Pregnancy and inflammatory bowel disease.

Conclusions about the relationship between the pathophysiology and treatment of inflammatory bowel disease and the physiology and management of pregnancy are based on the results of several large physician surveys and retrospective chart reviews. Patients with active disease fare worse than those with inactive disease. There is little evidence that pregnancy affects the course of inflammatory bowel disease or that inactive inflammatory bowel disease affects the course of pregnancy. Judicious medical therapy is effective in controlling inflammatory bowel disease during pregnancy. Sulfasalazine or steroid therapy should not be withdrawn in a patient who needs it to achieve or maintain a quiescent state of inflammatory bowel disease during the course of pregnancy. Immunosuppressive therapy should be avoided. Aggressive medical therapy with total parenteral nutrition in a team approach with a gastroenterologist, surgeon, and perinatologist usually avoids the need for surgical intervention during pregnancy with a good fetal outcome in a patient whose disease is active. Contraception against pregnancy need only be considered in those patients whose disease is so severe that operative therapy is imminent.     

The nonspecific nature of fibrin thrombi in ischemic bowel disease.

Twenty cases of ischemic bowel disease were analysed to determine the frequency and significance of fibrin thrombi in this condition. Fibrin thrombi were present in all 10 patients with occlusive ischemic bowel disease and in 7 of the 10 patients with nonocclusive ischemic bowel disease. In addition, fibrin thrombi were noted in a wide variety of specific and nonspecific inflammatory bowel diseases and in acute appendicitis. We conclude that fibrin thrombi are a nonspecific feature of tissue necrosis and that their mere presence in the bowel should not be regarded as an expression of disseminated intravascular coagulation.     

A primary dysregulation in the immunoregulatory role of the intestinal mucosal epithelial cell in inflammatory bowel disease pathogenesis? Biology of inflammatory response as tissue pattern entities in Crohn's versus ulcerative colitis

Within a framework of dual involvement of mucosa and submucosa on the one hand, and of the muscularis propria of the bowel wall on the other, it might be valid to consider involvement of the vascular supply as the essential means in itself of not only causing the morphologic lesions in inflammatory bowel disease, but also especially in accounting for persisting patterns of inflammatory response both in ulcerative colitis and in Crohn's disease. Inflammatory bowel disease as a group constitutes a spectrum of biologic and pathobiologic manifestations in terms not only of inflammatory involvement of the bowel wall but also in terms of how the bowel in its turn deals with inflammation as a pathologic lesion in its own right. Parameters of inflammatory bowel activity transcend simple concepts of etiology and pathogenesis as applicable to category disorders such as infections or bowel ischemia. Indeed, the strictly characterized initiation of the inflammatory bowel response as a function of defective regulation of the antigenicity of the luminal contents on the one hand, and on interactions between nitric oxide and free oxygen radicals on the other, might help determine a persistence of tissue damage in inflammatory bowel disease that is either relapsing/remitting or chronic in progression. In a final analysis, perhaps, there might be involved a single central form of pathway induction of dysregulated immune reactivity arising from an early disturbance in activation patterns as induced by the onset of luminal antigenicity at an early or specific-stage, further characterized perhaps by specific forms of intestinal epithelial defects of the bowel mucosa in patients subsequently developing inflammatory bowel disease. Specific genetic markers for disease susceptibility and for therapeutic responsiveness are particularly of interest. The Nucleotide binding oligomerization Domain 2 (NOD2) would recognize microbial lipopolysaccharide or else mark systemic responses to pathogens that are pathogenic to evolving inflammatory bowel disease.     

Medical treatment of inflammatory bowel disease: new therapies,new drugs.

Ulcerative colitis, ulcerative proctitis and Crohn''s disease are chronic inflammatory conditions that affect the gastrointestinal tract. Conventional treatment has stressed the role of anti-inflammatory agents to suppress the inflammatory response. New compounds that can deliver 5-aminosalicylic acid to the colon have recently been released in Canada. Metronidazole and azathioprine may also be of benefit in Crohn''s disease. Therapy with cyclosporine and clonidine should be based on the results of further clinical trials. The use of nutritional support as primary therapy in Crohn''s disease appears promising. At present, both pharmacologic and nutritional therapies should be considered in the treatment of inflammatory bowel disease.     

