The role of small bowel radiology in the diagnosis and management of Crohn's disease

The value of focally enhanced gastritis in the diagnosis of pediatric inflammatory bowel diseases

BACKGROUND AND AIMS

Focally enhanced gastritis (FEG) has been suggested as a diagnostic marker for patients with Crohn's disease. In this study we evaluated the prevalence of FEG in children with inflammatory bowel diseases (IBD) and assessed the ability of FEG to distinguish IBD from non-IBD patients.

METHODS

A retrospective study of the children who underwent esophagogastroduodenal endoscopy (EGD) during 2004-2011 was performed, after excluding individuals with H. pylori infection and celiac disease. Two groups were studied: patients with IBD (IBD group, n=185) and non-IBD patients who underwent endoscopy of the upper gastrointestinal tract for various abdominal complaints (non-IBD group, n=684). Relation of FEG to age and gender was also assessed.

RESULTS

FEG was found significantly more frequently among children with IBD (35.7% vs 3.4%, respectively, p<0.001). Children with FEG were 15.4 times more likely to have IBD than to belong in the non-IBD group. All types of IBD had significantly higher frequencies of FEG compared to non-IBD individuals (Crohn's disease: 54.1%, ulcerative colitis: 21.6%, IBD unclassified: 18.4%, all three comparisons with the non-IBD group: p-values<0.001). FEG positivity was more common in females compared to males with Crohn's disease and ulcerative colitis and in children younger than 2 years in the IBD-unspecified group. FEG achieved a sensitivity of 35.7% and specificity of 96.6% in distinguishing between IBD from non-IBD patients.

CONCLUSIONS

FEG has significantly higher prevalence in children with IBD, particularly Crohn's disease and can be a valuable supporting finding in cases of indefinite diagnosis.

Contrast-enhanced MR enterography as a stand-alone tool to evaluate Crohn's disease in a paediatric population

AIM

To assess the performance of contrast-enhanced T1-weighted magnetic resonance imaging (MRI) alone in the evaluation of Crohn's disease in comparison to all magnetic resonance enterography (MRE) imaging sequences together in an attempt to suggest limitation of the number of overall unenhanced sequences need for the follow-up evaluation.

MATERIALS AND METHODS

Twenty-five paediatric patients (mean age 14.1 ± 3.7 years, male = 12, female = 13) underwent MRE at 1.5 T for evaluation of Crohn's disease. Two radiologists reviewed only contrast-enhanced T1-weighted images in consensus on the first session. Whole images including unenhanced (steady-state free precession, single-shot fast spin-echo (HASTE), fat-suppressed T2-weighted) and contrast-enhanced T1-weighted sequences were reviewed in consensus during the second session with a 1 month interval, which was used as a reference standard. The readers evaluated the presence or absence of disease in 10 bowel segments in each patient. For the abnormal bowel segments, the readers then evaluated for active versus inactive disease and for the presence or absence of abscess. Sensitivity, specificity, and overall accuracy were calculated for detecting active inflammation.

RESULTS

There were 53/250 bowel segments with active inflammation using the reference standard imaging method. The sensitivity, specificity, and accuracy for diagnosing active inflammation using contrast-enhanced images alone were 83.3%, 86.9%, and 84.9%. In five of the false-positive cases of detecting abscess from contrast-enhanced imaging alone, absence of abscesses was confirmed on the non-fat-suppressed HASTE images.

CONCLUSION

The number of MRE sequences in paediatric Crohn's patients can be decreased while maintaining diagnostic accuracy using contrast-enhanced T1 and non-fat-suppressed HASTE images.

Inflammatory bowel disease in children and adolescents: assessing the diagnostic performance and interreader agreement of magnetic resonance enterography compared to histopathology

RATIONALE AND OBJECTIVES

The purpose of this study was to determine the accuracy of magnetic resonance enterography (MRE) compared to histopathology in the evaluation of pediatric inflammatory bowel disease and to assess interreader reliability for image interpretation.

MATERIALS AND METHODS

All magnetic resonance enterography studies performed for known or suspected inflammatory bowel disease between July 2009 and July 2010 were retrospectively reviewed by two pediatric radiologists. Exams were evaluated for signs of enteric inflammation and extraenteric disease. A five-point, Likert-type scale was used to assess the overall likelihood of active inflammation, with scores ≥ 3 considered positive. Cohen's κ coefficient was calculated to assess interreader agreement. A subset of patients who had undergone ileocolonoscopy or surgery with confirmed histopathology within 45 days of MRE were used to assess the accuracy of MRE for detecting active inflammation in the terminal ileum and large bowel.

