Enteroscopy in children and adults with inflammatory bowel disease

Inflammatory bowel disease (IBD) includes Crohn's disease (CD), ulcerative colitis and unclassified entities. CD commonly involves the terminal ileum and colon but at the time of diagnosis it can be confined to the small bowel (SB) in about 30% of the patients, especially in the young ones. Management of isolated SB-CD can be challenging and objective evaluation of the SB mucosa is essential in differentiating CD from other enteropathies to achieve therapeutic decisions and to plan the follow-up. The introduction of cross-sectional imaging techniques and capsule endoscopy (CE) have significantly expanded the ability to diagnose SB diseases providing a non-invasive test for the visualization of the entire SB mucosa. The main CE limitations are the low specificity, the lack of therapeutic capabilities and the impossibility to take biopsies. Device assisted enteroscopy (DAE) enables histological confirmation when traditional endoscopy, capsule endoscopy and cross-sectional imaging are inconclusive and also allows therapeutic interventions such as balloon stricture dilation, intralesional steroid injection, capsule retrieval and more recently stent insertion. In the current review we will discuss technical aspect, indications and safety profile of DAE in children and adults with IBD

Faecal calprotectin and ultrasonography as non-invasive screening tools for detecting colorectal polyps in children with sporadic rectal bleeding. a prospective study

Background: Colorectal polyps are reported in 6,1% of paediatric colonoscopies and in 12% of those performed for lower gastrointestinal bleeding. Although colonoscopy is widely used in paediatric patients, it requires bowel preparation and general anaesthesia or deep sedation, and in rare cases, it can cause complications. Non-invasive screening techniques able to predict polyps in children with isolated and sporadic rectal bleeding may play a key role in the selection of patients needing colonoscopy. Methods: We enrolled all children undergoing colonoscopy for isolated and sporadic rectal bleeding to determine the diagnostic accuracy of faecal calprotectin, ultrasonography (US) and digital rectal examination as diagnostic methods for screening colorectal polyps. Results: A total of 26 of 59 enrolled patients (44.1%) had colonic polyps, one patient had multiple polyps, and 23% of children had polyps proximal to the splenic flexure. The diagnostic accuracy of faecal calprotectin for detecting colorectal polyps was 96.6%, with a sensitivity of 100%. False-positive faecal calprotectin was shown in 2 patients with non-steroidal anti-inflammatory drug-related lesions. The diagnostic accuracy of ultrasound was 77.9%. Polyps not seen with ultrasound tended to be relatively smaller (1.5 vs 2.3, p = 0.001) and located in the rectum. The combined use of FC, US and digital rectal examination obtained a specificity and PPV of 100%. Conclusions: FC combined with US and digital rectal examination is a good and promising non-invasive screening test for detecting colorectal polyps in children with isolated and sporadic rectal bleeding

Tolerogenic IL-10-engineered dendritic cell-based therapy to restore antigen-specific tolerance in T cell mediated diseases

Tolerogenic dendritic cells play a critical role in promoting antigen-specific tolerance via dampening of T cell responses, induction of pathogenic T cell exhaustion and antigen-specific regulatory T cells. Here we efficiently generate tolerogenic dendritic cells by genetic engineering of monocytes with lentiviral vectors co-encoding for immunodominant antigen-derived peptides and IL-10. These transduced dendritic cells (designated DCIL-10/Ag) secrete IL-10 and efficiently downregulate antigen-specific CD4+ and CD8+ T cell responses from healthy subjects and celiac disease patients in vitro. In addition, DCIL-10/Ag induce antigen-specific CD49b+LAG-3+ T cells, which display the T regulatory type 1 (Tr1) cell gene signature. Administration of DCIL-10/Ag resulted in the induction of antigen-specific Tr1 cells in chimeric transplanted mice and the prevention of type 1 diabetes in pre-clinical disease models. Subsequent transfer of these antigen-specific T cells completely prevented type 1 diabetes development. Collectively these data indicate that DCIL-10/Ag represent a platform to induce stable antigen-specific tolerance to control T-cell mediated diseases

Bcl-2 Regulates HIF-1α Protein Stabilization in Hypoxic Melanoma Cells via the Molecular Chaperone HSP90