Immunomodulatory benefits of cyclosporine A in inflammatory bowel disease

Etiopathogenesis of mucosal inflammation in inflammatory bowel disease remains a complex and enigmatic field; various factors (genetic, environmental and microbial) trigger an event that activates intestinal immune and nonimmune systems culminating in inflammation and tissue injury. Specifically, both innate and adaptive immune systems seem to play important roles in the pathophysiology of this disease. Cyclosporine A represents a macrolide immune modulator with primary inhibitory effects on T helper lymphocyte production of interleukin-2, and other cytokines leading to altered T-lymphocyte and B-lymphocyte function. The diversity of its therapeutic outcome reported in inflammatory bowel disease may be due to the intricate immuno-pathogenic profile of the disease and the variety of the applied dose-dependent courses of therapy. Cyclosporine A exerts additional actions on other components of the inflammatory infiltrate, including neutrophils and mast cells, thereby appearing to be a multi-dynamic therapeutic approach, although with potential drawbacks, that may be applied alone or combined with other immunomodulatory agents in inflammatory bowel disease patients. Because cyclosporine A induces apoptosis of T-lymphocytes responsible for perpetuation of the chronic inflammatory process in the disease with potential tumorigenic effect, it may exert a further inhibitory effect on cancer development in inflammatory bowel disease patients, and can be combined with other relative agents, such as rapamycin, which also promotes T-lymphocyte apoptosis. Therefore, recently established multifactorial action of cyclosporine A in relation to the pathogenesis of the disease can open new horizons for prospective, controlled trials in large cohorts, aiming to emphasize cyclosporine A's potential.     

Soporte nutricional basado en la evidencia en la enfermedad inflamatoria intestinal

Patients with inflammatory bowel disease are at risk for malnutrition. Consequently all patients with inflammatory bowel disease should undergo nutritional screening to identify those who require thorough nutritional evaluation. When nutritional support is indicated, enteral nutrition (oral or through a tube) should be used. There are no significant differences between elemental and non-elemental enteral diets in inducing remission of Crohn's disease (CD). Nevertheless, given that non-elemental diets are better tolerated, most authors prefer polymeric diets. Enteral nutrition should not be used as the primary treatment of choice in patients with CD, since they are less effective in inducing remission than steroid therapy. Although dietary fat (quantity and type of fat) might influence the course of the disease, recommendations cannot be made on the basis of the available studies. Equally, there is insufficient evidence that glutamine is effective in inducing remission in CD. The use of probiotics presents a high level of evidence in maintenance treatment and in the prevention of postoperative pouchitis, although the level of evidence is lower in ulcerative colitis and CD. Further studies are required to investigate several issues such as dose, treatment duration, the separate or combined use of several strains, as well as the concomitant use of prebiotics, symbiotics or antibiotics.     

The influence of lactose intolerance and other gastro-intestinal tract disorders on L-thyroxine absorption

