Human gastric epithelium produces IL-4 and IL-4delta2 isoform only upon Helicobacter pylori infection

Recent evidence suggests that interleukin-4 (IL-4) is related to mucosal tolerance by which an injurious immune response is prevented, suppressed or shifted to a non-injurious response. We investigated the expression of IL-4 and its splice variant isoform IL-4delta2 in gastric epithelial cells of healthy subjects and gastritis patients infected with Helicobacter pylori (H. pylori) with or without the cag pathogenicity island (cag-PAI). IL-4 and IL-4delta2 mRNAs were evaluated in microdissected gastric epithelium and in AGS cell lines co-cultured with H. pylori B128 or SS1 strains. IL-4 mRNA was consistently detected in microdissected gastric epithelial cells from healthy subjects. The IL-4 mRNA expression was low in H. pylori?infected patients, and markedly reduced in cag-PAI-positive ones. IL-4delta2 mRNA was expressed on gastric epithelium of H. pylori-infected patients, but not in healthy subjects. The IL-4delta2 expression was lower in cag-PAI-positive than in cag-PAI-negative H. pylori infected patients. AGS cells also produced IL-4 mRNA upon SS1 strain stimulation, whereas IL-4delta2 mRNA expression was detected in AGS co-cultured with either SS1 or B128 strains. An inverse correlation was documented between IL-4 and IL-4delta2 mRNA expression by microdissected gastric epithelial cells and the score of gastritis. IL-4, but not IL-4delta2, is expressed by gastric epithelium of healthy subjects, whereas IL-4delta2 and lesser IL-4 mRNA are detectable in the gastric epithelium of H. pylori-infected patients. Data suggest that gastric epithelial cells might regulate the balance between tolerance and immune response by the fine tuning of IL-4 and IL-4delta2 expression.

Treatment options in pediatric GERD

Gastroesophageal reflux (GER) is a common physiologic phenomenon in infants and children. GER that results in symptoms or complications--hence the evolution to GER disease (GERD)--warrants targeted evaluation and appropriate treatment. Judicious use of acid-suppression therapy remains the mainstay of pharmacologic treatment of GERD. However, recognition of treatment goals and potentials risks of acid suppression must be considered prior to initiation of therapy. The role of surgical intervention for GERD remains limited.

Upregulation of CCL20 and recruitment of CCR6+ gastric infiltrating lymphocytes in Helicobacter pylori gastritis

Helicobacter pylori infection is associated with an inflammatory response in the gastric mucosa, leading to chronic gastritis, peptic ulcers, and gastric cancer. There is increased T-cell infiltration at the site of infection with H. pylori. CCR6, a specific beta-chemokine receptor for CCL20 (MIP-3alpha/LARC/exodus), has recently been reported to mediate lymphocyte homeostasis and immune responses in mucosal tissue, and it may play a role in chemokine-mediated lymphocyte trafficking during gastric inflammation. In this study, we investigated the role of CCR6 and its ligand, CCL20, in inducing an inflammatory response in the gastric mucosa during H. pylori infection. Gastric infiltrating T lymphocytes were isolated from endoscopic biopsy specimens of H. pylori gastritis patients and analyzed for the expression of the CCR6 chemokine receptor. Our results demonstrated that there was significantly increased CCR6 expression in CD3(+) T cells infiltrating the gastric mucosa, and the CCR6 ligand, the CCL20 chemokine, was selectively expressed in inflamed gastric tissues. The production of CCL20 was upregulated in response to H. pylori in gastric epithelial cells when there was stimulation by the proinflammatory cytokines interleukin-1beta and tumor necrosis factor alpha. Furthermore, recombinant CCL20 induced lymphocyte chemotaxis migration in fresh gastric T cells ex vivo, indicating that the gastric T cells could migrate toward inflammatory sites via CCR6/CCL20 interaction. Our results suggest that the interaction between CCL20 and CCR6 may play a role in chemokine-mediated lymphocyte trafficking during gastric inflammation in Helicobacter infection.

Oral tacrolimus for steroid-dependent and steroid-resistant ulcerative colitis in children

PURPOSE

To evaluate tacrolimus in 3 situations: for the induction of remission in children with severe steroid-resistant ulcerative colitis (UC); for steroid sparing in children with steroid-dependent UC in whom treatment with other immunosuppressants fails; and for the maintenance of remission in children with steroid-dependent and steroid-resistant UC.

PATIENTS AND METHODS

We retrospectively evaluated 18 consecutive patients (13 with pancolitis) who were treated with oral tacrolimus at our institution from May 1999 to October 2005. Nine patients had steroid-resistant UC and 9 patients were steroid-dependent. We started patients initially on tacrolimus 0.2 mg/kg divided twice daily, with a goal plasma trough level of 10 to 15 ng/mL for the first 2 weeks, and then titrated doses to achieve plasma levels between 7 and 12 ng/mL after induction.

RESULTS

Of the 18 patients in this study, 17 showed a positive response to tacrolimus therapy (ie, cessation of diarrhea and other symptoms) and 5 showed a prolonged response to tacrolimus. The mean time from initiation of tacrolimus therapy until response was 8.5 days. The mean duration of response was 260 days. Eleven of 18 patients required colectomy, including all of the patients with steroid-resistant UC, but only 2 of 9 who were steroid-dependent. The mean time from initiation of tacrolimus until colectomy was 392 days.

CONCLUSIONS

It is possible that tacrolimus may benefit selected patients with steroid-dependent UC, including those who are intolerant of 6-mercaptopurine or azathioprine. Conversely, patients with steroid-resistant UC are unlikely to sustain a prolonged clinical response to tacrolimus and seem to require colectomy eventually. Careful considerations of risk versus benefit, as well as close monitoring for adverse effects, are essential in all patients.

Detection of gastric pepsin in middle ear fluid of children with otitis media

OBJECTIVE

We sought to confirm the finding of pepsin/pepsinogen in the middle ear fluid of children with otitis media in a larger sample size using a sensitive and specific pepsin assay.

STUDY DESIGN AND SETTING

We evaluated 152 children (225 ear samples) in a prospective study at a tertiary care children's hospital. The presence of pepsin in middle ear aspirates was determined using enzymatic assay.

RESULTS

Of the patients, 14.4 percent (22 of 152) had detectable pepsin activity in one or both of the ear samples with no pepsin activity detected in control serum. Average pepsin concentration in the samples was 96.6 +/- 170.8 ng/ml, ranging from 13 to 687 ng/ml. Pepsin concentration in the middle ear of children younger than 1.0 year was significantly higher than in older age groups.

CONCLUSION AND SIGNIFICANCE

Results indicate that pepsin/pepsinogen is present in the middle ears of children with otitis media, although not at the high rate previously reported. Gastric reflux may be one causative factor in the pathogenesis of otitis media.

Surgical management of Crohn's colitis

Crohn's disease in childhood is changing. The incidence is increasing, colonic disease is becoming more prevalent in younger children, and colon reconstruction is more acceptable. Genetic phenotypes are influencing decisions for surgery, and targeted immunotherapy has renewed hope for more durable remissions following less extensive resections. The tasks facing the surgeon evaluating a child with Crohn's colitis include confirming the specific diagnostic subtype and selecting the correct procedure. This chapter will review the unique aspects of pediatric Crohn's colitis and the increased complexity of surgical choice for this most challenging presentation. Recent success with less extensive surgery offers renewed hope for children with intractable colonic disease.

Combination of Helicobacter pylori strain and tumor necrosis factor-alpha polymorphism of the host increases the risk of peptic ulcer disease in children

BACKGROUND

Helicobacter pylori infection is probably acquired in childhood and causes a vigorous immune response. It is unclear why only a subgroup of infected children develops peptic ulcer disease. We have previously reported that iceA1 strains tend to be associated with duodenal disease in children. However, the pathogenesis probably does not depend solely on the H pylori strain but also on the variability of the host response.

OBJECTIVES

The aim of this study was to assess the significance of tumor necrosis factor-alpha (TNF-alpha) promoter polymorphism in relation to infection with H pylori strains in children.

