Primary systemic amyloidosis: A cause of malabsorption syndrome

PURPOSE: Although malabsorption syndrome is encountered frequently by gener al internists and gastroenterologists and is common to various underlying d isease processes, primary amyloidosis is often overlooked during medical ev aluation. We describe the diagnosis, natural history, and laboratory featur es of a subgroup of patients with primary amyloidosis who presented predomi nantly with gastrointestinal symptoms and with evidence of a malabsorption syndrome. SUBJECTS AND METHODS: We reviewed all patients diagnosed with amyloidosis a nd malabsorption syndrome who had been seen at the Mayo Clinic from 1960 th rough 1998. Nineteen patients with small bowel biopsy results showing prima ry amyloid and with laboratory evidence of a malabsorption syndrome were st udied. RESULTS: The most common symptoms were diarrhea or steatorrhea in 95% of pa tients (n = 18), anorexia in 42% (n = 8), and dizziness in 32% (n = 6). The most common signs included weight loss in all 19 patients, with a median w eight loss of 30 pounds (range, 2 to 134 pounds) and hypotension or orthost atic changes in 10 patients (53%). The median time from symptom onset to di agnosis was 7 months. Most patients had evidence of amyloid involvement of other organs. Only 3 patients (16%) were diagnosed correctly upon initial p resentation. Serum or urine protein electrophoresis results were positive i n 95% of patients (n = 18). Median survival was I I months from histologic diagnosis. CONCLUSIONS: Primary systemic amyloidosis should be considered in the diffe rential diagnosis of malabsorption syndrome. All patients over 30 years of age with a malabsorption syndrome should have screening serum and urine imm unofixation before undergoing a small bowel biopsy. (C) 2001 by Excerpta Me dica, Inc.