Abstract
BACKGROUND:
Thrombopoietin (TPO), the major physiological regulator of platelet formation, binds to and activates TPO receptor on megakaryocytes, thereby promoting platelet production. Recombinant human thrombopoietin (rhTPO) is a novel therapeutic option for patients with immune thrombocytopenia (ITP) in China. However, the safety and efficacy of rhTPO for ITP patients in pregnancy is unclear. We report two ITP patients in pregnancy successfully treated with rhTPO.
METHODS:
Patient one, who was diagnosed as ITP according to the ASH guidelines two years ago, was a 28-year-old G2P1 pregnant woman, with a platelet count of 10×109/L and gingival bleeding. Before rhTPO therapy her TPO level was 231pg/mL. Patient two, who was diagnosed as ITP one year ago, was a 23-year-old primigravid woman with gross hematuria at 22-week gestation. Her platelet count was 19×109/L and the level of TPO in her plasma was 107pg/mL before rhTPO admission. Both patients failed to respond to prednisone (1mg/kg, 14d) and intravenous immunoglobulin (IVIG, 0.4g/kg, 5d). Due to persistent hemorrhage, they received rhTPO at a daily dose of 300U/kg daily (3SBIO Pharmaceutical Co., LTD, Shenyang, China). When their platelet counts rose above 50×109/L, maintenance therapy (rhTPO 300U/kg, every other day) started. This treatment protocol was approved by the Medical Ethical Committee of Qilu Hospital, Shandong University.
RESULTS:
The platelet count of patient one rose to 165×109/L after 10 days of rhTPO therapy. Then rhTPO maintenance therapy was applied. On the 39th week, she vaginally delivered a female infant with normal platelet count. The TPO level of the newborn was 127pg/mL. In the second case, after seven days of rhTPO therapy, her platelet count rose to 58×109/L, then we started rhTPO maintenance therapy. On the 40th week, she delivered a female infant without any signs of neonatal ITP. The level of TPO in the infant's plasma was 174pg/mL. Maintenance therapy continued after delivery with a dose of 300U/kg per week. The platelet counts of patients during treatment were illustrated in Figure 1. At a 1-month follow-up visit, no adverse events were observed in both infants.
CONCLUSION:
RhTPO may be an effective and fast-onset treatment for ITP in pregnancy. Future studies are necessary to investigate the safety and efficacy of rhTPO in this clinical setting.
No relevant conflicts of interest to declare.
