Contrast ultrasonography of the normal small bowel

Sonography of Gastrointestinal Tract Diseases: Correlation With Computed Tomographic Findings and Endoscopy

Sonographic evaluation of the gastrointestinal (GI) tract may be difficult because of overlying intraluminal bowel gas and gas-related artifacts. However, in the absence of these factors and with the development of high-resolution scanners and the technical experience of radiologists, sonography can become a powerful tool for GI tract assessment. This pictorial essay focuses on sonographic findings of GI tract lesions compared with endoscopic, computed tomographic, and magnetic resonance imaging findings. Neoplastic and non-neoplastic diseases and postoperative complications are illustrated, and the distinctive sonographic characteristics of these entities are highlighted.

Imaging modalities in pediatric inflammatory bowel disease

PURPOSE OF REVIEW

To review the various imaging modalities in the evaluation of pediatric inflammatory bowel disease (IBD) to determine disease location, clinical phenotype and the severity of disease in order to optimize treatment.

RECENT FINDINGS

Assessment of the extent, location and severity of IBD routinely involves imaging of the gastrointestinal tract. Cross-sectional modalities such as magnetic resonance enterography (MRE) and computed tomography enterography visualize the lumen, transmural involvement, extraintestinal manifestations and may facilitate decision-making in disease management. MRE has evolved as the imaging modality of choice for many pediatric IBD indications because it does not involve exposure to ionizing radiation.

SUMMARY

Advances in imaging modalities have revolutionized the assessment of children with IBD in recent years. Small-bowel follow-through is no longer considered the imaging modality of choice in this setting. Cross-sectional enterography is now preferred because, among other advantages, it can potentially distinguish active inflammation from fibrosis, characterize stricturing and penetrating complications, and diagnose extraintestinal manifestations. Although MRE avoids ionizing radiation exposure, it remains costly. Cross-sectional imaging and endoscopy complement each other in the development of objective measures for the assessment of disease activity and monitoring of response to treatment.

Gut and mesenteric lymph node involvement in pediatric patients infected with human immunodeficiency virus

Background

The gastrointestinal tract is a primary target for human immunodeficiency virus (HIV). HIV infection causes a depletion of CD4+ T-lymphocytes in gut-associated lymphoid tissue and affects gastrointestinal mucosal integrity and permeability. The gastrointestinal tract has also been suggested as the main reservoir of HIV despite highly active antiretroviral therapy (HAART). We performed a prospective case-control study to assess gut involvement in HIV-infected patients, either naïve or on HAART, using noninvasive methods such as bowel ultrasound and fecal calprotectin.

Methods

Thirty HIV-infected children and youth underwent the following tests: CD4+ T-cell count and HIV viral load, fecal calprotectin, and bowel ultrasound, with the latter evaluating bowel wall thickness and mesenteric lymph nodes. Fecal calprotectin and bowel ultrasound were also assessed in 30 healthy controls matched for age and sex. Fecal calprotectin was measured using a quantitative immunochromatographic point-of-care test, and concentrations ranging from 0 to 200 μg/g were considered to be normal reference values in children.

Results

Fecal calprotectin was normal in 29 HIV-infected patients and was not significantly different from controls (mean values 63.8±42.5 μg/g and 68.3±40.5 μg/g, respectively; P=0.419), and did not correlate with HIV viral load, CD4+ T-cell absolute count and percentage, or HAART treatment. No significant changes were found on bowel ultrasound except for enlarged mesenteric lymph nodes, which were observed in seven HIV-infected patients (23.3%) and two controls (6.6%). This finding was significantly correlated with high HIV viral load (P=0.001) and low CD4+ T-cell percentage (P=0.004).

Conclusion

HIV-infected children did not have significant biochemical or ultrasonographic signs of bowel inflammation. A few patients showed enlarged mesenteric lymph nodes, which correlated with uncontrolled HIV infection.

Covered self-expanding stent treatment for anastomotic leakage: outcomes in esophagogastric and esophagojejunal anastomoses

BACKGROUND

Anastomotic leakage of esophagogastric and esophagojejunal anastomoses is a severe complication after esophagectomy and gastrectomy associated with a high mortality. We conducted this non-randomized observational study to evaluate the outcomes and clinical effectiveness of covered self-expanding stents (CSESs) in treating esophageal anastomotic leakage.

METHODS

From 2002 to 2013, consecutive patients with anastomotic leakage after esophagogastrostomy or esophagojejunostomy who received CSESs were analyzed concerning leakage characteristics, leakage sealing rate, success and failure rates of CSES treatment, stent-related complications, and mortality.