METHODS

A total of 113 antral biopsies of H pylori-positive children (ages 2-18 years) were analyzed. Of these, 23 had duodenal disease, including erosive duodenitis and/or duodenal ulceration, and 90 had gastritis only. H pylori infection was diagnosed by bacterial culture and histology. Patient genomic DNA extracted from the antral biopsy was used to characterize the genetic polymorphism of TNF-alpha promoter at nucleotide positions -308 and -238 by polymerase chain reaction-based restriction fragment-length polymorphism. All H pylori strains were examined for cytotoxin-associated gene A and induced-by-contact-with-epithelium gene (iceA1).

RESULTS

A total of 31% of children with duodenal disease were infected with iceA1 positive strains and had the -238 G to A polymorphism in the TNF-alpha gene vs only 1.6% of children with gastritis alone (P < 0.0005).

CONCLUSIONS

The combination of bacterial iceA1 and TNF-alpha 238 G to A polymorphism may be a risk factor for peptic ulcer disease in children infected with H pylori. Larger studies are needed to confirm this association.

The Crystal Structure of the Human (S100A8/S100A9)2 Heterotetramer, Calprotectin, Illustrates how Conformational Changes of Interacting α-Helices Can Determine Specific Association of Two EF-hand Proteins

The EF-hand proteins S100A8 and S100A9 are important calcium signalling proteins that are involved in wound healing and provide clinically relevant markers of inflammatory processes, such as rheumatoid arthritis and inflammatory bowel disease. Both can form homodimers via distinct modes of association, probably of lesser stability in the case of S100A9, whereas in the presence of calcium S100A8 and S100A9 associate to calprotectin, the physiologically active heterooligomer. Here we describe the crystal structure of the (S100A8/S100A9)(2) heterotetramer at 1.8 A resolution. Its quaternary structure illustrates how specific heteroassociation is energetically driven by a more extensive burial of solvent accessible surface areas in both proteins, most pronounced for S100A9, thus leading to a dimer of heterodimers. A major contribution to tetramer association is made by the canonical calcium binding loops in the C-terminal halves of the two proteins. The mode of heterodimerisation in calprotectin more closely resembles the subunit association previously observed in the S100A8 homodimer and provides trans stabilisation for S100A9, which manifests itself in a significantly elongated C-terminal alpha-helix in the latter. As a consequence, two different putative zinc binding sites emerge at the S100A8/S100A9 subunit interface. One of these corresponds to a high affinity arrangement of three His residues and one Asp side-chain, which is unique to the heterotetramer. This structural feature explains the well known Zn(2+) binding activity of calprotectin, whose overexpression can cause strong dysregulation of zinc homeostasis with severe clinical symptoms.

Prevalence of Helicobacter pylori vacA, cagA, cagE, iceA and babA2 genotypes in Thai dyspeptic patients

OBJECTIVES

To investigate the prevalence of the vacA, cagA, cagE, iceA, and babA2 genotypes in Helicobacter pylori strains isolated from Thai dyspeptic patients, and to determine whether any correlation exists between these genotypes and clinical manifestations.

METHODS

Helicobacter pylori was examined in 112 patients (62 with non-ulcer dyspepsia (gastritis), 34 with peptic ulcer disease, and 16 with gastric cancer (GCA)), detected by culture or direct detection from gastric biopsies. Allelic variants of the vacA, cagA, cagE, iceA, and babA2 genotypes were identified by using the polymerase chain reaction.

RESULTS

The positive rates for the vacAs1, vacAs2, cagA, cagE, iceA1, iceA2, and babA2 genes in H. pylori of dyspeptic patients were 100%, 0%, 98.2%, 88.4%, 45.5%, 33.1%, and 92%, respectively. The allelic variant vacAs1m1 was more prevalent (58%) than vacAs1m2 (42%). The cagA and cagE genes were commonly found together (87.5%). The most predominant genotypes were vacAs1m1, cagA, cagE, iceA1, and babA2. The various genes alone or in combination had no statistically significant association with the clinical outcomes (p>0.05).

CONCLUSION

Neither single gene nor combination of vacA, cagA, cagE, iceA, and babA2 genes was significantly helpful in predicting the clinical outcome of H. pylori infection in Thai patients. The high prevalence of these genes in H. pylori isolated from Thai patient groups suggests that H. pylori strains are geographically dependent.

Genes, diet and inflammatory bowel disease

Inflammatory bowel disease (IBD) arises in part from a genetic predisposition, through the inheritance of a number of contributory genetic polymorphisms. These variant forms of genes may be associated with an abnormal response to normal luminal bacteria. A consistent observation across most populations is that any of three polymorphisms of the Caspase-activated recruitment domain (CARD15) gene are more prevalent in IBD patients as compared with unaffected controls. Similar aberrant responses to bacteria are associated with variants in Autophagy-related 16-like 1 (ATG16L1) and human defensin (HBD-2, -3 and -4) genes. The defective bacterial signal in turn leads to an excessive immune response, presenting as chronic gut inflammation in susceptible individuals. Inconsistent population reports implicate the major histocompatability complex (MHC), that encodes a number of human leukocyte antigens (HLA), MHC class I chain-related gene A (MICA) or cytokines, such as tumour necrosis factor-alpha (TNF-alpha). Toll-like receptors encoded by the TLR4 or TLR9 genes may also play a role. Recent whole genome scans suggest that a rare variant in the interleukin-23 receptor (IL23R) gene may actually protect against IBD. Other implicated genes may affect mucosal cell polarity (Drosophila discs large homologue 5, DLG5) or mucosal transporter function (sodium dependent organic cation transporters, SLC22A4 and SLC22A5). A variant in ABCB1 (ATP-binding cassette subfamily B member 1) may be especially associated with increased risk of UC. While pharmacogenetics is increasingly being used to predict and optimise clinical response to therapy, nutrigenetics may have even greater potential. In many cases, IBD can be controlled through prescribing an elemental diet, which appears to act through modulating cytokine response and changing the gut microbiota. More generally, no single group of dietary items is beneficial or detrimental to all patients, and elimination diets have been used to individualise dietary requirements. However, recognising the nature of the genes involved may suggest a more strategic approach. Pro- or prebiotics will directly influence the microbial flora, while immunonutrition, including omega-3 fatty acids and certain polyphenols, may reduce the symptoms of gut inflammation. The expression of gut transporters may be modulated through various herbal remedies including green tea polyphenols. Such approaches would require that the gene of interest is functioning normally, other than its expression being up or down-regulated. However, new approaches are being developed to overcome the effects of polymorphisms that affect the function of a gene. A combination of human correlation studies with experimental models could provide a rational strategy for optimising nutrigenetic approaches to IBD.

Immune and proliferative cellular responses to Helicobacter pylori infection in the gastric mucosa of Mexican children

BACKGROUND

Helicobacter pylori infection occurs mostly during childhood, but few studies on this age group have addressed the innate immune and the proliferative response to this infection. Mexico has a high H. pylori prevalence in children, but a low risk of gastric cancer. The aim of this work was to study the cellular responses of the gastric mucosa to this infection in Mexican children.

METHODS

Antral and corpus gastric biopsies were obtained from 44 H. pylori-infected children (mean age 12 +/- 3.2 years) and 44 uninfected children (mean age 10 +/- 3 years). Mucosal cellular responses were studied by immunohistochemistry, using anti-Ki67 antibodies for proliferation studies, antihuman tryptase for mast cells, and antihuman CD68 for macrophages. T and B lymphocytes were stained with a commercial integrated system. The intensity of cellular responses was estimated histologically using the software KS300.

RESULTS

Epithelium proliferation and infiltration of macrophages and T and B lymphocytes were significantly higher in H. pylori-infected than in uninfected children. A balanced increase of CD4, CD8, and CD20 lymphocytes was observed in infected children. However, activated mast cells were decreased, and infiltration of neutrophil and mononuclear cells was low. Epithelial proliferation was associated with polymorphonuclear infiltration but not with infiltration of macrophages or lymphocytes. Inflammation and proliferation was higher in CagA (+)-infected children.

