We present a 33 year-old man with massive upper gastrointestinal bleeding caused by a rare form of segmental portal hypertension. The patient developed a pancreatic abscess, which caused an isolated thrombosis in the splenic vein and the development of pronounced collaterals and bleeding fundus varices. The patient underwent splenectomy and recovered quickly hereafter. The literature is sparse on severe bleeding complications due to acute pancreatitis. The present case emphasizes the importance of recognition of unusual manifestations of common clinical conditions.