RESULTS

In 35 patients, anastomotic leakage originating from 5 cervical esophagogastrostomies, 6 thoracic esophagogastrostomies, 12 mediastinal esophagojejunostomies and 12 abdominal esophagojejunostomies were treated with 48 CSESs (16 fully CSES, 32 partially CSES). Of 35 patients, 24 received one stent, 9 received two consecutive stents, and 2 received three consecutive stents. Stent-related complications occurred in 71 % of patients (25/35). The most frequent complications were leakage persistence (44 %) and stent dislocation (19 %). Sealing of the anastomotic leakage was achieved in 24 (69 %) patients after a median (range) stenting time of 19 (1-78) days. Sealing rates differed significantly with 20 % (cervical esophagogastrostomies), 50 % (thoracic esophagogastrostomies), 92 % (mediastinal esophagojejunostomies) and 67 % (abdominal esophagojejunostomies) of patients (p = 0.023). Moreover, clinical success rates differed among these groups (60 vs. 67 vs. 92 vs. 58 %; p = 0.247). Clinical failure of stent treatment was more likely to be recognized in early postoperative leakage (median postoperative day 3 vs. 8; p = 0.098) compared with successful treatment, whereas no difference for clinical success rates was found comparing leakage ≤ 10 versus >10 mm (68 vs. 64 %; p = 0.479).

CONCLUSION

CSESs are an effective treatment for anastomotic leakage in patients with esophagogastrostomies and esophagojejunostomies. Best results can be achieved in patients with anastomotic leakages following mediastinal esophagojejunostomy, and in leakages occurring after the very early postoperative phase.

Small intestine contrast ultrasonography in pediatric Crohn's disease

OBJECTIVE

To evaluate the diagnostic accuracy of small intestine contrast ultrasonography (SICUS) in pediatric Crohn's disease (CD).

STUDY DESIGN

A total of 51 consecutive patients (median age 15 years; range 3-20, 31 male patients), 21 with suspected and 30 with proven CD, were studied. All patients underwent standard ultrasonography (ie, transabdominal ultrasonography [TUS]), SICUS, small bowel follow-through, and upper and lower endoscopy. SICUS was performed in patients after they ingested an oral contrast solution. TUS and SICUS were compared with small bowel follow-through and endoscopy via use of the final diagnosis as reference standard.

RESULTS

In undiagnosed patients, the sensitivity and specificity of TUS and SICUS in detecting CD small bowel lesions were 75% and 100% and 100% and 100%, respectively. In patients with proven CD, the sensitivity and specificity of TUS and SICUS were 76% and 100% and 96% and 100%, respectively. The agreement (k) with radiology for site of lesions was almost perfect for SICUS (0.93), both for jejunal and ileal lesions, and it was fair (0.40) for jejunal and substantial (0.68) for ileal lesions for TUS. Compared with radiology SICUS correctly assessed the length of lesions, whereas TUS underestimated it (P = .0001).

CONCLUSIONS

The radiation-free technique SICUS is comparable with radiology and more accurate than TUS in assessing small bowel lesions in pediatric CD, mainly in the detection of proximal small bowel disease.

Anti-TNF-alpha treatments and obstructive symptoms in Crohn's disease: a prospective study

BACKGROUND

The development of symptomatic strictures in Crohn's Disease after anti-Tumour Necrosis Factor-α antibodies is undefined.

AIM

To assess, in a prospective longitudinal study, the frequency of sub/obstructions in Crohn's Disease patients after treatment with Infliximab or Adalimumab. Changes of small bowel lesions after these biological therapies were searched by ultrasonography.

MATERIALS AND METHODS

From January 2007 to October 2008, 36 Crohn's Disease patients with no previous sub/obstructions were treated with either Infliximab (n=13) or Adalimumab (n=23) for ≥12months (mean follow-up duration after the first treatment 23.2±6.8months). Small Intestine Contrast Ultrasonography was performed before and after treatment in 19/36 patients. Sonographic parameters included: bowel wall thickness, lumen diameter, bowel dilation and lesion extent.

RESULTS

Sub/obstructions developed in 3/36 patients treated with Infliximab (n=1) or Adalimumab (n=2), all with fibrostricturing Crohn's Disease. Sonographic parameters did not significantly change after treatment.

