Effective, safe and efficient porcine model of Forrest Ib bleeding gastric and colonic ulcers.

BACKGROUND: Developing effective gastrointestinal (GI) bleeding animal models is necessary to advance endoscopic hemostasis methods and train endoscopists on their use. Our aim, therefore, was to develop an effective and safe porcine GI bleeding model in the stomach and colon of large and small-sized oozing-type ulcers. METHODS: Gastric and colonic bleeding ulcers were created using either a hybrid endoscopic submucosal dissection (ESD) technique or a cap-assisted endoscopic mucosal resection (EMR-C) technique in 14 pigs. Prior to ulcer creation, animals were treated with either oral apixaban or intravenous (IV) unfractionated heparin anticoagulation in combination with clopidogrel and aspirin. The primary outcome was the technical success of inducing oozing-type Forrest Ib bleeding ulcers. Secondary outcomes included ulcer diameter, number, creation time and the number of complications associated with each technique. RESULTS: Using hybrid ESD and IV heparin anticoagulation, bleeding was observed in 21/23 (91.3%) gastric ulcers and 6/7 (85.7%) colonic ulcers created. The mean diameter and ulcer creation time were 2.3 ± 0.3 cm and 5.3 ± 0.5 min, respectively, for gastric ulcers and 2.2 ± 0.4 cm and 4.06 ± 0.6 min, respectively, for colonic ulcers. Using EMR-C and IV heparin anticoagulation, bleeding was observed in 14/15 (93.3%) gastric ulcers and 6/6 (100%) colonic ulcers created. The mean diameter and ulcer creation time were 0.8 ± 0.2 cm and 2.1 ± 0.5 min, respectively, for gastric ulcers and 0.7 ± 0.2 cm and 1.7 ± 0.3 min, respectively, for colonic ulcers. None of the ulcers created in animals anticoagulated with apixaban developed bleeding. None of the 14 pigs developed any complications. CONCLUSION: We have demonstrated the effectiveness and safety of a porcine GI bleeding model utilizing IV heparin anticoagulation and either hybrid ESD or EMR-C techniques to create oozing-type bleeding ulcers in the stomach and colon with customizable size.

Cyclosporine-Induced Kaposi Sarcoma in a Patient With Ulcerative Colitis.

Kaposi sarcoma (KS) is an angioproliferative neoplasm associated with human herpesvirus-8. Gastrointestinal KS has been well documented in immunosuppressed solid organ transplant patients, with only 26 iatrogenic cases published in patients with inflammatory bowel disease. We report a 24-year-old patient with ulcerative colitis, maintained on cyclosporine for 2 years, who presented with watery, nonbloody diarrhea and weight loss. Colonoscopy revealed human herpesvirus-8-positive hemorrhagic nodules throughout the colon and terminal ileum, with diffuse lymphadenopathy on computed tomography consistent with KS. As gastrointestinal KS may present with symptoms that mimic inflammatory bowel disease, it is critical to maintain suspicion in patients on prolonged immunosuppression to reduce complications.