Inflammatory bowel disease (IBD) is an immune-mediated inflammatory condition causing inflammation of gastrointestinal and systemic cells, with an increasing prevalence worldwide. Many factors are known to trigger and maintain inflammation in IBD including the innate and adaptive immune systems, genetics, the gastrointestinal microbiome and several environmental factors. Our knowledge of the involvement of the immune system in the pathophysiology of IBD has advanced rapidly over the last two decades, leading to the development of several immune-targeted treatments with a biological source, known as biologic agents. The initial focus of these agents was directed against the pro-inflammatory cytokine tumor necrosis factor-α (TNF-α) leading to dramatic changes in the disease course for a proportion of patients with IBD. However, more recently, it has been shown that a significant proportion of patients do not respond to anti-TNF-α directed therapies, leading a shift to other inflammatory pathways and targets, including those of both the innate and adaptive immune systems, and targets linking both systems including anti-leukocyte trafficking agents-integrins and adhesion molecules. This review briefly describes the molecular basis of immune based gastrointestinal inflammation in IBD, and then describes how several current and future biologic agents work to manipulate these pathways, and their clinical success to date.

Objective. Gastrointestinal angiodysplasias recurrently bleed, accounting for 3–5% of obscure gastrointestinal bleeding. The advent of small bowel capsule endoscopy (SBCE) has led to an increased recognition of small bowel angiodysplasias (SBAs) but little is known about their etiology. Previous small cohorts and case reports suggest an equal gender incidence and associations with cardiovascular disease, renal impairment, and coagulopathies. Methods. Patients with SBA were identified from our SBCE database. A control group, in whom gastrointestinal bleeding had been excluded, was also identified. Information on patient demographics, past medical/surgical/social history and medications was prospectively obtained. Results. A total of 82 patients and 95 controls were identified. Data was available from 81% (n = 66) of SBA patients. The mean age of patients and controls was 66.9 years (35–90) and 69.2 years (54–77), and 60% (n = 40) and 58% (n = 55) were females, respectively. There was a higher rate of all comorbidities in the SBA group 92% (61/66) versus controls 76% (72/95) p < 0.002. Significant associations were found with: hypertension (odds ratio [OR] 2.8), ischemic heart disease (OR 4.25), arrhythmias (OR 4.36), valvular heart disease (OR 18), congestive heart failure (OR 4.22), chronic kidney disease (CKD) (OR 8.4), chronic respiratory conditions (OR 2.0), and previous venous thromboembolism (VTE) (OR 6.4). Anticoagulant use was higher in patients with SBA, 50% (n = 33) versus 27% (n = 26) of controls, p < 0.002, specifically warfarin and asasantin retard. Conclusions. SBA occurs in elderly patients with cardiovascular disease and CKD, as previously suggested. This study identifies a previously unrecognised risk in females, patients with chronic respiratory conditions and VTE, and the use of warfarin and asasantin retard. These associations should raise awareness of possible underlying SBA in risk patients with anemia.

Background Small bowel angiodysplasias (SBA) account for 50% of obscure gastrointestinal bleeding. Lesions bleed recurrently and current treatments are relatively ineffective at reducing re-bleeding. Little is known about the natural history of SBA which is needed to guide treatment decisions and counsel patients on prognosis. Aim The aim of this study is to describe the natural history of a cohort of patients with SBA. Methods Patients with SBA were identified retrospectively and clinical and outcome information were collected. Logistic regression analysis was performed to identify factors associated with re-bleeding. Results SBAs were found in 86 patients of which 54% (n = 47) were female, and the average age was 71.6 years. The majority (69%) had multiple lesions, mean of 2.76/patient, and 65% were located in the jejunum. Follow-up was available in 65% (n = 56). There was a significant increase in haemoglobin level from 10.05g/dL to 11.94g/dL, p < 0.001 after mean follow up of 31.9 (6–62) months. Re-bleeding events occurred in 80% (n = 45), with an average of 2.91/person. The mean interval between diagnosis and the first re-bleeding event was 10.7 months. Of the group overall, 70% (n = 40) required transfusions during follow up, and 67% required hospitalisation due to re-bleeding. About 50% received a directed treatment, including argon plasma coagulation, somatostatin analogues, or surgical resection. A total of 3.5% (n = 2) died as a direct consequence of bleeding from SBAs. Multiple lesions (p = 0.048) and valvular heart disease (p = 0.034) were predictive of re-bleeding. Conclusion Our results show the significant impact of SBA on patients' morbidity, with high rates of re-bleeding, persistent anaemia and a mortality rate of 3.5%, despite the use of currently available medical and endoscopic therapies.

