Relationship between Helicobacter pylori Virulence Genes and Clinical Outcomes in Saudi Patients

Helicobacter pylori has been strongly associated with gastritis, gastric and duodenal ulcers, and it is a risk factor for gastric cancer. Two major virulence factors of H. pylori have been described: the cytotoxin-associated gene product (cagA) and the vacuolating toxin (vacA). Since considerable geographic diversity in the prevalence of H. pylori virulence factors has been reported, the aim of this work was to determine if there is a significant correlation between different H. pylori virulence genes (cagA and vacA) in 68 patients, from Saudi Arabia, and gastric clinical outcomes. H. pylor was recognized in cultures of gastric biopsies. vacA and cagA genes were detected by polymerase chain reaction (PCR). The cagA gene was obtained with 42 isolates (61.8%). The vacA s- and m- region genotypes were determined in all strains studied. Three genotypes were found: s1/m1 (28%), s1/m2 (40%) and s2/m2 (26%). The s2/m1 genotype was not found in this study. The relation of the presence of cagA and the development of cases to gastritis and ulcer was statistically significant (P < 0.05). The study showed a significant correlation between the vacA s1/m2 genotype and gastritis cases, and a significant correlation between vacA s1/m1 genotype and peptic ulcer cases. The results of this study might be used for the identification of high-risk patients who are infected by vacA s1/m1 genotype of H. pylori strains. In conclusion, H. pylori strains of vacA type s1 and the combination of s1/m1 were associated with peptic ulceration and the presence of cagA gene.

Helicobacter pylori - infected patients

The role of helicobacter pylori on gastric carcinogenesis is still nuclear but it is considered to predispose carriers to gastric cancer. The aim of this study is to investigate the relationship between the extent of DNA damage of normal gastric epithelial cells and H. Pylori positive and negative gastritis according to the histological diagnosis. We compared the percentage of cometed cells on the surface of gastric epithelial cells to the cells beneath gastric mucosal cells by the process of serial incubations times. DNA damage was evaluated by the alkaline single cell gel electrophoresis [comet assay] for 52 cases, compared 19 normal individuals with 19 patients of H.Pylori positive and negative gastritis and further 14 mixed cases with different histology grading were tested by comet procedure for detection of the relationship of histological diagnosis with DNA damage [comet percentage]. There was a relationship between the comet percentage and the histological diagnosis. Comet percentages in specimens from case with normal histology were significantly higher than comet percentages in specimen from case with H. pylori positive gastritis. There was a significant increase in the percentage of cometed cells on the surface of gastric epithelial cells in both normal and infected H. pylori cells compared to the same specimen in the subsequent gastric cell layers

Relationship between the Extent of DNA Damage and Gastritis in Normal and Helicobacter pylori-Infected Patients

BACKGROUND/AIMS: The role of Helicobacter pylori in gastric carcinogenesis is unclear, but H. pylori infection is thought to predispose carriers to gastric cancer. The aim of this study was to investigate the relationship between the extent of DNA damage in normal gastric epithelial cells and H. pylori-positive and -negative gastritis according to histological diagnosis. We also compared the percentage of cometed cells on the surface of the gastric epithelial cells to the percentage beneath the gastric mucosal cells using serial incubations times. METHODS: The comet assay is a rapid, efficient and reproducible measure of DNA damage in single cell and it was used in this study. DNA damage was evaluated in 52 cases using alkaline single cell gel electrophoresis (comet assay). Comparisons were made between 19 normal individuals, 19 patients with H. pylori-positive and -negative gastritis and 14 mixed cases with different histology gradings to determine if there was a relationship between histological diagnosis and DNA damage (comet percentage). RESULTS: The comet percentages in specimens from cases with normal histology were significantly higher than the comet percentages in specimens from cases with H. pylori-positive gastritis. In addition, there was a significant increase in the percentage of cometed cells on the surface of gastric epithelial cells in both normal and H. pylori-infected cells compared to the subsequent gastric cell layers of the same specimen. CONCLUSIONS: A relationship between the comet percentage and the histological diagnosis was observed.