RESULTS

A total of 91 magnetic resonance enterography studies were reviewed. Of these, 45 had comparison histopathology within 45 days. The overall sensitivity of MRE for detecting active inflammation compared to ileocolonoscopy was 92% for both readers, while specificity was 100% for reader 1 and 75% for reader 2. Of the individual parameters evaluated, mucosal hyperenhancement and bowel wall thickening were the most sensitive indicators of active inflammation, each having sensitivity of 86% and specificity of 88%. Cohen's κ coefficient was 0.59, indicating moderate agreement between the readers.

CONCLUSIONS

MRE has high overall diagnostic accuracy for detecting active bowel inflammation in pediatric patients compared to ileocolonoscopy and demonstrates moderate interreader reliability.

Single-balloon enteroscopy, magnetic resonance enterography, and abdominal US useful for evaluation of small-bowel disease in children with (suspected) Crohn's disease

BACKGROUND

The usefulness of single-balloon enteroscopy (SBE) has not been evaluated in children with known or suspected Crohn's disease (CD).

OBJECTIVE

The objectives of this study are to evaluate the diagnostic yield of SBE for pediatric CD by comparing it with US and magnetic resonance enterography (MRE).

DESIGN

Single-center prospective study.

SETTING

Tertiary-care referral hospital.

PATIENTS

Between February 2009 and April 2010, 20 pediatric patients (ages 8-18 years) with suspected inflammatory bowel disease (IBD) or with a previous diagnosis of CD with suspected persistent small-bowel disease were enrolled.

INTERVENTIONS

All patients underwent proximal and distal SBE, 17 patients also underwent US combined with Doppler flow measurements, and 18 underwent MRE.

MAIN OUTCOME MEASUREMENTS

The findings of US with Doppler flow measurements and MRE were compared with those with SBE.

RESULTS

The mean patient age was 15.0 years (range 11.3-18 years, 70% male). Of 14 patients with suspected IBD, 8 had a diagnosis of CD made after SBE. Activity in the small bowel was found in 14 patients (70%) with both suspected and previously diagnosed CD. Twelve patients (60%) had small-bowel disease that was out of reach of conventional endoscopy. Three patients (15%) had small-bowel activity solely in the jejunum, which was not detected by either MRE or US.

LIMITATIONS

Single-center study with small sample size.

CONCLUSIONS

SBE can be used in children to accurately assess small-bowel disease and CD. Small-bowel activity may be identified by SBE in some patients in whom it may not be apparent despite use of conventional upper endoscopy, ileocolonoscopy, US with Doppler flow measurements, or MRE.

MR enterography versus capsule endoscopy in paediatric patients with suspected Crohn's disease

OBJECTIVE

The aim of this prospective study was to compare the diagnostic yield of MR enterography (MRE) with small-bowel capsule endoscopy (SBCE) in paediatric patients with suspected Crohn's disease (CD).

METHODS

Paediatric patients with suspected CD were considered eligible to be enrolled in the study. All patients underwent diagnostic work-up including 1.5-T MRE, ileo-colonoscopy and oesophagogastroduodenoscopy. SBCE was not performed if MRE showed SB stricture or extra-intestinal findings consistent with symptoms.

RESULTS

Sixty consecutive paediatric patients (36 male; average age 14) were enrolled into the study. A positive diagnosis for CD was made in 19 patients, 29 had a negative result and 12 were affected by other gastro-intestinal conditions. SBCE was performed in 37 patients (61.7%); 23 patients were excluded (strictures in five, extra-intestinal findings in 11 and parents' refusal in seven cases). The accuracy, sensitivity, and specificity of MRE and SBCE were 98.3%, 100%, 97.6%, and 91.9%, 90.9%, 92.3%, respectively.

CONCLUSION

Both MRE and SBCE are accurate methods for patients with suspected CD. MRE can be used as a primary imaging technique in suspected CD, in that it allows access to the ileal stricture, which forms a contra-indication for SBCE and provides extra-intestinal information.

Imaging the gastrointestinal tract in 2008

Plain radiographs remain useful in the acute setting. Barium studies continue to be the mainstay investigation of the GI tract but are gradually being superseded by newer techniques for example CTC and small bowel MRI. Further studies are underway to establish the clinical utility of MR and clarify its place in the repertoire of GI imaging studies.