The preferred treatment for hypothyroidism is oral levothyroxine (LT4) ingestion, in doses that ensure a sustained state of hormonal balance. Many different factors may significantly influence the absorption of LT4, including: interval between the ingestion of the drug and the last meal, eating habits, and different functional and organic pathologies of the gastro-intestinal tract. The main purpose of this paper is to review and systematise the available literature on the subject of the influence of different malabsorption syndromes on the effectiveness of LT4 preparations. The need to use high LT4 doses in the substitutional treatment of hypothyroidism is often the very first sign of one of the pathologies that are connected with malabsorption syndrome, which might have been asymptomatic and undiagnosed previously. Patients who require more than 2 μg/kg body weight of LT4 per day, with constantly increased thyrotropin level, should be diagnosed with the suspicion of pseudomalabsorption or real absorption disorder. An LT4 absorption test, using high doses of LT4, may be useful in the diagnosis of pseudomalabsorption. After excluding non-compliance, the differential diagnosis should include such disorders as lactose intolerance, coeliac disease, atrophic gastritis, Helicobacter pylori infection, bowel resection, inflammatory bowel disease, and parasite infection. Where there is a diagnosis of lactose intolerance, both a low lactose diet and a lactose-free LT4 preparation should be administered to restore euthyroidism or make it possible to decrease the dose of the LT4 preparation. In coeliac disease, a gluten-free diet usually allows a normalisation of the need for LT4, as do eradication of the H. pylori infection or parasite colonisation. In cases of atrophic gastritis or inflammatory bowel disease, treating the underlying diseases and regaining the state of remission may improve the absorption of LT4. In patients after gastro-intestinal tract surgery, a dose of LT4 higher than that typically used is needed to restore euthyroidism.     

Role of matrix metalloproteinases in inflammatory bowel disease

Recent evidence demonstrates that the increased expression and activity of matrix metalloproteinases (MMPs) may contribute to intestinal tissue injury and inflammation in inflammatory bowel disease, and that MMP inhibition might be a new therapeutic approach to controlling inflammatory response. In addition, MMPs may play a crucial role in physiological and pathophysiological reactions such as leukocyte accumulation into inflamed tissue, cytokine production from inflammatory and epithelial cells, T lymphocyte homing to the intestine, wound healing and proliferation of epithelial cells, and intestinal innate immunity. This review focuses on recent progress in elucidating the biological and pathological roles of MMPs in inflammatory bowel disease.     

Adhesive Escherichia coli in inflammatory bowel disease and infective diarrhoea.

The clinical features of ulcerative colitis and Crohn''s disease are similar to those of infections of the bowel, although their cause is uncertain. Many bacteria that cause intestinal diseases adhere to the gut mucosa, and adhesion of pathogenic Escherichia coli is resistant to D-mannose. The adhesive properties of isolates of E coli were assessed by assay of adhesion to buccal epithelial cells with mannose added. The isolates were obtained from patients with inflammatory bowel diseases (50 with a relapse of ulcerative colitis, nine with ulcerative colitis in remission, 13 with Crohn''s disease, and 11 with infectious diarrhoea not due to E coli) and 22 controls. The median index of adhesion to buccal epithelial cells (the proportion of cells with more than 50 adherent bacteria) for E coli from patients with ulcerative colitis in relapse was significantly higher (43%) than that for controls (5%) and patients with infectious diarrhoea (14%). The index was not significantly different among isolates from patients with ulcerative colitis in relapse, Crohn''s disease (53%), and ulcerative colitis in remission (30%). If an index of adhesion of greater than 25% is taken as indicating an adhesive strain 86% of isolates of E coli from patients with inflammatory bowel disease were adhesive compared with 27% from patients with infective diarrhoea and none from controls. The adhesive properties of the isolates from patients with inflammatory bowel disease were similar to those of pathogenic intestinal E coli, raising the possibility that they may have a role in the pathogenesis of the condition; the smaller proportion of adhesive isolates in patients with infective diarrhoea due to other bacteria suggests that the organism may be of primary importance rather than arising secondarily.     