CONCLUSIONS

Mexican children respond to H. pylori infection with a low inflammatory response, a balanced increase of T and B lymphocytes, and a high regenerative activity.

Severe systemic adverse reaction to proton pump inhibitors in an infant

Episodes of respiratory distress with chest retraction and wheezing, sometimes associated with facial edema, were noted after administering the proton pump inhibitors omeprazole and esomeprazole in an infant with gastroesophageal reflux. The disturbances relieved dramatically after withdrawing the proton pump inhibitor.

Inflammatory bowel disease in the pediatric patient

Inflammatory bowel disease (IBD) is a general term used to describe two chronic bowel disorders, Crohn's disease (CD) and ulcerative colitis (UC), both of which are characterized by autoimmune-related inflammation of the intestines. UC is limited to the colonic mucosa, whereas CD can involve any part of the intestinal tract from the mouth to the anus. The true etiology of UC and CD is still unknown, although extensive research has identified some genetic and environmental factors. This article discusses current clinical concepts of both diseases in the pediatric population.

CXCL5 overexpression is associated with late stage gastric cancer

PURPOSE

Chemokines play multiple roles in the development and progression of many different tumors. Our cDNA array data suggested that chemokine CXCL5 was upregulated in gastric cancer. Here, we analyzed CXCL5 protein expression in gastric cancer and investigated the clinical implications of CXCL5 upregulation.

METHODS

Immunostaining for CXCL5 was performed on gastric tissue microarrays of tissue specimens obtained by gastrectomy. The intensity of immunostaining in tumor tissue was considered strong when tumor tissue staining was more intense than in normal tissue; the intensity was null when staining was weaker in the tumor than in normal tissue; and the intensity was weak when staining was similar in both tissues. Serum CXCL5 levels and microvascular density in tumor tissue were measured by ELISA and monoclonal antibody to Factor VIII.

RESULTS

Strong CXCL5 expression correlated with tumor stage. CXCL5 expression did not correlate with T stage. However, N stage positively correlated with CXCL5 expression. Serum CXCL5 levels in late stage (IIIB, IV) gastric cancer patients were higher than in patients with benign conditions. Microvascular density was higher in tumors with strong CXCL5 expression, but the correlation with CXCL5 was not linear. Multiple logistic regression analyses showed that, compared to no or weak expression, strong expression of CXCL5 was a significant risk factor for high N stage (N2, N3).

CONCLUSIONS

CXCL5 overexpression was associated with late stage gastric cancer and high N stage. These results suggest a role for CXCL5 in the progression of gastric cancer, specifically in lymph node metastasis.

Quality of life in paediatric gastrointestinal and liver disease: a systematic review

OBJECTIVES

To identify and appraise all studies relating to and instruments developed to measure quality of life (QOL) in children with gastrointestinal or liver diseases.

METHODS

A literature search was undertaken using MEDLINE, EMBASE, CINAHL, and PsycINFO to identify relevant articles published up to the end of 2005. These were reviewed by both authors and data were extracted using a standardised form. Articles were excluded if no attempt was made to measure QOL, they did not relate to children ages <17 years, they did not relate to gastrointestinal or liver diseases, or they were review articles. Quality of life instruments identified were rated according to proposed criteria.

RESULTS

From a total of 2379 articles identified in the initial search, a total of 2309 were excluded, leaving 70 included studies. These were assigned to the following categories: inflammatory bowel disease, n = 17; cystic fibrosis, n = 20; liver disease, n = 11; surgery, n = 15; and miscellaneous, n = 7. These studies describe the impact that these diseases have on the QOL of affected children. A total of 11 disease-specific QOL instruments and 1 generic instrument with a chronic disease module were identified, but only 5 of these fulfilled the proposed quality criteria and can be recommended for future use.

CONCLUSIONS

Chronic gastrointestinal and liver diseases can have an enormous effect on the QOL of affected individuals and their families. A number of disease-specific paediatric QOL instruments have been developed and validated. Quality of life is an important outcome that should be incorporated into clinical practice and measured when treatments are evaluated. Future research should explore how QOL can best be improved in children in whom it is severely impaired.

Probiotics in paediatric gastrointestinal diseases

Probiotics have become increasingly popular and are now promoted as having a wide range of benefits. Probiotics are generally very well tolerated and safe but many of the purported uses are not yet well supported with adequate scientific evidence. Two well-established roles for probiotics in children are acute diarrhoeal illness and antibiotic-associated diarrhoea. This review summarises the evidence supporting probiotics for various gastrointestinal disorders with particular reference to their role in the management of acute diarrhoea and antibiotic-associated diarrhoea in children.

Pepsin assay: a marker for reflux in pediatric glue ear

OBJECTIVE

To evaluate if analysis of pepsin/pepsinogen in middle ear effusions can be considered a diagnostic marker for laryngopharyngeal reflux (LPR) in children with otitis media with effusion (OME).

MATERIAL AND METHODS

Ambulatory 24-hour dual-probe pH monitoring was carried out on 31 children with OME. Middle ear effusions were collected from 17 children during myringotomy. Total pepsin/pepsinogen concentrations in effusions were measured by ELISA using antipepsin antibody.

RESULTS

Dual-probe pH monitoring showed that 22/31 (71%) of the studied children had significant LPR. The concentrations of pepsin/pepsinogen in middle ear effusions, ranged from 0.085 to 5.02 microg/ml, were found to be up to 4.5 to 231.44 times higher than the serum levels. There was a significant positive correlation between the level of pepsin/pepsinogen assayed in the effusions of the 17 children and the number of pharyngeal reflux episodes measured by pH monitoring.

CONCLUSIONS

Control of LPR may be an essential component in the successful management of OME in pediatric patients. Pepsin/pepsinogen analysis in effusions of children, using ELISA, can be considered a reliable marker for assessment of reflux in children with OME.

Rectal bleeding in children: endoscopic evaluation revisited

OBJECTIVES

Rectal bleeding is an alarming event both for the child and parents. It is hypothesized that colonoscopy instead of sigmoidoscopy and adding esophago-gastro-duodenoscopy in case of accompanying complaints, improves the diagnostic accuracy in children with prolonged rectal bleeding.

STUDY DESIGN

All pediatric patients undergoing colonoscopy because of prolonged rectal bleeding over an 8-year period at the Emma Children's Hospital/Academic Medical Centre were reviewed. Patient demographics, clinical features, number and extent of endoscopic examinations and the endoscopic and histopathological findings were assessed.

RESULTS

A total of 147 colonoscopies were performed in 137 pediatric patients (63 boys) because of prolonged rectal bleeding. Inflammatory bowel disease and polyp(s) were the most prevalent diagnoses. In 72% of patients diagnosed as Crohn's disease, focal, chronically active gastritis was seen on histology, giving support to the diagnosis Crohn's disease. In 22% of the cases polyps would have been missed in the case where only sigmoidoscopy was performed. No complications after endoscopic intervention were seen.

CONCLUSIONS

Colonoscopy is the investigation of choice in children with prolonged rectal bleeding. In patients presenting with accompanying complaints such as abdominal pain or diarrhea, it is advisable to perform ileocolonoscopy combined with esophago-gastro-duodenoscopy. This combines a high diagnostic yield with a safe procedure.

The current status of Helicobacter pylori vaccines: a review

Helicobacter pylori, a Gram-negative flagellate bacterium that infects the stomach of more than half of the global population, is regarded as the leading cause of chronic gastritis, peptic ulcer disease, and even gastric adenocarcinoma in some individuals. Although the bacterium induces strong humoral and cellular immune responses, it can persist in the host for decades. It has several virulence factors, some of them having vaccine potential as judged by immunoproteomic analysis. A few vaccination studies involving a small number of infected or uninfected humans with various H. pylori formulations such as the recombinant urease, killed whole cells, and live Salmonella vectors presenting the subunit antigens have not provided satisfactory results. One trial that used the recombinant H. pylori urease coadministered with native Escherichia coli enterotoxin (LT) demonstrated a reduction of H. pylori load in infected participants. Although extensive studies in the mouse model have demonstrated the feasibility of both therapeutic and prophylactic immunizations, the mechanism of vaccine-induced protection is poorly understood as several factors such as immunoglobulin and various cytokines do not contribute to protection. Transcriptome analyses in mice have indicated the role of nonclassical immune factors in vaccine-induced protection. The role of regulatory T cells in the persistence of H. pylori infection has also been suggested. A recently developed experimental H. pylori infection model in humans may be used for testing several new adjuvants and vaccine delivery systems that have been currently obtained. The use of vaccines with appropriate immunogens, routes of immunization, and adjuvants along with a better understanding of the mechanism of immune protection may provide more favorable results.

