A P Plaisier

Erasmus Universiteit Rotterdam, Rotterdam, South Holland, Netherlands

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Publications (5)51.63 Total impact

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    ABSTRACT: The outcome of Helicobacter pylori infection has been associated with specific virulence-associated bacterial genotypes. The present study aimed to investigate the gastric histopathology in Portuguese and Colombian patients infected with H. pylori and to assess its relationship with bacterial virulence-associated vacA, cagA, and iceA genotypes. A total of 370 patients from Portugal (n = 192) and Colombia (n = 178) were studied. Corpus and antrum biopsy specimens were collected from each individual. Histopathological features were recorded and graded according to the updated Sydney system. H. pylori vacA, cagA, and iceA genes were directly genotyped in the gastric biopsy specimens by polymerase chain reaction and reverse hybridization. Despite the significant differences between the Portuguese and Colombian patient groups, highly similar results were observed with respect to the relation between H. pylori genotypes and histopathology. H. pylori vacA s1, vacA m1, cagA+ genotypes were significantly associated with a higher H. pylori density, higher degrees of lymphocytic and neutrophilic infiltrates, atrophy, the type of intestinal metaplasia, and presence of epithelial damage. The iceA1 genotype was only associated with epithelial damage in Portuguese patients. These findings show that distinct H. pylori genotypes are strongly associated with histopathological findings in the stomach, confirming their relevance for the development of H. pylori-associated gastric pathology.
    American Journal Of Pathology 03/2001; 158(2):647-54. · 4.52 Impact Factor
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    ABSTRACT: Virulence factors of Helicobacter pylori are associated with peptic ulcer disease and may be also associated with the efficacy of treatment. To determine the relation between the vacA and the cagA status of H pylori, clinical disease, and treatment outcome. 121 patients with H pylori infection and peptic ulcer disease or functional dyspepsia were treated by quadruple antibiotic therapy in two groups for one and two days, respectively. DNA was isolated from gastric antral biopsy specimens, taken before and after treatment, and the vacA and cagA status was determined by polymerase chain reaction and reverse hybridisation. Peptic ulcer disease was significantly associated with the vacA s1 type, and cagA positivity, but not with the vacA m type. Treatment efficacy was significantly higher in patients with peptic ulcer disease, or infected with cagA+/vacA s1 strains. The strong association between the cagA and vacA status and peptic ulcer disease was confirmed. Cure rates seem to be higher for patients with cagA+/vacA s1 H pylori strains, which is consistent with the higher cure rate observed among ulcer patients compared with functional dyspepsia patients. Therefore, treatment studies may require stratification for presence of ulcers as well as H pylori genotypes.
    Gut 04/2000; 46(3):321-6. · 10.73 Impact Factor
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    ABSTRACT: BACKGROUND Virulence factors ofHelicobacter pylori are associated with peptic ulcer disease and may be also associated with the efficacy of treatment.AIMSTo determine the relation between the vacA and thecagA status of H pylori, clinical disease, and treatment outcome.PATIENTS121 patients withH pylori infection and peptic ulcer disease or functional dyspepsia were treated by quadruple antibiotic therapy in two groups for one and two days, respectively.METHODSDNA was isolated from gastric antral biopsy specimens, taken before and after treatment, and the vacA and cagAstatus was determined by polymerase chain reaction and reverse hybridisation.RESULTSPeptic ulcer disease was significantly associated with the vacA s1 type, and cagA positivity, but not with thevacA m type. Treatment efficacy was significantly higher in patients with peptic ulcer disease, or infected with cagA+/vacAs1 strains.CONCLUSIONS The strong association between the cagA andvacA status and peptic ulcer disease was confirmed. Cure rates seem to be higher for patients withcagA+/vacA s1H pylori strains, which is consistent with the higher cure rate observed among ulcer patients compared with functional dyspepsia patients. Therefore, treatment studies may require stratification for presence of ulcers as well as H pylori genotypes.
    Gut 01/2000; 46(3):321-326. · 10.73 Impact Factor
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    ABSTRACT: Clinical outcome of Helicobacter pylori infection may be associated with specific virulence-associated bacterial genotypes. The aim of this study was to assess the relationships between H. pylori cagA, vacA, and iceA status and severity of disease. Gastric biopsy specimens from 94 patients in The Netherlands were analyzed by polymerase chain reaction and reverse hybridization. cagA was present in 63 (67%) of 94 cases and was associated with peptic ulcer disease (P = 0.0019). vacA geno-types s1a/m1, s1b/m2, s1b/m1, s1b/m2, and s2/m2 were found in 36.2%, 23.4%, 2.1%, 5.3%, and 20.2%, respectively. Ten isolates (10.6%) contained multiple vacA genotypes. The presence of peptic ulcers was associated with type s1 strains (P = 0.0006) but not with the m type (P = 0.2035). cagA and vacA s1 were strongly associated (P < 10(-5)). iceA1 was found in 53 (56.4%) and iceA2 in 25 (26.6%) of the 94 cases. In 14 isolates (14.9%), both iceA alleles were found, and 2 (2.1%) were negative for both iceA1 and iceA2. iceA1 was also associated with peptic ulcer disease (P = 0.0042). The iceA allelic type was independent of the cagA and vacA status. vacA s1, cagA, and iceA1 are markers of H. pylori strains that are more likely to lead to ulcer disease.
    Gastroenterology 07/1998; 115(1):58-66. · 12.82 Impact Factor
  • Gastroenterology 01/1998; 115(1):58-66. · 12.82 Impact Factor