Allogeneic stem cell transplantation from donors other than HLA-matched siblings results in a high risk of posttransplant infections because of the risk of graft-versushost disease (GVHD) with an unmanipulated graft, or delayed immune reconstitution following T cell-depletion (TCD). We compared infectious outcomes in the first yr post-transplant (tx) in 28 consecutive recipients of stringently TCD blood hematopoeitic progenitor cell (HPC) grafts from haploidentical family donors (HD), and 28 consecutive recipients of unmanipulated grafts from matched or 1 Ag mismatched unrelated donors (URD). Included are pts (excluding CML-CPl) transplanted at our center between 6198 and 12/01 after myeloablative conditioning. HD pts received pre-tx ATG, and no scheduled post-tx immunosuppression. URD pts received tacrolimus and methotrexate for GVHD prophylaxis. Median CD3-t cell dose/kg was 3.6 logs lower in the HD vs URD grafts (p
loo), and CMV disease were similar in the two groups.
EBV-associated PTLD was unique to HD pts (n=3),
and drug-resistant HSV disease was also more common
after HD tx. Infection related deaths (censored at 1 yr)
in HD pts included bacterial sepsis (3),Aspergillosis (3)
parainfluenza pneumonia (2) PCP (1) other pneumonia
(l), amebic encephalitis (1) toxoplasmosis (1) EBVPTLD
(l), and acalculous cholecystitis (1). Infectious
deaths in URD pts resulted from IF1 (3) bacterial sepsis
(2), CMV pneumonia (1) aspiration pneumonia (1) and
acalculous cholecystitis (1).
Infections are the most common cause of death in these
pts. The trend toward higher risk of infectious death
following TCD HD vs unmanipulated URD transplants
was not statistically significant, although the spectrum of
infections was different. Strategies aimed at enhancing
immune reconstitution without stimulating GVHD are
needed to reduce the risks of infection and relapse after
stringently TCD alternative donor transplantation.
Full conference title:
12th International Symposium on Infections in the Immunocompromised Host
- ISIIH 12th