1673. Incidence of Bacteremia and Associated Mortality after Allogeneic Stem Cell Transplantation during Two Different Prophylactic Strategies: A 12-Year Experience at Memorial Sloan-Kettering Cancer Center (MSKCC)
Session: Poster Abstract Session: Pre-emptive Therapy in Transplantation and Immunocompromised Hosts
Saturday, October 5, 2013
Room: The Moscone Center: Poster Hall C
Posters
  • ID week poster final.pdf (544.5 kB)
  • Background: Information regarding the efficacy of antibiotic prophylaxis during the initial phase of allogeneic stem cell transplantation (HSCT) is limited. This study aimed to analyze the effect of antibiotic prophylaxis on the incidence of bacteremia and infection-related mortality.

    Methods: This was an observational cohort study of 830 consecutive adult HSCT receiving myeloablative or reduced intensity conditioning regimens from 2000-2011 at MSKCC. Bacteremias occurring from day -7 to +100 post HSCT were identified. Since November 2005, all patients were given vancomycin prophylaxis from day -2 through day +7. Fluoroquinolone (FQ) prophylaxis was given to cord blood recipients starting in November 2006. Overall incidence of bacteremia and attributable mortality in 2000-2005 (period A) and 2006-2011 (period B) were estimated with Kaplan-Meier methods. Risk factors for preengraftment bacteremia were identified using Cox proportional hazard models.

    Results: During the study period, 265 (24%) patients had 310 bacteremic episodes with 334 pathogens isolated. Vancomycin-resistant Enterococcus was the most commonly isolated gram-positive bacteria (39%), followed by viridans group streptococci (15%), while Escherichia coli was the most common gram negative rod (26%). The rates of bacteremia per 100 HSCT days decreased from 4.45 in period A to 2.9 in period B (P=0.01). Infection-related mortality was significantly higher in period A (7% in period A vs 2% in period B, P=0.002). Mortality within 100 days of HSCT was directly attributable to viridans streptococcal bacteremia (VSB) in 3 of 15 patients in period A. VSB incidence was dramatically reduced (period A, 7% vs period B, 0.5%) with no VSB attributable mortality in period B. Multivariate analyses showed that vancomycin prophylaxis decreased preengraftment bacteremia (hazard ratio [HR], 0.51; 95% confidence interval [CI], 0.34 to 0.75). While FQ prophylaxis lowered preengraftment bacteremia by 27%, the difference was not statistically significant (HR, 0.73; 95% CI, 0.51 to 1.04).

    Conclusion: Vancomycin prophylaxis was associated with decreased incidences of preengraftment bacteremia, mainly due to the dramatic decrease of VSB. Infection-related mortality was also reduced during the prophylactic period.

    Ubonvan Jongwutiwes, MD1, Kun Xiao, MD MPH2, Molly Maloy2, Dick Chung, BS1, Sergio A. Giralt, MD3, Ann A. Jakubowski, MD, PhD3, Susan Seo, MD1 and Genovefa A. Papanicolaou, MD1, (1)Infectious Disease Service, Memorial Sloan-Kettering Cancer Center, New York, NY, (2)Memorial Sloan Kettering Cancer Center, New York, NY, (3)Adult Bone Marrow Transplantation Service, Memorial Sloan-Kettering Cancer Center, New York, NY

    Disclosures:

    U. Jongwutiwes, None

    K. Xiao, None

    M. Maloy, None

    D. Chung, None

    S. A. Giralt, None

    A. A. Jakubowski, None

    S. Seo, None

    G. A. Papanicolaou, None

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