Role of computed tomography enterography/magnetic resonance enterography: is it in prime time?

Imaging in discriminating intestinal tuberculosis and Crohn's disease: past, present and the future

Introduction: Intestinal tuberculosis (ITB) and Crohn's disease (CD) have similar clinical presentation, but require different treatment approaches. Despite advances in various endoscopic, imaging, microbiological, and histological techniques, the differentiation of these two entities is often difficult. Newer radiological and image acquisition modalities have now become indispensable tools for evaluation of these two diseases.Areas covered: This review summarizes the currently available literature on various radiological investigations to differentiate ITB from CD. This review also enumerates the newer modalities in image acquisition techniques and their potential role for differentiating these two diseases. At present abdominal computed tomography (CT) scan is used as a first line investigation for differentiating ITB from CD. Magnetic resonance imaging (MRI) is preferred in pediatric patients and for follow-up studies.Expert opinion: Role of newer modalities like contrast enhanced abdominal ultrasound, perfusion CT, advanced MRI and positron emission tomography (PET) is evolving and requires further exploration. Till further robust studies are available, differentiation between ITB and CD requires use of a combination of clinical, endoscopic, serological, histological, and radiological parameters rather than relying on a single test.

Indian guidelines on imaging of the small intestine in Crohn's disease: A joint Indian Society of Gastroenterology and Indian Radiology and Imaging Association consensus statement

The Indian Society of Gastroenterology (ISG) Task Force on Inflammatory Bowel Disease and the Indian Radiological and Imaging Association (IRIA) developed combined ISG-IRIA evidence-based best-practice guidelines for imaging of the small intestine in patients suspected to have or having Crohn's disease. The 29 consensus statements, developed through a modified Delphi process, are intended to serve as reference for teaching, clinical practice, and research.

Imaging of the small intestine in Crohn's disease: Joint position statement of the Indian Society of Gastroenterology and Indian Radiological and Imaging Association

The Indian Society of Gastroenterology (ISG) Task Force on Inflammatory Bowel Disease and the Indian Radiological and Imaging Association (IRIA) developed combined ISG-IRIA evidence-based best-practice guidelines for imaging of the small intestine in patients with suspected or known Crohn's disease. These 29 position statements, developed through a modified Delphi process, are intended to serve as reference for teaching, clinical practice, and research.

The effect of without using anisodamine during CT enterography on image quality, diagnostic performance and latent side effects

OBJECTIVE

To examine whether no anisodamine injection before CTE was feasible without impairing image quality and diagnostic performance.

MATERIALS

The change of mural thickness and luminal diameter were compared between using and no using anisodamine. The diagnostic performance of small-bowel disease was analyzed and compared.

RESULTS

No motion artifact was detected in two groups. There was no significant difference regarding the change of luminal diameter and mural thickness (all P>0.05). The diagnostic accuracy of small-bowel disease was no significant difference (P=0.63).

CONCLUSION

Lack of anisodamine injection before CTE did not impair image quality and diagnostic performance compared with CTEs performed with anisodamine injection.

Faecal biomarkers for screening small bowel inflammation in patients with Crohn's disease: a prospective study

BACKGROUND

The value of faecal biomarkers for screening small bowel inflammation in patients with Crohn's disease (CD) remains to be elucidated. This prospective study was to evaluate the utility of faecal biomarkers for detecting small intestinal inflammation.

METHODS

A total of 122 consecutive patients with a diagnosis of CD in the small intestine were screened for eligibility. Computed tomography enterography (CTE) was undertaken to evaluate small bowel inflammation followed by colonoscopy to confirm no large bowel involvement. Seventy eligible patients with inflammation confined to the small intestine were included. Faecal samples were collected for assaying calprotectin, lactoferrin and haemoglobin. For assessing the degree of small bowel inflammation, a semi-quantitative scoring system (CTE0, normal; CTE1, mild; CTE2, moderate; CTE3, severe) was applied.

RESULTS

The median calprotectin, lactoferrin and haemoglobin levels were significantly higher in patients with small bowel inflammation, CTE scores 1-3 (n = 42) versus 0 (n = 28): calprotectin, 330 versus 40 ng/ml, p < 0.0001; lactoferrin, 14 versus 3 ng/ml, p < 0.0001; haemoglobin, 29.5 versus 6.5 ng/ml, p = 0.005. There was a strong positive relationship between the faecal biomarkers and CTE score: calprotectin, p < 0.0001; lactoferrin, p < 0.0001; haemoglobin, p = 0.0004. A cutoff value of 140 ng/ml for calprotectin had a sensitivity of 69% and a specificity of 82% with an area under the receiver operating characteristic curve (AUC) of 0.82 to detect small bowel inflammation (CTE scores 1-3), while lactoferrin 6 ng/ml had a sensitivity of 69% and a specificity of 79% with an AUC of 0.83, and haemoglobin 9 ng/ml showed a sensitivity of 71% and a specificity of 39% with an AUC of 0.70.

CONCLUSIONS

Faecal calprotectin, lactoferrin, and to a lesser degree haemoglobin are relevant biomarkers for screening small bowel inflammation in CD patients without large bowel involvement. Further well-designed large-scale studies in this clinical setting should strengthen our findings.

