Intra-abdominal venous and arterial thromboembolism in inflammatory bowel disease

Contribution of Blood Vessel Activation, Remodeling and Barrier Function to Inflammatory Bowel Diseases

Inflammatory bowel diseases (IBDs) consist of a group of chronic inflammatory disorders with a complex etiology, which represent a clinical challenge due to their often therapy-refractory nature. In IBD, inflammation of the intestinal mucosa is characterized by strong and sustained leukocyte infiltration, resulting in the loss of epithelial barrier function and subsequent tissue destruction. This is accompanied by the activation and the massive remodeling of mucosal micro-vessels. The role of the gut vasculature in the induction and perpetuation of mucosal inflammation is receiving increasing recognition. While the vascular barrier is considered to offer protection against bacterial translocation and sepsis after the breakdown of the epithelial barrier, endothelium activation and angiogenesis are thought to promote inflammation. The present review examines the respective pathological contributions of the different phenotypical changes observed in the microvascular endothelium during IBD, and provides an overview of potential vessel-specific targeted therapy options for the treatment of IBD.

Presentation and Management of Arterial Thromboembolisms during Active Inflammatory Bowel Disease: Case Series and Literature Review

BACKGROUND

Active inflammatory bowel disease (IBD) is associated with considerable risk for thromboembolism; however, arterial thromboembolism is rare and associated with considerable morbidity and mortality. Their management requires careful coordination between multiple providers, and as a consequence, much of the published literature is limited to case reports published across specialties.

METHODS

We examined our recent institutional experience with aortoiliac, mesenteric, and peripheral arterial thromboembolisms in patients with either Crohn's disease or ulcerative colitis. To supplement our experience, a comprehensive literature review was performed using MEDLINE and EMBASE databases from 1966 to 2019. Patient demographics, flare/thromboembolism management, and outcomes were abstracted from the selected articles and our case series.

RESULTS

Fifty-two patients with IBD, who developed an arterial thromboembolism, were identified (49 from published literature and 3 from our institution). More than 82% of patients presented during an active IBD flare. Surgical intervention was attempted in 77% of patients, which included open thromboembolectomy, catheter-directed thrombolysis, or bowel resection. Thromboembolism resolution was achieved in 76% of patients with comparable outcomes with either catheter-directed thrombolysis or open thrombectomy (83.3% vs. 68.2%). Nearly one-third of patients underwent small bowel resection or colectomy. In 2 patients, thromboembolism resolution was achieved only after total abdominal colectomy for severe pancolitis. Multiple thromboembolectomies were associated with higher risk for amputation. Overall mortality was 11.5% but was greatest for occlusive aortoiliac and mesenteric thromboembolism (14.3% and 57%, respectively). All survivors of occlusive superior mesenteric artery thromboembolism suffered short gut syndrome requiring small bowel transplant.

CONCLUSIONS

Patients with IBD, who develop an arterial thromboembolism, can expect overall poor outcomes. Catheter-directed thrombolysis achieved comparable outcomes with open thromboembolectomy without undue bleeding risk. Total abdominal colectomy for moderate-to-severe pancolitis is an emerging strategy in the management of refractory arterial thromboembolism. Successful surgical management may include open thromboembolectomy, catheter-directed thrombolysis, and bowel resection when indicated.

Thrombosis in inflammatory bowel diseases: what's the link?

Inflammatory bowel disease affects more than 2 million people in Europe, with almost 20% of patients being diagnosed in pediatric age. Patients with inflammatory bowel disease are at increased risk of thromboembolic complications which may affect patients’ morbidity and mortality. The risk of the most common thromboembolic events, such as deep venous thrombosis and pulmonary embolism, are estimated to be three-fold increased compared to controls, but many other districts can be affected. Moreover, patients with ulcerative colitis and Crohn’s disease experience thromboembolic events at a younger age compared to general population. Many factors have been investigated as determinants of the pro-thrombotic tendency such as acquired risk factors or genetic and immune abnormalities, but a unique cause has not been found. Many efforts have been focused on the study of abnormalities in the coagulation cascade, its natural inhibitors and the fibrinolytic system components and both quantitative and qualitative alterations have been demonstrated. Recently the role of platelets and microvascular endothelium has been reviewed, as the possible link between the inflammatory and hemostatic process.