Incidence and Antimicrobial Susceptibility of Mycoplasma pneumoniae in Saudi Arabia

Mycoplasma pneumoniae is increasingly recognized as a common and an important pathogen in community-acquired respiratory tract infections (RTIs) and pneumonia, particularly in school-age children and young adults. To determine the incidence and antibiotic susceptibility of M. pneumoniae at the main hospitals in Riyadh, Saudi Arabia, we studied 552 respiratory samples from patients diagnosed with different clinical diagnosis. The isolation, identification, enumeration and antibiotic resistance test for M. pneumoniae were performed using Pneumofast kit. There were 194 patients (35.1%) with current M. pneumoniae infection, mostly among younger age groups, with pneumonia the most common underlying clinical condition. All tested isolates were susceptible to four antibiotics included in the Pneumofast kit, doxycycline, minocycline, ciprofloxacine and erythromycin. The findings suggest that M. pneumonia infection in Saudi Arabia is more common among younger age groups, and pneumonia is the most common underlying clinical condition among patients with M. pneumoniae infection, that cannot be distinguished from other respiratory infections on the basis of clinical and radiographic diagnosis alone.

Seroprevalence of Helicobacter pylori Infection in Large Series of Patients in an Urban Area of Saudi Arabia / 대한소화기학회지

BACKGROUND/AIMS: Helicobacter pylori is present worldwide but few large population studies exist on the epidemiology of the infection in Saudi Arabia. This is an urban based study which was undertaken to determine the prevalence of H. pylori infection among outpatients suffering from gastrointestinal symptoms attending large hospital in Riyadh, Saudi Arabia. METHODS: A validated enzyme-linked immunosorbent assay (ELISA) was used for this study with 5782 samples collected from the outpatients population suffering from gastrointestinal (dyspeptic) symptoms, aged 2 to 82 years. RESULTS: H. pylori seroprevalence was 67% increasing with age. Female shows higher prevalence of H. pylori infection than male. H. pylori infection was more common in patients suffering from epigastric pain. CONCLUSIONS: The seroprevalence rate was higher in female than male. This study shows a high prevalence of H. pylori infection in a large series of patients in an urban area of Saudi Arabia

Patterns of Helicobacter pylori Resistance to Metronidazole, Clarithormycin and Amoxicillin in Saudi Arabia

There are no generally accepted regimens for the treatment of H. pylori infection in patients with gastritis or duodenal ulcers. However, metronidazole based regimens have been reported to be among the most successful. Resistance to metronidazole, clarithromycin, and amoxicillin was determined for 46 clinical isolates of Helicobacter pylori in Saudi Arabia and tested by E test. Of these isolates, 69.5% was resistant to metronidazole (MIC > 8 mg/l), 21% to clarithromycin (MIC > 1 mg/l) and 11% were multiresistant. No resistance to amoxicillin was observed. Resistance to metronidazole was more common in isolates from females than in those form males. In conclusion, the present study demonstrates high metronidazole resistance rate of H. pylori isolates in Saudi Arabia. Regimens containing metronidazole are best avoided. Trials to test other antimicrobial combinations are recommended.

Helicobacter pylori-associated gastric pathological changes in Saudi patients

The relation between Helicobacter pylori [H. pylori] and pathological changes in gastric mucosa ranging from active superficial gastritis to chronic active deep gastritis accompanied with intestinal metaplasia and dysplastic changes to gastric carcinoma of different grades. Two hundred and sixty six [266] gastric biopsies were examined from Saudi patients. At the same time a total of [10] patients with antral gastritis were used as control. The age of the patients ranged from 16 - 58 years old. There was no difference of changes in between. The transition between these changes may be multifactorial processes in which H. pylori may play a part. The findings suggested that gastric cancer may be induced in the disease associated with H. pylori in spite that the etiology of gastric carcinoma has not been clearly identified. Results showed that H. pylori associated chronic gastritis was the associated disease in [8%] of patients with gastric cancer. The remaining [92%] seems to have normal stomach to severe corpus atrophy