Small Bowel Amyloidosis

Systemic diseases affecting the GI tract: A review of clinical and histopathologic manifestations

A variety of systemic diseases may affect the gastrointestinal (GI) tract. Since the GI tract responds to injury in limited ways, identifying these processes may be challenging, especially on small endoscopic biopsies. This article reviews the clinicopathologic features of commonly encountered systemic diseases affecting the tubular GI tract: sarcoidosis, graft vs. host disease, mast cell disorders, systemic sclerosis, and IgG-4 related disease. In addition, we offer guidance in differentiating them from their mimics.

How the Radiologist Must Reason for a Correct Diagnosis in Patients With Small Bowel Mural Thickening Studied by CT or MRI: A Pictorial Review

Conditions that lead to small bowel mural thickening fall into a broad spectrum of diseases, including inflammatory, infectious, vascular or neoplastic. Computed tomography (CT) and Magnetic Resonance Imaging (MRI), especially CT-enterography and MR-enterography, permit evaluation of both entire small bowel and extraluminal structures. In CT/MR-enterography, the main prerequisite for the correct evaluation of small bowel is to obtain optimal intestinal distension. In fact, most errors are related to poor intestinal distension of the bowel which can lead to interpret as pathological a small bowel segment that is not very distended (false positive), or not to recognize presence of pathology in a collapsed segment (false negative). Once the examination has been performed, the images are analyzed in order to identify the presence of small bowel pathology. Pathology of the small bowel can manifest as endoluminal alteration and/or intestinal wall thickening. Once bowel wall thickening has been identified, the radiologist's first objective is trying to define benign or malignant nature of the alteration, using also patient's history and clinical features. Once the suspicion of benign or malignant pathology has been raised, the radiologist must try to formulate a diagnosis of nature. In this pictorial review we describe how the radiologist must reason for a correct diagnosis by answering a pattern of sequential questions in a patient with suspected small bowel disease studied by CT or MRI.

The 13-year bleed: Exuberant amyloid angiopathies, angiodysplasias, and acquired coagulopathies of the gut

Amyloidosis is a disorder characterized by extracellular deposits of proteins that are prone to aggregate and form insoluble fibrils. Amyloid deposits limited to a single organ or tissue without the involvement of any other site in the body is uncommon. We report a 75-year-old man with previously treated non-Hodgkin’s lymphoma who presented with recurrent gastrointestinal hemorrhage. Histopathology showed amyloid deposition within vascular malformations. His bleeding continued with the cause rooted in the fundamental building blocks—clotting factors. We discuss the interplay of the pathophysiology of lymphoma, amyloidosis, and factor X deficiency in a patient with preexisting angiodysplasias leading to refractory gastrointestinal bleeding. To our knowledge, there are only 3 reported cases of concomitant amyloidosis and angiodysplasia in the colon, and none involving the small bowel.

Unusual case of amyloidosis presenting as a jejunal mass

Amyloidosis constitutes a heterogeneous group of disorders of protein misfolding that can involve different organ systems. The disease can occur either in a systemic or localised manner that is well known to involve the gastrointestinal (GI) tract. GI amyloidosis can present with a wide range of symptoms including diarrhoea, bleeding and obstruction. This case illustrates a patient with localised jejunal amyloid light chain disease that was diagnosed serendipitously during a workup for haematuria. Our patient was otherwise asymptomatic, but this case underscores the importance of considering amyloidosis as a possible cause of isolated masses of the small intestine.

Intestinal involvement in amyloidosis is a sequential process

BACKGROUND

Gastrointestinal amyloidosis causes dysmotility. A comprehensive histological analysis to explain these symptoms is lacking. Therefore, we systematically examined histological features of intestinal dysmotility in patients with AL and AA amyloidosis, compared to controls.

METHODS

Autopsy tissue material from small bowel and colon was used for histological (semiquantitative) evaluation of the mucosa, blood vessels, muscular layers, enteric nervous system (ENS) and the interstitial cells of Cajal (ICC), using hematoxylin and eosin, periodic acid Schiff, Elastic von Gieson and Congo red staining, and immunohistochemistry with α-smooth muscle actin, HuC/D, S100 and CD117 antibodies, according to guidelines of the Gastro 2009 International Working Group.

KEY RESULTS

Amyloid deposits were present in the vascular walls of all amyloidosis patients. In the mucosa, amyloid was found in 67% of AA patients. The muscular layers were involved in 64% of amyloidosis patients, most prominent in AA patients, associated with the presence of polyglucosan inclusion bodies, but not with either abnormal α-actin patterns or fibrosis. Amyloid in the muscularis propria surrounding the myenteric plexus was found, but not inside the myenteric plexus. These deposits might be related to loss of the ICC network, but there was no association with decreased neuronal or nerve fiber density.

CONCLUSIONS & INFERENCES

We hypothesize that intestinal dysmotility in amyloidosis patients is a sequential process: amyloid deposition starts in the vasculature, followed by involvement of the muscular layers, ICC loss, and potentially affect the myenteric plexus. This final stage may be accompanied by clinical symptoms of severe intestinal dysmotility.

Dysphagia unveiling systemic immunoglobulin light-chain amyloidosis with multiple myeloma

Dysphagia is an uncommon presentation of systemic immunoglobulin light-chain (AL) amyloidosis with multiple myeloma (MM). Gastrointestinal (GI) involvement usually manifests with altered motility, malabsorption or bleeding. Furthermore, patients identified with GI amyloidosis, without previous diagnosis of a plasma cell disorder, are extremely rare. We report an elderly woman who presented with acute on chronic cardiac dysfunction, sick sinus syndrome and acute renal failure. While admitted, she developed intermittent dysphagia to both solids and liquids. Oesophagogastroduodenoscopy showed ulcerations of oesophagus and duodenum. Biopsies revealed focal amyloid deposition, stained with Congo red. Renal biopsy revealed amyloid deposition in renal arterioles. She underwent a bone marrow biopsy confirming MM, represented by more than 15% plasma cell population. She was started on treatment for heart failure, induction chemotherapy for MM and percutaneous gastrostomy tube for feeding. However, she continued to deteriorate, eventually opting for hospice, and ultimately died 2 days after discharge from hospital.

Small Bowel Lesions Mimicking Crohn's Disease

PURPOSE OF REVIEW

Not all injuries of the terminal ileum are Crohn's disease. It is the purpose of this review to consider the differential diagnosis of other acute and chronic ileal lesions.

RECENT FINDINGS

The recognition of a granulomatous disease of the terminal ileum, distinct from tuberculosis, dates back over 85 years and perhaps much farther, but over the past decades, many other clinical pathologic entities have been described that are neither tuberculosis nor Crohn's eponymous regional enteritis. In recent years, the catalog of lesions mimicking Crohn's disease of the small bowel and proposals for differential diagnosis and treatment have expanded to include newly reported appendiceal pathology, primary cancers and lymphomas of the intestine, unexpected metastases from distant organs, unusual infections, vasculitides and other ischemic conditions, Behçet's disease, endometriosis, and drug reactions. A diagnosis of Crohn's disease should not be a reflex action in the face of small bowel structural or inflammatory lesions without consideration of pathology in adjacent organs, primary and metastatic lesions of the small intestine, infections, vascular diseases, infiltrative diseases, drug injury, or other "idiopathic" conditions.