CT仿真结肠镜与腹部增强CT 在炎症性肠病诊断中的对比分析

目的:对比CT仿真结肠镜(CTC)与腹部增强CT在炎症性肠病诊断中的价值,为临床诊疗提供依据。方法:选取2015年1月到2016年1月我院收治的炎症性肠病患者60例为研究组,另选取非炎症性肠病患者60例为对照组,两组均30例患者接受CTC检查,30例患者接受腹部增强CT检查,对影像图片进行盲法阅读,将炎症性肠病的可信度分为5个等级进行评价,对6项影像学特征进行Logistic回归分析。结果:腹部增强CT对炎症性肠病诊断的准确率、敏感性、特异性分别为68.33%,59.09%,71.39%显著低于CTC的93.33%,95.01%、89.63%,比较差异具有统计学意义(P0.05);Logistic回归分析显示:结肠粘膜呈颗粒状、不光滑;肠壁强化并增厚;结肠袋消失对炎症性肠病具有预测作用;肠壁强化及增厚对炎症性肠病诊断敏感性较高,结肠粘膜呈颗粒状、不光滑联合结肠袋消失诊断炎症性肠病的特异性较高。结论:CTC对炎症性肠病具有较高的检出率,肠壁强化及增厚对炎症性肠病诊断的敏感性较高,结肠粘膜呈颗粒状、不光滑联合结肠袋消失诊断炎症性肠病特异性较高。     

Lower prevalence of Helicobacter pylori infection in patients with inflammatory bowel disease but not with chronic obstructive pulmonary disease - antibiotic use in the history does not play a significant role

BACKGROUND: Patients with inflammatory bowel disease have lower prevalence of Helicobacter pylori infection, but the exact reason for this is not yet clear. AIM: To examine whether the antibiotics frequently used in inflammatory bowel disease are responsible for the lower prevalence of H. pylori infection. Patients with chronic obstructive pulmonary disease on prolonged previous antibiotic therapy were used for comparison. METHODS: Presence/absence of H. pylori infection was detected by a (13)C-urea breath test in 133 patients with inflammatory bowel disease (82 ulcerative colitis, and 51 Crohn's disease) and compared with that of 135 patients with chronic obstructive pulmonary disease and with two age-matched control groups (200 patients each). Primary disease location, duration of disease and detailed analysis of previous and current medication (dose and duration of antibiotics, steroids, 5-aminosalicylic acid) were analysed in each cases. RESULTS: Seventeen of the 133 patients with inflammatory bowel disease [12.2% (10/82) of ulcerative colitis and 13.7% (7/51) of Crohn's disease] and 90/135 patients with chronic obstructive pulmonary disease (66.7%) were positive for H. pylori. A total of 78/200 (39%) for the inflammatory-bowel-disease-group-matched controls and 110/210 (55%) for the chronic-obstructive-pulmonary-disease-matched controls were positive for H. pylori. The history of any antibiotic or steroid therapy had no influence on H. pylori status of patients with inflammatory bowel disease. CONCLUSION: The prevalence of H. pylori compared to the age-matched controls is significantly lower in patients with inflammatory bowel disease but not in those with chronic obstructive pulmonary disease. Antibiotic use is not responsible for the lower prevalence of H. pylori infection in patients with inflammatory bowel disease.     

INTESTINAL OBSTRUCTION COMPLICATING ACUTE PERFORATIVE APPENDICITIS

Upon preoperative diagnosis of acute small bowel obstruction, without an obvious cause, acute perforative appendicitis must be considered. Reevaluation of the history and careful reexamination of the physical findings with that diagnosis in mind should be carried out. If appendiceal disease is likely, maximum antibiotic therapy must be begun immediately along with the administration of fluids, electrolytes and other corrective therapy. A mercury-weighted small bowel tube should be inserted and every effort made to advance it into the small bowel before operation. Operative treatment should be restricted to the least possible. A McBurney incision is best unless wider operation is indicated. If an abscess is present, drainage alone may be the procedure of choice. Severely distended and decompensated small bowel must be decompressed, for if not relieved it can be the cause of death in acute perforative appendicitis. Decompression may be accomplished either by small bowel intubation with continuous suction or by enterotomy and aspiration. If not relieved, small bowel distention will be the mechanism responsible for death in a large percentage of patients with acute perforative appendicitis.     

