Low molecular weight heparin (tinzaparin) vs. placebo in the treatment of mild to moderately active ulcerative colitis

Pentosan Polysulfate Sodium augments the therapeutic effect of 5-Aminosalicylic Acid in DSS colitis model; the role of IL-35 expression

Ulcerative colitis (UC) primarily affects the mucosa of the distal colon. Dysregulated immune response in genetically-prone persons is claimed to be responsible for chronic intestinal inflammation. This study aimed to explore the efficacy and the hematological effects of pentosan polysulfate sodium (PPS) in a dextran sulfate sodium (DSS)-induced colitis model. Forty C57BL/6 female mice were equally divided into five groups: control group, DSS-colitis group, DSS-colitis treated with 5-aminosalicylic acid, DSS-colitis treated with PPS, and DSS-colitis treated with both drugs. Disease activity index (DAI) and colon length were calculated. Colonic IL-6 and IL-35 levels were assayed by ELISA. IL-35 gene expression was evaluated by qRT-PCR. Colon tissue samples were examined by H&E stain and immunohistochemistry (IHC) of Ki67. The colitis group subjected to combined treatment showed the best outcome with significant improvement of DAI and increased colon length. Colonic IL-6 was significantly lower in both PPS- and combination-treated groups accompanied by a significantly higher IL-35 level and its EBI3 subunit mRNA expression. However, the PPS-treated colitis group showed higher gene expression of IL-35 EBI3 subunit by 1.5-fold compared with the combined group. The colon mucosa and crypts were significantly preserved in mice treated with both drugs with the best Ki67 positive cell density. PPS is a safe and promising drug in the treatment of UC as it exerted the best positive effect on the anti-inflammatory IL-35 level and gene expression. However, superior improvement of DAI was seen when PPS was added to ASA with a greater mucosal proliferation and repair.

The Inflammatory Bowel Disease Questionnaire in Randomized Controlled Trials of Treatment for Ulcerative Colitis: Systematic Review and Meta-Analysis

Purpose

The 32-item Inflammatory Bowel Disease Questionnaire (IBDQ-32) is the most frequently used instrument to capture disease-specific quality of life in randomized clinical trials for ulcerative colitis. This review and meta-analysis provides the first synthesis of evidence regarding the sensitivity of IBDQ-32 total and domain scores to treatment efficacy.

Methods

A systematic literature search and risk-of-bias assessment yielded 14 articles that were included in the primary analysis. Treatments were categorized as efficacious if they met the primary efficacy endpoint (which was not the IBDQ-32); otherwise they were categorized as non-efficacious. A continuous measure of treatment efficacy was calculated for each primary efficacy endpoint. Meta-analysis using random-effects models compared standardized mean differences in IBDQ-32 total and domain change scores between target dose and control arms. Meta-regression compared the association between treatment efficacy and these outcomes.

Results

Studies with efficacious treatments showed larger mean improvements relative to controls in IBDQ-32 total scores and all 4 domains (Hedges' g range: 0.49 to 0.67; P<0.001 for all). At the same time, patients in studies with non-efficacious treatments showed small and nonsignificant improvements in these outcomes relative to controls (Hedges' g range: 0.05 to 0.23; P>0.09 for all). Meta-regression models showed that the magnitude of treatment efficacy was a positive predictor of these same IBDQ-32 outcomes.

Conclusions

These analyses found that IBDQ-32 scores are sensitive to treatment. The results provided here support the use of the IBDQ-32 to capture treatment benefits on quality of life for patients with ulcerative colitis.

Therapeutic Potential of Enoxaparin in Lichen Planus: Exploring Reasons for Inconsistent Reports

Lichen planus (LP) is an uncommon mucocutaneous inflammatory condition, that is immunologically mediated, typically pruritic and often recurs. The currently advocated therapies are either not highly effective or associated with severe side effects. Enoxaparin, a widely used anticoagulant, is composed of both anticoagulant and non-anticoagulant fragments. Enoxaparin is reported to have anti-inflammatory properties and it was found to be effective in LP. However, the results from clinical studies have varied substantially and, therefore, the clinical role of enoxaparin in LP remains uncertain. This review focuses on potential reasons for the reported inconsistent outcomes, as well as proposing solutions; these include identifying batch-to-batch inconsistency in the composition of enoxaparin. The potential therapeutic value of enoxaparin in LP must be explored using well-designed clinical trials, combined with experimental studies that focus on identifying the anti-inflammatory fragments of enoxaparin and elucidating the mechanism of action of these non-anticoagulant fragments.

Azathioprine for refractory ulcerative proctitis: A retrospective multicenter study

BACKGROUND

Efficacy of azathioprine (AZA) in refractory ulcerative proctitis (UP) is unknown.

METHODS

All patients treated with AZA for refractory UP in three referral centers between 2002 and 2012 were included. "Treatment success" in the long-term was defined as the absence of colectomy during follow-up, no need for anti-TNF during follow-up, no ongoing systemic steroids use, no adverse event leading to AZA withdrawal, and clinically quiescent disease at last follow-up.

RESULTS

Of the 1279 adult patients with ulcerative colitis, 25 patients were treated with AZA for refractory UP (median disease duration 4.9 years). Of these, 4 had no short-term clinical assessment. Of the remaining 21, 4 were primary non responders to AZA, 7 discontinued AZA for adverse events and 10 showed clinical improvement. At the long-term assessment at last follow up after a median of 46 months, 5 patients had treatment success and were still on AZA treatment, the remaining 20 were treatment failures. Of these, 5 discontinued AZA for adverse events and 15 were treated with infliximab (clinical response in 11 patients, primary non-response in one patient, and 3 underwent colectomy).

CONCLUSION

AZA may be efficacious in maintaining clinical response in one-fifth of patients with refractory UP in a real-life setting.

Non-anticoagulant effects of low molecular weight heparins in inflammatory disorders: A review

Low molecular weight heparins (LMWHs) are produced by chemical or enzymatic depolymerization of unfractionated heparin (UFH). Besides their well-known anticoagulant effects, LMWHs have also been reported to exhibit numerous anti-inflammatory properties. Previous studies have, however, shown that different production processes result in unique structural characteristics of LMWHs. The structural variations may help explain the different therapeutic spectrums in disease treatment for non-anticoagulant effects. In the present review, we summarize major advances in understanding and exploiting the anti-inflammatory disorder activities of LMWHs, based on mechanistic studies, preclinical experiments and clinical trials. We highlight differences in these activities of commercially available LMWHs produced using different manufacturing processes. We stress the importance of structure-activity relationship (SAR) studies on the non-anticoagulant effects of LMWHs and discuss strategies for exploring new clinical indications.

Managing acute severe ulcerative colitis in the hosptialised setting

Ulcerative colitis affects approximately 146 000 people in the UK and is the most common form of inflammatory bowel disease. The majority of patients will have uncomplicated disease, but around 1 in 10 patients will develop acute severe colitis. Despite modern medical management, colectomy rates of 27% and mortality rates of 1% are still reported. Good supportive care and intravenous corticosteroids remain the mainstay of treatment, but up to one-third of patents will not respond. The Travis criteria allow early recognition of those patients failing to improve by day 3, allowing timely planning of medical rescue therapy or surgery. Rescue therapy with either infliximab or ciclosporin appears equally efficacious. Patients naive to thiopurines seem to have better colectomy-free survival rates following rescue therapy than those previously exposed. We review the published evidence behind the conventional management of acute severe ulcerative colitis.

