What is the management of portal hypertension in children?

Portal Hypertension in Children: Etiology, Clinical Features, Investigations, and Management

Etiology

Portal hypertension in children is most commonly caused by extrahepatic portal vein obstruction (portal vein thrombosis), which differs significantly from adults where cirrhosis predominates. 1, 2

Classification by Anatomic Level

• Prehepatic causes: Portal vein thrombosis (most common in children, accounting for approximately 80% of cases), with identifiable risk factors present in two-thirds of patients including umbilical vein catheterization, intra-abdominal infections, and prothrombotic disorders 3, 1, 2
• Intrahepatic causes: Biliary atresia, congenital hepatic fibrosis, idiopathic non-cirrhotic portal hypertension, schistosomiasis, and cirrhosis from various etiologies 3, 4
• Posthepatic causes: Budd-Chiari syndrome (hepatic vein thrombosis), inferior vena cava obstruction 3

Clinical Features

Children with portal hypertension typically present with gastrointestinal bleeding from esophageal varices (100% in surgical series) and splenomegaly with hypersplenism (98% of cases). 1, 2

Primary Manifestations

• Variceal bleeding: Life-threatening hemorrhage from esophageal or gastric varices, representing the most common and dangerous complication 1, 5
• Splenomegaly and hypersplenism: Nearly universal finding leading to thrombocytopenia, anemia, and leukopenia 1, 2
• Ascites: Less common in non-cirrhotic portal hypertension compared to cirrhotic causes due to preserved hepatic synthetic function 1, 6

Cardiopulmonary Complications

• Hepatopulmonary syndrome (HPS): Occurs in 4-29% of children with chronic liver disease, characterized by intrapulmonary vascular dilatations causing hypoxia; importantly can occur without liver dysfunction in conditions like portal vein thrombosis 3
• Portopulmonary hypertension (PPHTN): Rare but devastating complication with mean pulmonary artery pressure >25 mmHg; requires echocardiographic screening and right heart catheterization for diagnosis 3
• Portal biliopathy: Biliary tract abnormalities from venous collaterals compressing bile ducts, presenting with jaundice or cholestasis 4

Investigations

Non-Invasive Screening

• Doppler ultrasound: First-line investigation to assess portal vein patency, direction of flow, presence of collaterals, and splenomegaly 4
• CT or MRI: Used for diagnostic confirmation, extension assessment, and evaluation of vascular anatomy prior to surgical planning 4
• MR cholangiography: Indicated when persistent cholestasis or biliary abnormalities suggest portal biliopathy 4

Endoscopic Evaluation

• Upper endoscopy: Essential for identifying and grading esophageal and gastric varices; should be performed at diagnosis and repeated for surveillance 5, 7
• Variceal classification: Standardized grading systems help predict bleeding risk and guide prophylactic interventions 7

Cardiopulmonary Screening

• Pulse oximetry: Room air measurement in upright position recommended for regular screening of hepatopulmonary syndrome in all children with portosystemic shunting 3
• Transthoracic echocardiography: Best non-invasive screening tool for portopulmonary hypertension; pulmonary artery systolic pressure >40 mmHg warrants further evaluation 3
• Right heart catheterization: Required for definitive diagnosis of portopulmonary hypertension and essential before liver transplantation consideration 3

Diagnostic Confirmation of HPS

Hepatopulmonary syndrome diagnosis requires hypoxia plus one of the following: 3

• Contrast-enhanced transthoracic echocardiography showing delayed appearance of microbubbles in left atrium
• Technetium-labeled macro-aggregated albumin scan with shunt fraction >6%
• Cardiac catheterization demonstrating intrapulmonary vascular dilatations

Thrombophilia Workup

• Prothrombotic screening: Should be performed in all children with portal vein thrombosis to identify underlying risk factors including inherited thrombophilias, myeloproliferative disorders, and autoimmune conditions 1

Management

Acute Variceal Bleeding

Combination therapy with vasoactive drugs plus endoscopic therapy controls bleeding in up to 85-95% of children and should be initiated immediately. 8, 5

• Vasoactive agents: Octreotide or terlipressin started immediately upon presentation and continued for 2-5 days 5
• Endoscopic therapy: Variceal band ligation preferred over sclerotherapy for both efficacy and safety 3, 4, 5
• Antibiotic prophylaxis: Should be administered to prevent bacterial infections and spontaneous bacterial peritonitis 5

Prevention of First Bleeding (Primary Prophylaxis)

Evidence for primary prophylaxis in children is limited, but non-selective beta-blockers should be considered for large varices following the same approach as in cirrhosis. 4, 5

• Non-selective beta-blockers: Propranolol or nadolol reduce splanchnic blood flow and portal pressure; hemodynamic studies show beneficial effects in non-cirrhotic portal hypertension 3, 4
• Endoscopic band ligation: Can be considered for high-risk varices when beta-blockers are contraindicated or not tolerated 4

Prevention of Rebleeding (Secondary Prophylaxis)

Endoscopic variceal band ligation is the optimal therapy for preventing rebleeding and should be combined with non-selective beta-blockers. 4, 5

• Combination therapy: Band ligation plus beta-blockers provides superior protection compared to either modality alone 4
• Surveillance endoscopy: Repeated sessions every 2-4 weeks until variceal eradication, then surveillance every 6-12 months 5, 7
• Rebleeding rate: Approximately 20% at two years with optimal medical and endoscopic therapy 3

Surgical Management

The meso-Rex bypass (mesenterico-portal bypass) is the optimal surgical treatment for children with extrahepatic portal vein obstruction and patent intrahepatic left portal vein, as it restores physiologic portal perfusion. 3, 4, 2