Helicobacter pylori detection and antimicrobial susceptibility testing

The discovery of Helicobacter pylori in 1982 was the starting point of a revolution concerning the concepts and management of gastroduodenal diseases. It is now well accepted that the most common stomach disease, peptic ulcer disease, is an infectious disease, and all consensus conferences agree that the causative agent, H. pylori, must be treated with antibiotics. Furthermore, the concept emerged that this bacterium could be the trigger of various malignant diseases of the stomach, and it is now a model for chronic bacterial infections causing cancer. Most of the many different techniques involved in diagnosis of H. pylori infection are performed in clinical microbiology laboratories. The aim of this article is to review the current status of these methods and their application, highlighting the important progress which has been made in the past decade. Both invasive and noninvasive techniques will be reviewed.

The association between clinical pathways and hospital length of stay: a case study

Clinical pathways are the treatment protocol in order to reduce or eliminate variation of care by specifying to nursing and medical staff. The effectiveness of the clinical pathways to accomplish this goal, however, is in question. With the implementation of the clinical pathways in 2001, this study evaluates the effectiveness of clinical pathway in reducing the inpatient length of stay in a rural hospital in a Midwestern state. All inpatient cases were used with the primary diagnoses of chronic obstructive pulmonary disease, congestive heart failure, diabetes, myocardial infarction, and pneumonia from the years of 1999-2003. By controlling for gender, age, insurance type, and year, this study employs a multiple regression analysis to evaluate the association between clinical pathways and the length of stay. Only one (the clinical pathway for myocardial infarction) out of the five pathways studied showed an association with a statistical significance in decreasing the length of stay. Health care administrators should consider other aspects as well as the hospital length of stays when implementing clinical pathways in their facility.

Wolinella succinogenes response to ox-bile stress

The bacterium Wolinella succinogenes is the only known species of its genus. It was first isolated from cow ruminal fluid, and in cattle, it dwells in the reticulum and rumen compartments of the stomach. The global protein response of W. succinogenes to ox-bile was investigated with the aim to understand bile-tolerance mechanisms of the bacterium. Bacteria were grown in liquid media supplemented with different bile concentrations to determine its effects on growth and morphology. Proteomic analyses served to identify 14 proteins whose expression was modulated by the presence of 0.2% bile. Quantitative real-time PCR analyses of the expression of selected genes were employed to obtain independent confirmation of the proteomics data. Proteins differentially expressed revealed metabolic pathways involved in the adaptation of W. succinogenes to bile. The data suggested that bile stress elicited complex physiological responses rather than just specific pathways, and identified proteins previously unknown to be involved in the adaptation of bacteria to bile.

Effects of Helicobacter hepaticus on the proteome of HEp-2 cells

Helicobacter hepaticus infects the bowel and biliary tree of several animals, producing inflammation. Colonisation of mouse livers can induce hepatocellular carcinomas. The effects of H. hepaticus on the proliferation and global protein expression of human HEp-2 cells were studied by examining the changes in the protein profiles of cells exposed to the bacterium. HEp-2 cells were grown for four days under a microaerobic atmosphere or under the same conditions in co-cultures with H. hepaticus at various inoculum densities. Enlargement, distension and elongation of HEp-2 cells were observed in co-cultures with H. hepaticus. The number of live cells declined by only an order of magnitude at bacterial inocula of approximately 10(9)cfu/ml, but were reduced to less than 10(3)cells/ml at approximately 10(10)cfu/ml bacteria inocula. Protein expression by HEp-2 cells was investigated employing two-dimensional gel electrophoresis. In cells grown with or without bacteria, 17 differentially expressed proteins were identified by tandem mass spectrometry. These proteins participated in several biological functions including amino acid metabolism, cell growth and proliferation, stress response, protein translation and modification, etc. The onset of a catastrophic killing of HEp-2 cells at a bacterial density of approximately 10(9)cfu/ml suggested a multimodal action for H. hepaticus infection, and the modulation of the expression of proteins involved in different biological functions showed that the presence of H. hepaticus has broad effects on the physiology of HEp-2 cells.

Enzymes in feces: useful markers of chronic inflammatory bowel disease

BACKGROUND

Ulcerative colitis and Crohn's disease are characterized by a chronic intestinal inflammation. Since the precise etiology is still unknown, current therapies are aimed at reducing or eliminating inflammation.

METHODS

Endoscopy and histology on biopsy specimens remain the gold standard methods for detecting and quantifying bowel inflammation. These technique are expensive, invasive and not well tolerated by patients since the need of repeated examinations affects their quality of life. Although disease activity scores and laboratory inflammatory markers are widely used they showed unreliable relations with endoscopy and histology. Fecal markers have been investigated in inflammatory bowel disease (IBD) by many authors for diagnostic purposes, to assess disease activity and of risk of complications, to predict relapse or recurrence, and to monitor the effect of therapy. Many inflammatory mediators have been detected in the feces such as leukocytes, cytokines and proteins from neutrophil activation. Some of these, particularly lactoferrin and calprotectin, have been demonstrated to be useful in detecting active inflammatory bowel disease, in predicting recurrence of disease after surgery or monitoring the effects of medical therapy. Calprotectin and lactoferrin are remarkably stable and easily detect in stool using ELISA so they appear to be equally recommendable as inflammation markers in the lower gastrointestinal tract especially in IBD patients.

CONCLUSION

Fecal markers are non-invasive, simple, cheap, sensitive and specific parameters and are useful to detect strointestinal inflammation.

Adherence and invasion of mouse-adapted H pylori in different epithelial cell lines

AIM: To assess the adhesion and invasion abilities of different mouse adapted H pylori strains in different cell lines in vitro and investigate their effects on the virulence factors cagA and vacA.

METHODS: The adherence and invasion abilities of different H pylori strains in different epithelial cell lines were examined by the gentamycin protection assay. The null mutants of cagA and vacA were processed by direct PCR mutation method. The morphologic changes of different cell lines after H pylori attachment were examined by microscopy.

RESULTS: The densities of adherence to and invasion into cells in vitro were different from those in the mouse infection experiments. 88-3887 strain could invade and adhere to cells stronger than SS1 and X47. All tested strains had better adhering and invasive abilities in SCG-7901 cell. CagA and vacA minus mutants had the same invasion and adherent abilities as their wild types. In all strains and cell lines tested, only AGS cell had the significant hummingbird phenotype after inoculation with the 88-3887 wild-type.

CONCLUSION: Both the host cells and the bacteria play important parts in the invasion and adhesion abilities of H pylori. CagA and VacA are not related to the ability of invasion and adhesion of H pylori in different cell lines in vitro.

Helicobacter pylori-induced apoptosis in T cells is mediated by the mitochondrial pathway independent of death receptors

BACKGROUND

Chronic infection with Helicobacter pylori is related to the pathogenesis of the noncardia carcinoma of the stomach. In this study we investigated the mechanisms of H. pylori-induced apoptosis in T lymphocytes, which could explain a mechanism of immune evasion facilitating chronic inflammation of the mucosa and gastric carcinogenesis.

MATERIALS AND METHODS

The supernatant of H. pylori culture was used to study the mechanism of apoptosis induction in human leukaemia T cell lines Jurkat and CEM and in primary T cells. The cytotoxin associated gene A (CagA) and vacuolating cytotoxin A (Vac A) positive bacterial strain H. pylori 60190 (CagA(+), VacA(+)) and as a control the less toxic H. pylori strain Tx30a (CagA(-), VacA(-)) were used to produce the supernatant. Cell death was determined by DNA fragmentation and protein expression by Western blot.

