Effect of the manipulation of the duodenal papilla during double balloon enteroscopy

AIM: To determine the hypothesis that inflating the balloons in the duodenal papilla determines changes in the biochemical markers of pancreatitis.METHODS: Four groups of pigs were used: Group papilla(GP), the overtube's balloon was inflated in the area of the papilla; GP + double balloon enteroscopy(GP + DBE), the overtube's balloon was kept inflated in the area of the papilla for 20 min before a DBE; Group DBE(GDBE), DBE was carried out after insuring the balloon's inflation far from the pancreatic papilla; and Group control(GC). Serum concentrations of amylase, lipase and C-reactive protein(CRP) were evaluated. Pancreases were processed for histopathology examination.RESULTS: Main changes occurred 24 h after the procedure compared with baseline levels. Amylase levels increased significantly in GP(59.2% higher) and were moderately higher in groups GP + DBE and GDBE(22.7% and 20%, respectively). Lipase increased in GP and GP + DBE, whereas it hardly changed in GDBE and in GC. CRP increased significantly in GP, GP + DBE and GDBE, while no changes were reported for GC. No statistically significant difference between groups GP and GP + DBE was found for the histopathological findings, except for vacuolization and necrosis of the pancreatic parenchyma that was higher in GP than in GP + DBE.CONCLUSION: The manipulation of the duodenal papilla by the inflated overtube's balloon during DBE causes pancreatic structural damage and increased biochemical markers associated with pancreatitis.

Proton pump inhibitor resistance, the real challenge in gastro-esophageal reflux disease

Gastro-esophageal reflux disease(GERD)is one of the most prevalent chronic diseases.Although proton pump inhibitors(PPIs)represent the mainstay of treatment both for healing erosive esophagitis and for symptom relief,several studies have shown that up to 40%of GERD patients reported either partial or complete lack of response of their symptoms to a standard PPI dose once daily.Several mechanisms have been proposed as involved in PPIs resistance,including ineffective control of gastric acid secretion,esophageal hypersensitivity,ultrastructural and functional changes in the esophageal epithelium.The diagnostic evaluation of a refractory GERD patients should include an accurate clinical evaluation,upper endoscopy,esophageal manometry and ambulatory pH-impedance monitoring,which allows to discriminate non-erosive reflux disease patients from those presenting esophageal hypersensitivity or functional heartburn.Treatment has been primarily based on doubling the PPI dose or switching to another PPI.Patients with proven disease,not responding to PPI twice daily,are eligible for anti-reflux surgery.

Gastroesophageal reflux disease: Update on inflammation and symptom perception

Although gastroesophageal reflux disease(GERD)is a common disorder in Western countries,with a significant impact on quality of life and healthcare costs,the mechanisms involved in the pathogenesis of symptoms remain to be fully elucidated.GERD symptoms and complications may result from a multifactorial mechanism,in which acid and acid-pepsin are the important noxious factors involved.Prolonged contact of the esophageal mucosa with the refluxed content,probably caused by a defective anti-reflux barrier and luminal clearance mechanisms,would appear to be responsible for macroscopically detectable injury to the esophageal squamous epithelium.Receptors on acid-sensitive nerve endings may play a role in nociception and esophageal sensitivity,as suggested in animal models of chronic acid exposure.Meanwhile,specific cytokine and chemokine profiles would appear to underlie the various esophageal phenotypes of GERD,explaining,in part,the genesis of esophagitis in a subset of patients.Despite these findings,which show a significant production of inflammatory mediators and neurotransmitters in the pathogenesis of GERD,the relationship between the hypersensitivity and esophageal inflammation is not clear.Moreover,the large majority of GERD patients(up to 70%)do not develop esophageal erosions,a variant of the condition called non-erosive reflux disease.This summary aims to explore the inflammatory pathway involved in GERD pathogenesis,to better understand the possible distinction between erosive and non-erosive reflux disease patients and to provide new therapeutic approaches.

Gastro-esophageal reflux disease and obesity, where is the link?