[99mTc-HMPAO-leukocyte-labeled scintigraphy in the detection and follow-up of inflammatory bowel disease]

To assess the clinical value of 99mTc-HMPAO-leukocyte-labeled scintigraphy (LLS) in the detection and follow-up of inflammatory bowel disease (IBD) in the pediatric population, we retrospectively reviewed 33 patients (15 boys; mean age 10.7 +/- 2.2 years) with suspected IBD. A total of 58 examinations were performed: 29 for screening purposes, 23 for follow-up and 6 to detect relapses. LLS was compared with clinical symptoms (PCDAI index), biologic markers of inflammation, barium contrast radiology (BCR; n = 22), sonography (n = 22), colonoscopy (n = 16), and biopsy (n = 13). The final diagnosis was Crohn's disease in 12, ulcerative colitis in 4, and no IBD in 17. In the 17 patients without IBD, LLS was always negative. Among the 16 patients with IBD, LLS showed concordant results with BCR in 7/10 patients, with sonography in 6/11, with colonoscopy in 9/12 and with biopsy in 8/9. The severity of LLS increased with the PCDAI index (p < 0.001), with a positive correlation between the scintigraphic activity index/PCDAI r = 0.76. An increase in the PCDAI index with the severity of LLS (p < 0.001) was also observed in the follow-up, and a weak correlation (r = 0.50) between erythrocyte sedimentation rate/scintigraphic activity index was obtained. In 5 patients with normal biologic markers, LLS detected inflammation. All 6 patients with relapses were symptomatic; 5 had inflammation on LLS and 5 had abnormal biologic markers. In conclusion, LLS can be a useful screening tool in the detection of IBD in children to assess the grade of inflammation and extension of IBD. This technique can detect the presence of inflammation during follow-up and should be performed when relapses are suspected.

Distinct phenotype of early childhood inflammatory bowel disease

GOALS

Our goals were to answer 2 questions: (1) Is the presentation of early-onset inflammatory bowel disease (IBD) similar to typical adolescent-onset IBD? (2) Is there variability in familial aggregation in childhood IBD?

BACKGROUND

The phenotype of IBD in children under 5 years of age (early-onset) is poorly defined. Clinical and genetic studies of IBD, however, generally assume the phenotype to be homogenous throughout childhood.

STUDY

We analyzed data from 413 consecutive pediatric IBD outpatients attending our center between 1995 and 2000. Disease type, anatomic distribution, and family history were compared between children presenting before (early-onset) and after the age of five (5 to 15 y).

RESULTS

Disease presentation was predominantly colonic in early-onset IBD, most patients presenting with ulcerative colitis (UC). Isolated colonic disease was most frequent in early-onset Crohn disease (colonic 76.5%, ileocolic 24%) compared with ileocolic disease (ileocolic 45.5%, colonic 26%, ileal 19.4%, proximal 6.3%) in the older age group. First-degree family history was highest in early-onset UC 26% versus 11% in the older UC group.

CONCLUSIONS

We describe a distinct phenotype of early childhood onset IBD, with a strikingly high familial aggregation in UC and greater tendency to present with colonic disease. As more genetic heterogeneity is identified in IBD, careful definition of phenotype is required to identify further susceptibility genes. The early-onset form of UC presents an ideal group for further genetic analysis. These phenotype differences also suggest that treatment and outcome may vary in early-onset childhood IBD; prospective studies are required to confirm this.

Inflammatory bowel disease

Twenty five per cent of inflammatory bowel disease presents in childhood. Growth and nutrition are key issues in the management with the aim of treatment being to induce and then maintain disease remission with minimal side effects. Only 25% of Crohn's disease presents with the classic triad of abdominal pain, weight loss, and diarrhoea. Most children with ulcerative colitis have blood in the stool at presentation. Inflammatory markers are usually although not invariably raised at presentation (particularly in Crohn's disease). Full investigation includes upper gastrointestinal endoscopy and ileocolonoscopy. Treatment requires multidisciplinary input as part of a clinical network led by a paediatrician with special expertise in the management of the condition.

Inflammatory bowel disease in children and adolescents: recommendations for diagnosis--the Porto criteria

Ulcerative colitis and Crohn disease may present before the age of 20 years in 25% to 30% of all patients with inflammatory bowel disease. Reported incidence figures vary considerably depending on the collection of data. Multicenter, multinational collaboration is needed when studying pediatric inflammatory bowel disease. The essential first step is uniformity in the work-up and criteria used for diagnosis. The Porto diagnostic criteria presented here provide the tool that is needed. These criteria are the result of consensus reached by the ESPGHAN inflammatory bowel disease working group. Diagnosis of Crohn disease, ulcerative colitis and indeterminate colitis is based on clinical signs and symptoms, endoscopy and histology and radiology. Every child suspected of inflammatory bowel disease should undergo a complete diagnostic program consisting of colonoscopy with ileal intubation, upper gastrointestinal endoscopy and (in all cases except in definite ulcerative colitis) radiologic contrast imaging of the small bowel. Multiple biopsies from all segments of the gastrointestinal tract are needed for a complete histologic evaluation. A diagnosis of indeterminate colitis cannot be made unless a full diagnostic program has been performed.