Colectomy is a risk factor for venous thromboembolism in ulcerative colitis

AIM: To compare venous thromboembolism (VTE) in hospitalized ulcerative colitis (UC) patients who respond to medical management to patients requiring colectomy.

METHODS: Population-based surveillance from 1997 to 2009 was used to identify all adults admitted to hospital for a flare of UC and those patients who underwent colectomy. All medical charts were reviewed to confirm the diagnosis and extract clinically relevant information. UC patients were stratified by: (1) responsive to inpatient medical therapy (n = 382); (2) medically refractory requiring emergent colectomy (n = 309); and (3) elective colectomy (n = 329). The primary outcome was the development of VTE during hospitalization or within 6 mo of discharge. Heparin prophylaxis to prevent VTE was assessed. Logistic regression analysis determined the effect of disease course (i.e., responsive to medical therapy, medically refractory, and elective colectomy) on VTE after adjusting for confounders including age, sex, smoking, disease activity, comorbidities, extent of disease, and IBD medications (i.e., corticosteroids, mesalamine, azathioprine, and infliximab). Point estimates were presented as odds ratios (OR) with 95%CI.

RESULTS: The prevalence of VTE among patients with UC who responded to medical therapy was 1.3% and only 16% of these patients received heparin prophylaxis. In contrast, VTE was higher among patients who underwent an emergent (8.7%) and elective (4.9%) colectomy, despite greater than 90% of patients receiving postoperative heparin prophylaxis. The most common site of VTE was intra-abdominal (45.8%) followed by lower extremity (19.6%). VTE was diagnosed after discharge from hospital in 16.7% of cases. Elective (adjusted OR = 3.69; 95%CI: 1.30-10.44) and emergent colectomy (adjusted OR = 5.28; 95%CI: 1.93-14.45) were significant risk factors for VTE as compared to medically responsive UC patients. Furthermore, the odds of a VTE significantly increased across time (adjusted OR = 1.10; 95%CI: 1.01-1.20). Age, sex, comorbidities, disease extent, disease activity, smoking, corticosteroids, mesalamine, azathioprine, and infliximab were not independently associated with the development of VTE.

CONCLUSION: VTE was associated with colectomy, particularly, among UC patients who failed medical management. VTE prophylaxis may not be sufficient to prevent VTE in patients undergoing colectomy.

Aortitis and aortic occlusion in Crohn disease

Patients with Crohn disease (CD) or ulcerative colitis are known to be at increased risk of arterial thromboembolic complications. We report the case of a 33-year-old woman suffering from CD for 19 years who presented lower limb claudication. Computed tomography scan revealed an aortoiliac occlusion extending from the level of the inferior mesenteric artery to both iliac bifurcations. Endovascular recanalization was attempted as a first option but failed. We then performed an aortobi-femoral bypass through a left retroperitoneal approach that allowed a total relief of the symptoms. Histologic study of the aorta demonstrated a nonspecific aortitis with lymphohistiocytic cell infiltration in the media and adventitia tunica. There was no signs of associated vasculitis. At the light of a literature review, we discussed our surgical strategy and the inflammation of the aortic wall as local factor of thrombosis that has never been previously described.

Inflammatory bowel disease and thromboembolism

Patients with inflammatory bowel disease (IBD) have an increased risk of vascular complications. Thromboembolic complications, both venous and arterial, are serious extraintestinal manifestations complicating the course of IBD and can lead to significant morbidity and mortality. Patients with IBD are more prone to thromboembolic complications and IBD per se is a risk factor for thromboembolic disease. Data suggest that thrombosis is a specific feature of IBD that can be involved in both the occurrence of thromboembolic events and the pathogenesis of the disease. The exact etiology for this special association between IBD and thromboembolism is as yet unknown, but it is thought that multiple acquired and inherited factors are interacting and producing the increased tendency for thrombosis in the local intestinal microvasculature, as well as in the systemic circulation. Clinicians' awareness of the risks, and their ability to promptly diagnose and manage tromboembolic complications are of vital importance. In this review we discuss how thromboembolic disease is related to IBD, specifically focusing on: (1) the epidemiology and clinical features of thromboembolic complications in IBD; (2) the pathophysiology of thrombosis in IBD; and (3) strategies for the prevention and management of thromboembolic complications in IBD patients.