RESULTS

H. pylori 60190-induced apoptosis was neither blocked by inhibition of the death ligands TRAIL (TNF-related apoptosis-inducing ligand), CD95L/FasL and TNF-alpha (tumour necrosis factor-a) in wild type Jurkat cells nor in FADD(def) (Fas-associated death domain protein) and caspase-8(def) subclones of the Jurkat cell line. Yet, the pancaspase inhibitor zVAD-fmk could inhibit up to 90% of H. pylori-induced apoptosis. Stable transfection of Jurkat wild type cells with Bcl-x(L and) Bcl-2 resulted in marked reduction of H. pylori-induced apoptosis, showing that the mitochondrial pathway is the key regulator. This is supported by the finding that surviving primary human lymphocytes upregulate Bcl-2 when exposed to H. pylori supernatant.

CONCLUSIONS

H. pylori-induced apoptosis of T cells is mediated by the mitochondrial pathway and could create a local environment that facilitates life-long infection by immune evasion.

Current therapy of inflammatory bowel disease in children

Ulcerative colitis (UC) and Crohn disease (CD) are chronic intestinal inflammatory diseases that can present as bloody diarrhea, abdominal pain, and malnutrition. Collectively, these disorders are referred to as inflammatory bowel disease (IBD). All patients with IBD share a common pathophysiology. However, there are a number of developmental, psychosocial, and physiologic issues that are unique to the approximate, equals 20% of patients that present during childhood or adolescence. These include the possibility of disease-induced delays in linear growth or physical development, differences in drug dosing, and the changes in social and cognitive development that occur as children move from school-age years into adolescence and early adulthood. Gastroenterologists caring for these children must therefore develop an optimal regimen of pharmacologic therapies, nutritional management, psychologic support, and properly timed surgery (when necessary) that will maintain disease remission, minimize disease and drug-induced adverse effects, and optimize growth and development. This article reviews current approaches to the management of patients with UC and CD and highlights issues specific to the treatment of children with IBD. The principal medical therapies used to induce disease remission in patients with UC are aminosalicylates (for mild disease), corticosteroids (for moderate disease), and cyclosporine (ciclosporin) (for severe disease). If a patient responds to the induction regimen, maintenance therapies that are used to prevent disease relapse include aminosalicylates, mercaptopurine, and azathioprine. Colectomy with creation of an ileal pouch anal anastomosis (J pouch) has become the standard of care for patients with severe or refractory colitis and results in an improved quality of life in most patients. Therefore, the risks associated with using increasingly potent immunosuppressant agents must be balanced in each case against a patient's desire to retain their colon and avoid a temporary or potentially permanent ileostomy. Decisions about drug therapy in the management of patients with CD are more complex and depend on both the location (e.g. gastroduodenal vs small intestinal vs colonic), as well as the behavior of the disease (inflammatory/mucosal vs stricturing vs perforating) in a given patient. Induction therapies for CD typically include aminosalicylates and antibiotics (for mild mucosal disease), nutritional therapy (including elemental or polymeric formulas), corticosteroids (for moderate disease), and infliximab (for corticosteroid-resistant or fistulizing disease). Aminosalicylates, mercaptopurine, azathioprine, methotrexate, and infliximab can be used as maintenance therapies. Because surgical treatment of CD is not curative, it is typically reserved for those patients either with persistent symptoms and disease limited to a small section of the intestine (e.g. the terminal ileum and cecum) or for the management of complications of the disease including stricture or abdominal abscess. When surgery is necessary, maintenance medications administered postoperatively will postpone recurrence. Patients with UC and CD are at risk for the development of micronutrient deficiencies (including folate, iron, and vitamin D deficiencies) and require close nutritional monitoring. In addition, patients with UC and CD involving the colon are at increased risk of developing colon cancer, and should be enrolled into a colonoscopy surveillance program after 8-10 years of disease duration.

Pouch outcomes among children with ulcerative colitis treated with calcineurin inhibitors before ileal pouch anal anastomosis surgery

PURPOSE

The purpose of this article is to describe the outcomes of the pouches of 14 children with ulcerative colitis (UC) who were pretreated with calcineurin inhibitors before they underwent their ileal pouch anal anastomosis (IPAA) surgery.

METHODS

An institutional review board-approved retrospective review of the charts of consecutive patients with UC treated with calcineurin inhibitors before undergoing IPAA surgery at a tertiary pediatric center between 1998 and 2003 was performed. The primary endpoint was pouch outcome after at least 2 years of follow-up (healthy pouch, acute pouchitis, chronic refractory pouchitis, or pouch failure); the secondary endpoints were early postoperative complications, number of stages, and time between stages.

RESULTS

Fourteen of 53 consecutive patients who underwent IPAA for UC were treated with calcineurin inhibitors before their surgery (26%; 6 with cyclosporine and 8 with tacrolimus). All 14 patients were concomitantly treated with systemic steroids. Ten patients (71%) were also taking 6-mercaptopurine or azathioprine, and 9 (64%) were also taking mesalamine. Three patients (21%) had healthy pouches with no clinical evidence of pouchitis, 6 (43%) had at least one episode of acute pouchitis (average of 2 episodes per year), 3 (21%) had chronic relapsing pouchitis, and 2 (14%) were later determined to have Crohn's disease. There was no pouch failure. Two patients (14%) had an early postoperative complication (intraabdominal abscess, anastomotic stricture). Five patients (36%) had a 2-staged procedure, and 8 (64%) had a 3-staged procedure. For the 2-staged procedures, the mean time between the first and second stages was 3.14 months (range, 3-4 months). For the 3-staged procedures, the mean time between the first and second stages was 4.25 months (range, 2-6 months) and that between the second and third stages was 4 months (range, 2.5-6 months).

CONCLUSIONS

In this series, chronic pouchitis was an infrequent complication among children who were pretreated with calcineurin inhibitors. Calcineurin inhibitor use did not lead to or portend increased early postoperative complications or affect the number or duration of surgical stages. Further studies are required to determine if preoperative calcineurin inhibitors improve pouch outcomes or facilitate the performance of 2-staged procedures.

Homeopathy for childhood and adolescence ailments: systematic review of randomized clinical trials

OBJECTIVE

To assess the evidence of any type of therapeutic or preventive intervention testing homeopathy for childhood and adolescence ailments.

METHODS

Systematic literature searches were conducted through January 2006 in MEDLINE, EMBASE, AMED, CINAHL, Cochrane Central, British Homeopathic Library, ClinicalTrials.gov, and the UK National Research Register. Bibliographies were checked for further relevant publications. Studies were selected according to predefined inclusion and exclusion criteria. All double-blind, placebo-controlled randomized clinical trials of any homeopathic intervention for preventing or treating childhood and adolescence ailments were included. According to the classification of the World Health Organization, the age range defined for inclusion was 0 to 19 years. Study selection, data extraction, and assessment of methodological quality were performed independently by 2 reviewers.

RESULTS

A total of 326 articles were identified, 91 of which were retrieved for detailed evaluation. Sixteen trials that assessed 9 different conditions were included in the study. With the exception of attention-deficit/hyperactivity disorder and acute childhood diarrhea (each tested in 3 trials), no condition was assessed in more than 2 double-blind randomized clinical trials. The evidence for attention-deficit/hyperactivity disorder and acute childhood diarrhea is mixed, showing both positive and negative results for their respective main outcome measures. For adenoid vegetation, asthma, and upper respiratory tract infection each, 2 trials are available that suggest no difference compared with placebo. For 4 conditions, only single trials are available.

CONCLUSION

The evidence from rigorous clinical trials of any type of therapeutic or preventive intervention testing homeopathy for childhood and adolescence ailments is not convincing enough for recommendations in any condition.