炎症性肠病动物模型的研究进展

克罗恩病和溃疡性结肠炎统称为炎症性肠病（IBD）,病因虽不明确,但对其发病机理已有了较多的了解。该病的发生是由于个体易感性、肠道菌群和粘膜免疫相互作用所致。炎症性肠病动物模型可通过化学性诱导、免疫学、遗传学等方法获得。三硝基苯磺酸与乙醇灌肠致炎法是目前最常用的方法,本文侧重概述介绍三硝基苯磺酸诱导的炎症性肠病的机制、模型、应用及优缺点,为疾病的研究、治疗和新药的开发提供指导。     

Pleuropulmonary amebiasis

Pleuropulmonary amebiasis may be manifest without diarrhea or dysentery.In obscure lesions of the right lower lung field, one should always consider pleuropulmonary amebiasis-especially with low grade fever and moderate leukocytosis. Abscess and empyema contents should be examined promptly microscopically or kept warm to preserve the motility of the trophozoites until satisfactory examination is possible. Conservative therapy will successfully manage most cases of pleuropulmonary amebiasis. If a thorough search fails to reveal Entameba histolytica, and the diagnosis is still entertained, a medical therapeutic trial is in order.     

Mortality in patients with and without colectomy admitted to hospital for ulcerative colitis and Crohn's disease: record linkage studies

Objective To compare mortality outcomes in the three years after elective colectomy, no colectomy, and emergency colectomy among people admitted to hospital for inflammatory bowel disease, to inform whether the threshold for elective colectomy in clinical practice is appropriate.Design Record linkage studies.Setting Oxford region (1968-99) and England (1998-2003).Participants 23 464 people with hospital stay for more than three days for inflammatory bowel disease, including 5480 who had colectomy.Main outcome measures Case fatality, relative survival, and standardised mortality ratios.Results In the Oxford region, three year mortality was lower after elective colectomy than after either no colectomy or emergency colectomy, although this was not significant. For England, mortality three years after elective colectomy for ulcerative colitis (3.7%) and Crohn''s disease (3.3%) was significantly lower than that after either admission without colectomy (13.6% and 10.1%; both P<0.001) or emergency colectomy (13.2% and 9.9%; P<0.001 for colitis and P<0.01 for Crohn''s disease). Three or more months after elective colectomy, mortality was similar to that in the general population. Adjustment for comorbidity did not affect the findings.Conclusions In England, the clinical threshold for elective colectomy in people with inflammatory bowel disease may be too high. Further research is now required to establish the threshold criteria and optimal timing of elective surgery for people with poorly controlled inflammatory bowel disease.     

Significant increase of interleukin 6 production in blood mononuclear leukocytes obtained from patients with active inflammatory bowel disease

In the present study, we compared the potency of interleukin 6 production in peripheral blood mononuclear leukocytes between paired patients with active stage and inactive stage of inflammatory bowel disease. Subjects included nine patients with ulcerative colitis, ten patients with Crohn's disease and sex-matched nine healthy volunteers. Mononuclear leukocytes were stimulated with concanavalin A for 24 h to induce interleukin 6 production. Interleukin 6 content in the culture medium was assayed by using specific ELISA and interleukin 6 dependent cell line MH-60. Interleukin 6 production was found to be significantly increased in mononuclear leukocytes from both active ulcerative colitis and Crohn's disease as compared to that from control subjects. There was no significant difference in interleukin 6 production between ulcerative colitis and Crohn's disease. The potency of interleukin 6 production was returned to the control level when the diseases became inactive. The present results, therefore, may indicate some important role of interleukin 6 in the pathogenesis of inflammatory bowel disease and also the potency of interleukin 6 production in mononuclear leukocytes can be an indicator of the activity of inflammatory bowel disease.     

Increased prevalence of CFTR mutations and variants and decreased chloride secretion in primary sclerosing cholangitis