Risk of cerebrovascular accidents and ischemic heart disease in patients with inflammatory bowel disease: a systematic review and meta-analysis

BACKGROUND & AIMS

Inflammatory bowel disease (IBD) is associated with an increased risk of venous thromboembolic disease. However, it is unclear whether IBD modifies the risk of arterial thromboembolic events, including cerebrovascular accidents (CVA) and ischemic heart disease (IHD).

METHODS

We performed a systematic review and meta-analysis of cohort and case-control studies that reported incident cases of CVA and/or IHD in patients with IBD and a non-IBD control population (or compared with a standardized population). We calculated pooled odds ratios (ORs) with 95% confidence intervals (CIs).

RESULTS

We analyzed data from 9 studies (2424 CVA events in 5 studies, 6478 IHD events in 6 studies). IBD was associated with a modest increase in the risk of CVA (5 studies; OR, 1.18; 95% CI, 1.09-1.27), especially among women (4 studies; OR, 1.28; 95% CI, 1.17-1.41) compared with men (OR, 1.11; 95% CI, 0.98-1.25), and in young patients (<40-50 y old). The increase in risk was observed for patients with Crohn's disease and in those with ulcerative colitis. IBD also was associated with a 19% increase in the risk of IHD (6 studies; OR, 1.19; 95% CI, 1.08-1.31), both in patients with Crohn's disease and ulcerative colitis. This risk increase was seen primarily in women (4 studies; OR, 1.26; 95% CI, 1.18-1.35) compared with men (OR, 1.05; 95% CI, 0.92-1.21), in young and old patients. IBD was not associated with an increased risk of peripheral arterial thromboembolic events. Considerable heterogeneity was observed in the overall analysis.

CONCLUSIONS

IBD is associated with a modest increase in the risk of cardiovascular morbidity (from CVA and IHD)-particularly in women. These patients should be counseled routinely on aggressive risk factor modification.

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.

Reduced plasma fibrin clot permeability and susceptibility to lysis in patients with inflammatory bowel disease: a novel prothrombotic mechanism

BACKGROUND

Inflammatory bowel disease (IBD) is associated with an increased risk of thromboembolism. Its mechanism is still unclear. Altered fibrin clot properties have been reported in patients with thromboembolism and those with chronic inflammatory states. We investigated whether fibrin characteristics are abnormal in IBD.

METHODS

Ex vivo plasma fibrin clot permeability (Ks), compaction, turbidity, and efficiency of fibrinolysis were assessed in 85 consecutive patients with IBD, including 47 with ulcerative colitis (UC) and 38 with Crohn's disease (CD), all with no history of thromboembolism. Forty-eight patients matched for age and sex served as controls.

RESULTS

Compared with controls, patients with UC and CD had 29.5% and 35.7% lower Ks associated with 13.8% and 23.1% lower compaction, respectively (all P < 0.001). Patients with UC and CD had higher maximum clot absorbance (+8.9%, P = 0.008, and +15.2%, P < 0.0001, respectively), higher maximum D-dimer released from clots (D-D(max), +27.0%, P = 0.01, and +28.7%, P < 0.0001, respectively), and prolonged clot lysis time (+19.0%, P < 0.0001, and +25.5%, P < 0.0001, respectively). Lag phase was similar in both group of patients. D-D(max) was the only parameter that differed between patients in the UC and CD groups, being higher in CD (P = 0.04). The multiple linear regression model showed that in patients with UC, but not with CD, Ks, compaction, lysis time, and D-D(max) were all independently associated with disease activity. In patients with CD, Ks and lysis time were independently predicted by fibrinogen and C-reactive protein.

CONCLUSIONS

Both UC and CD are characterized by formation of dense fibrin networks relatively resistant to lysis. Prothrombotic clot phenotype might represent a novel mechanism increasing thrombotic risk in IBD.

