TNF-α Inhibitor Treatment in an Ankylosing Spondylitis Patient with Secondary Amyloidosis that Manifest with Diarrhea: A Case Report

Secondary amyloidosis (Amyloid A amyloidosis) occurs when serum amyloid S accumulates in various tissues and organs.It often accompanies chronic inflammatory disease, especially rheumatoid arthritis, as well as ankylosing spondylitis (AS) and Crohn's disease.Although amyloid deposits were reported in 7% of the abdominal fatty tissue samples from AS patients, most of the patients had no symptoms.In a large study, 1.1% of 730 patients with AS were diagnosed with amyloidosis.Most of them showed renal involvement, while none had gastrointestinal symptoms.In South Korea, only a few cases of gastrointestinal involvement of secondary amyloidosis have been reported in AS patients, and there is no report on the effect of a tumor necrosis factor (TNF)-α inhibitor.We report a case of secondary amyloidosis in an AS patient who improved with the TNF-α inhibitor etanercept.(Korean