[Clinical decision making in family practice. A patient with abdominal pain and chills].

An 82-year-old man was admitted because of abdominal pain and a shaking chill. His medical history revealed ileocecal resection because of ileitis associated with a Yersinia infection 3 years before admission. One year later he was readmitted because of bowel obstruction due to recurrent ileitis. He was treated with trimethoprim-sulfamethoxazole for two weeks because of positive serological tests for Yersinia and made a full recovery except for chronic diarrhoea. On the current admission, stool cultures yielded Campylobacter upsaliensis. Further analysis showed severe non-specific ulcerative ileitis without colitis. A diagnosis of Crohn's disease was made. The patient was treated with prednisone and mesalazine and made a full recovery. The chronic diarrhoea disappeared. The course was complicated by a cerebro-vascular thrombosis and severe thrombocytosis due to polycythaemia vera. Treatment with hydroxyurea was effective in lowering the thrombocyte count.