0.001 and H pylori, p less than 0.05). Intestinal metaplasia was found more often in H pylori positive patients compared with H pylori negative patients (33.9% v 15.2%, p less than 0.001). The mean age of intestinal metaplasia positive patients who were also H pylori positive was 64 (13.3) years, whereas the mean age of intestinal metaplasia positive patients who were H pylori negative was 72 (14.7) years (p less than 0.005). The extent of intestinal metaplasia was not statistically different in the latter two groups. Although our data do not prove a causal relationship between H pylori infection and the histogenesis of intestinal metaplasia it is suggested that H pylori infection is an important factor in the development of intestinal metaplasia, which is generally recognised as a precursor lesion of intestinal type gastric carcinoma.

Adult↗
PubMed1992

Subtypes of intestinal metaplasia and Helicobacter pylori.

To determine whether there is a relationship between the presence of H pylori and the various subtypes of intestinal metaplasia in the gastric antrum, 2274 antral gastroscopic biopsies from 533 patients were examined. H pylori was found in 289 patients. Intestinal metaplasia in general was found in 135 patients. Type I intestinal metaplasia was found in 133 patients (98.5%), type II in 106 patients (78.5%) and type III in 21 patients (15.6%). Ninety eight of these 135 patients (72.6%) were H pylori positive and 37 patients (27.4%) were H pylori negative. No statistically significant difference was found in the prevalence of type I and II intestinal metaplasia between the intestinal metaplasia positive and H pylori positive and intestinal metaplasia negative and H pylori negative patients. Type III intestinal metaplasia was found less often in the intestinal metaplasia positive and H pylori positive patients (11.2%) as compared with intestinal metaplasia positive and H pylori negative patients (27%) (p less than 0.05). In contrast with type I and II intestinal metaplasia type III intestinal metaplasia was found more often in moderate/severe intestinal metaplasia than in mild intestinal metaplasia (p less than 0.02). Within the group of patients with moderate/severe intestinal metaplasia, type III was found less often in the H pylori positive patients (p less than 0.05). We suggest that the gastric milieu for H pylori is less appropriate in type III intestinal metaplasia positive patients. As type III intestinal metaplasia might be regarded as a marker of possibly increased gastric cancer risk, the lower prevalence of H pylori in these type III intestinal metaplasia positive patients might be the result of severe changes in mucosal architecture.

Adult↗
PubMed1992

Polyps of the stomach and duodenum: significance and management.

Gastric and duodenal polypoid lesions are almost always diagnosed incidentally and constitute a clinical problem for treatment and follow-up. The histologic types of polypoid lesions in stomach and duodenum are described, as well as the clinical setting in which they are found. Endoscopy and directed biopsies, but particularly diathermic snare polypectomy, are essential to establish a certain histologic diagnosis. Guidelines are given for treatment and follow-up.

Duodenal Neoplasms↗
PubMed1992

Combination therapy of sucralfate and ranitidine, compared with sucralfate monotherapy, in patients with peptic reflux esophagitis.

A double-blind, multicenter, randomized study was performed in 75 patients with endoscopically documented reflux esophagitis. Patients were randomly given 1 g sucralfate four times a day or the combination of sucralfate three times a day and 300 mg ranitidine after dinnertime. Endoscopy was performed at the beginning of the study, after 8 weeks, and, if, the reflux esophagitis was not healed, after 16 weeks. Four patients had to be excluded from evaluation; 71 patients could therefore be evaluated. Both groups showed symptomatic improvement to similar extents. Endoscopy showed symptomatic improvement in 67% of the patients treated with sucralfate and in 74% of the combination therapy group. Complete healing or Savary-Miller stage 1 was seen in 26.5% and in 31.4%, respectively. We conclude that sucralfate monotherapy in patients with milder forms of reflux esophagitis is comparable with a combination of sucralfate during the day and ranitidine after dinnertime. This study does not support the commonly used combination of sucralfate and H2-receptor antagonists in reflux esophagitis.

Adolescent↗
PubMed1992

Time trends in gastric carcinoma: changing patterns of type and location.

To determine whether there have been major changes in various aspects of gastric carcinoma, we reviewed the records of 302 patients with gastric cancer diagnosed between 1973 and 1989. Patients were divided into two groups: group I, 1973-80 (n = 163), and group II, 1981-88 (n = 139). On admission, no significant differences in presenting symptoms and physical signs were found, except for an increase in dysphagia (p less than 0.005) in group II. Endoscopy with targeted biopsy and biphasic-contrast examination were of equal merit in detecting malignancy (99.7%). A significant increase in the proportion of patients with cardia carcinoma was noted in group II (p less than 0.02). The proportion of patients with early gastric cancer decreased from 11% to 7.2%. The proportion of patients with intestinal-type carcinoma decreased in period II (p less than 0.05), accompanied by an increase in the proportion of patients with diffuse-type carcinoma during the same period (p less than 0.01). The overall 5-yr survival estimate was 17%. Independent prognostic variables were T stage (p less than 0.0001) and N stage (p less than 0.001), whereas Lauren type and tumor site were only significant in univariate survival analysis (p less than 0.05 and p less than 0.005, respectively).

Adult↗
PubMed1991

Early gastric cancer: a clinicopathologic study.