Small intestine contrast ultrasonography: an alternative to radiology in the assessment of small bowel disease

BACKGROUND

Radiology and transabdominal ultrasonography (TUS) are used in the evaluation of the small bowel; however, the former technique is limited by radiation exposure, and the latter by its inability to visualize the entire small bowel.

AIM

To evaluate the diagnostic accuracy of small intestine contrast ultrasonography (SICUS) to assess the presence, number, site, and extension of small bowel lesions.

SUBJECTS AND METHODS

TUS, SICUS, and small bowel follow-through (SBFT) were performed in 148 consecutive patients (78 women; age range, 12 to 89 yr), 91 with undiagnosed conditions, and 57 with previously diagnosed Crohn's disease (CD).

RESULTS

In the undiagnosed patients, the sensitivity and specificity of TUS and SICUS were 57% and 100%, and 94.3% and 98%, respectively. In the CD patients, the sensitivity of TUS and SICUS was 87.3% and 98%, respectively. In comparison with SBFT, the extension of lesions was correctly assessed with SICUS and greatly underestimated with TUS. The concordance index between SBFT and SICUS for the number and site of lesions was 1 and 1 (P < 0.001), respectively, in undiagnosed patients, and 0.81 and 0.83 (P < 0.001), respectively, in CD patients. Between SBFT and TUS, the concordance index was 0.28 and 0.27 (not significant), respectively, in undiagnosed patients, and 0.28 and 0.31 (not significant), respectively, in CD patients.

CONCLUSIONS

The diagnostic accuracy of SICUS is comparable to that of a radiologic examination, and is superior to that of TUS in detecting the presence, number, extension, and sites of small bowel lesions. These findings support the use of noninvasive SICUS for an initial investigation when small bowel disease is suspected and in the follow-up of CD patients.

Prospective comparison of small bowel meal with pneumocolon versus ileo-colonoscopy for the diagnosis of ileal Crohn's disease

BACKGROUND AND AIMS

Both endoscopy and barium radiography are used routinely to diagnose terminal ileal (TI) Crohn's disease (CD). A prospective study was undertaken to compare ileoscopy with biopsy to small bowel meal with pneumocolon (SBMP) in patients with suspected TI CD.

METHODS

A cohort of outpatients investigated for diarrhea with features of TI disease underwent SBMP followed by colonoscopy with ileal intubation and biopsy within 21 days. All results were reported in a standardized, sequential format to assign SBMP TI diagnoses by the duty radiologist and by dual reading with consensus, ileoscopy by the attending endoscopist, and ileoscopy with biopsy by a blinded panel of endoscopists and pathologists. Reference standard TI diagnoses were determined by a consensus panel with full access to medical records.

RESULTS

Among 120 subjects, the reference standard TI diagnosis was normal in 47 (39.1%), lymphoid nodular hyperplasia (LNH) in 24 (20.0%), CD in 48 (40.0%), and NSAID enteropathy in 1 (0.9%). Colonoscopy provided TI images and/or biopsies in 97 cases (80.8%), while SBMP provided TI images in 119 (99.1%). When ileoscopy with biopsy succeeded, its accuracy was similar to SBMP with dual reading (89.7%vs 89.9%, p = NS) but superior to SBMP if interpreted only by the duty radiologist (80.0%, p < 0.05). Biopsy improved the accuracy of ileoscopy, while dual reading improved that of SBMP. Both ileoscopy with biopsy and SBMP with dual reading are highly accurate for diagnosing TI CD. Choice of initial test should reflect local expertise and availability, and the likelihood of associated disease in the proximal small bowel or colon.

Combined terminal ileoscopy and biopsy is superior to small bowel follow-through in detecting terminal ileal pathology

BACKGROUND

Several studies have compared small bowel barium examination with ileoscopy in assessment of terminal ileal disease. Some suggest that ileoscopy is superior in detection of terminal ileal disease whereas others suggest similar disease detection rates for both techniques.

