Characteristics of small bowel injury in symptomatic chronic low-dose aspirin users: the experience of two medical centers in capsule endoscopy

The antithrombotic effects of low-dose aspirin (LDA) are well established, and it is used for primary and secondary prevention of cardiovascular events. However, the small intestinal toxicity of LDA remains unclear. The aim of this study was to review the characteristics of small bowel injury in long-term LDA users with capsule endoscopy (CE). We retrospectively reviewed all chronic LDA users (> 3 months) who underwent CE for suspected small bowel diseases from May 2004 to May 2008 at two medical centers. At our institutions, a total of 22 patients (13 males and 9 females, mean age 66.3 years) taking LDA underwent a CE examination. The indications for CE were obscure gastrointestinal bleeding in 21 patients and 1 patient who had abdominal pain. Twenty-one patients (95.5%) had some small bowel mucosal injury. Small bowel erosions were identified in 14 patients (63.6%). This enteropathy was characterized by multiple petechiae, loss of villi, erosions, and ulcers with round, irregular, and punched-out shapes. Two patients had circumferential ulcers with stricture. In most patients, small bowel lesions were multifocal and were evenly distributed in the small bowel. No patients failed to pass the capsule. This is the first CE report that has studied the characteristics of small bowel injury in chronic LDA users. CE is useful to diagnose small bowel enteropathy associated with LDA.