Diagnosis of gastro-oesophageal reflux in preterm infants: sonography vs. pH-monitoring

OBJECTIVES

To compare the ultrasound examination with pH-metry in order to evaluate the diagnostic accuracy of sonography for diagnosis of gastro-oesophageal reflux (GOR) in preterm infants.

METHODS

A prospective study was conducted on 31 premature infants <34 weeks with clinically diagnosed GOR. First, they underwent 24-hour pH-monitoring; successively, the sonographic assessment was performed within 12 h after pH-monitoring. The two operators who performed the pH-monitoring and sonography respectively, were unaware of each other's results.

RESULTS

Twenty-one patients (67.7%) had significant GOR with a reflux index >5 (GOR group). The median (range) reflux index in this group was 9.19% (6.04-20.1). Ten newborns (32.3%) did not have significant GOR with a reflux index <5. Sonography was positive for GOR in 8 patients (25.8%); all 8 infants with sonographic diagnosis of GOR had a reflux index >5. Therefore, sonographic diagnosis did not produce false positives. Sonography was negative in 23 newborns (74.2%); 13 of these were positive to pH-monitoring and may therefore be considered as false negatives. Respect to continuous 24-hour pH-monitoring, sonography showed a specificity of 100% but a very low sensitivity of 38% with a positive prediction value of 100% and a negative prediction value of 43%.

CONCLUSIONS

Sonography should not replace 24-hour pH monitoring for detecting GOR in preterm infants. However, sonography has a very high specificity and a positive predictive value of 100%. When clinicians suspect GOR in preterm infants, it could be useful for selection of cases to refer for pH-metry.

Usefulness of a serological panel test in the assessment of gastritis in symptomatic children

BACKGROUND

Non-invasive methods are advisable for the detection of Helicobacter pylori-related chronic gastritis in pediatric patients. Serum pepsinogens I and II (sPGII and sPGII), gastrin-17 (G-17) and anti-H. pylori antibodies (IgG-Hp) have been proposed as a 'serological gastric biopsy'.

AIM

To assess H. pylori infection and to evaluate gastric mucosa status in a pediatric population by means of serological parameters such as sPGI, sPGII, G-17 and IgG-Hp.

METHODS

45 consecutively children evaluated for upper gastrointestinal symptoms were analyzed. All children were submitted to upper gastrointestinal endoscopy with biopsies. Serum samples were analyzed for IgG-Hp, sPGII, sPGI and G-17 (Biohit, Helsinki, Finland).

RESULTS

18 children had H. pylori-related mild or moderate non-atrophic chronic gastritis. They presented significantly higher mean levels of sPGII and of IgG-Hp than negative ones, either under or up to 10 years. sPGI showed significantly increased levels in H. pylori-positive patients only over 10 years. G-17 levels were not different between H. pylori-positive and -negative ones. The best cut-offs of IgG-Hp, sPGII and of product IgG-Hp x sPGII, to identify H. pylori infection, were 30 IU/l, 9 microg/l, and 241 IU/l x microg/l, respectively. The product IgG-Hp x sPGII identified H. pylori infection with a 100% sensitivity, 92% specificity, 90% positive predictive value and 100% negative predictive value. IgG-Hp and IgG-Hp showed a correlation (r = 0.94; p < 0.001).

CONCLUSIONS

Combined analysis of sPGII and IgG-Hp antibody levels could be recommended as a non-invasive panel for the assessment of H. pylori-related histological alterations of gastric mucosa in childhood.

Pulmonary aspiration shown by scintigraphy in gastroesophageal reflux-related respiratory disease

OBJECTIVES

Gastroesophageal reflux (GER) may underlie respiratory manifestations via vagally mediated airway hyperresponsiveness or microaspiration, and intraesophageal pH monitoring is generally used to identify GER in patients with such manifestations. We aimed to establish the frequency of retrograde pulmonary aspiration in patients with unexplained respiratory manifestations.

METHODS

Fifty-one patients with refractory respiratory symptoms (cough, n = 18; pneumonia, n = 14; apnea, n = 8; asthma, n = 7; and laryngitis, n = 4) were prospectively evaluated. They underwent 24-h intraesophageal pH monitoring and gastroesophageal 99Tc scintigraphy with lung scan 18 to 20 h after the test meal.

RESULTS

Thirteen of 51 patients (25.5%) had abnormal intraesophageal pH study results (mean reflux index, 11.3%; range, 6.5 to 50%); and in 25 of 51 patients (49%), overnight scintigraphy showed pulmonary aspiration. Nineteen of these 25 patients had entirely normal pH study results, whereas 6 of 13 patients with abnormal pH study results had aspiration. Pulmonary aspiration was demonstrated in all patients with apnea and 61.5% of patients with recurrent pneumonia. Nine of 25 patients (36%) with aspiration had histologic evidence of esophagitis, whereas histologic esophagitis was present in 5 of 13 patients (38.4%) with pathologic GER as shown by intraesophageal pH monitoring.

CONCLUSIONS

Pulmonary aspiration as demonstrated by overnight scintigraphy is common in children with unexplained and refractory respiratory manifestations, suggesting that GER could be the underlying cause of these manifestations. Since only a few children with chronic or recurrent respiratory symptoms have a pathologic gastroesophageal acid reflux, a normal intraesophageal pH study result does not rule out GER in these children.

Cytokine expression due to Helicobacter pylori in a tissue culture model

Helicobacter pylori, in recent years, has been recognized as the major causative agent in chronic gastritis and peptic ulcer disease in humans. H. pylori is a ubiquitous organism, with at least half of the world's population infected. Of those individuals with peptic ulcer disease, it is estimated that 90% of cases are caused by H. pylori. Currently, the efficacy of therapies is starting to decline due to increasing resistance rates, especially towards clarithromycin. Due to this, new therapies are needed to combat this bacterium. It is hypothesized that cytokine release (especially interleukin-1beta, -6, -8, and TNF-alpha) due to H. pylori infection and the subsequent influx of inflammatory cells causes a massive release of reactive oxygen species (ROS) during the inflammatory reaction. The ROS then cause the pathologic changes seen in the infected tissues. In this study, human gastric adenocarcinoma cell line ATCC 1739 (a cell line not previously evaluated) was examined for its production of interleukin-1beta, -6, -8, and TNF-alpha when cocultured in a ratio of 10:1 H. pylori to adenocarcinoma cells, to determine its value as a model to demonstrate the inflammatory response. Results from this study indicated that ATCC 1739 cells only reliably produced IL-8 when cocultured with H. pylori and stimulated with TNF-alpha. The production of IL-1beta, IL-6, and TNF-alpha by the ATCC 1739 cells was no different in H. pylori-exposed cells than non-exposed cells. It was concluded that the ATCC 1739 cell line is not suitable to study the effects of coculture with H. pylori on cytokine production.

Helicobacter pylori persistence: an overview of interactions between H. pylori and host immune defenses

Helicobacter pylori is a gram-negative bacterium that persistently colonizes more than half of the global human population. In order to successfully colonize the human stomach, H. pylori must initially overcome multiple innate host defenses. Remarkably, H. pylori can persistently colonize the stomach for decades or an entire lifetime despite development of an acquired immune response. This review focuses on the immune response to H. pylori and the mechanisms by which H. pylori resists immune clearance. Three main sections of the review are devoted to (i) analysis of the immune response to H. pylori in humans, (ii) analysis of interactions of H. pylori with host immune defenses in animal models, and (iii) interactions of H. pylori with immune cells in vitro. The topics addressed in this review are important for understanding how H. pylori resists immune clearance and also are relevant for understanding the pathogenesis of diseases caused by H. pylori (peptic ulcer disease, gastric adenocarcinoma, and gastric lymphoma).

Prevalence of Helicobacter pylori vacA, cagA, cagE, iceA, babA2 genotypes and correlation with clinical outcome in Turkish patients with dyspepsia

BACKGROUND

Distinct virulence factors of Helicobacter pylori have been associated with clinical outcome of the infection; however, considerable variations have been reported from different geographic regions and data on genotypes of Turkish H. pylori isolates are sparse.

AIM

To determine the prevalence of specific genotypes of H. pylori in Turkish patients with dyspepsia.