Heparins in ulcerative colitis: proposed mechanisms of action and potential reasons for inconsistent clinical outcomes

Current drug therapies for ulcerative colitis (UC) are not completely effective in managing moderate-to-severe UC and approximately 20% of patients with severe UC require surgical interventions. Heparins, polydisperse mixtures of non-anticoagulant and anticoagulant oligosaccharides, are widely used as anticoagulants. However, heparins are also reported to have anti-inflammatory properties. Unfractionated heparin was initially used in patients with UC for the treatment of rectal microthrombi. Surprisingly, it was found to be effective in reducing UC-associated symptoms. Since then, several pre-clinical and clinical studies have reported promising outcomes of heparins in UC. In contrast, some controlled clinical trials demonstrated no or only limited benefits, thus the potential of heparins for the treatment of UC remains uncertain. This review discusses potential mechanisms of action of heparins, as well as proposed reasons for their contradictory clinical effectiveness in the treatment of UC.

Unfractionated or low-molecular weight heparin for induction of remission in ulcerative colitis

BACKGROUND

There are a limited number of treatment options for patients with ulcerative colitis (UC). An increased risk of thrombosis in UC coupled with an observation that UC patients being treated with anticoagulant therapy for thrombotic events had an improvement in their bowel symptoms led to trials examining the use of unfractionated heparin (UFH) and low molecular weight heparins (LMWH) in patients with active UC.

OBJECTIVES

To review randomized trials examining the efficacy of unfractionated heparin (UFH) or low molecular weight heparins (LMWH) for remission induction in patients with ulcerative colitis.

SEARCH METHODS

We searched MEDLINE, EMBASE, CENTRAL, and the Cochrane IBD/FBD group specialized trials register up to June 2014. We also searched review papers on ulcerative colitis and references from identified papers in an effort to identify additional randomized trials studying UFH or LMWH use in patients with ulcerative colitis. We searched abstracts from major gastroenterological meetings to identify research published in abstract form.

SELECTION CRITERIA

Randomized controlled trials comparing UFH or LMWH to placebo or a control therapy for induction of remission in ulcerative colitis were included. Studies published in abstract form only were included if the authors could be contacted for further information.

DATA COLLECTION AND ANALYSIS

A data extraction form was developed and used to extract data from included studies. Two authors independently extracted data. Any disagreements were resolved by consensus. The Cochrane Risk of Bias tool was used to assess study quality. Data were analyzed on an intention-to-treat basis. The primary outcome was induction of remission, as defined by the studies. Secondary outcomes measures included: endoscopic remission as defined by the authors; clinical, histological or endoscopic improvement as defined by the authors; the occurrence of adverse events; the occurrence of bleeding; and improvements in quality of life as measured by a validated instrument. We calculated the risk ratio (RR) and corresponding 95% confidence interval for dichotomous outcomes. Data were combined for analysis if they assessed the same treatments (UFH or LMWH versus placebo or other therapy). The overall quality of the evidence supporting the outcomes was evaluated using the GRADE criteria.

MAIN RESULTS

Five studies were eligible for inclusion (329 patients). Three studies (270 patients) compared low molecular weight heparin to placebo, one study (34 patients) compared LMWH in addition to standard therapy, and one study (25 patients) compared UFH to corticosteroids. The study comparing UFH to corticosteroids was rated at high risk of bias due to a single-blind design. The study that compared the addition of LMWH to standard therapy to standard therapy alone was rated at high risk of bias due to open-label design. The other three studies were rated as low risk of bias. LMWH administered subcutaneously showed no benefit over placebo for any outcome, including clinical remission (very low quality of evidence), and clinical, endoscopic, or histological improvement. High dose LMWH administered via an extended colon-release tablet demonstrated benefit over placebo for clinical remission (RR 1.39; 95% CI 1.09 to 1.77 ; P = 0.008; very low quality of evidence), clinical improvement (RR 1.28; 95% CI 1.06 to 1.55; P = 0.01; very low quality of evidence), and endoscopic improvement (RR 1.21; 95% CI 1.00 to 1.47 ; P = 0.05) but not endoscopic remission or histologic improvement. LMWH was not beneficial when added to standard therapy for clinical remission, clinical improvement, endoscopic remission or endoscopic improvement. LMWH was well-tolerated but provided no significant benefit for quality of life. One study examining UFH versus corticosteroids for the treatment of severe UC demonstrated the inferiority of UFH for clinical improvement. More patients assigned to UFH had rectal hemorrhage as an adverse event.

AUTHORS' CONCLUSIONS

There is evidence to suggest that LMWH may be effective for the treatment of active UC. When administered by extended colon-release tablets, LMWH was more effective than placebo for treating outpatients with mild to moderate disease. This benefit needs to be confirmed by further randomized controlled studies. The same benefits were not seen when LMWH was administered subcutaneously at lower doses. There is no evidence to support the use of UFH for the treatment of active UC. A further trial of UFH in patients with mild disease may also be justified. Any benefit found would need to be weighed against a possible increased risk of rectal bleeding in patients with active UC.

Orally Administered Enoxaparin Ameliorates Acute Colitis by Reducing Macrophage-Associated Inflammatory Responses

Inflammatory bowel diseases, such as ulcerative colitis, cause significant morbidity and decreased quality of life. The currently available treatments are not effective in all patients, can be expensive and have potential to cause severe side effects. This prompts the need for new treatment modalities. Enoxaparin, a widely used antithrombotic agent, is reported to possess anti-inflammatory properties and therefore we evaluated its therapeutic potential in a mouse model of colitis. Acute colitis was induced in male C57BL/6 mice by administration of dextran sulfate sodium (DSS). Mice were treated once daily with enoxaparin via oral or intraperitoneal administration and monitored for colitis activities. On termination (day 8), colons were collected for macroscopic evaluation and cytokine measurement, and processed for histology and immunohistochemistry. Oral but not intraperitoneal administration of enoxaparin significantly ameliorated DSS-induced colitis. Oral enoxaparin-treated mice retained their body weight and displayed less diarrhea and fecal blood loss compared to the untreated colitis group. Colon weight in enoxaparin-treated mice was significantly lower, indicating reduced inflammation and edema. Histological examination of untreated colitis mice showed a massive loss of crypt architecture and goblet cells, infiltration of immune cells and the presence of edema, while all aspects of this pathology were alleviated by oral enoxaparin. Reduced number of macrophages in the colon of oral enoxaparin-treated mice was accompanied by decreased levels of pro-inflammatory cytokines. Oral enoxaparin significantly reduces the inflammatory pathology associated with DSS-induced colitis in mice and could therefore represent a novel therapeutic option for the management of ulcerative colitis.

Anti-Inflammatory Effects of Heparin and Its Derivatives: A Systematic Review

Background. Heparin, used clinically as an anticoagulant, also has anti-inflammatory properties. The purpose of this systematic review was to provide a comprehensive review regarding the efficacy and safety of heparin and its derivatives as anti-inflammatory agents. Methods. We searched the following databases up to March 2012: Pub Med, Scopus, Web of Science, Ovid, Elsevier, and Google Scholar using combination of Mesh terms. Randomized Clinical Trials (RCTs) and trials with quasi-experimental design in clinical setting published in English were included. Quality assessments of RCTs were performed using Jadad score and Consolidated Standards of Reporting Trials (CONSORT) checklist. Results. A total of 280 relevant studies were reviewed and 57 studies met the inclusion criteria. Among them 48 studies were RCTs. About 65% of articles had score of 3 and higher according to Jadad score. Twelve studies had a quality score > 40% according to CONSORT items. Asthma (n = 7), inflammatory bowel disease (n = 5), cardiopulmonary bypass (n = 8), and cataract surgery (n = 6) were the most studied disease condition. Forty studies use unfractionated heparin (UFH) for intervention; the remaining studies use low molecular weight heparin (LMWH). Conclusion. Despite the conflicting results, heparin seems to be a safe and effective anti-inflammatory agent; although it is shown that heparin can decrease the level of inflammatory biomarkers and improves patient conditions, still more data from larger rigorously designed studies are needed to support use of heparin as an anti-inflammatory agent in clinical setting. However, because of the association between inflammation, atherogenesis, thrombogenesis, and cell proliferation, heparin and related compounds with pleiotropic effects may have greater therapeutic efficacy than compounds acting against a single target.

