Type of Hematopoietic Stem Cell Transplant Source of Stem Cells Risk of Early Infection: Neutrophil Depletion Risk of Late Infection: Impaired T and B Cell Function Risk of Ongoing Infection: GVHD and Iatrogenic Immunosuppression Graft versus Tumor Effect
Autologous Recipient (self) High risk; neutrophil recovery sometimes prolonged 1 year Minimal to no risk of GVHD and late-onset severe infection None (-)
Syngeneic (genetic twin) Identical twin Low risk; 1-2 weeks for recovery 1 year Minimal risk of GVHD and late-onset severe infection +/-
Allogeneic related Sibling Low risk; 1-2 weeks for recovery 1 year Minimal to moderate risk of GVHD and late-onset severe infection ++
Allogeneic related Child/parent(haploidentical) Intermediate risk; 2-3 weeks for neutrophil recovery 1-2 years Moderate risk of GVHD and late-onset severe infection ++++
Allogeneic unrelated adult Unrelated donor Intermediate risk; 2-3 weeks for neutrophil recovery 1-2 years High risk of GVHD and late-onset severe infection ++++
Allogeneic unrelated cord blood Unrelated cord blood units (x2) Intermediate to high risk; neutrophil recovery sometimes prolonged Prolonged Minimal to moderate risk of GVHD and late-onset severe infection ++++
Allogeneic mini (nonmyeloablative) Donor (transiently coexisting with recipient cells) Low risk; neutrophil counts close to normal 1-2+ years Variable risk of GVHD and late-onset severe infection ++++ (but develops slowly)
Table 1: Infection risk associated with type of transplant.