Severe sepsis in hematopoietic stem cell transplant recipients*.

OBJECTIVE: Severe sepsis requires timely management and has high mortality if care is delayed. Hematopoietic stem cell transplant recipients are more likely to be immunocompromised and are predisposed to serious infections. Reports of outcomes of severe sepsis in this population are limited to data from single, tertiary care centers, and national outcomes data are missing.
DESIGN: Retrospective analysis of an administrative database.
SETTING: Twenty percent of community hospitals in United States, excluding federal hospitals. SUBJECT: Patients with severe sepsis. INTERVENTION: None.
MEASUREMENTS AND MAIN RESULTS: We used International Classification of Diseases, 9th Edition, Clinical Modification codes indicating the presence of sepsis and organ system failure to identify hospitalizations for severe sepsis between 2000 and 2008. We also used International Classification of Diseases, 9th Edition, Clinical Modification codes to identify hematopoietic stem cell transplant recipients. We compared outcomes of hematopoietic stem cell transplant recipients with severe sepsis during engraftment and subsequent admissions with a non-hematopoietic stem cell transplant cohort and excluded solid-organ transplantation from this cohort. We used mixed effect, multivariate logistic regression modeling with propensity score adjustment to examine factors associated with mortality of severe sepsis in hematopoietic stem cell transplant recipients. A total of 21,898 hematopoietic stem cell transplant recipients with severe sepsis were identified. The frequency of severe sepsis in hematopoietic stem cell transplant recipients was five times higher when compared with the non-hematopoietic stem cell transplant cohort. The unadjusted mortality was 32.9% in non-hematopoietic stem cell transplant cohort, which was similar to autologous hematopoietic stem cell transplant recipients (30.1%) and those who did not develop graft-versus-host disease (35%). Mortality was significantly higher in allogeneic transplants (55.1%, p < 0.001) and in those who developed graft-versus-host disease (47.9%, p < 0.001). After adjustment, during engraftment admission, the odds of in-hospital mortality in allogeneic hematopoietic stem cell transplant (odds ratio, 3.81; 95% CI, 2.39-6.07) and autologous hematopoietic stem cell transplant (odds ratio, 1.28; 95% CI, 1.06-1.53) recipients was significantly higher than non-hematopoietic stem cell transplant patients. Similarly, in subsequent admissions, hematopoietic stem cell transplant recipients with graft-versus-host disease (odds ratio, 2.14; 95% CI, 1.88-2.45) and without graft-versus-host disease (odds ratio, 1.35; 95% CI, 1.19-1.54) had significantly higher odds of mortality than non-hematopoietic stem cell transplant patients. Among patients with hematopoietic stem cell transplant, persons with autologous hematopoietic stem cell transplant and those without graft-versus-host disease fared better as compared with their allogeneic and graft-versus-host disease counterparts.
CONCLUSIONS: Hematopoietic stem cell transplant recipients are more likely to develop severe sepsis and die following a severe sepsis episode than nontransplant patients. Autologous hematopoietic stem cell transplant recipients and those who do not develop graft-versus-host disease have significantly better outcomes than allogeneic and graft-versus-host disease patients.