Portosinusoidal vascular disorder

Portosinusoidal vascular disorder (PSVD) is a rare noncirrhotic portal hypertension syndrome characterized by lesions involving the portal venules and/or sinusoids. PSVD unifies several older diagnoses and histological patterns (e.g., idiopathic noncirrhotic portal hypertension, hepatoportal sclerosis, incomplete septal cirrhosis) under one umbrella diagnosis. Patients typically have portal hypertension with preserved hepatic function and biopsies that show vascular or architectural remodeling without cirrhosis. Causes include immunological disorders, infections, drugs (e.g., oxaliplatin, azathioprine), and genetic factors. Diagnosis requires a liver biopsy to exclude cirrhosis and identify histological lesions. Patients are often asymptomatic but may present with clinical features of portal hypertension (e.g., variceal bleeding, splenomegaly). Management focuses on treating underlying conditions and managing portal hypertension.

• PSVD is a rare noncirrhotic portal hypertension syndrome characterized by lesions involving the portal venules and/or sinusoids.
• PSVD encompasses the following former diagnoses:
  • Idiopathic noncirrhotic portal hypertension
  • Nodular regenerative hyperplasia
  • Obliterative portal venopathy
  • Hepatoportal sclerosis
  • Incomplete septal cirrhosis
  • Noncirrhotic portal fibrosis

• Immunological disorders ^[1]
  • Common variable immune deficiency
  • Systemic lupus erythematosus
  • Felty syndrome
  • Inflammatory bowel disease
• Infections ^[1]
  • HIV infection
  • Recurrent abdominal infections
• Hematological disorders ^[1]
  • Myeloproliferative neoplasms
  • Idiopathic thrombocytopenic purpura
  • Aplastic anemia
  • Hodgkin lymphoma
  • Multiple myeloma
  • Castleman disease
  • Chronic lymphoid leukemia
• Prothrombotic disorders ^[1]
  • Antithrombin deficiency
  • Protein C deficiency
  • Protein S deficiency
  • Antiphospholipid syndrome
  • Factor V Leiden mutation
  • Paroxysmal hemaglobinuria
• Drugs and toxins ^[1][2]
  • Chemotherapy
    • Oxaliplatin
    • 5-fluorouracil
  • Immunosuppressants
    • Azathioprine
    • 6-thioguanine
  • Antiretrovirals
    • Didanosine
    • Stavudine
  • Toxins
    • Arsenic
    • Vinyl chloride ^[2]
• Genetic factors ^[1]
  • Turner syndrome
  • Adams-Oliver syndrome
  • Mutations in, e.g., DGUOK, KCNN3, GIMAP5, FOPV, FCHSD1, HLA-DR 3, TRMT5, HRG

Patients may be asymptomatic or present with clinical features of portal hypertension. ^[1]

General principles ^[1][3]

• Suspect PSVD in patients with signs of portal hypertension with preserved liver function and/or unexplained liver enzyme abnormalities.
• Diagnostic criteria
  • Biopsy-confirmed exclusion of cirrhosis with at least one of the following:
    • ≥ 1 specific signs of portal hypertension (e.g., gastric varices and/or esophageal varices, portal hypertensive bleeding, portosystemic collaterals on imaging)
    • ≥ 1 specific histological lesion (i.e., obliterative portal venopathy, nodular regenerative hyperplasia)
    • ≥ 1 suggestive sign of portal hypertension (e.g., thrombocytopenia, splenomegaly, ascites) with ≥ 1 suggestive histological lesion
• Perform a targeted evaluation for possible causes based on clinical suspicion.

PSVD is diagnosed when cirrhosis and other chronic advanced liver diseases are excluded and the patient has either a specific clinical or histological feature of PSVD, or a combination of compatible clinical and histological findings.

Laboratory studies ^[1][3]

• LFTs
  • Normal albumin and bilirubin
  • Mild to moderate elevation of AST, ALT, ALP, GGT may be present.
• CBC: thrombocytopenia

Cross-sectional imaging ^[1][3]

• Liver morphology
  • Smooth liver surface with normal-size or enlarged segment IV (unlike cirrhosis)
  • Caudate lobe hypertrophy and right liver atrophy or hypotrophy may be present.
• Portal hypertension signs: splenomegaly, portosystemic collaterals
• Vascular abnormalities: portal vein abnormalities (thickening, reduced caliber)
• Focal lesions: Benign hyperplastic nodules are more common in PSVD than in cirrhosis.

Additional studies

• Elastography ^[1][3]
  • Liver stiffness typically normal or mildly elevated (< 10 kPa) despite signs of portal hypertension
  • Spleen stiffness: High spleen-to-liver stiffness ratio helps distinguish PSVD from cirrhosis.
• Hepatic venous pressure gradient: normal or mildly elevated (< 10 mm Hg) despite clinical portal hypertension due to the presinusoidal component of resistance

Liver biopsy ^[1]

• Specific findings, i.e.:
  • Obliterative portal venopathy (portal vein sclerosis)
  • Nodular regenerative hyperplasia
• Suggestive findings, e.g.:
  • Incomplete septal fibrosis
  • Mild sinusoidal dilatation
  • Perisinusoidal fibrosis

• Cirrhosis
• Budd-Chiari syndrome
• Extrahepatic portal vein obstruction
• Sinusoidal obstruction syndrome
• Congenital hepatic fibrosis
• Sarcoidosis
• Schistosomiasis
• Liver infiltration by tumor cells
• See also: "Causes of portal hypertension."

The differential diagnoses listed here are not exhaustive.

• Manage underlying diseases.
• Stop causative drugs if feasible.
• Provide management of portal hypertension, e.g.:
  • Pharmacological treatment with nonselective beta blockers
  • Portosystemic shunts (e.g., TIPS) for refractory disease
  • Management of complications of portal hypertension (e.g., treatment of ascites, treatment of hepatic encephalopathy, treatment of esophageal varices)
• Liver transplantation for patients with refractory complications of portal hypertension or progressive liver failure that does not respond to other therapies

See "Complications of portal hypertension."

We list the most important complications. The selection is not exhaustive.