[Marked PT-INR prolongation associated with appetite loss due to urinary tract infection in a late elderly case with chronic atrial fibrillation].

An 80-year old woman presented with macroscopic hematuria on June 4(th), 2008. She had been suffering from general malaise and appetite loss since about 10 days previously. She had received anticoagulant therapy with warfarin due to chronic atrial fibrillation and PT-INR was well controlled between 1.