Veno-occlusive disease
Veno-occlusive disease is a post bone marrow transplant complication.
A combination of pre-transplant risk factors, and transplant related conditions are believed to trigger primary hepatic sinusoidal injury, although a definitive underlying cause is unknown. This can lead to hepatocytic and panvasculitic disease, which is followed by multiorgan failure.
Histology –
- Early – widening of the subendothelial zone, red cell extravasation, fibrin deposition, and expression of factor VIII/von Willebrand factor within venule walls, followed by necrosis of the perivenular hepatocytes
- Late – deposits of extracellular matrix, an increased number of stellate cells, and subsequent sinusoidal fibrosis.
- Overall this leads to complete venular obliteration and replacement of normal liver tissue with fibrous tissue.
Risk factors:
- Preexisting liver disease
- Second myeloablative hematopoietic stem cell transplantation (HSCT)
- History of treatment with gemtuzumab ozogamicin
- Allogeneic HSCT for leukemia beyond the second relapse
- Conditioning with busulfan, melphalan, or both
- Osteopetrosis
- Macrophage-activating syndromes (eg, hemophagocytic lymphohistiocytosis, Griscelli syndrome)
Clinical symptoms:
- weight gain
- an increase in abdominal circumference
- hepatomegaly
- right upper quadrant pain
- ascites
- elevated total and direct bilirubin levels.
- transfusion-refractory thrombocyotopenia
VOD usually occurs within 20 days post transplant
Work up:
- FBC
- Chimerism
- Bilirubin
- LFTS
- Coagulation, incl D-dimer
- CRP
- USS, DOPPLER. – diagnostic finding is reversal of flow in the portal and hepatic veins
Possible treatments:
Defibrotide – a single-stranded polydeoxyribonucleotide derived from porcine tissue that possesses antithrombotic, thrombolytic, anti-inflammatory, and anti-ischemic properties