Clinical presentation

A 43-year-old patient was referred to our gastroenterology department with haematochezia. Prior to admission to our unit, the patient experienced two episodes of similar rectal bleeding in 1996 and 1997 (the first one after treatment with non-steroidal anti-inflammatory drugs) explored each time unsuccessfully by upper gastrointestinal endoscopy and colonoscopy. He had no other particular medical history. Upon admission, the patient was pale and asthenic. Examination of the abdomen was normal. Blood testing before transfusion showed: haemoglobin, 8.3 g/dl; leucocytes, 8.0×10^{9 …}