History and clinical findings: A 30-year-old male was transferred to the intensive care unit with worsening sepsis of unknown origin and a known history of Crohn's disease. The patient presented with a five-day history of nausea, fever, and serous diarrhea. Clinical examination of the abdomen was unremarkable except for mild epigastric pain on palpation.
Investigations: Computed tomography (CT) of the abdomen revealed gas within the intrahepatic branches of the portal venous system, thickening of the wall of the neoterminal ileum, and mild ascites. In addition, ultrasonography showed acute thrombosis of the portal vein and the superior mesenteric vein. No wall perfusion was seen in either the neoterminal ileum or the ascending colon on color Doppler sonography.
Diagnosis, treatment and course: Based on the combination of portal vein thrombosis along with venous gas in the portal venous system and absence of intestinal perfusion, the diagnosis of pylephlebitis with septic shock was suspected and a laparotomy was performed. Intraoperative exploration revealed phlegmonous terminal ileitis, a significant amount of cloudy fluid, and thrombosis of the mesenteric vein. A right-sided hemicolectomy with ileotransversostomy was performed. Histologic examination confirmed Crohn's disease that was associated with vasculitis and, in particular, with thrombophlebitis and subsequent transmural bowel necrosis. Antibiotic and anticoagulation therapy was resumed without further complications.
Conclusion: In the differential diagnosis of sepsis, especially in combination with abdominal pain or gas in the portal venous system, pylephlebitis should be taken into account. Because of the high mortality, immediate further diagnostic testing and appropriate therapy of this rare diagnosis are necessary.