Young Female Donors Do Not Increase the Risk of Graft-versus-Host Disease or Impact Overall Outcomes in Pediatric HLA-Matched Sibling Hematopoietic Stem Cell Transplantation.

Young Female Donors Do Not Increase the Risk of Graft-versus-Host Disease or Impact Overall Outcomes in Pediatric HLA-Matched Sibling Hematopoietic Stem Cell Transplantation.
This is a retrospective cohort study, in 244 pediatric patients, to address the hypothesis that the presence of T and B cells sensitized by exposures during pregnancy are a contributing factor to differences in outcomes between sex-matched and sex-mismatched transplants. Theoretically, there should be no such difference when a non-exposed (non-alloimmunized) female donor is used. In the study, they assume that young (12 years) female donors are a sexually naïve population and therefore the presence of alloimmunization including to H-Y antigens should be minimal.
Data from 244 pediatrics patients were analyzed. The outcome was the development of acute grade II to IV GVHD and Chronic GVHD. Survival analysis was assessed at 100 days, 1 year and 5 years. Age was dichotomized to improve the interpretability of the results.
Donor age >12 yrs represents 50% of the population in the study. Univariate analysis revealed older patient age, older donor age, conditioning with CY-TBI and earlier year of transplant as significant predictor of aGVHD. Of these, all but donor age showed significance in multivariate analysis.
The effect of female donor sex on cGVHD noted in the model adjusted for patient age, HLA match, and stem cell source lost significance if the donor was 12 years old, but increased in magnitude and was significant if the donor was ≥12 years old (OR, 13.6; 95% CI, 2.8 to 39.6). Patient age was not a significant risk factor in multivariate analyses.
Population sample inclusion criteria did not consider important factors as:
donor history of blood transfusions and the wide age range of participants. Age was used as a surrogate for sexual-naivety and therefore it does not directly answer the question.
The study concluded that when selecting among sibling donors for a pediatric patient, priority should be given to donors 12 years of age or younger and that selection can be done independently of donor gender and sex match. Other explanations for the results of this study cannot be excluded and many limitations on patient enrolment criteria, age, and confounding factors could have impacted the results.