Hereditary hemorrhagic teleangectasia (HHT, or Rendu-Osler-Weber disease) is a rare inherited syndrome, characterized by arterio-venous malformations (AVMs or Telangiectasia). The most important and common manifestation is nose bleeds (epistaxis). The telangiectasias (small AVMs) are most evident on the lips, tongue, buccal mucosa, face, chest, and fingers, however; large arterio-venous malformations can also occur in the lungs, liver, pancreas, or brain. Telangiectasias in the upper gastrointestinal tract are known to occur, however data regarding possible small-bowel involvement is limited due to technical difficulties in visualizing the entire gastrointestinal tract. The occurrence of AVMs in the stomach and small bowel can result in chronic bleeding and anaemia. Less frequently, this may occur due to bleeding from oesophageal varices, as patients with HHT can develop hepatic parenchymal AVMs or vascular shunts which cause hepatic cirrhosis and portal hypertension. Gastroenterologists have a crucial role in the management of these patients, however difficulties remain in the detection and management of complications of HHT in the gastrointestinal tract.

Introduction Small bowel capsule endoscopy (SBCE) is a useful diagnostic modality in small bowel disorders. Iron deficiency anaemia (IDA) is one of the most common indications for SBCE. However, there are limited data on the diagnostic yield for IDA alone, and little is known about the clinical impact and long-term outcome of patients following SBCE. Aim To determine the diagnostic yield of SBCE in IDA and to examine outcome. Materials and methods A retrospective review of a tertiary referral centre’s database over a 21-month time period was carried out. Information on follow-up and management was obtained through chart review. Results In all, 309 SBCEs were identified, 30% (n=93) for anaemia and in 70% (n=65), follow-up data were available. The small bowel diagnostic yield for IDA was 53% (n=35), including angiodysplasia 49% (n=17), nonspecific inflammation 34% (n=12), active bleeding 11% (n=4) and Crohn’s disease 6% (n=2). In addition, 16% (n=10) had abnormalities (gastritis, gastric antral vascular ectasia, duodenitis) outside the small bowel. In all, 42% (n=27) were persistently anaemic after a mean follow-up of 9.3 months. Of these, 52% (n=14) and 48% (n=13) had positive and negative SBCEs, respectively. In total, SBCE led to a change in treatment in 28 patients (44%), of whom 17 (61%) remained anaemic. Conclusion This study shows a high overall diagnostic yield for SBCE in IDA 71% (n=45). Despite the majority, 53% (n=24), of patients with positive tests receiving specific treatment, 61% (n=17) remained anaemic in the long term. SBCE results were not predictive of long-term outcome even when stratified for a change in management.

Infliximab is an effective treatment for inflammatory bowel disease (IBD). Studies differ regarding the influence of body mass index (BMI) on the response to infliximab, with the majority of studies indicating that increased BMI may be associated with a poorer response to Infliximab. However, the pharmacokinetic mechanisms causing this have not yet been reported. Examine the correlation between BMI/immunosuppressant use with clinical response, trough and post-infusion levels of infliximab, tumour necrosis factor-α(TNF-α) and anti-drug antibodies(ATI), and determine if these factors can predict future response. We collected serum from 24 patients receiving Infliximab before and 30 minutes following infusion. Clinical parameters were collected retrospectively and prospectively. ELISA measurements of infliximab, TNF-α and ATI were performed. We confirmed that patients with higher infliximab trough levels have a better response rate and that patients with an elevated BMI display a higher rate of loss of response (20%). Patients with a higher BMI had elevated post-infusion levels of infliximab. Additionally, the ratio of IFX/TNF-α trough levels correlated with clinical response to the following infusion. This study confirms that an elevated BMI is associated with a poorer response to infliximab. For the first time, we describe that a higher BMI correlates with higher post-infusion levels, however this does not correlate with a higher rate of response to the drug, suggesting that circulating drug levels do not correlate with tissue levels. Furthermore, in our small cohort of patients, we identified a possible predictive marker of future response to treatment which may be used to guide dose escalation and predict non-response to infliximab.