Meso-Rex Bypass Indications

• Patient selection: Children with portal vein thrombosis, accessible intrahepatic left portal vein on imaging, and recurrent bleeding despite endoscopic therapy 3, 2
• Outcomes: High feasibility and long-term patency rates; prevents gastrointestinal bleeding, improves mental status, and normalizes coagulation factors 3, 2
• Definitive treatment: Restores portal perfusion in 18.6% of cases, making it curative rather than palliative 2

Alternative Shunt Procedures

• Distal splenorenal shunt: Indicated when meso-Rex bypass not feasible; performed in 49.3% of surgical cases with good outcomes 1, 2
• Mesocaval shunt: Alternative option used in 28% of cases when other shunts not anatomically possible 2
• Selective portosystemic shunts: Provide excellent long-term results with low mortality and rebleeding rates 6

Surgical Considerations

• Postoperative thromboprophylaxis: Mandatory in all patients to maintain shunt patency 1, 2
• Shunt thrombosis: Occurs in approximately 13% of cases, requiring revision surgery 2
• Mortality: Single-digit mortality rates in experienced centers for non-cirrhotic portal hypertension 1

Transjugular Intrahepatic Portosystemic Shunt (TIPS)

TIPS should be considered for refractory variceal bleeding or when surgical shunts are not feasible, though experience in children remains limited. 3, 5

• Indications: Salvage therapy for uncontrolled bleeding, bridge to transplantation, or when surgical options exhausted 3, 4, 5
• Contraindications: Child-Pugh score >13, severe portopulmonary hypertension (mean PAP >50 mmHg), active infection 3
• Covered stents: Should be used to improve long-term patency 3
• Limitations: Short-term follow-up data only; encephalopathy rates similar to cirrhotic patients despite preserved liver function 3, 5

Management of Specific Complications

Hepatopulmonary Syndrome

Liver transplantation is indicated for children with hepatopulmonary syndrome and portosystemic shunting who are not candidates for shunt closure, as HPS is reversible post-transplant. 3

• Congenital shunt closure: Should be considered as alternative to transplantation when anatomically feasible (e.g., Abernethy malformation) 3
• Supplemental oxygen: Provides symptomatic relief, particularly during physical activity 3
• Prognosis: Median survival <12 months in adults with severe HPS (PaO2 <50 mmHg) without transplantation; pediatric data limited 3

Portopulmonary Hypertension

Children with portopulmonary hypertension should NOT be anticoagulated due to increased risk of severe hemorrhage from varices. 3

• Pulmonary vasodilator therapy: Sildenafil, endothelin receptor antagonists, and prostanoids can stabilize and improve pulmonary pressures, enabling successful liver transplantation 3
• Transplant evaluation: Severe PPHTN (mean PAP >50 mmHg) carries high mortality risk; medical optimization required before transplant consideration 3
• Cardiac catheterization: Essential for accurate hemodynamic assessment before transplantation 3

Portal Biliopathy

Biliary complications should only be treated when symptomatic with jaundice or bile stones. 3

• Endoscopic management: ERCP with stone extraction or stenting for strictures; risk of hemobilia from intrabiliary varices 3
• Surgical shunt: Consider when superior mesenteric or splenic veins patent, as decompression can resolve biliary obstruction 3

Liver Transplantation

Liver transplantation should be considered for children with cardiopulmonary complications of portal hypertension (HPS or PPHTN) or progressive liver failure, even in non-cirrhotic portal hypertension. 3, 8

Transplant Indications

• Cirrhotic portal hypertension: Progressive liver failure, refractory ascites, hepatorenal syndrome, or recurrent variceal bleeding despite optimal therapy 3, 8
• Non-cirrhotic portal hypertension: Cardiopulmonary complications (HPS, PPHTN) that cannot be managed by shunt closure or medical therapy 3
• Budd-Chiari syndrome: Progressive end-stage liver disease not responsive to anticoagulation, TIPS, or hepatic vein interventions 3

Pre-Transplant Evaluation

• Cardiopulmonary assessment: Mandatory echocardiography and right heart catheterization to exclude severe PPHTN (mean PAP >50 mmHg) 3
• HPS screening: Pulse oximetry and contrast echocardiography; presence of HPS not a contraindication but requires careful perioperative management 3
• Thrombophilia workup: Essential in Budd-Chiari syndrome; lifelong anticoagulation typically required post-transplant 3

Outcomes

• HPS resolution: Generally reversible after transplantation with good long-term outcomes 3
• PPHTN resolution: Can resolve post-transplant if adequately treated pre-operatively with pulmonary vasodilators 3

Monitoring and Surveillance

Children with non-cirrhotic portal hypertension require regular screening for portal vein thrombosis (every 6 months) and cardiopulmonary complications. 4

• Endoscopic surveillance: Every 1-2 years for variceal screening in compensated patients; more frequently after variceal eradication 7
• Pulse oximetry screening: Upright room air measurements at each clinic visit to detect early HPS 3
• Echocardiography: Periodic screening for PPHTN, particularly in patients with progressive symptoms 3
• Doppler ultrasound: Regular assessment of shunt patency in post-surgical patients and portal vein status in medical management 4

Prognosis

Children with non-cirrhotic portal hypertension have excellent prognosis with appropriate management, as hepatic encephalopathy and liver failure are rare due to preserved liver function. 4, 6

• Surgical outcomes: Good results achieved in all children with elimination of bleeding risk; mortality rates remain low in experienced centers 1, 2
• Medical management: Endoscopic therapy controls acute bleeding in 95% of cases; rebleeding rates approximately 20% at two years with optimal prophylaxis 4
• Quality of life: Thoughtful application of pharmacologic, endoscopic, and surgical options significantly improves quality of life and decreases mortality 6, 7