Rivaroxaban Induces Mucosal Healing in a Rat Model of Trinitrobenzene Sulfonic Acid-Induced Colitis

OBJECTIVE

This study was designed to identify the effect of rivaroxaban, a direct factor Xa inhibitor, on trinitrobenzene sulfonic acid (TNBS)-induced colitis in rats.

MATERIALS AND METHODS

Twenty-four female Wistar rats were divided into 4 groups of 6 each. Group 1 received TNBS + rivaroxaban, group 2 received TNBS + methylprednisolone, group 3 received TNBS and group 4 received a saline enema. Colitis was induced in the rats by the intracolonic administration of TNBS. Rivaroxaban and methylprednisolone were given by oral gavage daily for 7 days. The rats were killed 7 days after the induction of colitis.

RESULTS

Rivaroxaban and methylprednisolone significantly reduced gross damage and histopathological scores. Rivaroxaban was more effective than methylprednisolone in terms of microscopic mucosal healing. Rivaroxaban attenuated the accumulation of malonyldialdehyde (MDA) and transforming growth-factor β1 (TGF-β1) and the activities of myeloperoxidase (MPO), matrix metalloproteinase-3 and tissue inhibitor of metalloproteinases-1. Methylprednisolone reduced only the activity of MPO and the accumulation of MDA and TGF-β1. Superoxide dismutase activity showed a restoration to normal levels after rivaroxaban and methylprednisolone administration.

CONCLUSIONS

Rivaroxaban showed a therapeutic effect in the TNBS model of experimental colitis, and it seemed to be at least as effective as methylprednisolone. This effect may be brought about by the inhibition of oxidative stress and metalloproteinase activity associated with tissue injury and remodeling.

Consensus statements on the risk, prevention, and treatment of venous thromboembolism in inflammatory bowel disease: Canadian Association of Gastroenterology

BACKGROUND & AIMS

Guidelines for the management of venous thromboembolism (VTE) from the American College of Chest Physicians do not address patients with inflammatory bowel disease (IBD), a group with a high risk of both VTE and gastrointestinal bleeding. We present recommendations for the prevention and treatment of VTE in patients with IBD.

METHODS

A systematic literature search was performed to identify studies on VTE in IBD. The quality of evidence and strength of recommendations were rated according to the Grading of Recommendation Assessment, Development, and Evaluation (GRADE) approach. Statements were developed through an iterative online platform, then finalized and voted on by a working group of adult and pediatric gastroenterologists and thrombosis specialists.

RESULTS

IBD patients have an approximately 3-fold higher risk of VTE compared with individuals without IBD, and disease flares further increase this risk. Anticoagulant thromboprophylaxis is recommended for IBD patients who are hospitalized with IBD flares without active bleeding and is suggested when bleeding is nonsevere. Anticoagulant thromboprophylaxis is suggested during moderate-severe IBD flares in outpatients with a history of VTE provoked by an IBD flare or an unprovoked VTE, but not otherwise. The recommended duration of anticoagulation after a first VTE is based on the presence of provoking factors. Specific suggestions are made for the prevention and treatment of VTE in pediatric and pregnant IBD patients.

CONCLUSIONS

Using the American College of Chest Physicians' guidelines as a foundation, we have integrated evidence from IBD studies to develop specific recommendations for the management of VTE in this high-risk population.

Inflammatory bowel disease: epidemiology, pathology and risk factors for hypercoagulability

Hypercoagulability observed in patients with inflammatory bowel diseases (IBD) may lead to thromboembolic events (TE), which affect the venous and arterial systems alike and are an important factor in patients' morbidity and mortality. The risk of TE in IBD patients has been demonstrated to be approximately three-fold higher as compared to the general population. The pathogenesis of thrombosis in IBD patients is multifactorial and not fully explained. The most commonly listed factors include genetic and immune abnormalities, disequilibrium between procoagulant and anticoagulant factors, although recently, the role of endothelial damage as an IBD-triggering factor is underlined. Several studies report that the levels of some coagulation enzymes, including fibrinogen, factors V, VII, VIII, active factor XI, tissue factor, prothrombin fragment 1 + 2 and the thrombin-antithrombin complex, are altered in IBD patients. It has been demonstrated that there is a significant decrease of tissue plasminogen activator level, a marked increase of plasminogen activator inhibitor type 1 and thrombin-activable fibrinolysis inhibitor, a significantly lower level of antithrombin III and tissue factor pathway inhibitor. IBD patients have been also observed to produce an increased amount of various anticoagulant antibodies. Hyperhomocysteinemia, which is a potential risk factor for TE was also observed in some IBD patients. Further studies are necessary to assess the role of coagulation abnormalities in IBD etiology and to determine indications for thromboprophylactic treatment in patients at high risk of developing TE.

Risk factors, morbidity, and treatment of thrombosis in children and young adults with active inflammatory bowel disease

OBJECTIVES

Pediatric inpatients with inflammatory bowel disease (IBD) are rarely considered for thromboprophylaxis because of concerns about safety and underappreciation of thrombotic risk. We characterized thromboembolism (TE) in children and young adults with inflammatory bowel disease (IBD) at a single tertiary care hospital.

METHODS

We performed a retrospective review of an inpatient billing database for all IBD admissions with colonic involvement and an anticoagulation database for thrombotic complications from 2006 to 2011.

RESULTS

Of 532 patients admitted with IBD with colonic involvement, 10 (1.9%) had TE (9 venous, 1 arterial), 2 of whom had recurrent thrombosis. Many of the events resulted in considerable morbidity, including 4 cerebrovascular events and 2 pulmonary emboli. Established risk factors in IBD colitis inpatients with TE included: indwelling catheter (4/10), first-degree family member with TE (2/10), hereditary thrombophilia (3/10), smoking (1/10), oral contraceptive (1/5 females), and thalidomide (1/10). Additionally, most (8/10) patients had acquired thrombophilia, mostly elevation of factor VIII and anticardiolipin antibodies. Patients with IBD and TE received therapeutic anticoagulation without significantly increased bleeding. Thrombus resolution was documented in 7 cases, persistence in 2 cases and recurrence in 2 cases.

CONCLUSIONS

Pediatric inpatients hospitalized with IBD with colonic involvement have increased risk of TE, including complications of pulmonary embolism, recurrence, persistence, and indefinite long-term anticoagulation. Therapeutic anticoagulation in patients with IBD with active colitis appears safe. We identified both inherited thrombophilias and acquired risk factors in patients with IBD and TE. We presently use risk stratification and recommend prophylactic anticoagulation in high-risk patients.

Prevention of venous thromboembolism in hospitalized patients with inflammatory bowel disease

Venous thromboembolism is a relatively common and potentially serious complication in inpatients with inflammatory bowel disease (IBD). There are a number of pathophysiologic mechanisms for venous thromboembolism that are specific to patients with IBD that may be active. The use of anticoagulants for prophylaxis against venous thromboembolism in hospitalized patients with IBD needs to be balanced against the potential for worsening of rectal bleeding. Evidence from randomized trials suggests that heparin and low-molecular weight heparin are generally safe to use in patients with active IBD, and a number of guidelines support their use for thromboprophylaxis in this patient population.

