To study the effect of early lymphocyte recovery post-allogeneic hematopoietic stem cell transplantation (HSCT) on outcome in pediatric ALL, we reviewed 136 consecutive pediatric patients with ALL who received allogeneic HSCT between 1994 and 2005 at the Hospital for Sick Children, Toronto, Canada. Patients with an absolute lymphocyte count (ALC) o0.3 Â 10 9 per liter at day 21 (n ¼ 104) had more than five times risk of relapse compared to those with ALC 40.3 Â 10 9 per liter (n ¼ 32) (hazard ratio (HR) 5.3; P ¼ 0.002) and had inferior 3-year event-free survival, (EFS), 0.42 (95% confidence interval (CI) 0.32, 0.51) compared to 0.66 (95% CI 0.48, 0.82; P ¼ 0.02). Similarly, patients with an ALC o0.3 Â 10 9 per liter (n ¼ 48) at day 30 were more than twice as likely to relapse compared to those with an ALC 40.3 Â 10 9 per liter (n ¼ 88) (HR 2.2; P ¼ 0.01) and had an inferior 3-year EFS, 0.30 (95% CI 0.18, 0.45) compared to 0.57 (95% CI 0.46, 0.68; P ¼ 0.0001). Interestingly, increasing ALC at days 21 and 30 was not associated with increased incidence of acute or chronic GVHD or transplant-related mortality (TRM). Early lymphocyte recovery post-HSCT is associated with a significant GVL without increase in GVHD.

Glanzmann thrombasthenia (GT) is a rare autosomal recessive bleeding disorder characterized by normal platelet count, but lack of platelet aggregation. The molecular basis is linked to quantitative and/or qualitative abnormalities of the membrane glycoprotein IIb/IIIa complexes. Usually it is associated with mild bleeding but may lead to severe and potentially fatal hemorrhages. Allogeneic hematopoietic stem cell transplantation (HSCT) is the only curative treatment. However, because of the risks associated with HSCT, it is generally not recommended unless there are life threatening hemorrhages, or the patient has developed refractoriness to platelet transfusion due to antibody formation. Herein, we report an 11-year-old female from United Arab Emirates (UAE) with severe GT and anti platelet alloimmunization successfully treated with HSCT from her HLA-identical sibling.

We reviewed 70 consecutive children with AML who received hematopoietic stem cell transplantation (HSCT) in our institution between 1994 and 2005. Forty-seven children were transplanted in CR1 and 23 were transplanted in CR2. BU/CY was the most common pretransplant conditioning regimen for CR1 patients and a TBI-based conditioning regimen was the most common regimen for CR2 patients. Most patients transplanted in CR1 (81%) received related donor HSCT, whereas most of the CR2 patients (74%) received unrelated donor HSCT. Expectedly, there was a significant increase in acute GVHD incidence in CR2 patients (40 vs 25% for grades I-II and 30 vs 10% for grades III-IV; P ¼ 0.02) and a significant increase in transplant-related mortality (38 vs 11%; P ¼ 0.01). Although the difference between 3-year EFS for CR1 and CR2 was not statistically significant, there was a significantly superior 3-year overall survival for CR1 patients (74 vs 51%; P ¼ 0.05). Children with relapsed AML who achieve and maintain remission until HSCT, have a reasonable survival, but the outcome of children receiving HSCT in CR1 remains superior.