Pylephlebitis Secondary to Diverticulitis Diagnosed by Abdominal Ultrasound and Computed Tomography

Pylephlebitis is a rare infection, characterized by non-specific symptoms such as abdominal pain, that often leads to delayed diagnosis, yet it is a severe infection with a high mortality rate. Imaging studies are essential for diagnosis, and contrast-enhanced abdominal CT and abdominal ultrasound are commonly performed. A 51-year-old male was admitted to the hospital with fever and shock. Blood tests revealed liver and kidney dysfunction. Contrast-enhanced computed tomography (CT) is the best modality to demonstrate the portal vein abnormalities and diverticulitis. But plain abdominal CT was performed due to renal impairment, revealing findings suggestive of small bowel diverticulitis and paralytic ileus. Septic shock, presumably caused by bacterial translocation secondary to paralytic ileus, was diagnosed, and meropenem was initiated. Subsequent abdominal ultrasound revealed thrombosis in the portal vein and an abscess in the region suspected of being affected by small bowel diverticulitis. Based on these findings, it was concluded that the patient developed pylephlebitis, septic shock, and paralytic ileus as a result of small bowel diverticulitis and the associated abscess formation. Oral amoxicillin/clavulanate was continued until the abscess resolved. Pylephlebitis often progresses to septic shock, as seen in the present case. In severe cases of intra-abdominal infections, such as diverticulitis, it is necessary to consider the possibility of pylephlebitis and actively perform imaging studies to confirm the diagnosis. Additionally, in cases where contrast-enhanced CT cannot be performed, abdominal ultrasound is useful for diagnosis.