Nadroparin sodium activates Nrf2/HO-1 pathway in acetic acid-induced colitis in rats

Effects of nadroparin sodium, a low molecular weight heparin, in colitis was investigated by analyzing proteins implicated in nuclear factor E2-related factor-2/heme oxygenase-1 (Nrf2/HO-1) and nuclear factor kappa B (NF-κB) pathways. Twenty-eight rats were used. Colitis was induced by acetic acid (AA). Nadroparin sodium was given to prevention and treatment groups in addition to AA. Colitis was assessed histologically and levels of proteins were analyzed with Western blot. Nadroparin not only prevented and ameliorated the AA-induced colitis histopathologically but also decreased expression of colon NF-κB, activator protein-1, cyclooxygenase-2, tumor necrosis factor-alpha, and IL-6, which were significantly increased in group AA compared to control. The accumulation of Nrf2 in nuclear fraction and HO-1 found low in group AA was increased with nadroparin (p < 0.05). The mean malondialdehyde level increased with AA and was decreased significantly with nadroparin prevention and treatment (p < 0.001). Nadroparin sodium has both protective and therapeutic effects against colonic inflammation via exerting anti-oxidative and anti-inflammatory effects by modulating Nrf2/HO-1 and NF-κB pathways.

Heparanase enzyme in chronic inflammatory bowel disease and colon cancer

Heparanase is the sole mammalian endoglycosidase that cleaves heparan sulfate, the key polysaccharide of the extracellular matrix and basement membranes. Enzymatic cleavage of heparan sulfate profoundly affects a variety of physiological and pathological processes, including morphogenesis, neovascularization, inflammation, and tumorigenesis. Critical involvement of heparanase in colorectal tumor progression and metastatic spread is widely documented; however, until recently a role for heparanase in the initiation of colon carcinoma remained underappreciated. Interestingly, the emerging data that link heparanase to chronic inflammatory bowel conditions, also suggest contribution of the enzyme to colonic tumor initiation, at least in the setting of colitis-associated cancer. Highly coordinated interplay between intestinal heparanase and immune cells (i.e., macrophages) preserves chronic inflammatory conditions and creates a tumor-promoting microenvironment. Here we review the action of heparanase in colon tumorigenesis and discuss recent findings, pointing to a role for heparanase in sustaining immune cell-epithelial crosstalk that underlies intestinal inflammation and the associated cancer.

Inflammatory bowel disease and thrombosis

Inflammatory Bowel Disease (IBD) is a group of chronic and relapsing inflammatory disorders of the gastrointestinalsystem. In these cases, findings are detected in extraintestinal systems also. There is a tendency for thrombotic eventsin IBD, as in the other inflammatory processes. The pathogenesis of this thrombotic tendency is multidimensional,including lack of natural anticoagulants, prothrombotic media induced via the inflammatory process, long-termsedentary life style, steroid use, surgery, and catheter placement. The aim of this review was to highlight the positiverelationship between IBD and thrombotic events, and the proper treatment of at-risk patients.

Unfractionated or low molecular weight heparin for induction of remission in ulcerative colitis: a Cochrane inflammatory bowel disease and functional bowel disorders systematic review of randomized trials

BACKGROUND

We aimed to systematically review the efficacy of unfractionated heparin (UFH) or low molecular weight heparins (LMWH) for remission induction in patients with ulcerative colitis (UC).

METHODS

A literature search to April 2011 was performed to identify all randomized trials studying UFH or LMWH use in patients with UC. The Cochrane Risk of Bias Tool was used to assess study quality.

RESULTS

LMWH administered subcutaneously showed no benefit over placebo for any outcome, including clinical remission, and clinical, endoscopic, or histological improvement. High-dose LMWH administered via an extended colon-release tablet demonstrated benefit over placebo for clinical remission (odds ratio [OR] 2.73; 95% confidence interval [CI] 1.32-5.67; P = 0.007), clinical improvement (OR 2.99; 95% CI 1.30-6.87; P = 0.01), and endoscopic improvement (OR 2.25; 95% CI 1.01-5.01; P = 0.05) but not endoscopic remission or histologic improvement. LMWH was not beneficial when added to standard therapy for clinical remission, clinical improvement, endoscopic remission, or endoscopic improvement. One study examining UFH versus corticosteroids for the treatment of severe UC demonstrated the inferiority of UFH for clinical improvement. More patients assigned to UFH had rectal hemorrhage as an adverse event.

CONCLUSIONS

LMWH administered by extended colon-release tablets may be effective for the treatment of active UC. This benefit needs to be confirmed by further randomized controlled studies. The same benefits were not seen when LMWH was administered subcutaneously at lower doses. There is no evidence to support the use of UFH for the treatment of active UC.

Tissue factor-dependent chemokine production aggravates experimental colitis

Tissue factor (TF) is traditionally known as the initiator of blood coagulation, but TF also plays an important role in inflammatory processes. Considering the pivotal role of coagulation in inflammatory bowel disease, we assessed whether genetic ablation of TF limits experimental colitis. To this end, wild-type and TF-deficient (TFlow) mice were treated with 1.5% dextran sulfate sodium (DSS) for 7 d, and effects on disease severity, cytokine production and leukocyte recruitment were examined. Clinical and histological parameters showed that the severity of colitis was reduced in both heterozygous and homozygous TFlow mice compared with controls. Most notably, edema, granulocyte numbers at the site of inflammation and cytokine levels were reduced in TFlow mice. Although anticoagulant treatment with dalteparin of wild-type mice reduced local fibrin production and cytokine levels to a similar extent as in TFlow mice, it did not affect clinical and histological parameters of experimental colitis. Mechanistic studies revealed that TF expression did not influence the intrinsic capacity of granulocytes to migrate. Instead, TF enhanced granulocyte migration into the colon by inducing high levels of the granulocyte chemoattractant keratinocyte-derived chemokine (KC). Taken together, our data indicate that TF plays a detrimental role in experimental colitis by signal transduction-dependent KC production in colon epithelial cells, thereby provoking granulocyte influx with subsequent inflammation and organ damage.

Haemostatic system in inflammatory bowel diseases: New players in gut inflammation

Inflammation and coagulation constantly influence each other and are constantly in balance. Emerging evidence supports this statement in acute inflammatory diseases, such as sepsis, but it also seems to be very important in chronic inflammatory settings, such as inflammatory bowel disease (IBD). Patients with Crohn’s disease and ulcerative colitis have an increased risk of thromboembolic events, and several abnormalities concerning coagulation components occur in the endothelial cells of intestinal vessels, where most severe inflammatory abnormalities occur. The aims of this review are to update and classify the type of coagulation system abnormalities in IBD, and analyze the strict and delicate balance between coagulation and inflammation at the mucosal level. Recent studies on possible therapeutic applications arising from investigations on coagulation abnormalities associated with IBD pathogenesis will also be briefly presented and critically reviewed.

Thrombosis and inflammatory bowel disease: a call for improved awareness and prevention

Thrombotic complications in patients with inflammatory bowel disease (IBD) are common and require improved awareness and prevention. In this review the interface between IBD and thrombosis is discussed, with emphasis on risk assessment and data to aid clinical decision making. Thromboembolic complications are 3-fold more likely in IBD patients than controls and the relative risk exceeds 15 during disease flares. Improved assessment of thrombosis risk for an individual patient includes thorough personal and family history and awareness of prothrombotic medications and lifestyle choices. Patients with the highest risk of thrombosis are those with active colonic disease, personal or strong family history of thrombosis, and those with significant acquired risk factors. Combined risk factors or hospitalization should prompt mechanical thromboprophylaxis. Indications for prophylactic anticoagulation are not defined currently by clinical studies, especially in pediatric patients, although some groups now advocate prophylactic anticoagulation for all hospitalized IBD patients and even some outpatients with disease flares. Thrombosis management requires a multidisciplinary therapeutic approach to balance anticoagulation and bleeding risk. While bleeding may occur with anticoagulation in IBD, data and experience indicate that therapeutic heparin is safe and bleeding manifestations can be managed supportively in most patients. Until prospective trials of prophylactic anticoagulation are published, management of thrombotic risk and prophylaxis in IBD will remain a clinical challenge.