CONCLUSIONS

Sub/obstructive symptoms may develop in one tenth of Crohn's Disease patients treated with anti-Tumour Necrosis Factor-α antibodies, with no significant sonographic changes of the small bowel lesions.

A plausible explanation for male dominance in typhoid ileal perforation

The phenomenon of consistent male dominance in typhoid ileal perforation (TIP) is not well understood. It cannot be explained on the basis of microbial virulence, Peyer’s patch anatomy, ileal wall thickness, gastric acidity, host genetic factors, or sex-linked bias in hospital attendance. The cytokine response to an intestinal infection in males is predominantly proinflammatory as compared with that in females, presumably due to differences in the sex hormonal milieu. Sex hormone receptors have been detected on lymphocytes and macrophages, including on Peyer’s patches, inflammation of which (probably similar to the Shwartzman reaction/Koch phenomenon) is the forerunner of TIP, and is not excluded from the regulatory effects of sex hormones. Hormonal control of host-pathogen interaction may override genetic control. Environmental exposure to Salmonella typhi may be more frequent in males, presumably due to sex-linked differences in hygiene practices and dining-out behavior. A plausible explanation of male dominance in TIP could include sex-linked differences in the degree of natural exposure of Peyer’s patches to S. typhi. An alternative explanation may include sexual dimorphism in host inflammatory response patterns in Peyer’s patches that have been induced by S. typhi. Both hypotheses are testable.

Development of a numerical index quantitating small bowel damage as detected by ultrasonography in Crohn's disease

Small intestine contrast ultrasonography (SICUS) has emerged as a valuable tool in the detection of intestinal damage in Crohn's disease (CD). Our aim was to develop a numerical index quantitating small bowel damage as detected by SICUS in patients with an established diagnosis of CD. One hundred and ten patients with ileal or ileocolonic CD were prospectively enrolled and followed up for one year. Disease activity was assessed by CDAI and CRP levels. Study variables included bowel wall thickness, lumen diameter, lesion length and number of lesion site. Fistula, mesenteric adipose tissue alteration, abscess and lymphnodes were also considered. Bowel segments were considered as a hollow cylinder. Standardized variations of variables were combined into a statistical and mathematical model to create an algorithm scoring an index value ranging from 0 to 200. Index was subdivided into a severity scale with 5 classes from the lower (A) to the higher score (E). Median lesion index value was significantly higher (p<0.005) in patients with a CDAI>150 and in patients with CRP>5 mg/l (p=0.003). Patients classified in class E and D at SICUS underwent surgery within one year follow up more frequently than those in class C, B and A (p<0.0001). We propose a new index for assessment of small bowel lesions in CD (SLIC: sonographic lesion index for CD) developed by using SICUS. This index may turn ultrasonography in CD from a descriptive qualitative assessment to a quantitative numerical index suitable for comparison studies.

Investigation of small bowel in pediatric Crohn's disease

Investigation of the small bowel has been traditionally a challenge for pediatric gastroenterologists due to its location, anatomical tortuosity, and invasiveness of the available techniques. Recently, there has been a remarkable improvement in imaging and endoscopic tools aimed at exploring successfully the small intestine in inflammatory bowel disease. The former are represented by ultrasonography (either alone or with administration of oral contrast agents) and by magnetic resonance: both have provided accurate methods to detect structural bowel changes, diminishing patient discomfort and precluding radiation hazard. The use of traditional radiologic techniques such as fluoroscopy have been markedly reduced due to radiation exposure and inability to depict transmural inflammation or extraluminal complications. Among the novel endoscopic tools, capsule endoscopy and balloon-assisted enteroscopy have tremendously opened new diagnostic and therapeutic perspectives, by allowing the direct visualization of small intestinal mucosa and, through enteroscopy, histological diagnosis as well as therapeutic interventions such as stricture dilation and bleeding treatment. These endoscopic techniques should always be preceded by imaging of the intestine in order to identify strictures. This review describes the most recent progress with the employment of novel imaging and endoscopic methodologies for investigating the small bowel in children with suspected or established Crohn's disease.

Small intestine contrast ultrasonography (SICUS) for the detection of small bowel complications in crohn's disease: a prospective comparative study versus intraoperative findings

BACKGROUND

In Crohn's disease (CD) patients, small intestine contrast ultrasonography (SICUS) accurately assesses small bowel lesions. Its diagnostic role is not known in the assessment of intraabdominal CD complications. The aim was to assess the value of SICUS to detect intestinal complications in patients with CD.

