Extensive chronic GVHD is associated with donor blood CD34+ cell count after G-CSF mobilization in non-myeloablative allogeneic PBSC transplantation.

The correlation between the incidence of GVHD and the number of infused CD34(+) cells remains controversial for PBSC transplantation after a reduced-intensity-conditioning (RIC) regimen. We evaluated 99 patients transplanted with an HLA-identical sibling after the same RIC (2-Gy-TBI/fludarabine). Donor and recipient characteristics, donor's blood G-CSF-mobilized CD34(+) cell count, and number of infused CD34(+) and CD3(+) cells were analyzed as risk factors for acute and chronic GVHD There was a trend for an increased incidence of extensive chronic GVHD in the quartile of patients receiving more than 10 × 10(6) CD34(+) cells/kg (P = 0.05). Interestingly, the number of donor's blood CD34(+) cells at day 5 of G-CSF mobilization was closely associated with the incidence of extensive chronic GVHD, that is, 48% (95% CI: 28-68) at 24-months in the quartile of patients whose donors had the highest CD34(+) cell counts versus 24.3% (95% CI: 14-34) in the other patients (P = 0.007). In multivariate analysis, the only factor correlating with extensive chronic GVHD (cGVHD) was the donor's blood CD34(+) cell count after G-CSF (HR 2.49; 95% CI: 1.16-5.35, P = 0.019). This study shows that the incidence of cGVHD is more strongly associated with the donor's ability to mobilize CD34(+) cells than with the number of infused CD34(+) cells.

Double cord blood transplantation in patients with high risk bone marrow failure syndromes.

Patients with bone marrow failure syndromes (BMFS) who reject a first allogeneic transplant or fail immunosuppressive therapy (IST) have an especially grim prognosis. We report 14 patients (eight adults, six children) transplanted with double cord blood transplantation (dUCBT) for BMFS. Neutrophil recovery was observed in eight patients, with full donor chimerism of one unit, and acute GVHD in 10. With a median follow-up of 23 months, the estimated 2 years overall survival was 80 +/- 17% and 33 +/- 16% for patients with acquired and inherited BMFS, respectively. Transplantation of two partially HLA-matched UCB thus enables salvage treatment of high-risk patients with BMFS.

Microbial contamination of BM products before and after processing: a report of incidence and immediate adverse events in 257 grafts.

BACKGROUND: The incidence and potential clinical consequences of bacterial contamination of autologous and allogeneic BM products remains open to question. We report our experience of bacterial contamination of BM grafts and adverse events that occurred after transplantation. METHODS: From January 2003 to February 2006, 257 BM harvests were processed and infused at our institution. Analysis of microbial contamination incidence before and after processing, sensitivity spectra of isolated bacteria and adverse events after graft infusion were analyzed. RESULTS: Nineteen of 257 BM (7.4%) were contaminated. Coagulase-negative Staphylococcus (n=9) and Propionibacterium acnes (n=6) were the most frequently isolated microorganisms. Two of nine coagulase-negative staphylococci were found to be resistant to erythromycin and two of six P. acnes to fosfomycin and gentamycin. The frequency and severity of immediate adverse events reported in patients receiving a contaminated graft were similar to those observed in patients receiving a non-contaminated product. No major adverse sequelae occurred after infusion of contaminated grafts. Finally, none of the patients transplanted with a contaminated graft developed bacteriemia that could have been related to the isolated microorganism. DISCUSSION: Microbial contamination of BM progenitor cell grafts does not induce severe clinical complications or infectious diseases after infusion. The vast majority of isolated pathogens were skin contaminants.