Unfractionated or low-molecular weight heparin for induction of remission in ulcerative colitis

BACKGROUND

There are a limited number of treatment options for patients with ulcerative colitis (UC). An increased risk of thrombosis in UC coupled with an observation that UC patients being treated with anticoagulant therapy for thrombotic events had an improvement in their bowel symptoms led to trials examining the use of unfractionated heparin (UFH) and low molecular weight heparins (LMWH) in patients with active UC.

OBJECTIVES

To review randomized trials examining the efficacy of unfractionated heparin (UFH) or low molecular weight heparins (LMWH) for remission induction in patients with ulcerative colitis.

SEARCH STRATEGY

The MEDLINE (PUBMED), and EMBASE databases, The Cochrane Central Register of Controlled Trials, the Cochrane IBD/FBD group specialized trials register, review papers on ulcerative colitis, and references from identified papers were searched up to June 2010 in an effort to identify all randomized trials studying UFH or LMWH use in patients with ulcerative colitis. Abstracts from major gastroenterological meetings were searched to identify research published in abstract form only.

SELECTION CRITERIA

Each author independently reviewed potentially relevant trials to determine their eligibility for inclusion based on the criteria identified above. The Cochrane Risk of Bias tool was used to assess study quality. Studies published in abstract form only were included if the authors could be contacted for further information.

DATA COLLECTION AND ANALYSIS

A data extraction form was developed and used to extract data from included studies. At least 2 authors independently extracted data. Any disagreements were resolved by consensus. Data were analyzed on an intention-to-treat basis. The primary outcome was induction of remission, as defined by the studies. Data were combined for analysis if they assessed the same treatments (UFH or LMWH versus placebo or other therapy).

MAIN RESULTS

LMWH administered subcutaneously showed no benefit over placebo for any outcome, including clinical remission, and clinical, endoscopic, or histological improvement. High dose LMWH administered via an extended colon-release tablet demonstrated benefit over placebo for clinical remission (OR 2.73; 95% CI 1.32 to 5.67; P = 0.007), clinical improvement (OR 2.99; 95% CI 1.30 to 6.87; P = 0.01), and endoscopic improvement (OR 2.25; 95%CI 1.01 to 5.01; P = 0.05) but not endoscopic remission or histologic improvement. LMWH was not beneficial when added to standard therapy for clinical remission, clinical improvement, endoscopic remission or endoscopic improvement. LMWH was well-tolerated but provided no significant benefit for quality of life. One study examining UFH versus corticosteroids for the treatment of severe UC demonstrated the inferiority of UFH for clinical improvement. More patients assigned to UFH had rectal hemorrhage as an adverse event.

AUTHORS' CONCLUSIONS

There is evidence to suggest that LMWH may be effective for the treatment of active UC. When administered by extended colon-release tablets, LMWH was more effective than placebo for treating outpatients with mild to moderate disease. This benefit needs to be confirmed by further randomized controlled studies. The same benefits were not seen when LMWH was administered subcutaneously at lower doses. There is no evidence to support the use of UFH for the treatment of active UC. A further trial of UFH in patients with mild disease may also be justified. Any benefit found would need to be weighed against a possible increased risk of rectal bleeding in patients with active UC.

Infliximab for refractory ulcerative proctitis

BACKGROUND

Efficacy of infliximab in treating ulcerative proctitis remains unknown.

AIM

To evaluate the clinical, biological and endoscopic efficacy of infliximab therapy in refractory proctitis.

METHODS

The charts of 420 patients treated with infliximab for ulcerative colitis were reviewed. Thirteen patients were treated with infliximab for refractory ulcerative proctitis in six referral centres between 2005 and 2009.

RESULTS

Following infliximab therapy induction, 9/13 patients (69%) had a complete response (defined as absence of diarrhoea and blood), 2/13 (15%) had a partial response and 2/13 (15%) were primary nonresponders. The median follow-up was 17 months (range, 3-48). Among the 11 patients with clinical response after infliximab induction therapy, 9 (82%) patients maintained response at last follow-up. Disappearance of rectal disorders was observed in all nine patients who maintained clinical response at last follow-up. Following infliximab induction therapy, the mean CRP level fell from 12.8 mg/L to 4.7 mg/L. Endoscopic evaluation was performed before and after infliximab in seven patients, showing an improvement in mucosal lesions in four patients, persistent mild endoscopic activity in two patients and no improvement in one patient. One patient underwent proctocolectomy.

CONCLUSION

Infliximab therapy seems to be effective in inducing and maintaining a clinical response in refractory ulcerative proctitis.

Clinical trial: oral colon-release parnaparin sodium tablets (CB-01-05 MMX) for active left-sided ulcerative colitis

BACKGROUND

The administration of parnaparin sodium as oral colon-release tablets (CB-01-05 MMX) has been proposed as a novel approach for the treatment of ulcerative colitis (UC).

AIM

To assess the efficacy and the tolerability of 8 weeks' oral daily administration of 210 mg of parnaparin sodium compared with placebo in subjects treated with stable-doses of oral aminosalicylates.

METHODS

This multicenter, randomized, double-blind proof of concept trial compared the efficacy of CB-01-05 MMX 210 mg tablets to placebo in 141 subjects with mild to moderately active left-sided UC treated with stable-doses of aminosalicylates. The efficacy was assessed by clinical activity index (CAI), endoscopic index (EI) and histological score (HS).

RESULTS

A total of 121 subjects (61 in test group and 60 in control group) formed the per protocol (PP) population. After 8 weeks of treatment, clinical remission was achieved in 83.6% of the CB-01-05 MMX group, and in 63.3% in the comparator group (P = 0.011). This effect was also significantly evident in the test group at week 4 (P = 0.028). A significant difference was also detected in rectal bleeding, (disappeared respectively in 75.4% and 55.0%; P = 0.018), and in mucosal friability (recovered respectively in 80.3% and in 56.7%; P = 0.005).

CONCLUSIONS

CB-01-05 MMX was safe and significantly effective in treating subjects with mild-to-moderate left-sided UC treated with stable-doses of aminosalicylates.

Hospitalized ulcerative colitis patients have an elevated risk of thromboembolic events

AIM: To compare thromboembolism rates between hospitalized patients with a diagnosis of ulcerative colitis and other hospitalized patients at high risk for thromboembolism. To compare thromboembolism rates between patients with ulcerative colitis undergoing a colorectal operation and other patients undergoing colorectal operations.

METHODS: Data from the National Hospital Discharge Survey was used to compare thromboembolism rates between (1) hospitalized patients with a discharge diagnosis of ulcerative colitis and those with diverticulitis or acute respiratory failure, and (2) hospitalized patients with a discharge diagnosis of ulcerative colitis who underwent colectomy and those with diverticulitis or colorectal cancer who underwent colorectal operations.

RESULTS: Patients diagnosed with ulcerative colitis had similar or higher rates of combined venous thromboembolism (2.03%) than their counterparts with diverticulitis (0.76%) or respiratory failure (1.99%), despite the overall greater prevalence of thromboembolic risk factors in the latter groups. Discharged patients with colitis that were treated surgically did not have significantly different rates of venous or arterial thromboembolism than those with surgery for diverticulitis or colorectal cancer.

CONCLUSION: Patients with ulcerative colitis who do not undergo an operation during their hospitalization have similar or higher rates of thromboembolism than other medical patients who are considered to be high risk for thromboembolism.

Efficacy of intracolonic administration of low-molecular-weight heparin CB-01-05, compared to other low-molecular-weight heparins and unfractionated heparin, in experimentally induced colitis in rat

PURPOSE

Parenteral administration of low-molecular-weight heparins (LMWHs) and unfractionated heparin (UFH) resulted effective in improving the symptoms of experimental colitis in rat. Today, there is little information about their activity by intracolonic instillation. The scope of this study was to evaluate the ability of CB-01-05 (a LMWH with a mean molecular weight of about 5,700), compared to a series of other LMWHs and to UFH, directly instilled into the distal colon of the rat, to ameliorate dinitrobenzene (DNB)-induced experimental colitis.