METHODS

Forty-nine CD patients (21 female, mean age 37.7 years; range 12-78 years) underwent resective bowel surgery and were included in this study. The accuracy of SICUS to preoperatively detect number, site, and length of strictures, fistulas, and abscesses was compared with surgical and pathological findings by kappa statistics.

RESULTS

SICUS identified at least one stricture in 39/40 and excluded it in 9/9 (97.5% sensitivity, 100% specificity, k = 0.93); two or more strictures in 9/12 (75% sensitivity, 100% specificity, k = 0.78). The agreement by k-statistics between SICUS and surgery in identifying proximal and distal small intestine site of stricture was 1 and 0.92, respectively. The extension of strictures was 6.8 ± 5.4 cm at surgery, 6.6 ± 5.4 cm at SICUS (NS). Fistulas were correctly identified in 27/28 patients and excluded in 19/21 patients (96% sensitivity, 90.5% specificity, k = 0.88). Intraabdominal abscesses were correctly detected in 10/10 patients and excluded in 37/39 patients (100% sensitivity, 95% specificity, k = 0.89).

CONCLUSIONS

SICUS is an accurate method for the detection of small intestinal complications in CD. Noninvasive SICUS is valuable as a primary investigative method for evaluating and planning proper treatment in patients with severe CD of the small bowel.

Diagnostic accuracy of small intestine ultrasonography using an oral contrast agent in Crohn's disease: comparative study from the UK

AIM

To evaluate the usefulness of small intestine contrast-enhanced ultrasonography (SICUS) using an oral contrast agent in routine clinical practice by assessing the level of agreement with the established techniques, small bowel follow-through (SBFT) and computed tomography (CT), and diagnostic accuracy compared with the final diagnosis in the detection of small bowel Crohn's disease (CD) and luminal complications in a regional centre.

MATERIALS AND METHODS

All symptomatic known or suspected cases of CD who underwent SICUS were retrospectively reviewed. The level of agreement between SICUS and SBFT, CT, histological findings, and C-reactive protein (CRP) level was assessed using kappa (κ) coefficient. Sensitivity was demonstrated using the final diagnosis as the reference standard defined by the outcome of clinical assessment, follow-up, and results of investigations other than SICUS.

RESULTS

One hundred and forty-three patients underwent SICUS of these 79 (55%) were female. Eighty-six (60%) were known to have CD and 57 (40%) had symptoms suggestive of intestinal disease with no previous diagnosis. Forty-six (55%) of the known CD patients had had at least one previous surgical resection. The sensitivity of SICUS in detecting active small bowel CD in known CD and undiagnosed cases was 93%. The kappa coefficient was 0.88 and 0.91 with SBFT and CT, respectively. SICUS detected nine patients who had one or more small bowel strictures and six patients with a fistula all detected by SBFT or CT.

CONCLUSION

SICUS is not only comparable to SBFT and CT but avoids radiation exposure and should be more widely adopted in the UK as a primary diagnostic procedure and to monitor disease complications in patients with CD.

Intralesional steroid injection after endoscopic balloon dilation in pediatric Crohn's disease with stricture: a prospective, randomized, double-blind, controlled trial

BACKGROUND

Endoscopic balloon dilation (EBD) is an attractive conservative therapy for Crohn's disease (CD) with stricture; however, its long-term efficacy has been questioned because many patients require more dilations or postdilation surgery. Most reports are retrospective, and no pediatric data are available.

OBJECTIVE

To assess the effectiveness of corticosteroid intralesional injection after EBD in preventing stricture recurrence.

DESIGN

Single-center prospective, randomized, double-blind, controlled trial.

SETTING

Tertiary-referral university hospital.

PATIENTS

Between November 2005 and January 2009, 29 pediatric patients with stricturing CD were enrolled.

INTERVENTIONS

Enrolled patients were randomized to receive intrastricture injection of corticosteroid (CS) (n = 15) or placebo (n = 14) after EBD. Patients were followed clinically via small intestine contrast US and intestinal magnetic resonance imaging at 1, 3, 6, and 12 months; all underwent colonoscopy 12 months after dilation.

MAIN OUTCOME MEASUREMENTS

Time free of repeat dilation and time free of surgery in the 2 groups.

RESULTS

One of the 15 patients receiving CS required redilation, whereas the latter was needed in 5 of the 14 placebo patients; surgery was needed in 4 of the placebo patients, but in none of those receiving CS. The 2 groups statistically differed in the time free of redilation (P = .04) as well as for time free of surgery after EBD (P = .02), which were worse in the placebo group compared with the CS group. There were no significant differences in baseline demographics between the 2 groups.

