Sinusoidal obstruction syndrome (SOS)
(Bone Marrow Transplant 2020:55:485)
- Occlusion hepatic venules & sinusoids (formerly veno-occlusive disease) 2/2 toxic insult
Etiologies:
- post HSCT (15%),
- chemo (cyclophosphamide, cytarabine),
- XRT, bush tea
Clinical manifestations:
- painful hepatomegaly,
- RUQ pain,
- ascites,
- weight gain,
- ↑ bilirubin
Dx:
- U/S w/ reversal of portal flow
- dx made clinically
- early weight gain
- ↓ plt refractory to transfusion
- ↑ bili, hx of recent toxins
- if necessary, liver bx or HVPG (>10 mmHg)
Rx:
- supportive,
- diuretics;
- if severe → early defibrotide ↑ survival,
- but side effects & expensive
Ppx
- defibrotide
- ursodeoxycholic acid for high-risk HSCT pop
- ? low-dose heparin
incidence ~10%, mortality ~30%
- Previously known as veno-occlusive disease (VOD) (BBMT 2016;22:400).
- Mechanism: direct cytotoxic injury to hepatic venules → in situ thrombosis.
- Symptoms: tender hepatomegaly, ascites, jaundice, fluid retention with severe disease → liver failure, encephalopathy, hepatorenal syndrome
- Diagnosis: ↑ ALT/AST, ↑ bilirubin; ↑ PT with severe disease; Doppler U/S may show reversal of portal vein flow; ↑ hepatic wedge pressure; abnl liver bx
- Treatment: supportive; prophylaxis with ursodiol; treat w/ defibrotide (Blood 2016;127:1656)