METHOD

Adult male Wistar rats underwent colitis induction by intracolonic instillation of DNB. Starting 24 h after colitis induction, CB-01-05 (0.005-0.9 mg), other LMWHs (0.3-0.6 mg), and UFH (0.6 mg) were instilled, by rectal route, into the distal colon once a day for three consecutive days. On the day following the last administration, the animals were sacrificed and the distal colon was isolated, weighed, macroscopically examined, and processed for histology. Additional experiments in rat splenocytes, performed in order to elucidate the anti-inflammatory mechanisms of CB-01-05, were performed.

RESULTS

Among the tested items, only CB-01-05 at doses ranging from 0.2 to 0.9 mg was significantly effective in reducing colon weight increase and in improving both the mucosal damaged area and the histological score. The other LMWHs resulted far less effective, showing decreasing activity closely related with the decrease of their molecular weight, thus demonstrating their biological nonequivalence. CB-01-05 resulted also more active than UFH. CB-01-05 was shown to interfere with cytokines production by rat splenocytes, mainly inhibiting interferon (IFN)-gamma expression.

CONCLUSIONS

CB-01-05 instilled into the colon is well tolerated, has strong anti-inflammatory effect on DNB-induced colitis in rat, and is the most effective agent among other LMWHs and UFH. These results suggest that the anti-inflammatory activity of CB-01-05, together with its topical administration, could represent a new approach in the management of ulcerative colitis.

Oral, colonic-release low-molecular-weight heparin: an initial open study of Parnaparin-MMX for the treatment of mild-to-moderate left-sided ulcerative colitis

BACKGROUND

Efficacy of heparin and low-molecular-weight heparins (LMWHs) in inflammatory bowel disease (IBD) treatment has been suggested. The multimatrix oral formulation MMX releases active drugs in the colon, avoiding systemic absorption. Parnaparin sodium is the LMWH chosen to be carried in the MMX formulation.

AIM

To assess the safety of three different oral dosages (70, 140 and 210 mg once daily) of Parnaparin-MMX (CB-01-05) in left-sided ulcerative colitis (UC).

METHODS

Left-sided UC patients, with a mild-to-moderate relapse were enrolled. All patients received Parnaparin-MMX for 8 weeks. Clinical Activity Index (CAI), Disease Activity Index (DAI), Endoscopic Activity Index and IBD-QoL were assessed throughout the study. A strict clinical and laboratory follow-up, including assessment of anti-factor Xa activity, was performed. Clinical remission was defined as CAI <4.

RESULTS

Ten UC patients were enrolled. One patient retired for clinical deterioration. No relevant side effects, including either interference with haemostasis parameters or increased bleeding, were observed. At the end of the treatment, seven patients (70%) were in clinical remission, only one achieving endoscopic healing. Mean final CAI, DAI and IBD-QoL scores were significantly improved from baseline.

CONCLUSIONS

Parnaparin-MMX appears to be a safe treatment option in mild-to-moderate UC. Controlled studies are warranted.

Rising prevalence of venous thromboembolism and its impact on mortality among hospitalized inflammatory bowel disease patients

BACKGROUND

We sought to determine nationwide, population-based trends in rates of venous thromboembolism (VTE) among hospitalized inflammatory bowel disease (IBD) patients in the United States and to determine its mortality and economic impact.

METHODS

We analyzed discharges from the Nationwide Inpatient Sample and used ICD-9-CM codes to identify Crohn's disease (CD) and ulcerative colitis (UC) between 1998 and 2004. Rates of VTE were compared between those with and without IBD. The impact of VTE on in-hospital mortality and resource utilization was quantified using regression analysis.

RESULTS

After multivariate adjustment, both UC (OR 1.85, 95% CI 1.70-2.01) and CD discharges (OR 1.48, 95% CI 1.35-1.62) had higher rates of VTE compared to non-IBD discharges. Prevalence of VTE was greater among UC compared to CD discharges (OR 1.32, 95% CI 1.17-1.48). Among CD patients, active fistulizing disease was independently associated with greater VTE (OR 1.39, 95% CI 1.13-1.70). There was an annual 17% rise in odds of VTE among IBD admissions over 7 yr. VTE was associated with greater mortality among IBD patients (adjusted OR 2.50, 95% CI 1.83-3.43). This age- and comorbidity-adjusted excess mortality from VTE was 2.1-fold higher for IBD than for non-IBD patients (P < 0.0001). IBD patients with VTE had longer length of stay (11.7 vs 6.1 days, P < 0.0001) and incurred higher hospital charges ($47,515 vs $21,499; P < 0.0001).

CONCLUSIONS

VTE is increasingly prevalent among hospitalized IBD patients and has substantial mortality and economic impact. These findings drive the need for widespread prophylaxis against and early detection of VTE among IBD inpatients.

Unfractionated or low-molecular weight heparin for induction of remission in ulcerative colitis

BACKGROUND

There are a limited number of treatment options for patients with ulcerative colitis (UC). An increased risk of thrombosis in UC coupled with an observation that UC patients being treated with anticoagulant therapy for thrombotic events had an improvement in their bowel symptoms led to trials examining the use of unfractionated heparin (UFH) and low molecular weight heparins (LMWH) in patients with active UC.

OBJECTIVES

To review randomized trials examining the efficacy of unfractionated heparin (UFH) or low molecular weight heparins (LMWH) for remission induction in patients with ulcerative colitis.

SEARCH STRATEGY

The MEDLINE (PUBMED), and EMBASE databases, The Cochrane Central Register of Controlled Trials, the Cochrane IBD/FBD group specialized trials register, review papers on ulcerative colitis, and references from identified papers were searched in an effort to identify all randomized trials studying UFH or LMWH use in patients with ulcerative colitis. Abstracts from major gastroenterological meetings were searched to identify research published in abstract form only.

SELECTION CRITERIA

Each author independently reviewed potentially relevant trials to determine their eligibility for inclusion based on the criteria identified above. The Jadad scale was used to assess study quality. Studies published in abstract form only were included if the authors could be contacted for further information.

DATA COLLECTION AND ANALYSIS

A data extraction form was developed and used to extract data from included studies. At least 2 authors independently extracted data. Any disagreements were resolved by consensus. Data were analyzed using Review Manager (RevMan 4.2.9). Data were analyzed on an intention-to-treat basis, and treated dichotomously. In cross-over studies, only data from the first arm were included. The primary endpoint was induction of remission, as defined by the studies. Data were combined for analysis if they assessed the same treatments (UFH or LMWH versus placebo or other therapy). If a comparison was only assessed in a single trial, P-values were derived using the chi-square test. If the comparison was assessed in more than one trial, summary test statistics were derived using the Peto odds ratio and 95% confidence intervals (95% CI). The presence of heterogeneity among studies was assessed using the chi-square test (a P value of 0.10 was regarded as statistically significant). If statistically significant heterogeneity was identified the odds ratio and 95% CI were calculated using a random effects model.

