[Low dose heparin for the prevention of hepatic veno-occlusive disease after allogeneic hematopoietic stem cell transplantation].

OBJECTIVE

To explore the safety and efficacy of low dose heparin for the prevention of hepatic veno-occlusive disease (VOD) after allogeneic hematopoietic stem cell transplantation (allo-HSCT) conditioned with busulfan and cyclophosphamide (BU-CY2) and the ideal time frame of the heparin administration.

METHODS

From April 1997 to December 2005, 134 patients (75 male, 59 female; median age 25 years old) were transplanted in our bone marrow transplantation unit. All patients were conditioned with BU-CY2 or busulfan-based regimen and scheduled to receive a continuous injection of heparin at a dose of 100 IUxkg-1xd-1. The patients were divided into different groups: 87 patients received related donor transplantation and 47 patients unrelated donor transplantation; 40 patients had abnormal liver function prior to transplantation and the remaining 94 patients normal liver function; 68 patients received heparin from day -7 to day +21 post HSCT and the other 66 patients from day -7 to day +14.

RESULTS

All 134 patients had sustained engraftment. The median time for neutrophils to reach 0.5 x 10(9)/L and for platelets to reach 20x10(9)/L were 12 days (range 9-28) and 20 days (range 6-65), respectively. The disease-free survival at day +100 for leukemia patients was 82.2% (97/118). None of 134 patients developed VOD (0%), including 10 patients with class 3 thalassemia major. The incidence and severity of clinical bleeding events in 15 patients monitored with prothrombin time and activated partial thromboplastin time is comparable with those not monitored.

CONCLUSIONS

It is suggested that low dose heparin alone is effective and safe for the prophylaxis of VOD following allo-HSCT conditioned with BU-CY regimen. Shortening the duration of administering heparin from -7 d to +21 d to -7 d to +14 d does not affect the effectiveness of low dose heparin to prevent VOD.