LIMITATIONS

Sample size, participation bias, and short-term follow-up.

CONCLUSION

In pediatric CD with stricture, intralesional CS injection after EBD is an effective strategy for reducing the need both for redilation and surgery.

Endoscopic vs ultrasonographic findings related to Crohn's disease recurrence: a prospective longitudinal study at 3 years

BACKGROUND AND AIMS

Ileocolonoscopy (IC) is the gold standard for assessing Crohn's Disease (CD) recurrence after ileo-colonic resection. In a prospective longitudinal study we compared findings related to CD recurrence when using techniques visualizing either the luminal or the extraluminal surface (IC and small bowel follow through, SBFT vs Small Intestine Contrast Ultrasonography, SICUS).

METHODS

From 2003 to 2008, 25 CD patients undergoing ileo-colonic resection were enrolled. Clinical assessment (CDAI) was performed at 1, 2 and 3 years. IC was performed at 1 (n=25) and 3 years (n=15), SBFT at 2 years (n=21) and SICUS at 1 (n=25), 2 (n=21) and 3 years (n=15). Recurrence was assessed by SBFT and SICUS (bowel wall thickness, BWT) when using IC as gold standard.

RESULTS

At 1 year, all patients were inactive and recurrence was detected by IC in 24/25 (96%) and by SICUS in 25/25 patients. At 2 years, 6/21 patients (29%) were active and recurrence was detected by SBFT in 12/21 (57%) and by SICUS in 21/21 patients. At 3 years, 5/15 patients (33%) were active, IC showed recurrence in 14/15 (93%), and SICUS in 15/15 patients. The endoscopic score at 1 year was higher in patients developing relapse at 2 years (n=5) than in patients maintaining remission (n=10) (median: 4, range 3-4 vs 2, range 0-3; p=0.003). The same finding was not observed by using SICUS (median BWT at 1 year: 5, range 4-7 vs 3.7, range 3.5-6; p=0.19).

CONCLUSIONS

Although IC and SICUS provide a different view of the bowel wall, in experienced hands SICUS provides findings compatible with endoscopic recurrence after ileo-colonic resection for CD. Discrepant findings may be observed in a low proportion of patients with minor lesions related to CD recurrence.

Ultrasonographic detection and assessment of the severity of Crohn's disease recurrence after ileal resection

BACKGROUND

Recurrence and severity of Crohn's disease mucosal lesions after "curative" ileal resection is assessed at endoscopy. Intramural lesions can be detected as increased wall thickness at Small Intestine Contrast Ultrasonography (SICUS).

AIMS

To assess after ileal resection whether: 1) SICUS detects recurrence of Crohn's disease lesions, 2) the intestinal wall thickness measured at the level of ileo-colonic anastomosis predicts the severity of endoscopic lesions, 3) the extension of intramural lesions of the neo-terminal ileum is useful for grading severity of the recurrence, 4) the combined measures of wall thickness of the ileo-colonic anastomosis and of the extension of intramural lesions at level of the neo-terminal ileum may predict the endoscopic Rutgeerts score

METHODS

Fifty eight Crohn's disease patients (M 37, age range 19-75 yrs) were prospectively submitted at 6-12 months intervals after surgery to endoscopy and SICUS for a total of 111 observations.

RESULTS

Six months or more after surgery wall thickness of ileo-colonic anastomosis > 3.5 mm identified 100% of patients with endoscopic lesions (p < 0.0001). ROC curve analysis, combining wall thickness of ileo-colonic anastomosis and the extension of intramural lesions of neo-terminal ileum, discriminated (0.95) patients with, from those without, endoscopic lesions. Performing two multiple logistic regression analyses only wall thickness of ileo-colonic anastomosis and extension of neo-terminal ileum intramural lesions were significantly associated with absence or presence of endoscopic lesions. An ordinal polychotomus logistic model, considering all investigated variables, confirmed that only SICUS variables were associated with endoscopic grading of severity.

CONCLUSIONS

In patients submitted to ileal resection for Crohn's disease non-invasive Small Intestine Contrast Ultrasonography 1) by assessing thickness of ileo-colonic anastomosis accurately detects initial, minimal Crohn's disease recurrence, and 2) by assessing both thickness of ileo-colonic anastomosis and extension of intramural lesions of neo-terminal ileum grades the severity of the post-surgical recurrence.