MAIN RESULTS

There were 2 randomized, double-blind studies assessing LMWH versus placebo for the treatment of mild-moderate active UC. Various outcomes were assessed in the 2 studies. LMWH showed no benefit over placebo in any outcome, including clinical remission (OR 1.09; 95% CI 0.26 to 4.63; P = 0.91), clinical improvement (OR 0.73; 95% CI 0.32 to 1.66; P = 0.45 and OR 1.09; 95% CI 0.18 to 6.58; P = 0.92 in the two studies, respectively), endoscopic improvement (OR 1.35; 95% CI 0.29 to 6.18; P = 0.70), or histological improvement (OR 2.00; 95% CI 0.45 to 8.96; P = 0.37). LMWH was also not beneficial when added to standard therapy in a randomized open-label trial in which the outcome measures included clinical remission (OR 0.71; 95% CI 0.17 to 2.95; P = 0.64), clinical improvement (OR 2.00; 95% CI 0.31 to 12.75; P = 0.46), endoscopic remission (OR 0.71; 95% CI 0.17 to 2.95; P = 0.64), or endoscopic improvement (OR 1.40; 95% CI 0.34 to 5.79; P = 0.64). LMWH was well-tolerated and provided no significant benefit for quality of life. One study examining UFH versus corticosteroids in the treatment of severe UC demonstrated inferiority of UFH in clinical improvement as an outcome measure (OR 0.02; 95% CI 0 to 0.40; P = 0.01). Patients assigned to UFH did not improve clinically. More patients assigned to UFH had rectal hemorrhage as an adverse event.

AUTHORS' CONCLUSIONS

There is no evidence to support the use of UFH or LMWH for the treatment of active UC. No further trials examining these drugs for patients with UC are warranted, except perhaps a trial of UFH in patients with mild disease. Any benefit found would need to be weighed against a possible increased risk of rectal bleeding in patients with active UC.

Meta-analysis of the placebo response in ulcerative colitis

PURPOSE

The placebo response rate in randomized controlled trials (RCTs) in ulcerative colitis (UC) varies from 0 to 76%. The aims of this study were to quantify the pooled placebo response rate and identify the factors affecting it.

METHODS

We performed a meta-analysis of 110 RCTs carried out between 1955 and 2005 and published in English. Regression analysis was used to identify factors significantly modifying placebo response.

RESULTS

The pooled placebo remission rate was 23% (95%CI: 18.4-28%) and the pooled placebo improvement rate was 32.1% (95%CI: 28.1-36.3%). Multivariate analysis showed that the country where the study was performed (P = 0.025 for placebo remission and P = 0.0083 for placebo response rates) significantly influenced the placebo remission and response rates.

CONCLUSION

Placebo remission and response rates in RCTs of UC are highly variable and are significantly influenced by the country in which the RCT is performed.

P-selectin: a common therapeutic target for cardiovascular disorders, inflammation and tumour metastasis

P-selectin belongs to the family of selectin adhesion molecules, and is expressed by platelets and endothelial cells on stimulation. This pattern of expression may indicate an involvement of this molecule in inflammation and coagulation. Data from mice lacking P-selectin expression confirmed this assumption. In addition, a key role of P-selectin in the formation of tumour metastases has been established. Apparently unrelated, clinical experience has pointed towards a detrimental interaction of inflammation and cancer with thromboembolic diseases and vice versa. Therefore, targeting molecules such as P-selectin contributing to coagulation, inflammation and metastasis may offer novel therapeutic strategies to treat chronic inflammatory diseases and metastatic cancer. The authors aim to critically evaluate the contribution of P-selectin in these diseases, and discuss the value of therapeutic inhibition of P-selectin functions in coagulation, inflammation and metastasis.

Meta-analysis: The utility and safety of heparin in the treatment of active ulcerative colitis

BACKGROUND

The use of heparin for the treatment of ulcerative colitis has been evaluated in several open and controlled trials, with varying outcomes.

AIM

To evaluate the efficacy and safety of heparin as supplemental therapy compared with conventional therapy in patients with ulcerative colitis.

METHODS

All randomized trials comparing heparin supplementation to conventional therapy were included from electronic databases. Statistical analysis was performed with review manager 4.2.8 (The Cochrane Collaboration, Oxford, UK). Sub-analysis and sensitivity analysis were also performed.

RESULTS

Eight randomized-controlled trials, investigating a total of 454 participants, met the inclusion criteria. The odds ratio (OR) for the efficacy of heparin supplementation vs. conventional therapy was 0.78 (95% CI = 0.50-1.21). Few serious adverse events were observed. The OR for the efficacy of unfractionated heparin and low-molecular-weight heparin vs. conventional therapy was 0.26 (95% CI = 0.07-0.93) and 0.92 (95% CI = 0.57-1.47), respectively. The OR for the efficacy of heparin vs. conventional therapy with placebo was 0.87 (95% CI = 0.53-1.44).

CONCLUSIONS

Our meta-analysis suggests that administration of heparin in patients with ulcerative colitis is safe, but no additive benefit over conventional therapy is indicated.

The microvascular thrombi of colonic tissue in ulcerative colitis

Mucosal microvascular thrombi in rectal biopsies were observed in some ulcerative colitis (UC). Heparin may be effective in steroid resistant UC in some studies, however, the new results of meta-analysis demonstrated a non-significant effect of heparin in controlled clinical trials, differing markedly from observational studies. The objective of this study was to identify colonic microvascular thrombi in larger cases with UC, and analyse its possible risk factors: age, gender, histologic score, extent of lesions and operation or biopsy specimens, and assess the significance of microvascular thrombosis in patients with UC. The microvascular thrombi were identified by immunohistochemical staining with anti-CD61 monoclonal antibody and Martius scarlet blue (MSB) staining in 40 colonic tissue samples of UC (31 biopsy specimens and nine operated cases) and 12 cases of normal colon tissue from operated colonic carcinoma. Logistic regression analysis was used to assess the relationship of age, gender, degree of histology, origin of the specimens, extent of lesions and microvascular thrombi examined. Microvascular thrombi were positive in 14 of 40 UC cases, and none in the controls. The presence of microvascular thrombi was related to operation specimens with odds ratio 11.667, P=0.0179, it might be also related to histologic score (OR=1.350) and extent of lesions (OR=1.619). These results suggest that microvascular thrombosis may be one of the important pathogenesis in some UC, and that the effect of anticoagulant treatment still needs to be assessed.

The anti-inflammatory effects of heparin and related compounds

Heparin is a glycosaminoglycan well known for its anticoagulant properties. In addition, heparin possesses anti-inflammatory effects. Although the mechanisms responsible for the anticoagulant effects of heparin are well understood, those underlying its anti-inflammatory effects are not. This review presents some of the evidence from clinical and animal studies supporting an anti-inflammatory role for heparin and heparin-related derivatives. Potential mechanisms by which heparin can exert its anti-inflammatory effects are discussed. The clinical use of heparin as an anti-inflammatory agent has been held back by the fear of bleeding. Development of nonanticoagulant heparins or heparin derivatives should mitigate this concern.

Randomized, placebo-controlled trial of low molecular weight heparin in active ulcerative colitis

BACKGROUND

In several open and 1 controlled trial, unfractionated heparin was effective in the treatment of active ulcerative colitis (UC). Low molecular weight heparin (LMWH) had a similar effect in several open studies.

METHODS

We studied the efficacy, safety, and tolerability of LMWH in mild to moderately active UC in a randomized, double-blind, placebo-controlled trial. In all, 29 patients with a mild or moderate recurrence of UC during salicylate treatment were randomized to receive either reviparin 3,436 IU (n = 15) subcutaneously twice daily or placebo (n = 14). The study period was 8 weeks. Treatment was discontinued if there was no improvement at 4 weeks or at any disease progression. Primary outcome measure was clinical improvement at 8 weeks measured by the Colitis Activity Index (CAI) and the Clinical Symptoms Grading (CSG, based on the CAI). Endoscopic and histologic grading and quality of life as measured by the Inflammatory Bowel Disease Questionnaire (IBDQ) were secondary outcome measures. Patients were closely monitored for adverse events.

RESULTS

Twenty of 29 patients finished the 8-week treatment period (reviparin versus placebo: 11 versus 9; P = 0.70). There was no difference in CSG, CAI, endoscopic and histologic grading, or IBDQ. Treatment was well tolerated and no serious adverse events occurred.

CONCLUSION

In this study, treatment with LMWH showed no significant clinical advantage compared to placebo in mild to moderately active UC.