We report our experience, between 1973 and 1989 of 302 patients with gastric cancer in a Dutch general hospital. In 144 (47.7%) of them gastric resection was performed. Twenty-eight patients had early gastric cancer (EGC) (9.3% of the entire series and 19.4% of the resected specimens). Multicentricity of EGC was noted in 3 patients (10.7%). The incidence of EGC decreased slightly during consecutive 8-year intervals. There were 16 men and 12 women (mean age 64 and 66 years, respectively). Standard biphasic contrast radiographic studies of the upper gastrointestinal tract diagnosed or suggested malignancy in all but one patient. Endoscopy with directed biopsy diagnosed malignancy in all patients. Twenty-one lesions (67.7%) were localized to the antral region. Type IIc was most frequent (38.7%). There were 21 intestinal-type and 10 diffuse-type EGC by the Lauren classification. The incidence of intestinal-type EGC decreased during two consecutive 8-year periods. All type I and IIa lesions were of the intestinal type, whereas all diffuse-type EGCs were either type IIc or III. Lymph node metastasis was observed in 9.7% of the lesions. The incidence of lymph node metastasis increased from 0% in mucosal cancer to 20% in submucosal cancer. The overall 5-year survival rate was 91.3%: (diffuse type 100% and intestinal type 85.7%). The 5-year survival rate was 100% in mucosal cancer and 81.8% in submucosal cancer.

Adenocarcinoma↗
PubMed1990

Familial occurrence of collagenous colitis. A report of two families.

Collagenous colitis is a rare condition characterized clinically by chronic diarrhea and histologically by a thickened subepithelial collagenous band in colonic biopsies in an endoscopically normal colon. Familial occurrence of collagenous colitis has to our knowledge never been described. Here we report two families in which two first-degree related members suffered from collagenous colitis. In one family, two sisters were affected by chronic diarrhea and autoimmune disorders such as thyroid disease, rheumatoid arthritis, and pernicious anemia. Collagenous colitis was diagnosed in one of these sisters, based on colonic biopsies. Colonic biopsies of the other sister showed microscopic colitis. Review of colonic biopsies of this patient taken 11 years earlier, however, showed definite histological features of collagenous colitis. In the other family, in a father and son, both with diarrhea for several years but not suffering from any other diseases, a diagnosis of collagenous colitis was made on colonic biopsies. Human leukocyte antigen (HLA) typing showed that only the HLA A2 antigen was present in all 4 patients.

Adult↗
PubMed1990

Clinical relevance of gastric and duodenal polyps.

Gastric and duodenal epithelial polyps are almost always diagnosed incidentally and constitute a clinical problem for treatment and follow-up. All histologic types of these polyps are described, as are the clinical settings in which they are found. Endoscopy, often with snare polypectomy, is essential to obtain a certain histologic diagnosis. Guidelines are given for treatment and follow-up.

Diagnosis, Differential↗
PubMed1989

Combination therapy of sucralfate and cimetidine, compared with sucralfate monotherapy, in patients with peptic reflux esophagitis.

A double-blind multicenter, randomized study was performed in 70 patients with endoscopically documented reflex esophagitis. Patients were randomly given 1 g sucralfate four times a day or the combination of sucralfate 1 g three times a day and 400 mg cimetidine at night. After healing of the esophagitis, patients were randomly given either sucralfate maintenance 2 g daily or placebo for a period of six months. Endoscopy was performed at the beginning of the study, after eight weeks, and, in cases with no healing, after 16 weeks of therapy. Sixty-three of the 70 patients who initially entered the study could be evaluated after eight weeks. Both groups showed good symptomatic improvement, and no side effects necessitated withdrawal of subjects. Endoscopy showed complete healing in 19.4 percent of the sucralfate group and in 21.9 percent of the combination sucralfate and cimetidine group. Endoscopic improvement was found in 50 percent of the sucralfate group and in 50 percent of the combination group. After 16 weeks, 56 patients could be evaluated. In the sucralfate group, improvement was seen in 78.6 percent, and healing in 31 percent. For the combination group these values were 59.3 percent and 37 percent (not significant). Twenty-six patients entered the maintenance phase of the study; 15 received sucralfate and 11 received placebo. Evaluation of 20 patients after six months showed endoscopic and/or symptomatic relapse of esophagitis in three of 12 patients receiving sucralfate and in two of the eight patients receiving placebo. It is concluded that sucralfate monotherapy in patients with reflux-esophagitis is effective and comparable with a combination of sucralfate during the day and cimetidine at night. No difference was found between sucralfate and placebo in terms of the relapse rate of esophagitis during long-term treatment.

Adolescent↗
PubMed1989

Treatment failure of norfloxacin against Campylobacter pylori and chronic gastritis in patients with nonulcerative dyspepsia.

Several reports have been published to show the in vitro susceptibility of Campylobacter pylori to different classes of antibiotics, including fluoroquinolones. The purpose of this study was to describe the clinical effect of norfloxacin on eradication of C. pylori in patients with gastritis. Endoscopy was performed in 38 patients with symptoms of nonulcerative dyspepsia. Of these, 20 patients had a C. pylori-positive culture. From this group, 17 patients were treated with norfloxacin for 1 month. After therapy, 15 patients still had positive cultures, and in 9 cases the strain was resistant to norfloxacin. These data, which confirm previous studies, support the concept that the in vitro activity of norfloxacin against C. pylori cannot be transposed to an in vivo effect.

Campylobacter Infections↗