Gastroenterology and Hepatology from Bed to Bench

Aim:  To evaluate the association of DNMT1 and MGMT amino acid substitution polymorphisms and colorectal cancer in Iranian population.

Background: The MGMT and DNMT1 are two important methyltransferase enzymes. Amino acid substitution polymorphisms in MGMT and DNMT1 genes may be associated with the genetic susceptibility to sporadic colorectal cancer.

Patients and methods: We assessed eight non-synonymous polymorphisms of these two genes by PCR/Pyrosequencing. Our population consisted of 208 individuals with sporadic colorectal cancer and 213 controls. Allele frequencies and genotypes were compared between the cases and controls.

Results: Odds ratios were calculated and there was no association between DNMT1 and colorectal cancer. However, there was a significant association between two polymorphisms with sporadic colorectal cancer; Arg128Gln (OR 5.53, 95%CI 2.58-7.16) and Gly160Arg (OR 3.04, 95%CI=1.48-6.31) of MGMT gene.

Conclusion: This finding could be an accurate indicator of high occurrence of colorectal cancer in Iranian patients.

Aim:  The aim of this study was to investigate the in vitro inhibitory effect of probiotic E.coli Nissle 1917 (EcN) strain against pathogenic bacteria isolated from patients with diarrhea.

Background: Probiotics are viable microorganisms that are shown to have beneficial effects on human health. EcN is a typical example of probiotics; however, there are few reports of it being administered for treatment of diarrhea.

Patients and methods: The inhibitory effect of EcN was assessed against bacteria associated with diarrhea, including 30 diarrheagenic E.coli strains, 10 Salmonella spp, 10 Clostridium difficile and 10 Campylobacter spp, using spot method inoculation. The microcin sensitive strain (E.coli K12 H 5316) was used as control.

Results: In vitro growth inhibition was recorded in none of cultured bacterial samples.

Conclusion: The inhibitory activity of EcN on different bacteria probably relies on different in vivo complementary mechanisms. 

Aim: The present study aimed to compare the eradication rate of H. pylori by traditional amoxicillin, metronidazole, bismuth, and omeprazole regimen, with a new one using clarithromycin, omeprazole and ampicillin/sulbactam (penbactam).

Background: Due to the appearance of Amoxicillin-resistant H. pylori strains all over the world, the decreased efficacy of conventional Amoxicillin-containing treatment regimens has become a matter of concern.

Patients and methods: A total of 332 dyspeptic patients whose H. pylori infection was confirmed by endoscopy and rapid urease test (RUT) were randomized into two groups: group A, comprising 162 patients who received the traditional quadruple treatment regimen for H. pylori (bismuth 240 mg, omeprazole 20 mg, amoxicillin 1gr, and metronidazole 500 mg twice daily) and  group B, containing 170 patients who received clarithromycin 500mg, penbactam (ampicillin 250 mg plus sulbactam 175 mg) and omeprazole 20 mg twice daily. Both groups were given the treatment for 2 weeks, and both underwent UBT 4 weeks after the end of treatment; UBT negative patients were considered responders and the rate of treatment response was compared by per-protocol and intention-to-treat analysis between two groups.

Results: The eradication rate was 56.4% in group A and 87%in group B by per protocol analysis. The eradication rates were 48.8% and 81.7% according to intention-to-treat analysis in groups A and B respectively. The eradication rate was higher in group B patients taking penbactam, omeprazole and clarithromycin (P<0.0001).

Conclusion: Our study showed that using ampicillin/sulbactam instead of amoxicillin, clarithromycin and omeprazole increased the eradication rate of H. pylori significantly.

Aim:  The goal of the present study was to assess the effect of omeprazole on bone mineral density and frequency of osteopenia and osteoporosis.

Background: The effect of omeprazole on bone turnover and the role of stomach pH alteration in calcium absorption have not been completely understood.

Patients and methods: In a case-control study, 58 patients who were referred to Loghman hospital, Tehran, for bone densitometry between July 2005 and July 2006 and were administered omeprazole (20 mg/12hours for at least one month) were entered into the study. The control group comprised 239 matched (for gender, age, weight, history of cigarette smoking, history of milk or egg consumption within the week preceding the study) patients who were not administered Omeprazole. Bone mineral density (BMD) was measured at the lumbar spine (LS) (L2-L4, anterior- posterior position) and hip using dual-energy X-ray absorptiometry (DXA) with a Lunar Prodigy densitometer.