A meta-analysis of the placebo rates of remission and response in clinical trials of active ulcerative colitis

BACKGROUND & AIMS

Knowledge of the placebo outcomes and understanding specific study features that influence these outcomes is important for designing future clinical trials evaluating therapy of ulcerative colitis (UC). The aims of this study were to estimate the placebo rates of remission and response in placebo-controlled, randomized clinical trials for active UC and to identify factors influencing these rates.

METHODS

We performed a systematic review and meta-analysis of placebo-controlled, randomized clinical trials evaluating therapies for active UC identified from MEDLINE from 1966 through 2005.

RESULTS

Forty studies met the inclusion criteria. The pooled estimates of the placebo rates of remission and response were 13% (95% confidence interval, 9%-18%; range, 0%-40%; median, 12%) and 28% (95% confidence interval, 23%-33%; range, 0%-67%; median, 30%), respectively, both with significant heterogeneity. Studies that used more stringent definitions of outcomes had lower placebo rates of remission and response. Study duration, number of study visits, disease duration, baseline composite and rectal bleeding scores of the disease activity index, and inclusion of endoscopic mucosal healing as the remission definition all were associated with the placebo remission rate.

CONCLUSIONS

Rates of remission in the placebo arm of UC clinical trials ranges from 0% to 40%. The placebo remission rates are influenced by the trial length, number of study visits, use of stricter remission definitions, and design features that enroll patients with more active disease. These factors should be considered when designing future placebo-controlled clinical trials in patients with active UC.

Medical management of left-sided ulcerative colitis and ulcerative proctitis: critical evaluation of therapeutic trials

BACKGROUND

The goal of this work was to critically evaluate the published studies on the treatment of ulcerative proctitis (UP) and left-sided ulcerative colitis (L-UC). The results of this review provided the content for the accompanying treatment guidelines, Clinical Guidelines for the Medical Management of Left-sided Ulcerative Colitis and Ulcerative Proctitis: Summary Statement.

METHODS

All English language articles published between 1995 and September 2005 were identified through a comprehensive literature search using OVID and PubMed. The quality of the data supporting or rejecting the use of specific therapies was categorized by a data quality grading scale. An "A+" grade was assigned to treatment supported by multiple high-quality randomized controlled trials with consistent results, whereas a "D" grade was given to therapy supported only by expert opinion. The therapeutic efficacy of a treatment was defined by its success in treating UP and L-UC compared with placebo. A medication was ranked as "excellent" if it was specifically studied for UP and L-UC and had consistently positive results compared with placebo or another agent. Quality and efficacy scores were agreed on by author consensus.

RESULTS

For the acute treatment of UP or L-UC, the rectally administered corticosteroids and mesalazine (5-ASA), either alone or in combination with oral 5-ASAs, are the most effective therapy: evidence quality, A+; efficacy, excellent. Only rectally administered 5-ASA received an A+/excellent rating for maintenance of remission. Infliximab received an A+ grade for induction and maintenance of remission but only a "good" rating because the studies were performed in all UC, not specifically UP or L-UC.

CONCLUSIONS

This critical evaluation of treatment provides a "report card" on medications available for the management of patients with UP and L-UC. The guidelines should provide a useful reference and supplement for physicians treating UC patients.

Vicious circles in inflammatory bowel disease

BACKGROUND

Inflammatory bowel disease can present with a bewildering array of disease manifestations whose overall impact on patient health is difficult to disentangle. The multitude of disease complications and therapeutic side effects result in conflicting ideas on how to best manage a patient. The aim of the study is to test the usefulness of influence diagrams in resolving conflicts centered on managing complex disease processes.

METHODS

The influences of a disease process and the ensuing medical interventions on the health of a patient with inflammatory bowel disease are modeled by an influence diagram. Patient health is the focal point of multiple influences affecting its overall strength. Any downstream influence represents the focal point of other preceding upstream influences. The mathematics underlying the influence diagram is similar to that of a decision tree. Its formalism allows one to consider additive and inhibitory influences and include in the same analysis qualitatively different types of parameters, such as diagnoses, complications, side effects, and therapeutic outcomes.

RESULTS

Three exemplary cases are presented to illustrate the potential use of influence diagrams. In all three case scenarios, Crohn's disease resulted in disease manifestations that seemingly interfered with its own therapy. The presence of negative feedback loops rendered the management of each case particularly challenging. The analyses by influence diagrams revealed subtle interactions among the multiple influences and their joint contributions to the patient's overall health that would have been difficult to appreciate by verbal reasoning alone.

CONCLUSION

Influence diagrams represent a decision tool that is particularly suited to improve decision-making in inflammatory bowel disease. They highlight key factors of a complex disease process and help to assess their quantitative interactions.

Low-molecular-weight heparin (enoxaparin) as adjuvant therapy in the treatment of active ulcerative colitis: a randomized, controlled, comparative study

BACKGROUND

Heparin could be beneficial to the treatment of active ulcerative colitis because of its anticoagulant, anti-inflammatory and immunomodulatory properties.

AIM

To evaluate the tolerability, safety and efficacy of low-molecular-weight heparin as adjuvant therapy in patients with active ulcerative colitis.

METHODS

Thirty-four adult patients with active ulcerative colitis were consecutively included in a prospective, randomized, comparative study, and were treated for 12 weeks. Eighteen patients in the 'standard therapy' group were treated with aminosalicylates and weekly tapered corticosteroids. Sixteen patients in the 'heparin therapy' group were treated with standard therapy plus enoxaparin 100 Anti-Xa IU/kg/day subcutaneously.

RESULTS

Seventeen patients in the 'standard therapy' group and 15 patients in the 'heparin therapy' group completed the study. Tolerability and compliance to therapy were excellent and no withdrawals were noted because of complications. There was a significant improvement in the disease severity in both groups (P<0.001), without any difference between them (P=not significant). Both treatment groups showed similar proportions of disease improvement (65% and 73%, respectively; P=not significant). There were no significant differences in inflammation (fibrinogen, ESR, CRP) and coagulation (thrombin-antithrombin complex, F1+2, D-dimers) parameters during and at the end of the study between treatment groups.

CONCLUSION

Adjuvant administration of low-molecular heparin in patients with active ulcerative colitis is safe and well tolerated, but no additive benefit over standard therapy for ulcerative colitis was noted.

Thrombosis and inflammatory bowel disease

Interaction between thrombosis and inflammation is increasingly recognized. With this, interest has arisen in the role of thrombosis in inflammatory conditions, including the inflammatory bowel diseases. Although the association between active inflammatory bowel disease and thromboembolic complications has long been known, there has been a resurgence in research into the role of thrombosis and the hemostatic system in the pathogenesis of both ulcerative colitis and Crohn's disease. Here we review the increased frequency of thromboembolic complications occurring in patients with inflammatory bowel disease; whether thrombosis might play a part in the initiation and maintenance of inflammation in inflammatory bowel disease; abnormalities of the coagulation system found in patients with inflammatory bowel disease; platelet dysfunction in inflammatory bowel disease; the mechanisms by which hemostatic processes might be proinflammatory in inflammatory bowel disease; and how these interactions might impact not only on the prevention of complications, but also on the treatment of the underlying inflammation in inflammatory bowel disease.

Medical therapy for ulcerative colitis: the state of the art and beyond

Ulcerative colitis (UC) is an idiopathic inflammatory condition of the large intestine. Recent advances in our understanding of the pathogenesis of UC have led to the development of novel treatments for this often debilitating condition. Aside from aminosalicylates and corticosteroids, drugs that have been used for decades in the treatment of UC, biologic agents, in addition to medications targeting specific effector mechanisms involved in the inflammatory cascade, have been used in patients with UC with varying degrees of success. Clinicians have never had as many therapeutic options for UC as they do today. Herein we review the variety of treatment options, both standard and investigational, that are available for patients with UC.