Ultrasound and inflammatory bowel disease

Transabdominal bowel sonography is a fast, efficient, and cheap way of examining the intestines. It is also virtually hazard-free and well accepted by patients. During the last 20 years, it has been established as a procedure for detecting bowel disease early in the diagnostic workup. Although rather unspecific, the method is sensitive for detection of bowel disease and can be applied to find the extent and location of inflammatory bowel disease. In patients with known ulcerative colitis and Crohn disease, it can also be used for follow-up because it is easily repeatable and radiation-free. Because it can be applied to find both intraluminal and peri-intestinal pathological features, it is a particularly valuable tool for the detection of complications of Crohn disease as stenosis, fistulas, and abscesses. Neither B-mode nor Doppler techniques have been proven obviously useful in categorizing disease activity, but new techniques using intravenous contrast might come closer to solving this question. Finally, recent longitudinal studies using transabdominal bowel sonography show that it can also give important prognostic information and be used for monitoring the effect of therapy.

Hydrosonography of the gastrointestinal tract

OBJECTIVE

Bowel sonography has become accepted as a useful tool in several gastrointestinal disorders. Filling of the gut with echo-poor liquids has been proposed to achieve a detailed evaluation of the bowel. This article refers to a review made concerning the benefits and limits of hydrosonography of the gastrointestinal tract.

CONCLUSION

The use of a luminal contrast agent in bowel sonography may improve results but should be adopted on a case-by-case basis, according to the clinical context and the experience of the sonologist.

Normal small bowel wall characteristics on MR enterography

PURPOSE

To assess the normal small bowel parameters, namely bowel diameter, bowel wall thickness, number of folds (valvulae connivientes) per 2.5 cm (in.), fold thickness and interfold distance per small bowel segment (duodenum, jejunum, proximal ileum, distal ileum and terminal ileum) on MR enterography.

MATERIALS AND METHODS

Between September 2003 and January 2008, 280 MR enterography examinations were performed for investigation of known or suspected small bowel pathology. 120 of these examinations were normal. Sixty-five (m=29, f=36, mean age=34 years, range=17-73 years) of 120 examinations without a prior small bowel diagnosis, with no prior or subsequent abnormal radiology or endoscopy examinations, no prior small bowel surgery and with a minimum 3 years follow-up demonstrating normality were retrospectively evaluated for the described small bowel parameters.

RESULTS

We found the mean diameter of the duodenum to be 24.8mm (S.D.=4.5mm), jejunum to be 24.5mm (S.D.=4.2mm), proximal ileum to be 19.5mm (S.D.=3.6mm), distal ileum to be 18.9 mm (S.D.=4.2mm) and terminal ileum to be 18.7 mm (S.D.=3.6mm). The number of folds per 2.5 cm varied from 4.6 in the jejunum to 1.5 in the terminal ileum. The fold thickness varied from 2.1mm in the duodenum to 1.8mm in the terminal ileum. The small bowel parameters gradually decreased in size from the duodenum to the smallest measurements which were in the terminal ileum. The bowel wall is similar in size throughout the small bowel measuring 1.5+/-0.5mm.

CONCLUSION

These results provide the mean, range of normality and standard deviation of the small bowel parameters per segment on the current population on MR enterography. From our experience, knowledge of these parameters is extremely helpful and essential in the everyday assessment of MR enterography studies.

Effect of infliximab on small bowel stenoses in patients with Crohn’s disease

AIM: To assess prospectively small bowel stenoses in Crohn’s disease (CD) patients treated with infliximab using Small Intestine Contrast Ultrasonography (SICUS).

METHODS: Twenty patients (M 12, age, 42.7 ± 11.8 years), 15 of whom showed obstructive symptoms indicating the presence of small bowel stenosis, and 5 without stenosis, were treated with infliximab (5 mg/kg at wk 0, 2, 6 and 5 mg/kg every 8 wk thereafter) for steroid refractoriness, fistulizing disease, or to avoid high-risk surgery. SICUS was performed at the induction phase and at regular time intervals during the follow-up period of 34.7 ± 16.1 mo (range 7-58). Small bowel stenoses were detected by SICUS, endoscopy and MRI.

RESULTS: In no case was progression of stenoses or the appearance of new ones seen. Of the 15 patients with stenosis, 5 stopped treatment after the induction phase (2 for no response, 3 for drug intolerance, one of whom showed complete regression of one stenosis). Among the remaining 10 patients, a complete regression of 8 stenoses (1 stenosis in 5 patients and 3 stenoses in one patient) was observed after 6-22 infliximab infusions.

