Small-Bowel Obstruction due to AA Amyloidosis in Presumed Extrapulmonary Tuberculosis

ABSTRACT AA amyloidosis is rare in resource-rich settings, but remains prevalent in regions with untreated infection, particularly tuberculosis. We describe a case in Australia of a 68-year-old Somali-born woman with recurrent small-bowel obstruction, weight loss, and retroperitoneal lymphadenopathy. While colonoscopy was macroscopically normal, small-bowel biopsies revealed Congo red-positive AA amyloidosis. Lymph-node biopsy showed histiocytes with granulomatous inflammation, and tuberculosis testing was negative. Given epidemiologic factors and chronic inflammation, culture-negative tuberculosis with AA amyloidosis sequelae was presumed. Empirical tuberculous treatment led to clinical improvement and resolution of PET-avid lymphadenopathy, highlighting an unusual case of infiltrative small-bowel disease.