Clinical presentation of venous thromboembolism in inflammatory bowel disease

BACKGROUND AND AIMS

Patients with inflammatory bowel disease (IBD) are at increased risk of venous thromboembolism (VTE), but data on frequency, site of thrombosis and risk factors are limited. We sought to determine prevalence, incidence as well as location and clinical features of first VTE among IBD patients.

METHODS

We evaluated a cohort of 2811 IBD patients for a history of symptomatic, objectively confirmed first VTE, recruited from 14 referral centers. Patients with VTE before IBD diagnosis or cancer were excluded. Incidence rates were calculated based on person-years from IBD diagnosis to first VTE or end of follow-up, respectively.

RESULTS

2784 patients (total observation time 24,778 person-years) were analyzed. Overall, of 157 IBD patients with a history of VTE, 142 (90.4%) had deep vein thrombosis (DVT) and/or pulmonary embolism (PE), whereas 15 (9.6%) had cerebral, portal, mesenteric, splenic or internal jugular vein thrombosis. The prevalence and incidence rate of all VTE was 5.6% and 6.3 per 1000 person years, respectively. Patients with VTE were older at IBD diagnosis than those without VTE (34.4±14.8years vs 32.1±14.4years, p=0.045), but did not differ regarding sex, underlying IBD and disease duration. 121 (77.1%) VTE were unprovoked, 122 (77.7%) occurred in outpatients and 78 (60.9%) in patients with active disease. Medication at first VTE included corticosteroids (42.3%), thiopurines (21.2%), and infliximab (0.7%).

CONCLUSION

VTE is frequent in IBD patients. Most of them are unprovoked and occur in outpatients. DVT and PE are most common and unusual sites of thrombosis are rare.

Inflammatory bowel disease is a risk factor for recurrent venous thromboembolism

BACKGROUND & AIMS

Patients with inflammatory bowel disease (IBD) are at increased risk of a first venous thromboembolism (VTE), yet their risk of recurrent VTE is unknown. We performed a cohort study to determine the risk for recurrent VTE among patients with IBD compared with subjects without IBD.

METHODS

We assessed 2811 patients with IBD for a history of VTE, recruited from outpatient clinics at 14 referral centers (June 2006-December 2008). Patients with VTE before a diagnosis of IBD or those not confirmed to have VTE, cancer, or a VTE other than deep vein thrombosis or pulmonary embolism, were excluded. Recurrence rates were compared with 1255 prospectively followed patients without IBD that had a first unprovoked VTE (not triggered by trauma, surgery, or pregnancy). The primary end point was symptomatic, objectively confirmed, recurrent VTE after discontinuation of anticoagulation therapy after a first VTE.

RESULTS

Overall, of 116 IBD patients who had a history of first VTE, 86 were unprovoked. The probability of recurrence 5 years after discontinuation of anticoagulation therapy was higher among patients with IBD than patients without IBD (33.4%; 95% confidence interval [CI]: 21.8-45.0 vs 21.7%; 95% CI: 18.8-24.6; P = .01). After adjustment for potential confounders, IBD was an independent risk factor of recurrence (hazard ratio = 2.5; 95% CI: 1.4-4.2; P = .001).

CONCLUSIONS

Patients with IBD are at an increased risk of recurrent VTE compared to patients without IBD.

Multicenter retrospective evaluation of capsule endoscopy in clinical routine

BACKGROUND AND STUDY AIMS

The small bowel is anatomically difficult to examine; disease conditions are rarely located in it, but can be serious. Neither conventional radiography nor push enteroscopy has sufficient sensitivity and specificity to detect distinct lesions. Wireless capsule endoscopy can theoretically allow imaging of the entire small bowel, with only minimal discomfort for the patient.

PATIENTS AND METHODS

Between November 2001 and May 2003, 191 patients received 195 capsules. Data were collected retrospectively from consecutive patients in three centers. The indications for capsule endoscopy were obscure or occult bleeding, suspected Crohn's disease, or other reasons in 151, 25, and 15 patients, respectively. The clinical outcome after 6 months was evaluated on the basis of interviews with patients or relatives.

RESULTS

Visualization of the entire small bowel was adequate in 78.4 % of the examinations. The colon was not reached in 16.9 % of cases, and there were minor technical problems in 4.6 %. Relevant pathological findings were identified in 56.2 % of 151 patients with obscure bleeding or iron-deficiency anemia (64 % of whom received blood transfusions). The most common findings were angiodysplasia in 39.7 % of cases and ulcers of the small bowel in 7.3 %. In addition, individual cases of tumors and parasitic worms were detected. Seven of the 25 patients with suspected Crohn's disease (28 %) had the disease confirmed. Three of five patients with polyposis syndrome of the colon were found to have polyps in the small bowel.

CONCLUSIONS

Wireless capsule endoscopy can be recommended as part of the routine work-up in patients with obscure bleeding or iron-deficiency anemia. In patients with Crohn's disease, the method may be helpful in establishing or ruling out the diagnosis.

Integrative plasmid vector for constructing single-copy reporter systems to study gene regulation in Rhizobium meliloti and related species

The integrative system of phage 16-3 of Rhizobium meliloti 41 was shown to function in several bacterial species belonging to the Rhizobium, Bradyrhizobium, Azorhizobium, and Agrobacterium genera. It might also function in many other bacterial species provided that both the target site (attB) and the required host factor(s) are present. Here we report on the construction of a new integrative vector that can be utilized in gene regulation studies. It provides an opportunity to create a single-copy set-up for characterizing DNA-protein interactions in vivo, in a wide range of bacteria. To demonstrate the usefulness of the vector, transcription repression by binding of the C repressor protein of phage 16-3 to wild type operators was studied. The assay system provided highly reproducible quantitative data on repression.

Refractive index of NH(4)Cl-H2O as a function of wavelength: the effect of temperature and concentration

The refractive index of NH(4)Cl-H(2)O solutions has been measured over a wavelength range from 496.5 to 690 nm. The NH(4)Cl concentration was varied from 15 to 30 wt. % over a temperature range from 10 to 35 °C. We obtained mathematical equations relating the refractive index to wavelength, temperature, and concentration using the least-squares method. A knowledge of these properties is important for analyzing and modeling the dendritic growth of this system.