Transition from aspirin-related upper to Clostridioides difficile-induced lower gastrointestinal bleeding.

Clostridioides difficile infection is a prevalent healthcare-associated infection that can lead to severe gastrointestinal complications, including gastrointestinal bleeding. This case report presents a 77-year-old female with multiple comorbidities, including a history of cerebral infarction, who was on long-term aspirin therapy. She initially presented with melena, suggestive of upper gastrointestinal bleeding. Preliminary treatment with pantoprazole and somatostatin resolved the melena. However, she later developed dark red blood per rectum, indicating a shift to lower gastrointestinal bleeding. Further workup, including abdominal CT, colonoscopy, and fecal antigen testing, supported the diagnosis of C. difficile colitis. She was subsequently treated with vancomycin and metronidazole, which resulted in clinical improvement and ultimately led to her discharge from the hospital. This case emphasizes the importance of considering C. difficile infection in patients with gastrointestinal bleeding who are receiving proton pump inhibitors and somatostatin, particularly those with risk factors for the infection.