The confluence between the increased prevalence of gastro-esophageal reflux disease(GERD)and of obesity has generated great interest in the association between these two conditions.Several studies have addressed the potential relationship between GERD and obesity,but the exact mechanism by which obesity causes reflux disease still remains to be clearly defined.A commonly suggested pathogenetic pathway is the increased abdominal pressure which relaxes the lower esophageal sphincter,thus exposing the esophageal mucosal to gastric content.Apart from the mechanical pressure,visceral fat is metabolically active and it has been strongly associated with serum levels of adipocytokines including interleukin-6 and tumor necrosis factorα,which may play a role in GERD or consequent carcinogenesis.This summary is aimed to explore the potential mechanisms responsible for the association between GERD and obesity,and to better understand the possible role of weight loss as a therapeutic approach for GERD.

Epigenetic mechanisms in non-alcoholic fatty liver disease:An emerging field

Non-alcoholic fatty liver disease(NAFLD) is an emerging health concern in both developed and non-developed world, encompassing from simple steatosis to nonalcoholic steatohepatitis(NASH), cirrhosis and liver cancer. Incidence and prevalence of this disease are increasing due to the socioeconomic transition and change to harmful diet. Currently, gold standard method in NAFLD diagnosis is liver biopsy, despite complications and lack of accuracy due to sampling error. Further, pathogenesis of NAFLD is not fully understood, but is well-known that obesity, diabetes and metabolic derangements played a major role in disease development and progression. Besides, gut microbioma and host genetic and epigenetic background could explain considerable interindividual variability. Knowledge that epigenetics, heritable events not caused by changes in DNA sequence, contribute to development of diseases has been a revolution in the last few years. Recently, evidences are accumulating revealing the important role of epigenetics in NAFLD pathogenesis and in NASH genesis. Histone modifications, changes in DNA methylation and aberrant profiles or micro RNAs could boost development of NAFLD and transition into clinical relevant status. PNPLA3 genotype GG has been associated with a more progressive disease and epigenetics could modulate this effect. The impact of epigenetic on NAFLD progression could deserve further applications on therapeutic targets together with future non-invasive methods useful for the diagnosis and staging of NAFLD.

Wilson's disease:Revisiting an old friend

Wilson's disease(WD)is a rare condition caused by copper accumulation primarily in the liver and secondly in other organs,such as the central nervous system.It is a hereditary autosomal recessive disease caused by a deficiency in the ATP7B transporter.This protein facilitates the incorporation of copper into ceruloplasmin.More than 800 mutations associated with WD have been described.The onset of the disease frequently includes manifestations related to the liver(as chronic liver disease or acute liver failure)and neurological symptoms,although it can sometimes be asymptomatic.Despite it being more frequent in young people,WD has been described in all life stages.Due to its fatal prognosis,WD should be suspected in all patients with unexplained biochemical liver abnormalities or neurological or psychiatric symptoms.The diagnosis is established with a combination of clinical signs and tests,including the measurement of ceruloplasmin,urinary copper excretion,copper quantification in liver biopsy,or genetic assessment.The pharmacological therapies include chelating drugs,such as D-penicillamine or trientine,and zinc salts,which are able to change the natural history of the disease,increasing the survival of these patients.In some cases of end-stage liver disease or acute liver failure,liver transplantation must be an option to increase survival.In this narrative review,we offer an overview of WD,focusing on the importance of clinical suspicion,the correct diagnosis,and treatment.

Hepatitis C virus genotype 3: Meta-analysis on sustained virologic response rates with currently available treatment options

AIM: To address the therapeutic efficacy of various treatment regimens in genotype 3 selecting randomized clinical trials and prospective National Cohort Studies.METHODS:(1) PEG-INF-based therapy including sofosbuvir(SOF) + RBV for 12 wk vs SOF + RBV 24 wk;(2) SOF + RBV therapy 12 wk/16 wk vs 24 wk; and(3) the role of RBV in SOF + daclatasvir(DCV) and SOF + ledipasvir(LDV) combinations. This metaanalysis provides robust information with the intention of addressing treatment strategy for hepatitis C virus genotype 3.RESULTS: A combination treatment including SOF + RBV + PEG-IFN for 12 wk notes better SVR than with only SOF + RBV for 12 wk, although its association with more frequent adverse effects may be a limiting factor. Longer duration therapy with SOF + RBV(24 wk) has achieved higher SVR rates than shorter durations(12 or 16 wk). SOF + LDV are not an ideal treatment for genotype 3. CONCLUSION: Lastly, SOF + DCV combination is probably the best oral therapy option and the addition of RBV does not appear to be needed to increase SVR rates substantially.

