Department of Digestive Tract Diseases, Medical University of Lodz, Poland.
Department of Hematology, Transplantation and Internal Medicine, University Clinical Center of the Medical University of Warsaw, Poland.
Adv Clin Exp Med. 2021 May;30(5):563-570. doi: 10.17219/acem/133521.
Amyloidosis is a heterogeneous group of diseases in which the extracellular deposition of abnormal fibrillar proteins disrupts tissue structure and function. Intestinal involvement is a very rare manifestation of amyloidosis compared to the most affected organs, the heart and kidneys. Damage of the gastrointestinal tract may be the only manifestation of amyloidosis, or - more often - is a component of the involvement of several organs in systemic amyloidosis. Any part of the digestive tract can be involved; however, the small bowel is the most affected part, followed by the colon. Intestinal amyloidosis is characterized by a heterogeneous clinical picture, with weight loss, chronic diarrhea, abdominal pain, intestinal bleeding, or pseudo-obstruction. Endoscopic findings are characterized by a fine granular appearance, erosions, ulcerations, mucosal friability, multiple protrusions, or tumor-like lesions. Pathologic examination allows for a definitive diagnosis using Congo red staining and a positive sample with apple-green birefringence. The disease can easily be misdiagnosed with several other diseases of the digestive tract and lead to diagnostic challenges in clinical practice. Further, the amyloid colonic deposition may mimic inflammatory bowel disease, malignancy, ischemic colitis, and collagenous colitis. Therefore, gastroenterologists need to include amyloidosis in their diagnostic work-up.
淀粉样变性是一组异质性疾病，其中异常纤维蛋白的细胞外沉积破坏组织结构和功能。与受影响最严重的器官（心脏和肾脏）相比，肠道受累是淀粉样变性的一种非常罕见的表现。胃肠道的损伤可能是淀粉样变性的唯一表现，或者更常见的是全身性淀粉样变性累及多个器官的组成部分。消化道的任何部位都可能受累；然而，小肠是最受影响的部位，其次是结肠。肠淀粉样变性的临床特征表现多样，包括体重减轻、慢性腹泻、腹痛、肠道出血或假性肠梗阻。内镜检查的特征是出现细颗粒状外观、糜烂、溃疡、黏膜脆弱、多发性突起或肿瘤样病变。通过刚果红染色和具有阳性苹果绿双折射的样本进行病理检查可做出明确诊断。该疾病很容易与其他几种消化道疾病误诊，导致临床实践中的诊断挑战。此外，结肠的淀粉样物质沉积可能类似于炎症性肠病、恶性肿瘤、缺血性结肠炎和胶原性结肠炎。因此，胃肠病学家需要将淀粉样变性纳入其诊断检查中。
