Advances in Radiologic Evaluation of Small Bowel Diseases:

Cross-sectional imaging: current status and future potential in adult celiac disease

Celiac disease (CD), triggered by exposure to gluten in genetically susceptible individuals, is an immune-mediated small bowel disease affecting about 1% of the population worldwide. But the prevalence of CD varies with age, sex, and location. A strict gluten-free diet remains the primary treatment for CD, currently. Most of patients with CD respond well to gluten-free diet with good prognosis, while some patients fail to get symptomatic relief or histological remission (e.g., nonresponsive or refractory CD). Because of heterogeneous clinical appearance, the diagnosis of CD is difficult. Moreover, malignant complications and poor outcomes accompanied with refractory CD present great challenges in disease management. Over the past three decades, cross-sectional imaging techniques (computed tomography [CT] and magnetic resonance imaging [MRI]) play an important role in small bowel inflammatory and neoplastic diseases. Compared with endoscopic techniques, cross-sectional imaging permits clearly presentation of both intraluminal and extraluminal abnormalities. It provides vascular and functional information, thus improving the possibility as diagnostic and follow-up tool. The value of cross-sectional imaging for patients with suspected or confirmed CD has been gradually demonstrated. Studies revealed that certain features suggested by cross-sectional imaging could help to establish the early diagnosis of CD. Besides, the potential contributions of cross-sectional imaging may lie in the evaluation of disease activity and severity, which helps guiding management strategies. The purpose of this review is to provide current overviews and future directions of cross-sectional imaging in adult CD, thus facilitating the understanding and application in clinical practice. CLINICAL RELEVANCE STATEMENT: In this review, we systematically summarized the existing knowledge of cross-sectional imaging in adult CD and analyzed their possible roles in clinical practice, including disease diagnosis, complication identification, treatment evaluation, and prognostic prediction. KEY POINTS: • Regarding a condition described as "celiac iceberg", celiac disease remains underdiagnosed and undertreated. • Cross-sectional imaging is helpful in clinical management of celiac disease, including disease diagnosis, complication identification, treatment evaluation, and prognostic prediction. • Cross-sectional imaging should be considered as the valuable examination in patients suspected from celiac disease.

Detection of intramural fat accumulation by 3D-Dixon-Caipirinha-Vibe and the contribution of this technique to the determination of the chronicity of Chron's disease

OBJECTIVES

In this study; we aimed to evaluate the efficacy of the 3D-Dixon-Caipirinha-Vibe fat images in detecting intramural fat accumulation (IFA) and contributions of 3D-Dixon-Caipirinha-Vibe in the management of patients with Chron's disease.

METHODS

Eighty-five patients who had a 3-tesla MR enterography (MRE) with the 3D-Dixon-Caipirinha-Vibe technique were included. Wall thickness, ADC-value, intramural edema, presence/extension of IFA, and contrast-material enhancement of the affected segments were examined. Findings of MRE were compared statistically with clinical, laboratory, endoscopy, and pathological exams.

RESULTS

The presence of IFA was more common in patients with chronic active and chronic inflammation than only active inflammation and normal cases. Patients with IFA had a longer disease duration than patients without IFA. IFA-containing segment lengths of patients with chronic active inflammation and chronic inflammation were found to be longer than those with active inflammation. It was found that patients whose pathology results were reported as active inflammation contained less IFA than patients with chronic inflammation.

CONCLUSIONS

The presence of IFA is strongly related to chronicity. 3D-Dixon-Caipirinha-Vibe is a fast, easy, and useful method for detecting IFA and evaluating Chron's disease.

Plasma citrulline is not a biomarker for intestinal adaptation in short bowel syndrome, studied in piglets: a model for human neonates

BACKGROUND

There are no in vivo methods to measure adaptation in neonatal short bowel syndrome (SBS). We evaluated citrulline (Cit) levels in neonatal piglet surgical models of SBS.

METHODS

Piglets underwent 75% mid-intestinal resection with jejunoileal anastomosis (JI), 75% distal resection of ileum with jejunocolic anastomosis (JC) or sham surgery. Jugular and gastric catheters were inserted for parenteral and enteral nutrition. On D7, small intestine length and weight were measured, jejunum collected for histopathology and Cit level determined.

RESULTS

JI (n = 5) compared to JC (n = 5) had increased small intestinal length (JC - 17.5 cm; JI +22.0 cm; p = 0.02) and mass (JC 43.1 mg/cm/kg; JI 51.3 mg/cm/kg; p = 0.02), while Cit did not differ (JI 801.0 µM; JC 677.7 µM; p = 0.90). Including non-resected shams (n = 4), Cit correlated with length (R² = 0.48; p = 0.006), but not for SBS alone (R² = 0.11; p = 0.4), mass (R² = 0.05; p = 0.5). A second experiment compared change in Cit levels from baseline to D7. Levels declined in sham (n = 8) and JC (n = 10) (sham - 110.1 µM; JC - 56.6 µM; p = 0.17), regardless of intestinal lengthening (sham 29.9 cm; JC - 10.4 cm; p = 0.002).

CONCLUSION

Citrulline levels predict large differences in intestinal length and 'identify' SBS. However, citrulline cannot discriminate between adaptation in JI and JC, nor predict intestinal lengthening.