Septic pylephlebitis as a rare complication of Crohn's disease

Thrombophlebitis of the portal venous system (PVS) with superimposed bacterial infection (septic pylephlebitis) is an extremely rare complication of Crohn's disease (CD), and therefore diagnosis of septic pylephlebitis is difficult without high clinical suspicion. A 16-year old male patient who was diagnosed with CD 3 months earlier was admitted with recurrent fever and abdominal pain. CD activity had been well controlled with conventional medical treatment during a follow-up period. Abdominal contrast-enhanced computed tomography showed massive thrombosis in the PVS without evidence of intra-abdominal infection, and blood cultures were positive for Streptococcus viridians. There was no evidence of deep vein thrombosis or pulmonary thromboembolism, and all laboratory tests for thrombophilia were normal. Based on these findings, the patient was diagnosed with septic pylephlebitis complicated with CD, and was successfully treated with intravenous antibiotic therapy combined with anticoagulation. This case suggests that early comprehensive evaluation is crucial for immediate diagnosis and proper treatment of septic pylephlebitis in patients with CD who present with fever and abdominal pain of unknown origin, even with stable disease activity and absence of other intra-abdominal infections.

Clinical and radiographic presentation of superior mesenteric vein thrombosis in Crohn's disease: a single center experience

BACKGROUND

Mesenteric vein thrombosis (MVT) is a rare and frequently underdiagnosed complication of Crohn's disease (CD). This study describes the clinical and radiological characteristics of CD /patients with superior mesenteric vein thrombosis (MVT) diagnosed by CT/MRI.

PATIENTS AND METHODS

The database of Crohn's disease patients treated in Sheba Medical Center between 2005-2010 was searched for MVT diagnosis. Imaging studies of identified patients were retrieved and reviewed by an experienced abdominal radiologist. MVT was defined by superior mesenteric vein obliteration and/or thrombus in the vessel lumen on abdominal imaging. The clinical and radiologic data of these patients were collected from the medical records.

RESULTS

MVT was demonstrated in 6/460 CD patients. Five patients had stricturing disease, and one patient had a combined fistulizing and stricturing disease phenotype. All patients had small bowel disease, but 3/6 also had colonic involvement. No patient had a prior thromboembolic history or demonstrable hypercoagulability. One patient had an acute SMV thrombus demonstrable on CT scanning, the remaining patients showed an obliteration of superior mesenteric vein. Two patients received anticoagulation upon diagnosis of thrombosis. No subsequent thromboembolic events were recorded.

CONCLUSIONS

The incidence of mesenteric vein thrombosis is likely to be underestimated in patients with Crohn's disease. Both CT and MRI imaging demonstrate the extent of enteric disease and coincident SMV thrombosis. In our cohort, thrombosis was associated with stricturing disease of the small bowel. The clinical impact of SMV thrombosis and whether anticoagulation is mandatory for all of these patients remains to be determined.

Comorbidity in inflammatory bowel disease

Patients with inflammatory bowel disease (IBD) can be affected by other unrelated diseases. These are called comorbid conditions, and can include any secondary health problem that affects a person suffering from a primary or main disease, and which is neither linked physiopathologically to the primary condition, nor is it due to the treatments used for the primary condition or to its long-term anatomical or physiological consequences. Different comorbid conditions, as well as their influence on IBD, are discussed.

Mesenteric venous thrombosis

First differentiated from arterial causes of acute mesenteric ischemia 75 years ago, acute mesenteric venous thrombosis (MVT) is an uncommon disorder with non-specific signs and symptoms, the diagnosis of which requires a high index of suspicion. The location, extent, and rapidity of thrombus formation determine whether intestinal infarction ensues. Etiologies, when identified, usually can be separated into local intra-abdominal factors and inherited or acquired hypercoagulable states. The diagnosis is most often made by contrast-enhanced computed tomography, though angiography and exploratory surgery still have important diagnostic as well as therapeutic roles. Anticoagulation prevents clot propagation and is associated with decreased recurrence and mortality. Thrombectomy and thrombolysis may preserve questionably viable bowel and should be considered under certain circumstances. Evidence of infarction mandates surgery and resection whenever feasible. Although its mortality rate has fallen over time, acute MVT remains a life-threatening condition requiring rapid diagnosis and aggressive management. Chronic MVT may manifest with complications of portal hypertension or may be diagnosed incidentally by noninvasive imaging. Management of chronic MVT is directed against variceal hemorrhage and includes anticoagulation when appropriate; mortality is largely dependent on the underlying risk factor.

Thromboembolism in inflammatory bowel diseases: a report from Saudi Arabia

Thromboembolism (TE) is a serious but under-recognized complication of inflammatory bowel disease (IBD). This is specially so in developing countries where the incidence of IBD is low. In Saudi Arabia, IBD is considered to be rare, but the incidence is increasing. Where the clinical manifestations resemble those of developed countries, TE as a complication of IBD is considered to be very rare. This report describes six IBD patients with TE. This importance of the complication of TE is stressed, and physicians caring for these patients should be aware of it in order to obviate potential morbidity and mortality.