CONCLUSION: In patients with CD treated with infliximab we observed: (a) No progression of small bowel stenosis and no appearance of new ones, (b) Complete regression of 1/22 stenosis after the induction phase and of 8/15 (53.3%) stenosis after 6-22 infusions during maintenance therapy.

Small intestinal contrast ultrasonography-based scoring system: a promising approach for the diagnosis and follow-up of celiac disease

BACKGROUND

Small intestinal ultrasonography with anechoic contrast agents (SICUS) has been shown to have a diagnostic accuracy on small bowel morphology similar to X-ray barium follow-through. Although extremely investigated by transabdominal ultrasonography, celiac disease, a common disorder of the small bowel, has been never studied by SICUS.

AIM

To asses SICUS characteristics of celiac disease patients.

PATIENTS AND METHODS

SICUS was performed using PEG 4000 as contrast agent. Twenty-three patients with celiac disease at the first diagnosis were enrolled and 30 healthy volunteers, matched for sex and age, were selected as control group. Celiac disease diagnosis was based on anti-gluten, anti-endomysium, and anti-transglutaminase positivity as well as jejunal histology. The following seven echographic parameters were considered: liquid endoluminal content before contrast, loop diameter, Kerckring's folds, peristaltic waves, ileal jejunalization, mesenteric lymphoadenomegaly, and Doppler resistance index (RI) of mesenteric superior artery. Statistical analysis was performed by Student's t test for unpaired data; one-way analysis of variance was used to correlate echographic and histologic pictures.

RESULTS

Loop diameter, Kerckring's fold number, peristaltic waves, and Doppler RI appeared to be significantly different between celiac disease patients and controls. Additionally, liquid content, ileal jejunalization, and mesenteric lymphoadenomegaly were present only in the celiacs (52.1%, 47.7%, and 95.6%, respectively), but not in controls. Only Doppler RI values significantly correlated with the histologic degree of damage.

CONCLUSIONS

SICUS could be a reliable and noninvasive technique to confirm a diagnosis of celiac disease performed using conventional investigations. The possibility of investigating the whole small bowel and the safety of repeating examinations could be useful in the follow-up of celiac patients.

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.

Crohn's disease: a comparative prospective study of transabdominal ultrasonography, small intestine contrast ultrasonography, and small bowel enema

BACKGROUND

Small intestine contrast ultrasonography (SICUS), when performed after distention of the small bowel lumen with an iso-osmolar polyethylene glycol electrolyte-balanced solution, shows high sensitivity (100%) and specificity (97%) in detecting small bowel abnormalities in patients who have not received a diagnosis but in whom there is a suspicion of intestinal diseases. The diagnostic yield of SICUS remains to be established in detecting small bowel lesions in patients with proven Crohn's disease (CD) in comparison with transabdominal ultrasonography (TUS), and in relationship to the experience of the operator, using small bowel enema (SBE) as the "gold standard."

AIM

The aim of this study was to evaluate the diagnostic value of SICUS, when performed by a sonologist with 1 year of experience, and TUS, when performed by a sonologist with 10 years of experience, compared to SBE in the assessment of the site, extension, and stenosis of small intestinal lesions in CD patients.

PATIENTS AND METHODS

A total of 28 consecutive patients (men, 16; women, 12; age range, 21 to 60 yr) with a diagnosis of CD underwent TUS and SICUS, which were performed by 2 sonologists who were unaware of the radiologic findings, on the same day. SICUS was performed after the ingestion of 375 mL of a polyethylene glycol contrast solution. A standard SBE was performed on a different day by an expert radiologist who was unaware of the sonographic findings.

RESULTS

Sensitivities in the detection of small bowel lesions were 96% for TUS and 100% for SICUS. Compared with SBE, SICUS detected the presence of 4 lesions in the jejunum that had been missed by TUS. The mean (+/-SD) extent of the ileal disease was 22 +/- 12.5 cm when measured during SBE, 14.5 +/- 8.6 cm when measured during TUS, and 19.5 +/- 12.5 cm when measured during SICUS [P = 0.05 (SICUS versus SBE)]. The correlation of the extension of the lesions between SICUS and SBE (r = 0.88) was better than that between TUS and SBE (r = 0.64). The sensitivities of TUS and SICUS in the detection of at least 1 stricture were 76% and 94%, respectively. Sensitivity and specificity in assessing prestenotic dilatation were 50% and 100%, respectively, at TUS, and 100% and 90%, respectively, at SICUS.

