Treatment of Sinusoidal Obstruction Syndrome With Defibrotide in Pediatric Cancer Patients Following Nontransplant-associated Chemotherapy: A Case Report and Review of the Literature

Severe hepatic sinusoidal obstruction syndrome in a patient with Wilms tumor and hereditary spherocytosis

A 7-year-old girl with a history of splenectomy for hereditary spherocytosis (HS) was diagnosed with renal hematoma after a blunt abdominal trauma while receiving aspirin. Multiple erythrocyte transfusions and transarterial embolization were performed without success. Eventual nephrectomy revealed severely necrotic and perforated Stage III Wilms tumor (WT). Radiochemotherapy was administered, but by the eighth week, she developed severe hepatic sinusoidal obstruction syndrome (HSOS). Her ferritin level at the time was 3406 ng/ml. Defibrotide and aggressive supportive measures provided full recovery. The patient was given deferasirox for iron chelation therapy and finished her treatment without incident. To our knowledge, just one patient with HS and WT has been described in the literature. The role of iron excess in HSOS pathogenesis in non-transplant patients has not been addressed before either. Transfusional hyperferritinemia, in addition to chemotherapeutics and radiation, may have contributed to the development of severe HSOS in our patient.

Sinusoidal Obstruction Syndrome of the Liver Associated With 6-Mercaptopurine During Maintenance in a Child With T-cell Acute Lymphoblastic Leukemia

Sinusoidal obstruction syndrome (SOS) of the liver is a complication of chemotherapy most often encountered with hematopoietic stem cell transplant due to high-dose conditioning regimens, but it can also occur with regimens outside of the transplant setting. Mild-to-moderate SOS is a well-described 6-thioguanine toxicity; however, it has rarely been reported as secondary to 6-mercaptopurine, a related thiopurine. This report details a case of a 10-year-old male with T-cell acute lymphoblastic leukemia who developed severe SOS during maintenance therapy with 6-mercaptopurine, and a review of the related literature.