Gastroenterology and Hepatology from Bed to Bench

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Aim: The aim of this systematic review was to evaluate the current reported efficacy and the mortality rate of SEMS treatment in uncontrolled bleeding patients.

 Background: Esophageal variceal bleeding (EVB) represents a life threatening pathology. Despite the adequate pharmacologic and endoscopic treatment, continuous or recurrent bleeding, named as uncontrolled bleeding, occurs in 10-20% of cases. A new removable, covered, and self-expanding metal stent (SEMS) was proposed to control the variceal bleeding.

Materials and methods: The study was conducted according to the PRISMA statement. Studies were identified by searching MEDLINE (1989-present) and SCOPUS (1989-present) databases. The last search was run on 01 July 2015.

Results: Nine studies (period range=2002-2015) met the inclusion criteria and were included in quantitative analysis. High rate of SEMS efficacy in controling acute bleeding was observed, with a reported percentage ranging from 77.7 to 100%. In 10% to 20% of patients, re-bleeding occurred with SEMS in situ. Stent deployment was successful in 77.8% to 100% of patients while 11 to 36.5% of patients experienced stent migration.

Conclusion: SEMS could be effective and safe in control EVB and can be proposed as a reliable option to ballon tamponed for patient stabilization and as a bridging to other therapeutic approach. 

Cancer registration is an important source for measuring the burden of cancer in a population. In practice, however, quite frequently incorrect patients are registered or data items can be inaccurately recorded or not recorded at all. Also the process or quality of these registrations varies among countries. In this paper, we briefly discussed some statistical techniques including; Mortality and Incidence Analysis Model (MIAMOD), Prevalence and Incidence Analysis Model (PIAMOD), Bayesian Inference and Capture-recapture methods, which provide tools to re-correct the incomplete or misclassified cancer statistics with regards to gastrointestinal cancers. 

Aim: The aim of this study was to evaluate the likelihood ratio and frequency of DQ2 and DQ8 in Iranian patients with celiac disease (CD).

Background: The HLA DQ2 and HLA DQ8 are the important mediators in the development of celiac disease. A few studies evaluated the frequency of HLA DQ2 and HLA DQ8 haplotypes among the Iranian population with low sample size.

Patients and methods: In this cross-sectional study, to predict HLA–DQ2 and DQ8 haplotypes, 141(73 male, 78 female) confirmed CD patients compared to 151 healthy controls were enrolled into this study during 2013-2014. HLA DQ2/ DQ8 haplotypes was determined in cases and controls using PCR-SSP technique.

Results: DQ2 and DQ8 were positive in 80% (n=111) and 49% (n= 69) of CD patients and 36% (n=61) and 13% (n=21) of control group respectively. Moreover, 32% (n=45) of CD patients and 5.3% (n=8) of the control group were carrier of both haplotypes. In the case group about one-third of patients (32.2%) were positive for carrying both DQ2 and DQ8 heterodimers while only 5.3% (n=8) of the control group were carrier. In addition, the positive likelihood ratio of DQ2 and DQ8 were 1.74 (CI: 1.4- 2.1), and 2.6 (CI: 1.8– 2.7), respectively.

Conclusion: The result of this study showed that the frequency of DQ8 among our population is higher than those reported by European countries, but it is close to those founded in South America and Middle East. This result suggests that the higher prevalence of HLA DQ8 pattern in Iranian CD patients is similar to non-European patients

Aim: This study used the OLGA system to characterize the histology pattern of gastritis in dyspeptic outpatients with a mean age of 45 years from regions with different gastric cancer risks.

 Background: Several classification systems have been purposed for understanding the status of the gastric mucosa.  Currently, the Sydney system is the most widely employed. Nevertheless, the applicability of the Sydney system in therapeutic and prognostic areas is a matter of debate. Given this shortcoming an international group of gastroenterologists and pathologists developed a new system named Operative Link on Gastritis Assessment (OLGA).

Patients and methods: In this cross-sectional comparative study the OLGA system was used to characterize the histology pattern of gastritis in 685 dyspeptic patients referring to the department of gastroenterology of a training hospital. 

Results: No significant correlation was found between active inflammation and total OLGA score (P > 0.05). Also, no statistically significant correlation was found between activity and intestinal metaplasia, dysplasia, atrophy, and cancer (P > 0.05). Even though, there is a positive correlation between mild chronic inflammation and total OLGA score, no correlation has been identified between chronicity and dysplasia or cancer (P > 0.05). Nearly, In all cases with no dysplasia OLGA score was zero but all patients with gastric cancer OLGA score was more than two.

Conclusion: Generally, the activity is not a useful factor in predicting prognosis and its loss of relation with total OLGA score does not make OLGA score any less predictable. 

Aim: The purpose of this study was to determine the efficacy of Heller myotomy for the treatment of achalasia in a referral center in Tehran, and investigate the clinical characteristics, manometric results and treatment responses among three achalasia subtypes in Iranian patients.

 Background: Esophageal achalasia is an unusual swallowing disorder, characterized by high pressure in the lower esophageal sphincter (LES) on swallowing, failure relaxation of the LES and the absence of peristalsis in esophageal.

Patients and methods: In this cross sectional study, clinical symptom and esophageal manometry before and 2 months after treating with Heller myotomy in 20 patients with achalasia who were referred to Taleghani Hospital, Tehran, in 2013 were evaluated. Patients’ demographic, clinical features and response to treatment were analyzed using SPSS software (version 20, Chicago, IL, USA).