CONCLUSION

In inexperienced hands, SICUS is a more accurate technique for assessing CD lesions, and the accuracy is better than that of TUS performed by an expert sonologist. The use of SICUS, instead of SBE, could be indicated for the follow-up of patients with CD.

Intestinal imaging of children with acute rotavirus gastroenteritis

OBJECTIVE

To examine the morphology and motility of the distal small bowel of infants with rotavirus gastroenteritis using non-invasive/non-ionizing imaging technology.

METHODS

Prospective, non-randomized observational study of five infants with symptomatic rotavirus infection. Infants were imaged by real-time magnetic resonance imaging (MRI) and ultrasound within 5 days of onset of gastroenteritis symptoms. Imaging studies were repeated in the convalescent period 5 to 9 weeks later.

RESULTS

Three of five infants had a significant increase in the ileal wall thickness visualized by ultrasound during acute rotavirus infection compared with convalescence. The number and size of mesenteric lymph nodes visualized by ultrasound appeared similar in the acute and convalescent phases, as did peristaltic activity assessed by MRI.

CONCLUSION

Abdominal ultrasound can detect changes in ileal wall thickness in infants with rotavirus infection. These changes may reflect ileal inflammation elicited by viral infection. Such studies may prove useful in evaluating morphologic response to attenuated rotavirus vaccines.

Small intestine contrast ultrasonography (SICUS) in the diagnosis of small intestine lesions

After the ingestion of iso-osmolar polyethylene glycol solution, the small bowel can be visualized on ultrasonography. The aim of this study was to assess sensitivity and specificity of SICUS in diagnosis of small bowel lesions. A total of 53 consecutive patients with suspected intestinal pathology underwent a diagnostic workup, including a small bowel follow-through and SICUS performed by independent operators. The sonologist was unaware of the clinical data. Diagnostic sensitivity and specificity were assessed using radiologic findings. Diagnostic sensitivity of SICUS was 100%, with a specificity of 97%. The concordance index was 0.956 (p < 0.003, kappa statistics) and the conformity between SICUS and radiology was 1. The diagnostic accuracy of SICUS to detect small bowel lesions is comparable to that of small bowel follow-through. Results of this study support the use of noninvasive, widely available, inexpensive, and nondemanding SICUS as an initial investigation in patients with suspected small bowel disease.

Transabdominal ultrasonography of the small bowel after oral administration of a non-absorbable anechoic solution: comparison with barium enteroclysis

AIM

The aim of this study was to determine if oral administration of a non-absorbable anechoic solution conveys any benefit during abdominal ultrasound (US), with special reference to its accuracy.

MATERIALS AND METHODS

Fifty-three adult out-patients scheduled for small bowel barium enema (SBE) were included. The day before SBE all patients underwent abdominal US before and after oral administration of an isotonic non-absorbable electrolyte solution containing polyethylene glycol (PEG-ELS). Sensitivity and specificity were evaluated using SBE as a gold standard.

RESULTS

After ingestion of PEG-ELS satisfactory distension of the intestinal lumen was obtained (11-25 mm) with sequential visualization of jejunoileal loops in 30.9 +/- 17.3 min. In 15 out of 53 cases both US and SBE showed bowel changes characteristic of Crohn's disease. In three out of 53 cases both US and SBE showed neoplasms. In one out of 53 cases US was negative, SBE positive for local nodularity and ulcerations typical of Crohn's disease. In one out of 53 cases US was negative, SBE positive for macronodularity consistent with coeliac disease. In five out of 53 cases US was negative, while SBE was positive for mininodularity expressive of lymphoid hyperplasia. In 28 out of 53 cases both examinations were negative.

CONCLUSION

PEG-ELS administration allows a thorough US investigation of the small bowel, with fair sensitivity (72%) and excellent specificity (100%). False negative findings are mainly due to lymphoid hyperplasia, a feature of uncertain significance in adults.

Recent advances in small-bowel imaging: a review

This review outlines technical advances in imaging of the small bowel. These include enhancement characteristics of normal bowel mucosa in computed tomography, contrast agents in magnetic resonance imaging, contrast ultrasonography, small-bowel transit measurements by radionuclide imaging, and enteroscopy. Subsequently, the application of these in clinical problem areas, including small-bowel obstruction, bleeding, and Crohn and celiac disease, will indicate the excellent potential of computed tomography, magnetic resonance imaging, and enteroscopy in particular.