Cavernous Transformation and Portal Vein Obstruction
- Cavernous transformation: the collection of collaterals that develop around an obstructed vessel
- Portal vein obstruction
- Can occur anywhere along the course of the main portal vein or splenic vein, between the hilum of the spleen and the porta hepatis
- In pediatrics, obstruction is most typically of the portal vein.
- Major cause of prehepatic portal hypertension
- Most children with portal vein thrombosis present between birth and 15 years of age.
- Acute presentation is rare.
- Chronic cases present with complications of portal hypertension.
- Gastrointestinal (GI) bleeding is more typical in patients presenting <7 years of age.
- Splenomegaly in the absence of symptoms is more typical for patients aged 5–15 years.
A genetic basis of this problem has not been identified, although congenital abnormalities of the heart, major blood vessels, biliary tree, and renal system are often found.
- In cirrhosis and hepatic malignancies, the thrombus usually begins intrahepatically and spreads to the extrahepatic portal vein.
- In most other etiologies, the thrombus usually starts at the site of origin of the portal vein.
- Occasionally, thrombosis of the splenic vein propagates to the portal vein, most often resulting from an adjacent inflammatory process (e.g., severe pancreatitis).
- Asymptomatic splenomegaly or upper GI hemorrhage results from extrahepatic portal hypertension.
- Less commonly, ascites or failure to thrive, and portopulmonary hypertension
50% of portal vein obstructions are idiopathic. Identified causes include the following:
- Congenital vascular anomaly
- Portal vein malformation
- Webs or diaphragms within the portal vein
- Clot resulting from a hypercoagulable state
- Clot from other causes:
- Umbilical vein catheterization
- Portal pyelophlebitis
- Intra-abdominal sepsis
- Surgery near the porta hepatis
- Other causes for portal vein obstruction in older children:
- Ascending pyelophlebitis from perforated appendicitis
- Primary peritonitis, cholangitis, and pancreatitis causing a splenic vein thrombosis
- Inflammatory bowel disease
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Cabana, Michael D., editor. "Cavernous Transformation and Portal Vein Obstruction." Select 5-Minute Pediatrics Topics, 7th ed., Wolters Kluwer Health, 2015. Medicine Central, im.unboundmedicine.com/medicine/view/Select-5-Minute-Pediatric-Consult/14148/1.0/Cavernous_Transformation_and_Portal_Vein_Obstruction.
Cavernous Transformation and Portal Vein Obstruction. In: Cabana MDM, ed. Select 5-Minute Pediatrics Topics. Wolters Kluwer Health; 2015. https://im.unboundmedicine.com/medicine/view/Select-5-Minute-Pediatric-Consult/14148/1.0/Cavernous_Transformation_and_Portal_Vein_Obstruction. Accessed June 7, 2023.
Cavernous Transformation and Portal Vein Obstruction. (2015). In Cabana, M. D. (Ed.), Select 5-Minute Pediatrics Topics (7th ed.). Wolters Kluwer Health. https://im.unboundmedicine.com/medicine/view/Select-5-Minute-Pediatric-Consult/14148/1.0/Cavernous_Transformation_and_Portal_Vein_Obstruction
Cavernous Transformation and Portal Vein Obstruction [Internet]. In: Cabana MDM, editors. Select 5-Minute Pediatrics Topics. Wolters Kluwer Health; 2015. [cited 2023 June 07]. Available from: https://im.unboundmedicine.com/medicine/view/Select-5-Minute-Pediatric-Consult/14148/1.0/Cavernous_Transformation_and_Portal_Vein_Obstruction.
* Article titles in AMA citation format should be in sentence-case
TY - ELEC T1 - Cavernous Transformation and Portal Vein Obstruction ID - 14148 ED - Cabana,Michael D, BT - Select 5-Minute Pediatrics Topics UR - https://im.unboundmedicine.com/medicine/view/Select-5-Minute-Pediatric-Consult/14148/1.0/Cavernous_Transformation_and_Portal_Vein_Obstruction PB - Wolters Kluwer Health ET - 7 DB - Medicine Central DP - Unbound Medicine ER -