Autologous CD34(+) enriched peripheral blood progenitor cell (PBPC) transplantation is associated with higher morbidity in patients with lymphoma when compared to unmanipulated PBPC transplantation

High-dose chemotherapy followed by CD34(+) enriched peripheral blood progen itor cell (PBPC) transplantation is used for the treatment of primary refra ctory or relapsed Hodgkin's and non-Hodgkin's lymphomas, The CD34(+) enrich ment procedure, while reducing tumor burden, may compromise immunological r econstitution in the transplanted patient and result in increased rates of post-transplant infection. We compared infectious complications in patients with lymphoma who were treated with high-dose chemotherapy and supported e ither with CD34(+) enriched PBPC (n = 19) or unmanipulated PBPCs (n = 24). Analysis was limited to patients discharged from initial hospitalization fo r transplantation with a minimum of 1 year followup and free of lymphoma re currence. We found a statistically significant increase in the number of pa tients with one or more infectious events in the CD34(+) transplant group ( 14/19) compared with the unmanipulated PBPC group (9/24, P < 0.01). Greater numbers of patients with two or more infectious events were observed in th e CD34(+) group (7/19 vs 2/24, P < 0.03) and an increased incidence of bact erial infections was observed in the CD34(+) group (10/19 vs 5/24, P < 0,05 ). Two deaths due to infectious complications were observed in the CD34(+) group. There was no significant difference in blood lymphocyte or monocyte recovery between the groups. These data demonstrate a significant increase in the long-term incidence of infectious events in lymphoma patients transp lanted with autologous CD34(+) enriched PBPCs compared to unmanipulated PBP Cs. Thus, patients who undergo CD34(+) enriched PBPC transplantation should be followed closely for infectious complications and prolonged infectious prophylaxis should be considered.