Results: All the diagnostic criteria measured after the treatment were significantly different (P<0.05) before and after the therapy. The average decline in the length of the esophagus was 1.8 cm and dysphasia score was 7.25 units. Also an average decline in LES Resting Pressure, LES Residual Pressure, PIP, and IRP were 23.2 mmHg, 14.3 mmHg, 3.4 mmHg and 17.8 mmHg, respectively.

Conclusion: Results of this study showed that the Heller myotomy is highly effective in relieving dysphasia in patients with achalasia. Also, type II achalasia is the most common subtype of achalasia with a better response to Heller myotomy compared to the other types. 

Aim: The aim of this study is to evaluate the polymorphism in Bax gene and its association with some clinical pathology traits in gastric cancer.

 Background: Gastric cancer is considered as the fourth most common cancer in the north and northwest of Iran. Bcl2 family has a key role in regulation of apoptosis, and any changes in the expression of Bcl2 lead to cancer.

Patients and methods: Blood samples were collected from 100 cases and 89 controls in the northern provinces of Iran to evaluate promoter polymorphism (-248G<A) of Bax gene. Genotyping was carried out by PCR-RFLP method.

Results: The result of this study demonstrated the existence of polymorphism in the above-mentioned region of Bax gene. Sixty-nine patients (%69) with genotype GG and 31 patients (%31) with genotype AG were observed in the case group. No mutant genotype was found among cases. Sixty-seven individuals (%75/28) with genotype GG, 21 individuals (%23/59) with genotype AG and only one mutant genotype (AA) were demonstrated in the control group. The bioinformatics analysis showed that this polymorphism removed the probable Sp1 motifs, which may affect its expression in the cells.

Conclusion: Allele G was the most frequent between both patient and control samples. Polymorphism may be effective on Bax expression, but it requires further investigation. Our results showed significant effects between genotypes and features of gender and age, whereas no significant relation were observed between the genotypes and grade, stage as well as smoking traits. 

Aim: To induce acute colitis progresses to chronicity in C57BL/6 mice by dextran sulfate sodium.

 Background: Murine models are essential tools to understand IBD pathogenesis. Among different types of chemically induced colitis models, the dextran sulfate sodium (DSS)-induced colitis model is the most common model of IBD, due to its simplicity.

Patients and methods: Male C57BL/6 mice 6–8 weeks old, were collected and matched by age with controls. C57BL/6 mice treated with 2 cycles of 3.5% DSS for 4 days and 4 days of pure water between each cycle. After that, mice were sacrificed and the entire colon was removed. Small sections of the colon were fixed in formaldehyde, embedded in paraffin and sectioned with a microtome. Sections were stained with hematoxylin eosin to analyses the degree of inflammation.

Results: After the first cycle oral administration of DSS, mice with severe and visible rectal bleeding and diarrhea entered into the acute phase. After day 4-5, bleeding and diarrhea were improved and mice entered into the chronic phase with peak levels of weight loss. Macroscopically, the inflammation was predominantly located in the distal colon. Microscopically, examination of the distal colon sections showed a decrease number of goblet cells, loss of crypts, signs of surface epithelial regeneration and moderate to severe infiltration of inflammatory cells in the mucosa.

Conclusion: In order to achieve an experimental colitis model, our protocol is recommended for future therapies in IBD experimental modeling. 

Aim: The purpose of this study was to investigate the prevalence of enteropathogenic Escherichia coli (EPEC) and shiga toxin producing E. coli (STEC) strains in healthy broilers in Iran.

 Background: STEC and EPEC strains as diarrheagenic E. coli are among the most prevalent causative agents in acute diarrhea. Domestic animals, mainly cattle and sheep, have been implicated as the principal reservoirs of these pathotypes; however their prevalence among the broilers is varied among different countries.

Patients and methods: A total of 500 cloacal swab samples from broilers of five different poultry houses (A-E) were collected to investigate the presence of stx1, stx2, hly, eae, and bfp virulence genes among the E. coli isolates by polymerase chain reaction. The shiga toxin encoding strains were evaluated serologically to detect their interaction with a commercial antiserum against O157 antigen.

Results: Out of the 500 collected samples, 444 E. coli strains were isolated. Three strains (0.67%) presented at least one of the studied virulence genes (stx2, hly and eae), two strains were identified as STEC (stx2⁺, O157:nonH7) and one as an atypical EPEC strains (eae⁺bfp^-).

Conclusion: The study established the presence of STEC and atypical EPEC in healthy broilers in Iran. Poultry might serve as vectors for transmission of pathogenic E. coli to human populations. 

Cronkhite- Canada syndrome (CCS) considered as a rare and non-hereditary disorder. Gastrointestinal polyposis and diarrhea along with some extra signs and symptoms such as hypoproteinemia, and epidermal manifestations are recognized in this syndrome. The pathophysiology of this syndrome is not completely understood and it seems that inflammatory processes may be involved. We present a 50 year-old man with hamartomatous polyps throughout the colon and long-lasting diarrhea not responding to typical therapies during three years. 

A common belief is that alkali ingestion causes severe esophageal damage and limited gastric injury due to the buffering action of acid. Gastric injury has been observed in patients who ingested alkali. Gastric outlet obstruction (GOO) secondary to caustic ingestion occurs due to fibrosis after resolution of the acute injury and inflammation, most commonly 6 to 12 weeks after initial ingestion. The traditional treatment for GOO related to ingestion of corrosive agents is surgery. Experience with endoscopic balloon dilation of corrosive-induced GOO is limited in children. This is the first report of endoscopic pyloroplasty in a child with GOO due to caustic alkalis ingestion that was treated with balloon dilation (using TTS balloon ranging from 6-15 mm) in Iran. Four dilation sessions were required for symptomatic relief of dysphagia. After one year of follow up, weight gain was normal. 

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