Autoimmune disorders of the gastrointestinal tract: Review of radiological appearances

Autoimmune gastrointestinal (GI) disorders comprise a heterogeneous group of diseases with non-specific clinical manifestations. These are divided into primary and secondary. A high index of clinical suspicion complemented with endoscopic and radiological imaging may allow early diagnosis. Due to the relatively low incidence of autoimmune disorder, the imaging literature is sparse. In this review, we outline the pathogenesis, classification, and imaging appearances of autoimmune GI disorders.

Enhancing the Differentiation between Intestinal Behçet's Disease and Crohn's Disease through Quantitative Computed Tomography Analysis

Behçet's disease (BD) behaves similarly to Crohn's disease (CD) when the bowel is involved. Computed tomography enterography (CTE) can accurately show intestinal involvement and obtain body composition data. The objective of this study was to evaluate whether CTE could improve the ability to distinguish between intestinal BD and CD. This study evaluated clinical, laboratory, endoscopic, and CTE features on first admission. Body composition analysis was based on the CTE arterial phase. The middle layers of the L1-L5 vertebral body were selected. The indicators assessed included: the area ratio of visceral adipose tissue (VAT)/subcutaneous adipose tissue (SAT) (VSR) in each layer, the total volume ratio of VAT/SAT, the quartile of VAT attenuation in each layer and the coefficient of variation (CV) of the VAT area for each patient was also calculated. Two models were developed based on the above indicators: one was a traditional model (age, gender, ulcer distribution) and the other was a comprehensive model (age, gender, ulcer distribution, proximal ileum involvement, asymmetrical thickening of bowel wall, intestinal stenosis, VSRL4, and CV). The areas under the receiver operating characteristic (ROC) curve of the traditional (sensitivity: 80.0%, specificity: 81.0%) and comprehensive (sensitivity: 95.0%, specificity: 87.2%) models were 0.862 and 0.941, respectively (p = 0.005).

The treatment principles and targets for intestinal Behcet's disease

Behcet's disease (BD) is a chronic and recurrent systemic vasculitis involving large, medium and small blood vessels as well as arteries and veins. BD with predominant gastrointestinal manifestations is diagnosed as intestinal BD, which is associated with severe complications such as massive gastrointestinal hemorrhage, perforation, and obstruction. Recently, treat-to-target (T2T) strategies have been successfully used in many chronic diseases and been suggested in the management of BD, while there are no related reviews about the global treatment strategy including treatment principles and targets for intestinal BD in detail. Herein, we review the treatment principles from the aspects of departments of Rheumatology and Gastroenterology. In addition, treatment targets of intestinal BD are reviewed from three aspects such as evaluable markers, effective markers and potency-ratio markers. Some definitions and conceptions from inflammatory bowel disease (IBD) bring us reference and enlightenments.

Imaging of intestinal vasculitis focusing on MR and CT enterography: a two-way street between radiologic findings and clinical data

Diagnosis of intestinal vasculitis is often challenging due to the non-specific clinical and imaging findings. Vasculitides with gastrointestinal (GI) manifestations are rare, but their diagnosis holds immense significance as late or missed recognition can result in high mortality rates. Given the resemblance of radiologic findings with some other entities, GI vasculitis is often overlooked on small bowel studies done using computed tomography/magnetic resonance enterography (CTE/MRE). Hereon, we reviewed radiologic findings of vasculitis with gastrointestinal involvement on CTE and MRE. The variety of findings on MRE/CTE depend upon the size of the involved vessels. Signs of intestinal ischemia, e.g., mural thickening, submucosal edema, mural hyperenhancement, and restricted diffusion on diffusion-weighted imaging, are common in intestinal vasculitis. Involvement of the abdominal aorta and the major visceral arteries is presented as concentric mural thickening, transmural calcification, luminal stenosis, occlusion, aneurysmal changes, and collateral vessels. Such findings can be observed particularly in large- and medium-vessel vasculitis. The presence of extra-intestinal findings, including within the liver, kidneys, or spleen in the form of focal areas of infarction or heterogeneous enhancement due to microvascular involvement, can be another radiologic clue in diagnosis of vasculitis. The link between the clinical/laboratory findings and MRE/CTE abnormalities needs to be corresponded when it comes to the diagnosis of intestinal vasculitis.

ECCO Topical Review on Clinicopathological Spectrum and Differential Diagnosis of Inflammatory Bowel Disease

INTRODUCTION

Many diseases can imitate inflammatory bowel disease [IBD] clinically and pathologically. This review outlines the differential diagnosis of IBD and discusses morphological pointers and ancillary techniques that assist with the distinction between IBD and its mimics.

METHODS

European Crohn's and Colitis Organisation [ECCO] Topical Reviews are the result of an expert consensus. For this review, ECCO announced an open call to its members and formed three working groups [WGs] to study clinical aspects, pathological considerations, and the value of ancillary techniques. All WGs performed a systematic literature search.

RESULTS

Each WG produced a draft text and drew up provisional Current Practice Position [CPP] statements that highlighted the most important conclusions. Discussions and a preliminary voting round took place, with subsequent revision of CPP statements and text and a further meeting to agree on final statements.

CONCLUSIONS

Clinicians and pathologists encounter a wide variety of mimics of IBD, including infection, drug-induced disease, vascular disorders, diverticular disease, diversion proctocolitis, radiation damage, and immune disorders. Reliable distinction requires a multidisciplinary approach.