MATERIALS AND METHODS

Ninety-three H. pylori-positive patients [30 with non-ulcer dyspepsia (NUD), 30 with duodenal ulcer (DU), and 33 with gastric cancer (GC)] who were admitted to our endoscopy unit due to dyspepsia were enrolled in the study. H. pylori infection was confirmed in all patients by histology and rapid urease test (RUT). The presence of vacA alleles, cagA, cagE, iceA, and babA2 genotypes were determined by polymerase chain reaction (PCR). Chi-squared test and Fisher's exact test were used for statistical comparisons and multivariate regression analysis was performed to find out independent predictors of different clinical outcomes.

RESULTS

Turkish strains examined predominantly possessed the vacA s1,m2 (48.4%) and s1,m1 (40.7%) genotypes. The vacA s1a genotype was detected in 66.7, 96.4, and 87.9% of isolates from patients with NUD, DU, and GC, respectively, and its presence was significantly associated with that of DU (p = .004), GC (p = .043), and cagA gene (p = .021). None of the cases was found to harbor the s1c genotype. The frequencies of the cagA and cagE genes among studied isolates were 73.6 and 59.3%, respectively. The cagA gene was significantly associated with the presence of DU (p = .004) and GC (p = .003), and the cagE gene, too, was significantly associated with the presence of DU (p = .002) and GC (p = .000). All H. pylori isolates possessed the iceA gene. In all, 68 isolates (74.7%) were positive for iceA1 and 23 (25.3%) for iceA2. The frequency of icea1 gene was significantly higher in cases with GC (85%) than in cases with NUD (60%) (p = .026). The frequency of babA2 gene was 23.3, 46.4, and 87.9% in isolates of patients with NUD, DU, and GC, respectively. When compared to cases with NUD (p = .000) and DU (p = .000), the presence of babA2 gene was significantly higher in cases with GC. Multivariate regression analysis disclosed cagE (p = .006) and vacA s1a (p = .027) genotypes to be independent predictors of DU and babA2 (p = .000) and cagE (p = .013) genotypes to be independent predictors of GC.

CONCLUSIONS

H. pylori vacA s1a, cagA, cagE genotypes have significant relations with the presence of DU and GC, and iceA1, babA2 with GC in Turkish patients with dyspepsia, whereas cagE and vacA s1a genotypes are independent predictors of DU, and babA2 and cagE genotypes are independent predictors of GC.

Gastroduodenal diseases of childhood

PURPOSE OF REVIEW

This paper will review new developments in the etiology and management of gastric and duodenal diseases affecting children.

RECENT FINDINGS

Despite dropping prevalence rates in developed nations, most new Helicobacter pylori infections are primarily acquired during childhood. Resistance to standard triple therapy and falling eradication rates are increasing problems for clinicians, necessitating the study of alternative treatment strategies. Eosinophilic diseases of the gastrointestinal tract are being increasingly recognized. Although population-based epidemiology and the natural history of eosinophilic diseases are not yet fully characterized, biologic therapies are in development for the treatment of these chronic, often refractory, conditions. A recent US National Institutes of Health celiac disease consensus conference suggested that infants' diet constituents and timing of solid food introduction are potential environmental influences in the development of celiac disease.

SUMMARY

New methods of diagnosis and treatment are greatly impacting care of pediatric patients with gastric and duodenal diseases. Less invasive but highly accurate tools for diagnosis are becoming better validated. Early diagnosis and effective intervention in most gastroduodenal disorders of childhood can alter natural history and improve overall quality of life.

Distinct patterns of mucosal apoptosis in H pylori-associated gastric ulcer are associated with altered FasL and perforin cytotoxic pathways

AIM

To analyze the level of apoptosis in different mucosal compartments and the differential expression of Fas/Fas-ligand and perforin in H pylori-associated gastric ulcer.

METHODS

Antral specimens from patients with H pylori-related active gastric ulcer (GU), H pylori-related gastritis, and non-infected controls were analysed for densities and distribution of apoptotic cells determined by the TdT-mediated dUDP-biotin nick-end-labelling method. GU patients were submitted to eradication therapy with follow-up biopsy after 60 d. Fas, FasL, and perforin-expressing cells were assessed by immunoperoxidase, and with anti-CD3, anti-CD20 and anti-CD68 by double immunofluorescence and confocal microscopy. Quantitative analysis was performed using a computer-assisted image analyser.

RESULTS

H pylori-infected antrum showed greater surface epithelial apoptosis which decreased after eradication therapy. In the lamina propria, higher rates of mononuclear cell apoptosis were observed in H pylori-gastritis. Co-expression of Fas with T-cell and macrophage markers was reduced in GU. FasL- and perforin-expressing cells were increased in H pylori-infection and correlated with epithelial apoptosis. Perforin-expressing cells were also increased in GU compared with H pylori-gastritis.

CONCLUSION

Epithelial apoptosis is increased in H pylori-infection and correlates to FasL- and perforin-expression by T cells. Expression of perforin is correlated with the tissue damage, and may represent the enhancement of a distinct cytotoxic pathway in GU. Increased expression of FasL not paralleled by Fas on T-cells and macrophages may indicate a reduced susceptibility to the Fas/FasL-mediated apoptosis of lymphoid cells in H pylori-infection.

Update in the treatment of paediatric ulcerative colitis

Ulcerative colitis is an important disease in the paediatric population. Ulcerative colitis is one of the chronic inflammatory bowel diseases, and is medically incurable. However, the arsenal of medications has grown as knowledge of the pathogenesis of this disease advances. This review looks at the classical treatments for children with ulcerative colitis, including the 5-aminosalicylates, corticosteroids and imunomodulators, as well as biological therapy and other, newer modalities.

The role of tacrolimus in inflammatory bowel disease: a systematic review

Therapeutic management of inflammatory bowel disease remains beyond the limits of conventional therapy in many cases. Novel therapies used include tacrolimus, a new powerful immunosuppressive drug, employed in some case reports and a few studies that have tried to evaluate its effectiveness in Crohn's disease and ulcerative colitis with promising results, but its role in the management of inflammatory bowel disease remains controversial. We performed a systematic review that analyzed a total of 23 reported experiences in 286 patients with inflammatory bowel disease treated with tacrolimus. Although most of the published studies are uncontrolled, short, and heterogeneous, promising results have been obtained in fistulizing disease, unresponsive cases of both ulcerative colitis and Crohn's disease, and even extraintestinal manifestations. The overall outcome was good enough to consider tacrolimus as a rationale therapeutic option. However, comparative studies with standard therapeutic options like infliximab are needed to assess the correct role that tacrolimus may play in these patients.

Medical therapy for refractory pediatric Crohn's disease

Crohn's disease is a common indication for referral to pediatric gastroenterology. While most patients with Crohn's disease respond to standard induction therapy, steroid-refractory or steroid-dependent disease is a frequently encountered problem. This review discusses the data existing in both the adult and pediatric literature for medical therapy of refractory pediatric Crohn's disease.

The Use of Complementary and Alternative Medicine in Children with Chronic Medical Conditions

OBJECTIVES

The objectives of this study were to examine whether progressive medical conditions lead to greater use of complementary and alternative medicine (CAM) as compared with more stable conditions, to see whether disease severity influences CAM use, and to identify the main motivations behind CAM use.

METHODS

Subjects were selected from outpatient clinics at Hotel Dieu Hospital. Surveys were conducted by mail and telephone. Medical diagnosis and severity were obtained from medical files. Statistical tests included chi, Kruskal-Wallis, and correlations.

RESULTS

One hundred ninety-four children were surveyed. The "progressive" group included 15 patients with Duchenne muscular dystrophy and 22 patients with cystic fibrosis. The "nonprogressive" group included 85 patients with cerebral palsy (CP), 49 with diabetes mellitus, and 23 with spina bifida. Twenty-three percent were using CAM. CP had the highest use; diabetes mellitus had the lowest. Popular therapies included massage and dietary/herbal remedies. Progressiveness had no impact on CAM use. Within the CP group, greater disease severity was associated with higher use (P < 0.001). The main reason for CAM use was to complement conventional medicine.