Hypoxia-Inducible Factor 1 (HIF-1) is a transcription factor that is a critical mediator of the cellular response to hypoxia. Enhanced levels of HIF-1alpha, the oxygen-regulated subunit of HIF-1, is often associated with increased tumour angiogenesis, metastasis, therapeutic resistance and poor prognosis. It is in this context that we previously demonstrated that under hypoxia, bcl-2 protein promotes HIF-1/Vascular Endothelial Growth Factor (VEGF)-mediated tumour angiogenesis.By using human melanoma cell lines and their stable or transient derivative bcl-2 overexpressing cells, the current study identified HIF-1alpha protein stabilization as a key regulator for the induction of HIF-1 by bcl-2 under hypoxia. We also demonstrated that bcl-2-induced accumulation of HIF-1alpha protein during hypoxia was not due to an increased gene transcription or protein synthesis. In fact, it was related to a modulation of HIF-1alpha protein expression at a post-translational level, indeed its degradation rate was faster in the control lines than in bcl-2 transfectants. The bcl-2-induced HIF-1alpha stabilization in response to low oxygen tension conditions was achieved through the impairment of ubiquitin-dependent HIF-1alpha degradation involving the molecular chaperone HSP90, but it was not dependent on the prolyl hydroxylation of HIF-1alpha protein. We also showed that bcl-2, HIF-1alpha and HSP90 proteins form a tri-complex that may contribute to enhancing the stability of the HIF-1alpha protein in bcl-2 overexpressing clones under hypoxic conditions. Finally, by using genetic and pharmacological approaches we proved that HSP90 is involved in bcl-2-dependent stabilization of HIF-1alpha protein during hypoxia, and in particular the isoform HSP90beta is the main player in this phenomenon.We identified the stabilization of HIF-1alpha protein as a mechanism through which bcl-2 induces the activation of HIF-1 in hypoxic tumour cells involving the beta isoform of molecular chaperone HSP90

Bcl-2 regulates HIF-1alpha protein stabilization in hypoxic melanoma cells via the molecular chaperone HSP90.

BACKGROUND: Hypoxia-Inducible Factor 1 (HIF-1) is a transcription factor that is a critical mediator of the cellular response to hypoxia. Enhanced levels of HIF-1alpha, the oxygen-regulated subunit of HIF-1, is often associated with increased tumour angiogenesis, metastasis, therapeutic resistance and poor prognosis. It is in this context that we previously demonstrated that under hypoxia, bcl-2 protein promotes HIF-1/Vascular Endothelial Growth Factor (VEGF)-mediated tumour angiogenesis. METHODOLOGY/PRINCIPAL FINDINGS: By using human melanoma cell lines and their stable or transient derivative bcl-2 overexpressing cells, the current study identified HIF-1alpha protein stabilization as a key regulator for the induction of HIF-1 by bcl-2 under hypoxia. We also demonstrated that bcl-2-induced accumulation of HIF-1alpha protein during hypoxia was not due to an increased gene transcription or protein synthesis. In fact, it was related to a modulation of HIF-1alpha protein expression at a post-translational level, indeed its degradation rate was faster in the control lines than in bcl-2 transfectants. The bcl-2-induced HIF-1alpha stabilization in response to low oxygen tension conditions was achieved through the impairment of ubiquitin-dependent HIF-1alpha degradation involving the molecular chaperone HSP90, but it was not dependent on the prolyl hydroxylation of HIF-1alpha protein. We also showed that bcl-2, HIF-1alpha and HSP90 proteins form a tri-complex that may contribute to enhancing the stability of the HIF-1alpha protein in bcl-2 overexpressing clones under hypoxic conditions. Finally, by using genetic and pharmacological approaches we proved that HSP90 is involved in bcl-2-dependent stabilization of HIF-1alpha protein during hypoxia, and in particular the isoform HSP90beta is the main player in this phenomenon. CONCLUSIONS/SIGNIFICANCE: We identified the stabilization of HIF-1alpha protein as a mechanism through which bcl-2 induces the activation of HIF-1 in hypoxic tumour cells involving the beta isoform of molecular chaperone HSP90

478 Bcl-2 regulates HIF-1a protein stabilization in hypoxic melanoma cells via the molecular chaperone HSP90b

BACKGROUND: Hypoxia-Inducible Factor 1 (HIF-1) is a transcription factor that is a critical mediator of the cellular response to hypoxia. Enhanced levels of HIF-1alpha, the oxygen-regulated subunit of HIF-1, is often associated with increased tumour angiogenesis, metastasis, therapeutic resistance and poor prognosis. It is in this context that we previously demonstrated that under hypoxia, bcl-2 protein promotes HIF-1/Vascular Endothelial Growth Factor (VEGF)-mediated tumour angiogenesis. METHODOLOGY/PRINCIPAL FINDINGS: By using human melanoma cell lines and their stable or transient derivative bcl-2 overexpressing cells, the current study identified HIF-1alpha protein stabilization as a key regulator for the induction of HIF-1 by bcl-2 under hypoxia. We also demonstrated that bcl-2-induced accumulation of HIF-1alpha protein during hypoxia was not due to an increased gene transcription or protein synthesis. In fact, it was related to a modulation of HIF-1alpha protein expression at a post-translational level, indeed its degradation rate was faster in the control lines than in bcl-2 transfectants. The bcl-2-induced HIF-1alpha stabilization in response to low oxygen tension conditions was achieved through the impairment of ubiquitin-dependent HIF-1alpha degradation involving the molecular chaperone HSP90, but it was not dependent on the prolyl hydroxylation of HIF-1alpha protein. We also showed that bcl-2, HIF-1alpha and HSP90 proteins form a tri-complex that may contribute to enhancing the stability of the HIF-1alpha protein in bcl-2 overexpressing clones under hypoxic conditions. Finally, by using genetic and pharmacological approaches we proved that HSP90 is involved in bcl-2-dependent stabilization of HIF-1alpha protein during hypoxia, and in particular the isoform HSP90beta is the main player in this phenomenon. CONCLUSIONS/SIGNIFICANCE: We identified the stabilization of HIF-1alpha protein as a mechanism through which bcl-2 induces the activation of HIF-1 in hypoxic tumour cells involving the beta isoform of molecular chaperone HSP90