SMALL BOWEL IS LARGELY AFFECTED IN BEHÇET’S DISEASE: A LONG-TERM FOLLOW-UP OF GASTROINTESTINAL SYMPTOMS

ABSTRACT Background Behçet’s disease is a rare immune-mediated disorder that can affect the gastrointestinal tract. The prevalence and extension of small bowel involvement is largely unknown. Objective The aim of this study was to describe the small bowel lesions diagnosed by double-balloon enteroscopy (DBE) and to verify if these findings were associated to the presence of gastrointestinal symptoms and disease activity after long-term follow-up. Methods This study included 19 Behçet’s disease patients who underwent DBE. After a mean follow-up of 15 years the endoscopic findings were associated to the presence of gastrointestinal symptoms, disease activity and current therapy through collection of electronic medical records. Results A total of 63.2% patients were female and the mean age was 37 years at the time of DBE. Mean disease duration at baseline was 24 years. 11 patients had no gastrointestinal symptoms and eight patients presented either abdominal pain, gastrointestinal bleeding or diarrhea. The average procedure time was 1 hour and 30 minutes and the ileum was achieved in all patients but one. Small bowel ulcers were diagnosed in 78.9%, with 63.1% of jejunal involvement. Two patients presented only small bowel edema and two were normal by DBE. Eight patients had concomitant gastric ulcers. Gastrointestinal symptoms prior to DBE were present in 36.8% of the patients and, after follow-up, all of them persisted with some of the symptoms. Bleeding was reported by three patients at baseline and persisted in only one patient. The frequency of treatment with steroids and immunomodulators was 31.6% and 57.9% at baseline, respectively, and 21% in both at the end of the follow-up. No patient was treated with biologics at the time of the DBE procedure and the current rate of biologic use is 21%. Conclusion Small bowel involvement in Behçet’s disease was frequently demonstrated by DBE even in asymptomatic patients. Understanding clinical evolution of the disease over the years and the impact of such diagnosis still represents a challenge, possibly with the need for novel treatment.

Behcet's Disease: An In-Depth Review about Pathogenesis, Gastrointestinal Manifestations, and Management

Background

Behcet's disease (BD) is a complex inflammatory vascular disorder that follows a relapsing-remitting course with diverse clinical manifestations. The prevalence of the disease varies throughout the globe and targets different age-groups. There are many variations of BD; however, intestinal BD is not only more common but has many signs and symptoms.

Summary

BD is a relapsing-remitting inflammatory vascular disorder with multiple system involvement, affecting vessels of all types and sizes that targets young adults. The etiology of BD is unknown but many factors including genetic mechanisms, vascular changes, hypercoagulability, and dysregulation of immune function are believed to be responsible. BD usually presents with signs and symptoms of ulcerative disease of the small intestine; endoscopy being consistent with the clinical manifestations. The mainstay of treatment depends upon the severity of the disease. Corticosteroids are recommended for severe forms of the disease and aminosalicylic acids are used in maintaining remission in mild to moderate forms of the disease.

Key Messages

In this review, we have tried to summarize in the present review the clinical manifestations, differential diagnoses, and management of intestinal BD. Hopefully, this review will enable health policymakers to ponder over establishing clear endpoints for treatment, surveillance investigations, and creating robust algorithms.

Involvement of small bowel in systemic disease: CT and MR imaging finding

Computerized tomography (CT) and magnetic resonance imaging (MRI), particularly MR Enterography, are the standard cross-sectional imaging modalities used to study small bowel involvement in a context of multiorgan disease. Clinical symptoms are generally nonspecific in such cases. Moreover, imaging findings of the different conditions often overlap. However, analysis of the location, distribution of the lesions on the small bowel wall, as well as of the rest of the bowel and of distant organs, may help narrow the spectrum of diagnoses of multiorgan conditions involving both the small bowel and other organs. The purpose of this presentation is to review and illustrate the CT and MRI features of small bowel involvement in systemic disease. Based on the underlying mechanism, we will categorize them as follows: congenital/hereditary, immunologic, infiltrative, vascular, infectious and miscellaneous.

Autoinflammatory diseases in childhood, part 2: polygenic syndromes

Autoinflammatory diseases are a family of disorders characterized by aberrant stimulation of inflammatory pathways without involvement of antigen-directed autoimmunity. They can be further divided in monogenic and polygenic types. Those without an identified genetic mutation are known as polygenic and include systemic-onset juvenile idiopathic arthritis, idiopathic recurrent acute pericarditis, Behçet syndrome, chronic recurrent multifocal osteomyelitis and inflammatory bowel disease among others. Autoinflammatory diseases are characterized by recurrent flares or persistent systemic inflammation and fever, as well as lymphadenopathy and cutaneous, abdominal, thoracic and articular symptoms. Although these syndromes can mimic infections clinically, the inflammatory lesions in autoinflammatory disorders are aseptic. However, because of their infrequency, varied and nonspecific presentation, and the new genetic identification, diagnosis is usually delayed. In this article, which is Part 2 of a two-part series, the authors review the main polygenic autoinflammatory diseases that can be seen in childhood, with special emphasis wherever applicable on imaging features that may help establish the correct diagnosis. However, the major role of imaging is to delineate organ involvement and disease extent.

Malabsorption Syndromes, Vasculitis, and Other Uncommon Diseases

MR enterography is frequently ordered for patients with suspected small bowel disorders. In this article, disease-causing malabsorption, vasculitides, and some of the less common small bowel diseases are reviewed. The clinical presentations, diagnostic criteria, and imaging findings of these diseases are discussed. Because the imaging findings in several small bowel diseases are nonspecific and/or overlap, radiologists must correlate clinical data with imaging to develop a narrower differential diagnosis. The unique or characteristic findings in certain diseases are also emphasized.