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INTRODUCTION: The clinical relevance of bacterial types identified in small bowel aspirate cultures during diagnostic evaluation of small intestinal bacterial overgrowth (SIBO) is unclear. AIM: The main purpose of this study was to assess associations between risk factors for upper aerodigestive tract (UAT) or coliform SIBO and SIBO diagnosis by culture. MATERIALS AND METHODS: Small bowel aspirates were cultured in patients with suspected SIBO, defined as ≥10 colony-forming units/mL coliform or ≥10 colony-forming units/mL UAT bacteria. History was reviewed for risk factors and potential SIBO complications. Symptoms, quality of life, psychological traits, and laboratory values were assessed. We compared groups by 2-sample t test, Wilcoxon rank sum test, and the Fisher exact test. Overall associations of primary and secondary endpoints with type of bacterial overgrowth were assessed by analysis of variance F-test, Kruskal-Wallis test, and the Fisher exact tests. Associations of risk factors with type of overgrowth were explored using multinomial logistic regression. RESULTS: Among 76 patients, 37 had SIBO (68% coliform, 33% UAT) and 39 did not. Conditions (P=0.02) and surgery (P<0.01) associated with decreased gastric acid were associated with SIBO. In multinomial logistic regression, conditions of decreased acid was associated with UAT SIBO [odds ratio (OR), 5.8; 95% confidence interval, 1.4-33.3]. Surgery causing decreased acid was associated with UAT [OR, 9.5 (1.4-106)] and coliform SIBO [OR, 8.4 (1.6-86.4)]. Three patients with discontinuous small bowel had coliform SIBO [OR, 17.4 (1.2-2515)]. There were no differences in complications, overall symptoms, quality of life, or psychological traits. CONCLUSIONS: Conditions or surgeries associated with decreased gastric acid are associated with SIBO diagnosis by culture.

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OBJECTIVES: The composition of the small intestinal microbiota has not yet been characterized thoroughly using culture-independent techniques. We compared small intestinal microbial communities in patients with and without small intestinal bacterial overgrowth (SIBO) using culture-dependent and culture-independent bacterial identification approaches. METHODS: Small bowel aspirate and mucosal samples were collected from patients with suspected SIBO. The aspirates were cultured to diagnose SIBO, defined as ≥10 colony-forming units/mL coliform or ≥10 colony-forming units/mL upper aerodigestive tract bacteria. Bacteria in the aspirates and mucosa were identified using 16S rRNA gene sequencing. We compared small intestinal microbiome composition between groups with and without a culture-based SIBO diagnosis. RESULTS: Analysis of the aspirate and mucosal microbial communities from 36 patients revealed decreased α-diversity but no differences in ß-diversity in patients with SIBO compared with those without SIBO. There were no significant differences in the relative abundance of individual taxa from the aspirates or mucosa after adjustment for false discovery rate between patients with and without SIBO. Subgroup analysis revealed significant differences in mucosal ß-diversity between the coliform and upper aerodigestive tract subgroups. Relative abundances of a mucosal Clostridium spp. (P = 0.05) and an aspirate Granulicatella spp. (P = 0.02) were higher in coliform SIBO vs non-SIBO subgroups. The microbial composition and relative abundance of multiple taxa significantly differed in the mucosal and aspirate specimens. DISCUSSION: Culture-based results of small bowel aspirates do not correspond to aspirate microbiota composition but may be associated with species richness of the mucosal microbiota.

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BACKGROUND: Excessive drinkers (ED) and patients with alcoholic liver disease (ALD) are several times more susceptible to bacterial and viral infections and have a decrease in antibody responses to vaccinations. Follicular helper T (TFH) cells are essential to select B cells in the germinal center and to produce antibodies. TFH cells express both a membrane-associated and a soluble form of CD40 ligand (sCD40L); in which the latter form is released to circulation upon T cell activation. The effect of alcohol on TFH cells has not been studied. OBJECTIVES: The goals of this study are to determine the levels of TFH and T helper 1 (Th1) cells in ED and those with alcoholic cirrhosis (AC) when compared to healthy controls and to determine the prognostic significance of sCD40L in a cohort of patients with AC. METHODS: Controls, ED, and those with AC were enrolled. Baseline demographic, laboratory tests, and peripheral blood mononuclear cells (PBMCs) were isolated and assessed via flow cytometry for TFH cells. In vitro study was performed to determine the ability of PBMCs to secrete interferon (IFN)-γ upon stimulation. Serum sCD40L were also determined and its prognostic significance was tested in a cohort of AC patients. RESULTS: The levels of circulating TFH (cTFH) cells were significantly lower in peripheral blood of subjects with ED and AC compared to controls (P<0.05). IFN-γ secretion from PBMCs upon stimulation was also lower in ED and those with cirrhosis. Serum sCD40L was significantly lower in ED and AC when compared to that in controls (P<0.0005). Its level was an independent predictor of mortality. CONCLUSIONS: Patients with AC had significantly lower level of cTFH and sCD40L. The level of sCD40L was an independent predictor of mortality in these patients.

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OBJECTIVE: Incidental pancreatic cysts are often detected during abdominal imaging and require follow-up since some have malignant potential. Endoscopic ultrasound (EUS) is highly sensitive for pancreatic diseases, yet the prevalence of incidental pancreatic cysts discovered with EUS is unknown. The objective of the study was to determine its prevalence by EUS. METHODS: A prospective cross-sectional study was conducted. Patients undergoing EUS for nonpancreatic indications and without known pancreatic abnormality were recruited to assess the prevalence of pancreatic cysts and its characteristics. Risk factors were determined by logistic regression. RESULTS: We enrolled 341 patients (mean age, 59 years; 187 females) and found 46 incidental pancreatic cysts (median [range], 5 [2-80] mm) in 32 patients (9.4%). Branch duct intraductal papillary mucinous neoplasm was the most common finding. Seven cysts were larger than 1 cm and 1 adenocarcinoma was discovered. Multivariate logistic regression showed an association between pancreatic cysts and older age (odds ratio, 1.04 per year; 95% confidence interval, 1.01-1.08) and female sex (odds ratio, 3.08; 95% confidence interval, 1.25-7.45). CONCLUSIONS: In our population, the prevalence of incidental pancreatic cyst discovered on EUS was 9.4% and the majority were less than 1 cm. Increasing age and female sex were associated with the development of pancreatic cysts.

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BACKGROUND: Pancreatic cysts are relatively rare, but constitute an important disease entity that poses a challenge with clinical, radiological, and pathological differential diagnosis. METHODS: New attention has been drawn to pancreatic cysts given their potential cure rates with resection. However, preoperative distinction between neoplastic and benign lesions needs further study for effective strategies in identification and management. The role and safety of cystic fluid analysis remains to be clarified in this context. RESULTS: The presence of mural nodules is a significant indicator for malignancy; however, size as a reliable predictor remains controversial. Specific criteria are required with particular focus on the histologic subtype of pancreatic lesions. CONCLUSION: We review recent developments in the understanding and management of cystic lesions of the pancreas.

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