[A case of inferior vena cava thrombosis and acute pancreatitis in a patient with ulcerative colitis]

A 21-year-old man admitted complaining of sudden severe epigastric pain for 1 day. He had been diagnosed as ulcerative colitis (UC) and taking mesalazine for two months. UC was in nearly complete remission at admission. He never drank an alcohol, and serum amylase was 377 IU/L. CT scan showed inferior vena cava (IVC) thrombosis in addition to mild acute pancreatitis. To evaluate the cause of acute pancreatitis and IVC thrombosis, magnetic resonance cholangiopancreatogram (MRCP), endoscopic ultrasonogram (EUS), lower extremity Doppler ultrasonogram (US) and blood test of hypercoagulability including factor V, cardiolipin Ab, protein C, protein S1, antithrombin III, and anti phospholipids antibody were performed. There was no abnormality except mild acute pancreatitis and IVC thrombosis in all the tests. He was recommended to stop taking mesalazine and start having anticoagulation therapy. After all symptoms disappeared and amylase returned normal, rechallenge test with mesalazine was done. Flare-up of abdominal pain occurred and the elevation of serum amylase was observed. Ulcerative colitis came to complete remission with short-term steroid monotherapy. Acute pancreatitis and IVC thrombosis were completely resolved after 3-month anticoagulation therapy with no more mesalazine. We postulated that IVC thrombosis occurred due to hypercoagulable status of UC and intra-abdominal inflammation caused by mesalazine-induced pancreatitis.

How much do we need to worry about venous thromboembolism after hospital discharge? A study of colorectal surgery patients using the National Surgical Quality Improvement Program database

PURPOSE

It is well recognized that the increased risk of a postoperative venous thrombotic event extends beyond the inpatient treatment period. The purpose of this study was to determine the 30-day incidence and risk factors associated with the occurrence of early postdischarge symptomatic venous thromboembolic events in patients who have undergone major colorectal surgery.

METHODS

The National Surgical Quality Improvement Program database was queried for patients who had undergone a colon or rectal resection during the study period (2005-2008). Patient demographics, preoperative risk factors, and operative variables were recorded. The primary outcomes were occurrence of deep venous thrombosis requiring therapy or pulmonary embolism within 30 days after initial surgery. The occurrence of postdischarge venous thromboembolic events was calculated from the days to primary outcome and days from operation to discharge. Univariate and multivariate linear regression models incorporating pre- and intraoperative variables as well as the occurrence of a major or minor complication were used to evaluate the effect of these clinical factors on the early postdischarge venous thromboembolic event rate.

RESULTS

A total of 52,555 patients were included in the initial analysis. A total of 240 deep venous thromboses were diagnosed in the postdischarge setting giving a postdischarge incidence of 0.47%. One hundred thirty cases of a pulmonary embolus were diagnosed (0.26% incidence) with 30 patients having a concurrent deep venous thrombosis and pulmonary embolus. The overall cumulative postdischarge symptomatic venous thromboembolic incidence was 0.67% (n = 340). Obesity, preoperative steroid use, "bleeding disorder," ASA class III, and postoperative (major and minor) complications were all independently associated with an increased risk of an early postdischarge venous thromboembolic event.

CONCLUSION

This study has identified risk factors that may help stratify patients into different risk profiles and offer prolonged prophylaxis to patients at increased risk on the basis of preoperative risk factors and postoperative complications.

Intra-aortic mural thrombosis and splenic infarction in association with ulcerative colitis

BACKGROUND

Arterial thrombosis is a very rare, but recognised complication of inflammatory bowel disease that can result in significant morbidity and mortality.

CASE PRESENTATION

We present the case of a 48-year-old female with previously well-controlled ulcerative colitis who presented with severe left upper quadrant abdominal pain. Imaging investigations subsequently revealed a large intra-aortic mural thrombus extending into the coeliac axis complicated by splenic infarction. This occurred in the absence of other prothrombotic states such as thrombophilias or vasculitis.

CONCLUSION

This case highlights the frequently overlooked association between inflammatory bowel disease and arterial thrombosis.