Results: The mean T-score of lumbar spine was not significantly different between patients who received omeprazole and controls (-0.802±1.38 versus -0.808±1.56, P=0.977). Also, mean T-score of hip was similar between patients who received this drug and control group (-0.431±1.050 versus -0.245±1.18, P=0.241). There were also no significant relationships between the consumption of omeprazole and prevalence of osteopenia or osteoporosis.

Conclusion: Short-term administration of omeprazole has no significant influence on bone density and does not increase the incidence of osteopenia and osteoporosis. 

Aim:  The aim of this study was to present the demographic and clinical characteristics of patients with gastric polypoid lesions and to study the histopathologic features of these lesions.

Background: The frequency of gastric polyps is gradually increasing due to the widespread use of endoscopic examinations.

Patients and methods: Clinical and endoscopic features of 100 gastric polyposis patients (with 107 polypectomy specimens) were retrospectively studied. All the specimens were histologically re-evaluated by two pathologists.

Results: 107 specimens of gastric polypoid lesions were identified in 100 patients. There were 73 men and 27 women with a median age of 49 years. The most frequent presenting symptom was dyspepsia (76%). The most common location was  antrum followed by the cardia. The frequencies of hyperplastic polyps, fundic gland and adenomatous polyps were 69.2 %, 6.6 %, and 4.7 % respectively. We also detected an inflammatory fibroid polyp, a carcinoid tumor and a case of leiomyoma in polypoid lesions. In 16.8% of cases histologic evaluation revealed only foveolar hyperplasia, intestinal metaplasia or edematous mucosa. Mild dysplastic changes were observed within three hyperplastic polyps and high grade dysplasia in two adenomas.

Conclusion: Hyperplastic polyps are the most frequently identified gastric polyps in our population. These polyps may contain foci of dysplasia. Presence of these changes as well as other unusual tumors with polypoid appearance can only be confirmed by histological examination. Therefore, endoscopic polypectomy is a safe procedure for both the diagnosis and treatment of gastric polypoid lesions.

Aim:  This study aimed to compare the recurrence rate, mortality, and morbidity of curative resection of distal adenocarcinoma of the stomach between total gastrectomy (TG) and subtotal gastrectomy (STG).

Background: The choice between TG and STG for adenocarcinoma of the lower third of the stomach is still a matter of debate and controversy among surgeons.

Patients and methods: Hospital records of 66 patients with distal adenocarcinoma of stomach, which had undergone even-total or subtotal gastrectomy between October 2001 and February 2006 in Taleghani hospital, Iran were reviewed retrospectively. Demographic data and clinicopathological factors were recorded. Post-operative outcomes including mortality, morbidity and tumor recurrence were assessed. Univariate analyses using Fisher's exact test, the Student t-test, and the Pearson ?² test were used. P values less than 0.05 were considered statistically significant.

Results: Recurrence rate was higher in STG than TG (61% vs. 23%, RR=2.68, 95% CI=1.37-5.24, P=0.002). The mean time interval between gastrectomy and tumor recurrence was not different between TG and STG (19.75±5.1 vs. 18.0±7.8 months, P=0.507). Tumor size >5 cm (P=0.004), diffuse type (P=0.034), poor differentiation (P=0.001) and serosal invasion (P=0.012) were found to be significantly related to tumor recurrence in patients who had undergone gastrectomy.

Conclusion: Subtotal and total gastrectomy techniques have similar surgical outcome and postoperative complication rate; however, STG is associated with a more than twofold increase in local recurrence risk. 

Background: Excess amounts of lead in serum may affect different organ systems and cause lead poisoning. This toxicity mostly happens in chronic and occupational settings. This report comprises the clinical presentation of an acute case of lead toxicity with a much uncommon source of poisoning: opium.

Case Presentation: A 25 year old man was presented to us with abdominal pain, nausea and vomiting, severe weight loss, generalized bone pain, and jaundice. He had six years history of addiction to oral and inhalation forms of opium. Pallor and jaundice were observed in his mucosa and bluish pigmentation was evident at the gum-teeth line. Hepatosplenomegaly and lymphadenopathy were not detected. Upper GI endoscopy was normal. Liver enzymes and indirect billirubin were increased; however, alkaline phosphatase was in normal range. Laboratory tests were indicative of hemolytic anemia without autoimmune origin.  Bone marrow aspiration and biopsy were indicative of erythroid hyperplasia. According to the symptoms and the clinical symptoms of lead poisoning, the lead level was measured both in the serum and in the opium sample the patient used to use. 350mcg/dl of lead in the serum and the very high lead content of the opium sample confirmed the diagnosis; therefore, patient was treated with Calcium-EDTA and BAL that caused decrease of lead level and elimination of symptoms.