Primary sclerosing cholangitis (PSC) and cystic fibrosis (CF) are both slowly progressive cholestatic liver diseases characterized by fibro-obliterative inflammation of the biliary tract. We hypothesized that dysfunction of the CF gene product, cystic fibrosis transmembrane conductance regulator (CFTR), may explain why a subset of patients with inflammatory bowel disease develop PSC. We prospectively evaluated CFTR genotype and phenotype in patients with PSC ( n=19) compared with patients with inflammatory bowel disease and no liver disease ( n=18), primary biliary cirrhosis ( n=17), CF ( n=81), and healthy controls ( n=51). Genetic analysis of the CFTR gene in PSC patients compared with disease controls (primary biliary cirrhosis and inflammatory bowel disease) demonstrated a significantly increased number of mutations/variants in the PSC group (37% vs 8.6% of disease controls, P=0.02). None of the PSC patients carried two mutations/variants. Of PSC patients, 89% carried the 1540G-variant-containing genotypes (resulting in decreased functional CFTR) compared with 57% of disease controls ( P=0.03). Only one of 19 PSC patients had neither a CFTR mutation nor the 1540G variant. CFTR chloride channel function assessed by nasal potential difference testing demonstrated a reduced median isoproterenol response of 14 mV in PSC patients compared with 19 mV in disease controls ( P=0.04) and 21 mV in healthy controls ( P=0.003). These data indicate that there is an increased prevalence of CFTR abnormalities in PSC as demonstrated by molecular and functional analyses and that these abnormalities may contribute to the development of PSC in a subset of patients with inflammatory bowel disease.     

Monochloramine induces acute and protracted colitis in the rat: response to pharmacological treatment

Monochloramine is a powerful oxidative molecule that is produced in inflammatory sites. We investigated the effect of intrarectally administered monochloramine (3.2 mg) in the rat. A single enema induced after 24 h an intense inflammatory reaction characterized by mucosal necrosis, submucosal edema, hemorrhage and colonic thickening, as well as induction of nitric oxide synthase and tumor necrosis factor and an increase in the interferon gamma/interleukin 4 ratio. The inflammatory response peaked 3-5 days after monochloramine administration and then followed a extended recovery phase. At 1 week there was substantial but incomplete mucosal repair, submucosal edema, neutrophil/macrophage infiltration and increased myeloperoxydase and alkaline phosphatase activities. Oxidative stress, as determined by malonyldialdehyde levels, was prominent only in the acute phase (3-5 days). Monochloramine colitis was amenable to pharmacological treatment with sulphasalazine or prednisolone, suggesting that it may be used as an experimental model of inflammatory bowel disease. In conclusion, monochloramine induces acute and protracted colonic inflammation in the rat. Locally produced monochloramine might contribute to the perpetuation of inflammatory bowel disease.     

Stress and the Gastrointestinal Tract IV. Modulation of intestinal inflammation by stress: basic mechanisms and clinical relevance

The stress response in a healthy organism is generally viewed as a warning and thus a protective reaction to a threat. However, the response may be deleterious if it is linked to an inflammatory stimulus or if it proceeds an inflammatory event. Prior stress enhances the response to an inflammatory stimulus by a mechanism that is independent of the release of hypothalamic corticotropin-releasing factor (CRF) or arginine vasopressin. Putative mechanisms include an increase in intestinal permeability as well as the release of the proinflammatory neuropeptide substance P. Stress may also reactivate previous inflammation when applied in conjunction with a small luminal stimulus. This reactivation involves increased permeability and requires the presence of T lymphocytes. Inflammatory mediators activate hypothalamic pathways, and a negative feedback loop, mediated by CRF release, has been proposed because animals with impaired hypothalamic CRF responses are more susceptible to inflammatory stimuli. Together, these experimental observations provide insights into the expression of inflammatory disorders in humans, including inflammatory bowel disease and postinfective irritable bowel syndrome.     

PLEUROPULMONARY AMEBIASIS

Pleuropulmonary amebiasis may be manifest without diarrhea or dysentery.In obscure lesions of the right lower lung field, one should always consider pleuropulmonary amebiasis—especially with low grade fever and moderate leukocytosis.Abscess and empyema contents should be examined promptly microscopically or kept warm to preserve the motility of the trophozoites until satisfactory examination is possible.Conservative therapy will successfully manage most cases of pleuropulmonary amebiasis.If a thorough search fails to reveal Entameba histolytica, and the diagnosis is still entertained, a medical therapeutic trial is in order.