Assessing cardiovascular risk in hepatitis C: An unmet need

Chronic hepatitis C virus(HCV) is associated with significant morbidity and mortality, as a result of the progression towards cirrhosis and hepatocellular carcinoma. Additionally, HCV seems to be an independent risk factor for cardiovascular diseases(CVD) due to its association with insulin resistance, diabetes and steatosis. HCV infection represents an initial step in the chronic inflammatory cascade, showing a direct rolein altering glucose metabolism. After achieving sustained virological response, the incidence of insulin resistance and diabetes dramatically decrease. HCV core protein plays an essential role in promoting insulin resistance and oxidative stress. On the other hand, atherosclerosis is a common disease in which the artery wall thickens due to accumulation of fatty deposits. The main step in the formation of atherosclerotic plaques is the oxidation of low density lipoprotein particles, together with the increased production of proinflammatory markers [tumor necrosis factor-α, interleukin(IL)-6, IL-18 or C-reactive protein]. The advent of new direct acting antiviral therapy has dramatically increased the sustained virological response rates of hepatitis C infection. In this scenario, the cardiovascular risk has emerged and represents a major concern after the eradication of the virus. Consequently, the number of studies evaluating this association is growing. Data derived from these studies have demonstrated the strong link between HCV infection and the atherogenic process, showing a higher risk of coronary heart disease, carotid atherosclerosis, peripheral artery disease and, ultimately, CVD-related mortality.

Eosinophilic esophagitis: New insights in pathogenesis and therapy

Eosinophilic esophagitis(Eo E) is a clinico-pathological entity with esophageal symptoms and dense esophageal eosinophilic infiltration throughout the esophagus that may persist despite treatment with proton pump inhibitors. This eosinophilic infiltration is usually absent in the stomach, small intestine and colon, although there are a number of reports of patients with a multiorgan involvement. EoE is associated with abnormalities involving TH2-dependent immunity, with multiple environmental factors strongly contributing to disease expression. The layer of the esophagus affected by the eosinophilic infiltration causes the specific symptoms. Esophageal involvement results mostly in dysphagia for solids that can be severe enough to cause recurrent esophageal obstruction with typical endoscopic features suggesting esophageal remodeling and pathological changes of eosinophilic infiltration of the mucosa, sub-epithelial fibrosis and muscle hypertrophy. This disease is frequently associated with other allergic conditions such as allergic asthma, allergic dermatitis and eosinophilia. The treatment of patients with Eo E depends on the severity of the symptoms and of the inflammatory process as well as to their response to a gradual step-up treatment. The first line of treatment consists of steroid containing local inhalers. If unresponsive they are then treated with oral steroids. Intravenous interleukin blockers seem to have a consistent positive therapeutic effect.

Glutaminolysis-ammonia-urea Cycle Axis,Non-alcoholic Fatty Liver Disease Progression and Development of Novel Therapies

The prevalence of non-alcoholic fatty liver disease(NAFLD)is increasing worldwide,reflecting the current epidemics of obesity,insulin resistance,type 2 diabetes mellitus,and metabolic syndrome.NAFLD is characterized by the accumulation of fat in the liver,and is known to be a cause of cirrhosis.Although many pathways have been proposed,the cause of NAFLD-linked fibrosis progression is still unclear,which posed challenges for the development of new therapies to prevent NASH-related cirrhosis and hepatocellular carcinoma.Cirrhosis is associated with activation of hepatic stellate cells(HSC)and accumulation of excess extracellular matrix proteins,and inhibiting the activation of HSCs would be expected to slow the progression of NAFLD-cirrhosis.Multiple molecular signals and pathways such as oxidative stress and glutaminolysis have been reported to promote HSC activation.Both mechanisms are plausible antifibrotic targets in NASH,as the activation of HSCs the proliferation of myofibroblasts depend on those processes.This review summarizes the role of the glutaminolysis-ammonia-urea cycle axis in the context of NAFLD progression,and shows how the axis could be a novel therapeutic target.