Engraftment and Chimerism
Neutrophil engraftment with a sustained absolute neutrophil count of
greater than 500 (109/L) occurred in 5 patients at a
median of 15 (range 8-21) days post-transplantation. Platelet
engraftment with a sustained platelet count greater than 20,000
(109/L) without transfusion occurred at a median of 12
(range 9-16) days post-transplantation. Patient 3 started engraftment
with an absolute neutrophil count 400 x109/L on day
+11 with 100% chimerism, however she died before engraftment due to
sepsis and multiorgan failure. Patients 5 and 6 engrafted with 90% of
donor cells but 3 months post-transplantation started to decrease
chimerism; despite early discontinuation of immunosuppression and
repeated donor lymphocyte infusions they developed secondary engraftment
failure one-year post-transplantation.