Secondary Amyloidosis Presenting as Ischemic Proctitis

Abstract

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 relatively uncommon. Particularly, amyloid deposition in the gallbladder and rectum is very rare. The development of AA amyloidosis 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.

Gastric, Colonic, and Rectal Amyloidosis in the Setting of Familial Mediterranean Fever: A Unique Cause of Intractable Diarrhea

“…GI amyloidosis often presents as recurrent abdominal pain, nausea, vomiting, weight loss, diarrhea, constipation, bleeding, fecal incontinence, dysphasia [ 7 , 10 , 11 ], or hepatomegaly [ 12 ]. Gut involvement occurs in 3–8% of all cases of secondary amyloidosis cases [ 5 ].…”

“…Intractable diarrhea is the most common symptom in GI amyloidosis cases [ 5 , 11 ]. Typically postprandial, the diarrhea is often watery.…”

“…Rarely, secondary amyloidosis can manifest as lower GI bleeding, mainly in the setting of tissue ischemia. Parts of the GI tract without a collateral blood supply are the most affected [ 5 ]. Hashmi et al [ 5 ] presented an interesting case of rectal proctitis as a unique complication of secondary amyloidosis.…”

“…Parts of the GI tract without a collateral blood supply are the most affected [ 5 ]. Hashmi et al [ 5 ] presented an interesting case of rectal proctitis as a unique complication of secondary amyloidosis. Amyloid deposition predisposes patients to intestinal ischemia, which can cause mucosal ulcerations and vascular fragility [ 5 ].…”

“…The production of inflammatory markers, such as IL-1 and IL-18, results in serositis [ 1 ]. Recurrent FMF attacks lead to continued tissue deposition of serum amyloid A (SAA) protein, an acute-phase reactant [ 4 , 5 ]. SAA protein deposition in the gut causes gastrointestinal (GI) amyloidosis, a rare yet severe complication that often presents as chronic diarrhea and recurrent abdominal pain [ 4 , 6 ].…”