CONCLUSIONS

Disease progressiveness had no impact on CAM use, but severity within the CP group did. Complementing conventional medicine was the main motive. Understanding the reasons and patterns of use of CAM is beneficial in efforts to improve the care of children with chronic medical conditions.

Alzheimer's disease and Helicobacter pylori infection: Defective immune regulation and apoptosis as proposed common links

Although degenerative diseases of the central nervous system, including Alzheimer's disease (AD), have an increasingly high impact on aged population their association with Helicobacter pylori (H. pylori) infection has not as yet been thoroughly researched. Current H. pylori infection appears to induce irregular humoral and cellular immune responses that, owing to the sharing of homologous epitopes (molecular mimicry), cross-react with components of nerves, thereby contributing and possibly perpetuating the apoptotic neural tissue damage observed in neurodegenerative diseases including AD. An association between AD and H. pylori infection has been recently addressed by two studies. A higher seropositivity for anti-H. pylori immunoglobulin G antibodies in 30 patients with AD than in 30 age-matched controls was reported in one study; this serological test, however, has limitations because it does not discriminate between current and old infections. In the other study, by introducing the histological method (the actual gold standard) for diagnosis of H. pylori infection, we reported a higher prevalence of H. pylori infection in 50 AD patients than in 30 anemic controls. This pathogen may influence the pathophysiology of AD by promoting platelet and platelet-leukocyte aggregation; releasing various pro-inflammatory and vasoactive substances; developing cross-mimicry with host antigens; producing reactive oxygen metabolites and circulating lipid peroxides; influencing the apoptotic process; and increasing, through induction of atrophic gastritis, homocysteine, which contributes to vascular disorders implicated in endothelial damage and neurodegeneration.

H pylori receptor MHC class II contributes to the dynamic gastric epithelial apoptotic response

AIM: To investigate the role of MHC class II in the modulation of gastric epithelial cell apoptosis induced by H pylori infection.

METHODS: After stimulating a human gastric epithelial cell line with bacteria or agonist antibodies specific for MHC class II and CD95, the quantitation of apoptotic and anti-apoptotic events, including caspase activation, BCL-2 activation, and FADD recruitment, was performed with a fluorometric assay, a cytometric bead array, and confocal microscopy, respectively.

RESULTS: Pretreatment of N87 cells with the anti-MHC class II IgM antibody RFD1 resulted in a reduction in global caspase activation at 24 h of H pylori infection. When caspase 3 activation was specifically measured, crosslinking of MHC class II resulted in a marked reduced caspase activation, while simple ligation of MHC class II did not. Crosslinking of MHC class II also resulted in an increased activation of the anti-apoptosis molecule BCL-2 compared to simple ligation. Confocal microscope analysis demonstrated that the pretreatment of gastric epithelial cells with a crosslinking anti-MHC class II IgM blocked the recruitment of FADD to the cell surface.

CONCLUSION: The results presented here demonstrate that the ability of MHC class II to modulate gastric epithelial apoptosis is at least partially dependent on its crosslinking. Furthermore, while previous research has demonstrated that MHC class II signaling can be pro-apoptotic during extended ligation, we have shown that the crosslinking of this molecule has anti-apoptotic effects during the earlier time points of H pylori infection. This effect is possibly mediated by the ability of MHC class II to modulate the activation of the pro-apoptotic receptor Fas by blocking the recruitment of the accessory molecule FADD, and this delay in apoptosis induction could allow for prolonged cytokine secretion by H pylori-infected gastric epithelial cells.

Contemporary morphologic definition of backwash ileitis in ulcerative colitis and features that distinguish it from Crohn disease

Terminal ileum (TI) sections from 250 ulcerative colitis (UC) total colectomy specimens resected during 3 periods and endoscopic TI biopsy specimens from 100 contemporary chronic UC and 100 Crohn disease (CD) patients were reviewed. The respective proportions of cases resected during the 3 periods with moderately or markedly active cecal UC were 72%, 34%, and 2% and with moderate or marked backwash ileitis (BWI), 21%, 18%, and 0%. The activity level of BWI correlated with level of cecal UC. In contemporary initial endoscopic TI biopsy specimens, 6% of chronic UC patients had BWI, all with moderately to markedly active cecal chronic UC. In CD cases, 75% had chronic or active enteritis, consisting of patchy lamina propria edema containing mildly active inflammation, crypt disarray, and focally blunted or flattened villi. Mucous gland metaplasia was present in 27% of CD biopsy specimens. BWI should be restricted to active enteritis that involves the ileum in a contiguous pattern from the cecum that has a similar or greater degree of active inflammation. Mild BWI predominantly involves the superficial mucosa in a contiguous pattern. Focal isolated ileal erosions, mucous gland metaplasia, or patchy edema with mild active inflammation are features of CD.

Pepsin, a reliable marker of gastric aspiration, is frequently detected in tracheal aspirates from premature ventilated neonates: relationship with feeding and methylxanthine therapy

OBJECTIVES

To determine the frequency of pepsin detection in tracheal aspirate (TA) samples of mechanically ventilated premature neonates and its association with feedings and methylxanthine therapy.

PATIENTS AND METHODS

Serial TA samples (days 1, 3, 5, 7, 14, 21, 28 and >28 days) were collected from premature neonates receiving ventilatory support. An enzymatic assay with a fluorescent substrate was used to detect pepsin. Pepsin was also measured in 10 serum samples collected in conjunction with the TA samples from 8 neonates.

RESULTS

A total of 239 TA samples was collected from 45 premature neonates (mean birth weight, 762 +/- 166 g; mean gestational age, 25.5 +/- 1.5 wk). Pepsin was detectable in 222 of 239 TA samples (92.8%) and in none of the serum samples. Pepsin was significantly lower on day 1 (mean, 170 +/- 216 ng/mL) when compared with all other time points (P < 0.05). Mean concentration of pepsin was significantly lower when infants were unfed (265 +/- 209 ng/mL) compared with levels during feeding (390 +/- 260 ng/mL, P = 0.02). The mean level of pepsin was significantly higher in infants during xanthine therapy (419 +/- 370 ng/mL) compared with no xanthine therapy (295 +/- 231 ng/mL, P = 0.037).

CONCLUSION

Pepsin, a marker of gastric contents, was detected in more than 92% of TA samples from premature infants on mechanical ventilation. The level of pepsin was higher in fed infants when compared with unfed infants. Xanthine therapy was also associated with increased pepsin in TA samples. Chronic aspiration of gastric contents may worsen lung disease in premature infants.

Helicobacter pylori genotypes in children from a population at high gastric cancer risk: no association with gastroduodenal histopathology

OBJECTIVES

Both bacterial and host determinants underlying differences in histopathology and clinical outcome in H. pylori pediatric infection, as compared to adults, are still poorly documented. Pediatric studies may provide important insights on H. pylori infection immunopathogenesis, particularly in high gastric cancer risk populations. The present study concerns H. pylori genotypic diversity of isolates in children from a population with high gastric cancer risk, and its association with demographic and clinical variables, including gastroduodenal endoscopic and histopathological features.

METHODS

A total of 119 subjects (mean age 10.3 yr, 1.5-18.0 yr) with H. pylori infection were studied. H. pylori vacA, cagA, and iceA genotypes were determined (PCR) in antral-obtained primary cultures; histopathological evaluation was performed in corpus, antrum, and duodenum biopsy specimens.

RESULTS

cagA-, vacA s2m2, and iceA2 were the most prevalent genotypes. No association was observed between H. pylori genotypes and subject demographic and clinical variables, with the exception of a significant association between vacA s2 genotype and lower corpus inflammation score (p< 0.03).

CONCLUSIONS

In this pediatric cohort, H. pylori genotype profiles were distinct from those reported in adult subjects in the same area, with a lower prevalence of the putative more virulent genotypes. Moreover, they were not associated with clinical expression of gastroduodenal disease, suggesting the potential role of host and/or environmental factors for the development of clinical disease at a later age.