Dr varsha v s, Dr Bhanu V Pillai(Paed Gastro
Dr C Jayakumar
Three and half year old male born at 32 weeks presented with fever and dysuria
Clinical Status:
Child has stable vitals and PICCLE normal growth parameters
System examination
No encephalopathy, non tender hepatomegaly.
Investigations presence of pus cells in the urine, elevated C-reactive protein (CRP), and neutrophilic leukocytosis.
Ultrasound incidentally revealed significant liver abnormalities, which led to a diagnosis of Abernathy malformation, specifically Type I.
Key Findings:
Liver Ultrasound: Diffuse altered liver echotexture with multiple nodular lesions, hypertrophy of the left lobe, and hypertrophy of the hepatic artery.
There was also a 5mm shunt between the extrahepatic portal vein and the retrohepatic inferior vena cava (IVC), with the absence of intrahepatic portal vein branches, suggesting a significant portal-systemic shunt.
CT Scan: Confirmed features consistent with Congenital Porto-Systemic Shunt (Abernathy malformation), likely regenerative nodular hyperplasia in the liver.
Cardiac Exam: ECG findings suggested left ventricular hypertrophy (LVH), possibly secondary to increased systemic circulation load due to the shunt.
Parents were counselled regarding the complications and importance of follow up and need for liver transplantation at a later date.
Abernathy Malformation (Congenital Porto-Systemic Shunt):
Discussion: Abernathy malformation is a rare congenital condition that involves an abnormal development of the venous system. This malformation typically affects the portal venous system, leading to an abnormal connection between the portal vein and the systemic venous circulation, passing the liver.
Incidence: The incidence of Abernathy malformation is about 1 in 100,000 to 1 in 200,000 live births, though the true incidence is likely underreported because the condition can be asymptomatic in some individuals.
Types:
Type I: Complete Absence of the Portal Vein
Description: In Type I Abernathy malformation, the portal vein is completely absent. Blood from the intestines and spleen passes the liver entirely and drains directly into the inferior vena cava (IVC) or sometimes the right atrium via a collateral venous system. It can lead to complications like hepatic encephalopathy, variceal bleeding, and liver dysfunction.
Type II: Portal Vein Present but Malformed
In Type II, the portal vein is present but malformed or hypoplastic (underdeveloped). There is an abnormal communication or shunt between the portal system and the systemic circulation, allowing blood to pass the liver but still maintain some portal venous flow.
Type III: Complex Shunt Between the Portal and Systemic Circulations
Description: Type III is a more complex form, where there is a direct shunt between the portal vein and systemic venous system. This type often involves multiple collateral veins or shunts that connect the portal system to the systemic circulation, passing the liver to varying degrees. This form is less common but may result in significant liver dysfunction, variceal bleeding, and other complications due to the irregular and often multiple shunts.
Imaging and Diagnosis:
Ultrasound/Doppler: Can show abnormalities in the portal venous system, including the presence or absence of the portal vein and any abnormal connections.
CT or MRI Angiography: These are more precise methods for visualizing vascular abnormalities, and they can help identify the exact nature of the shunting and any collateral circulation.
Venography: In some cases, venography may be performed to more clearly map out abnormal connections between the portal and systemic vein.
Treatment:
Conservative management: If asymptomatic and keep in follow up.
Surgical Treatment
If conservative management does not adequately control the symptoms or if the patient experiences significant complications then surgery is the main modality.
a) Surgical Shunt Reversal or Redirection:
Goal: The primary goal of surgical intervention is to redirect blood flow back through the liver, preventing the pass of hepatic detoxification and nutrient processing.
Procedure: The abnormal venous shunt is either closed, redirected, or altered to allow blood to flow through the portal vein to the liver. This type of surgery is often reserved for patients with Type I or Type II Abernathy malformation, where the portal vein is absent or malformed.
b) Endovascular Interventions:
For some cases, endovascular techniques (using catheter-based methods) may be employed to close or redirect abnormal venous connections. This is less invasive than traditional surgery and may be an option in cases where the abnormal venous shunt is well defined and accessible.
c) Liver Transplantation:
In severe cases where liver dysfunction liver transplantation may be required.
Prognosis: The prognosis of Abernathy malformation can range from excellent to poor, depending on the type, severity, and timely management. Early diagnosis and intervention significantly improve outcomes, especially for those with severe forms of the disease (Type I and Type III)