Case Report Secondary Amyloidosis Presenting as Ischemic Proctitis Saad Hashmi , 1 Assad Munis, 2 Ryan T. Hoff , 2 Hymie Kavin, 2 and Eli D. Ehrenpreis 2 1 Advocate Lutheran General Hospital, Department of Internal Medicine, Park Ridge, IL, USA 2 Advocate Lutheran General Hospital, Department of Internal Medicine, Division of Gastroenterology, Park Ridge, IL, USA Correspondence should be addressed to Saad Hashmi; saad.hashmi@aah.org Received 8 December 2020; Revised 25 March 2021; Accepted 1 April 2021; Published 9 April 2021 Academic Editor: Haruhiko Sugimura Copyright © 2021 Saad Hashmi et al. is is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. A 49-year-old man presented with abdominal pain and rectal bleeding for two days associated with a 50-pound unintentional weight loss. History was notable for hypertension, chronic kidney disease, obesity, gout, and acute cholecystitis status post cholecystectomy. Computed tomography (CT) of the abdomen and pelvis showed rectal wall thickening. Colonoscopy showed proctitis with superficial ulcerations. In the setting of renal insufficiency, malabsorption, and low-voltage QRS complexes on electrocardiogram (ECG), amyloidosis was considered in the differential diagnosis. Rectal and renal biopsies with subsequent retrospective staining of gallbladder tissue confirmed amyloid deposition. Gastrointestinal involvement of amyloidosis is rel- atively uncommon. Particularly, amyloid deposition in the gallbladder and rectum is very rare. e development of AA am- yloidosis in our patient may have been related to gout, obesity, and the presence of a heterozygous complex variant for the MEFV (familial Mediterranean fever) gene. Awareness of this atypical presentation of amyloidosis is important, as additional staining of biopsy samples is necessary, and diagnosis allows for directed treatment. 1. Introduction Amyloidosis is an infiltrative disorder characterized by extracellular deposition of insoluble proteins in various tissues. ese insoluble proteins are folded in such a manner that they cannot be degraded by cellular proteases, resulting in accumulation of amyloid fibrils. Subsequently, the structure and function of organs that contain these de- posited proteins are impaired. e most common form of systemic amyloidosis is primary amyloidosis (AL amy- loidosis), which is caused by immunoglobulin light chain deposition. Secondary amyloidosis (AA amyloidosis) is caused by deposition of serum amyloid A protein (SAA), an acute-phase reactant produced in response to inflammation. us, AA amyloidosis is most often seen in chronic states of inflammation. Secondary amyloidosis commonly affects the kidneys, skin, liver, and spleen. Involvement of the gas- trointestinal (GI) tract occurs in only about 3–8% of all cases of AA amyloidosis. Within the GI tract, amyloid deposits confirmed by histology are most often detected in the small intestine (50%), stomach (44%), colon (32%), esophagus (12%), and rectum (8%) [1]. Gastrointestinal manifestations of amyloidosis include abdominal pain, weight loss, malabsorption, dysmotility, hepatomegaly, splenomegaly, jaundice, and GI bleeding. Amyloid deposition in the GI tract often occurs in the muscularis mucosa in close proximity to blood vessels and nerves. Gastrointestinal bleeding occurs secondary to vas- cular fragility and mucosal ulcerations. Compared with GI amyloidosis, ischemic colitis more often presents with ab- dominal pain associated with GI bleeding and commonly affects areas of the colon that have limited collateralization, rarely affecting regions with dual blood supply, such as the rectum [2]. We report a case of ischemic proctitis as the presentation of secondary amyloidosis. 2. Case Presentation A 49-year-old male presented with two days of rectal bleeding in the setting of two months of acute on chronic diffuse abdominal pain and anorexia. Comorbid conditions included hypertension, obesity, gout, and chronic kidney disease. He admitted to malaise, nausea, and vomiting. e patient’s baseline weight was around 271lbs with a BMI of Hindawi Case Reports in Gastrointestinal Medicine Volume 2021, Article ID 6663391, 4 pages https://doi.org/10.1155/2021/6663391