AIMS

The aim of this retrospective study was to determine if small bowel follow-through and ileoscopy with terminal ileum biopsy compare favourably at detecting pathology in the terminal ileum.

PATIENTS AND METHODS

All colonoscopies with terminal ileoscopy performed over a 16-month period were reviewed. We determined which of these patients had also had small bowel follow-through studies within 2 weeks of colonoscopy. We compared the diagnoses of terminal ileum pathology using ileoscopy with terminal ileal biopsy versus small bowel follow-through.

RESULTS

Forty-six patients had both terminal ileoscopy with biopsy and small bowel follow-through. In 19 patients, the terminal ileum was abnormal at ileoscopy and/or biopsy but normal at small bowel follow-through. In 27 patients, terminal ileum findings at small bowel follow-through and at ileoscopy and/or biopsy were compatible.

CONCLUSIONS

This study suggests that examination of the terminal ileum by combined ileoscopy and biopsy may be superior to small bowel follow-through at detecting terminal ileal pathology. In our series, many patients received effective treatment that otherwise would not have been offered based on the small bowel follow-through results alone. Using combined ileoscopy and biopsy, microscopic inflammatory changes, otherwise missed without biopsy, can be detected. Retrograde ileoscopy is recommended in patients with a clinical history of organic diarrhoea and/or abdominal pain even in the presence of a normal small bowel follow-through.

Technetium-99m HMPAO-labeled leukocyte imaging compared with endoscopy, ultrasonography, and contrast radiology in children with inflammatory bowel disease

BACKGROUND

The purpose of this study was to evaluate retrospectively the value of leukocyte-labeled scintigraphy, ultrasonography, and contrast radiography compared with endoscopy in children suspected of having inflammatory bowel disease (IBD).

METHODS

Twenty-eight children (17 boys; mean age, 10.2 years) with IBD based on standard colonoscopic, histologic, and radiologic criteria (16 with Crohn's disease, 5 with ulcerative colitis, 5 with nonspecific colitis, I with granulomatous disease, and I with Beh,cet's disease) were included. Endoscopic, ultrasonographic, and contrast radiologic examinations were realized for 28, 23, and 19 children respectively.

RESULTS

Sensitivity and specificity were 75% and 92% for leukocyte-labeled scintigraphy, 39% and 90% for ultrasonography, and 58% and 83% for contrast radiography. The authors noted discontinuous uptake for 14 of 15 true-positive results for patients with Crohn's disease and continuous uptake for 4 of 4 true-positive results for patients with ulcerative colitis. A negative correlation between scan activity index and Lloyd-Still clinical score was found for 11 patients with Crohn's disease (r = -0.77).

CONCLUSIONS

Leukocyte-labeled scintigraphy, a noninvasive and reproducible technique, is a useful tool in the diagnosis and therapeutic strategy of IBD, and provides information on the presence, the intensity, and the extent of the disease, particularly in the terminal ileum. Leukocyte-labeled scintigraphy may not replace colonoscopy with biopsies for diagnosis confirmation. Its reliability seems higher than that of ultrasonography.

Terminal ileal imaging with ileoscopy versus small-bowel meal with pneumocolon

Disease of the terminal ileum can be diagnosed by ileocolonoscopy or barium radiography. We compared the diagnostic accuracy in the terminal ileum of ileocolonoscopy and small-bowel meal with pneumocolon. Consecutive patients during an 18-month period who had both ileocolonoscopy and small bowel meal with pneumocolon were identified and their colonoscopy reports, radiographs, and ileal biopsies reviewed blindly by paired gastroenterologists, radiologists, and pathologists, respectively. A gold-standard diagnosis was determined for each patient by consensus. Of 48 study subjects, 14 (29.2%) had Crohn's disease, 5 (10.4%) had lymphoid nodular hyperplasia, and 29 (60.4%) were normal. The sensitivity for a diagnosis of Crohn's ileitis was 92.9% for ileocolonoscopy and 100% for small-bowel meal, while their specificities were 100% and 97.1% respectively. The gold standard diagnosis confirmed ileocolonoscopic findings in 45 patients (93.8%) and radiographic findings in 42 patients (87.5%). Agreement between ileocolonoscopy and small bowel meal occurred in 39 cases (81.2%). By combining histology with ileocolonoscopy, the sensitivity and specificity could be increased to 100% for all diagnoses. Ileocolonoscopy and small-bowel meal with pneumocolon are complementary techniques for imaging the terminal ileum. A prospective comparative trial is now needed to more objectively assess their accuracy, cost effectiveness, and adverse effects.