Isolated intestinal Ganglioneuromatosis: case report and literature review

Background: Intestinal Ganglioneuromatosis (IG) is a rare disorder of the enteric nervous system. In pediatric age it is often associated with genetic syndromes such as Neurofibromatosis 1 (NF1), multiple endocrine neoplasia type 2B (MEN2B) and Cowden syndrome (PTEN mutation), and ganglioneuromas (GNs) may be sometimes the first sign of the disease. Isolated GNs are rare and sporadic. Clinical symptom vary and depend on the size and on the location of the GNs. This disorder affects intestinal motility and it, consequently, causes changes in bowel habits, abdominal pain, occlusive symptoms and rarely lower gastrointestinal bleeding secondary to ulceration of the intestinal mucosa. On the other hand, patients can remain asymptomatic for many years. Case presentation: We describe a 9-year-old boy referred to our emergency department for right lower quadrant abdominal pain. No familial history for gastrointestinal disorders. No history of fever or weight loss. At physical examination, he had diffused abdominal pain. Abdominal ultrasonography showed a hypoechoic formation measuring 41.8 mm by 35 mm in the right lower quadrant of the abdomen. Routine blood tests were normal, but fecal occult blood test was positive. Abdominal TC confirmed the hypodense formation, of about 5 cm in transverse diameter, in the right hypochondrium that apparently invaginated in the caecum-last ileal loop. Colonoscopy showed in the cecum an invaginated polypoid lesion of the terminal ileal loop. Laparoscopic resection of the polypoid lesion was performed. Histological diagnosis of the large neoplasm observed in the terminal ileum was diffuse ganglioneuromatosis. NF1, RET and PTEN gene tests resulted negative for specific mutations. At the 1 year follow-up, the patient presented good general condition and blood tests, fecal occult blood test, esophagogastroduodenoscopy, colonoscopy and MR-enterography were negative. Conclusions: Only few cases are reported in literature of IG in pediatric age. Although rare, the present case suggests that this disorder must be taken in consideration in every patient with GI symptoms such as abdominal pain, constipation, lower intestinal bleeding, in order to avoid a delayed diagnosis

Eosinophilic esophagitis in children: clinical findings and diagnostic approach

Eosinophilic esophagitis (EoE) is an emerging chronic immune and antigen-mediated clinicopathologic disease. During the last 2 decades, the incidence of this condition in children has increased significantly, thanks to practitioners for creating the awareness and higher use of diagnostic endoscopy. We have analysed paediatric literature on EoE focusing on the epidemiology, pathophysiology, clinical findings and diagnostic approach. EoE is pathogenically related to a Th2 inflammation characterized by a mixed IgE and non-IgEmediated reaction to food and/or environmental agents. This leads to esophageal dysfunction and remodeling accompanied by subepithelial fibrosis. EoE can be presented with several range of gastrointestinal symptoms, including regurgitation, vomiting, feeding difficulties or feeding refusal in infants and toddlers, as well as heartburn, dysphagia and food bolus impaction in older children and adults. The diagnostic suspicion is based on the presence of chronic symptoms of esophgeal dysfunction and esophageal eosinophilia characterised histologically by a significant eosinophilic infiltration of the oesophageal mucosa (>15 eosinophils per high powered field). In this review, we will provide an update on clinical presentation and diagnostic approach to EoE in children. We emphasized on the relevant aspects of the new clinical condition termed “PPI responsive esophageal eosinophilia”, as entities distinct from EoE and the role of PPI trial in the diagnostic workup, therefore we proposed a new diagnostic algorithm

Omental Infarction

To evaluate the prevalence of omental infarction (OI) in children with suspected appendicitis, the role of ultrasonography (US) in its diagnosis and management and the efficacy of conservative management