A Study of Association between H. Pylori Genotype and Chronic Gastritis.

The prevalence of Helicobacter pylori (HP) infection is very high in Bangladesh. Chronic gastritis due to H. pylori is commonly associated with important gastric diseases such as peptic ulcer diseases or gastric carcinoma and MALT-oma. The natural course of chronic gastritis is HP-associated antral gastritis or pangastritis or rarely atrophies. This study was done to see the association of H. pylori genotypes with chronic gastritis. This observational cross sectional study was carried out at Bangabandhu Sheikh Mujib Medical University from July 2012 to April 2013 to find out the association of H. pylori genotypes with chronic gastritis in dyspeptic patients of Bangladesh. A total of 50 dyspeptic subjects were involved in the study whose upper GI endoscopies were carried out in presence of an experienced endoscopist. During the procedure four biopsies were taken, two from the antrum and two from body of the stomach. Endoscopic diagnosis was categorized into normal and erosive gastritis. Two (one from antrum and one from body) biopsy samples were collected in phosphate buffer saline and PCR analysis carried out by Multiplex PCR assay. Another two were collected in 10% formalin and histopathological examination was done according to updated Sydney system of classification. Among 50 patents only 34 were PCR positive. So, only 34 subjects were included in the study. Among them 21 patients (61.8%) were male and 13 patients (38.2%) were female, with the mean age of 29.91 years. Endoscopy revealed erosive gastritis in 5(14.7%) patients and normal findings in 29(86.3%) patients. Amongst the strains, cagA gene was detected in 58.8% and was not significantly associated with severity of any parameter of chronic gastritis such as H. pylori density, inflammation (mononuclear infiltration), activity (neutrophilic infiltration), atrophy and intestinal metaplasia. All the strains were positive for vacA allele. s1m1 (55.9%) genotype was most predominant. No vacA allele (s1m1, s1m2, s2m1 and s2m2) were significantly associated with severity of chronic gastritis. In this study, H. pylori genotype -cagA, vacA-s1, s2, m1, m2 allele and histological grading of chronic gastritis according to updated Sydney system of classification is identified. This study will identify the genotypes associated with severe gastritis in our country and thereby help us to take appropriate preventive measure. Further study with larger sample size may be carried out to establish proper association between different genotypes and parameters of chronic gastritis.

Histopathological alterations in post-infectious irritable bowel syndrome in Bangladeshi population.

Irritable bowel syndrome (IBS) is the most common gastrointestinal disorder encountered in general practice. Although enormous progress in the pathogenesis of IBS has been made, it is still poorly understood. A significant proportion of patients with IBS, report onset of symptoms following an episode of acute gastroenteritis. Aim of the study was to determine whether post infective irritable bowel syndrome (PI-IBS) has histological or clinical features that are distinct from those of IBS patients with no history of preceding infection. A total of 50 consecutive IBS out patients and 10 healthy control subjects completed a questionnaire detailing symptoms, mode of onset, and previous psychiatry history. All underwent a full diagnostic workup including colonic biopsy and histopathology. Patients were divided according to onset of symptoms into post infectious IBS (PI-IBS, N=18) and non-post infectious IBS (non-PI-IBS, N=32) patients. Diarrhea predominantly occurred more frequently in PI- IBS (70%) than in non-PI-IBS (40%) patients (p<0.05). Histopathological examination of the biopsy specimen from the sigmoid colon of the observed individuals showed a significant increase in the number of chronic inflammatory cells in both groups of IBS patients comparing to the control group (p<0.001). Lymphoid follicles were increased in both groups of IBS patients in comparison to control group (p<0.05). Mast cells were increased in IBS patients comparing to the control group (p<0.05) and it was significantly increased in the PI-IBS patients than the non-PI-IBS patients (p<0.001). Individuals with PI-IBS are clinically distinct subgroup characterized by predominant diarrheal symptoms and increased mast cells compared to those with non PI-IBS.