Value of Computerized Tomography Enterography in Predicting Crohn's Disease Activity: Correlation with Crohn's Disease Activity Index and C-Reactive Protein

Background

The accurate evaluation of Crohn’s disease activity is important for the treatment of the disease and for monitoring the response. Computerized tomography (CT) enterography is a useful imaging modality that reflects enteric inflammation, as well as extramural complications.

Objectives

The aim of this study was to evaluate the correlation between CT enterographic (CTE) findings of active Crohn’s disease and the Crohn’s disease activity index (CDAI) and C-reactive protein (CRP).

Patients and Methods

Fifty CT enterographies of 39 patients with Crohn’s disease in the small bowel were used in our study. The CDAI was assessed through clinical and laboratory variables. Multiple CT parameters, including mural hyperenhancement, mural thickness, mural stratification, comb sign, and mesenteric fat attenuation, were evaluated with a four-point scale. The presence or absence of enhanced lymph nodes, fibrofatty proliferation, sinus or fistula, abscess, and stricture were also assessed. Two gastrointestinal radiologists independently reviewed all CT images, and inter-observer agreement was examined. Correlations between CT findings, CRP, and CDAI were assessed using Spearman’s rank correlation and logistic regression analysis. To assess the predictive accuracy of the model, a receiver-operating characteristic curve analysis for the sum of CT enterographic scores was used.

Results

Mural hyperenhancement, mural thickness, comb sign, mesenteric fat density, and fibrofatty proliferation were significantly correlated with CDAI and CRP (P < 0.05). The binary logistic regression model demonstrated that mesenteric fat density, mural stratification, and the presence of enhanced lymph nodes (P < 0.05) had an influence on CDAI severity. The area under the receiver operating characteristic curve (AUROC) of the CTE index for predicting disease activity was 0.85. Using a cut-off value of 8, the sensitivity and negative predictive values were 95% and 94%, respectively.

Conclusion

Most CTE findings correlated with CDAI and CRP in patients with active Crohn’s disease.

Diagnosis of Small-Bowel Diseases: Prospective Comparison of Multi-Detector Row CT Enterography with MR Enterography

PURPOSE

To prospectively compare the accuracies of computed tomographic (CT) enterography and magnetic resonance (MR) enterography for the detection and characterization of small-bowel diseases.

MATERIALS AND METHODS

The institutional review board approved the study protocol, and informed consent was obtained from all participants. From June 2009 to July 2013, 150 consecutive patients (81 men and 69 women; mean age, 38.8 years; range, 18-74 years), who were suspected of having a small-bowel disease on the basis of clinical findings and whose previous upper and lower gastrointestinal endoscopy findings were normal, underwent CT and MR enterography. Two independent readers reviewed CT and MR enterographic images for the presence of small-bowel diseases, for differentiating between inflammatory and noninflammatory diseases, and for extraenteric complications. The histopathologic findings of surgical (n = 23) and endoscopic (n = 32) biopsy specimens were used as the reference standard; the results of video-capsule endoscopy (n = 36) and clinical follow-up (n = 59) were used only to confirm the absence of small-bowel disease.

RESULTS

MR and CT enterography were successfully performed in all 150 patients. Overall sensitivity, specificity, and accuracy, respectively, in identifying patients with small-bowel lesions were 75.9% (41 of 54), 94.8% (91 of 96), and 88.0% (132 of 150) for CT enterography and 92.6% (50 of 54), 99.0% (95 of 96), and 96.7% (145 of 150) for MR enterography. The sensitivity of MR enterography was significantly higher than that of CT enterography for the detection of both overall small-bowel diseases (P = .0159) and neoplastic diseases (P = .0412) but not for the detection of inflammatory diseases (P > .99) or noninflammatory and nonneoplastic diseases (P = .6171).

CONCLUSION

MR enterography is more accurate than CT enterography in the detection of small-bowel diseases; MR enterography was more accurate in detecting neoplastic diseases in particular.

Value of CT enteroclysis in the diagnosis of Crohn's disease

AIM: To evaluate the value of CT enteroclysis (CTE) in the diagnosis and assessment of Crohn's disease(CD).

METHODS: The clinical and imaging data for 31 patients with CD were retrospectively analyzed. CTE imaging features were compared with erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and results of colonoscopy and single balloon enteroscopy (SBE).

RESULTS: The rate of detection of CD by CTE was 75% in patients with active CD and 66.7% in patients with disease in remission. Imaging findings included intestinal wall thickening in 26 cases (92.9%), mural stratification enhancement in 20 cases (71.4%), lymph node swelling in 20 cases (71.4%), comb sign in 17 cases (60.7%), and intestinal stenosis in 13 cases (46.4%). The detect rate was correlated with disease activity and CRP, and mural stratification enhancement and comb sign were correlated with ESR. CTE features were consistent with colonoscopy results in 11 cases (44.0%); however, 10 cases (40.0%) tested positive by CTE but negative by colonoscopy in founding small bowel lesions. The combined detection rate for CTE and colonoscopy was 92.0%. Twelve patients underwent SBE, and the SBE findings on the location of lesions were completely consistent with those of CTE in all 12 cases.

CONCLUSION: Colonoscopy and CTE can be used to effectively and comprehensively assess CD condition, and CTE is helpful in detection of small intestinal lesions and evaluation of disease activities.