Incidence, risk factors, and outcome of bloodstream infections during the pre‐engraftment phase in 521 allogeneic hematopoietic stem cell transplantations

Abstract

Background Bloodstream infection (BSI) after allogeneic hematopoietic stem cell transplantation (HSCT) is a well‐known complication during the pre‐engraftment phase. Knowledge of trends in etiology and antibiotic susceptibility of BSI is important as the time to effective antibiotic treatment is closely associated with survival in bacteremic patients with septic shock. Methods BSI during the pre‐engraftment phase was studied retrospectively in 521 patients undergoing HSCT at our center in 2001–2008. Incidence, risk factors, outcome, and microbiology findings were investigated and compared with BSI in a cohort transplanted during 1975–1996. Results The incidence of at least 1 episode of BSI was 21%, the total attributable mortality of BSI was 3.3%, and crude mortality at day 120 after transplantation was 21%. The rate of gram‐positive and gram‐negative BSI was 80% and 13%, respectively. Gram‐negative BSI was more frequent both in 2001–2004 and in 2005–2008 compared with 1986–1996 (P = 0.023 for 2001–2004, P = 0.001 for 2005–2008), with fluoroquinolone‐resistant Escherichia coli as the predominant finding. BSI with viridans streptococci and E. coli occurred significantly earlier after HSCT than BSI with Enterococcus species, with median time of 4, 8, and 11 days, respectively (P < 0.01 both for viridians streptococci vs. Enterococcus species, and E. coli vs. Enterococcus species). Risk factors for BSI in multivariate analysis were transplantation from unrelated donor and cord blood as stem cell source, whereas peripheral blood as stem cell source was protective. Conclusions Despite low attributable mortality of BSI, crude mortality at day 120 after transplantation was 21%, indicating an association between BSI and other risk factors for death. The risk of gram‐negative BSI increased over time in parallel with an increased rate of quinolone resistance. However, the incidence and attributable mortality of gram‐negative BSI remained low. Thus, prophylaxis with ciprofloxacin is still deemed appropriate, but continued assessments of the risk and benefits of fluoroquinolone prophylaxis must be performed.

Bloodstream infections in neutropenic cancer patients: A practical update

“…90,91 In fact, in case of allogeneic HSCT, some types of donors, such as unrelated and cord blood, were associated with higher rate of BSI, probably because of longer pre-engraftment neutropenia, compared to peripheral blood as a stem source. 92 Male sex and advanced acute myeloid leukemia were found to increase the risk of BSIs in peripheral blood stem-cell transplantation in a large German study, while another cohort confirmed higher risk of BSI in case of acute leukemia and prolonged hospital stay, but found the opposite effect of the gender (higher BSI risk in females). 78,93 The presence of relapsed malignancy was also associated with an increased risk of bacteremia in a large study of pediatric cancer patients.…”

Bacterial bloodstream infections in the allogeneic hematopoietic cell transplant patient: new considerations for a persistent nemesis

“…27 As such, patients receiving RIC conditioning regimens typically have lower rates of BSI, likely due to decreased mucositis and shorter durations of neutropenia. 27,28 However, pediatric patients undergoing RIC transplant for non-malignant disease have been noted to have an increased BSI risk, 5 which may reflect the added risk for BSI associated with the underlying diagnosis itself (for example, primary immunodeficiency).…”

Stem cell transplantation during cancer

“…Neutrophils and monocytes are the first cells to recover, closely followed by the NK cells. Consequently, during the first month after HSCT the patient is very susceptible to infections (33). …”