An unpredictable gastrointestinal bleeding.

A 65-year-old male complained of persistent melena for 6 days, and displayed anemia symptoms without hematemesis, vomiting, and abdominal distention. He was diagnosed as ruptured aneurysm of aortic sinus Valsalva, and had received coronary artery occlusion 1 month ago. After the operation, he was continually prescribed clopidogrel 75 mg once daily. The laboratory examination showed blood hemoglobin concentration was 60 g/L without other conspicuous abnormality. Unfortunately, neither esophagogastroduodenoscopy (EGD) nor colonoscopy found no obvious bleeding lesions. And abdominal computed tomography angiography (CTA) and enhanced computed tomography (CT) showed no obvious abnormal findings. Moreover, capsule endoscopy revealed small intestinal with mucosal erosion (Figure 1A). After discontinued clopidogrel, blood transfusion, and support therapy, his symptoms was resolved with negative fecal occult blood, continued clopidogrel 75 mg once daily, and uneventfully discharged 1 week later.