467. Outcome of MRSA Bacteremia in Cancer Patients Treated with Vancomycin
Session: Poster Session: Hospital-acquired and Transplant Infections
Friday, October 30, 2009: 12:00 AM
Room: Poster Hall A
Background: MRSA-BSI may cause significant morbidity & mortality in patients (pts) with cancer. Data on mortality and efficacy of Vancomycin (Vanc) in cancer pts with MRSA-BSI are lacking.
Methods: We identified 100 cancer pts who developed MRSA-BSI between 8/2004-3/2008. Treatment failures were defined as death secondary to infection while on treatment, persistent BSI &/or fever for >96hrs and metastatic complications. Failure at 60 days was defined as relapse &/or death. Pts with unknown outcomes were excluded from the analysis.
Results: Median age was 60y. (Range: 4-84) and 64% were males. Most pts had hematologic malignancies (HM) (47%); 10% were s/p HSCT. Most pts had sepsis on presentation (90%) & catheter-related bacteremia (CRBSI) (60%). Vanc was 1st line therapy in 94 pts; 77 pts were evaluable. Vanc failure rate was 34/77 (44%). These pts had higher MRSA-associated deaths [8/30 (27%) vs. 3/39 (8%), p<0.001] & higher overall mortality (13/34 (38%) vs. 8/42 (19%), p=0.003) leading to worse 60-d outcome (13/30 (43%) vs. 10/41 (24%) failures, p=0.004). Out of the failures, 19 (56%) pts were switched to an alternative antibiotic. Early switch (≤ 6d) showed higher 60-d success as compared to late switch [7/11 (64%) vs. 3/8 (38%), p=0.005]. A trend towards better 60-d outcome in CRBSI than non- CRBSI was seen [42/60 (70%) vs. 23/40 (57%) success, p= 0.06]. Only 35/82 pts (43%) who had Vanc troughs measured, reached level ≥ 15μg/ml. This group showed higher Vanc failure (64% vs. 39%), worse 60-d outcome (50% vs. 23%) and more nephrotoxicity (20% vs. 0%), (all p<0.001) as compared to low trough group. When compared to solid tumors, HM pts had higher Vanc failure (56% vs. 32%, p=0.001) & worse 60-d outcome (42% vs. 27%, p=0.03).
Conclusion: Our data suggest that antibiotic switch from Vanc at the earliest sign of failure may improve 60-d outcome. Pts who failed Vanc had higher MRSA-associated mortality. An alternative therapy for MRSA-BSI should be considered in pts with HM.
Javier Adachi, MD1, Roy Chemaly, MD, MPH2, Ray Hachem, MD3, Victor Mulanovich, MD4, Issam Raad, MD, Dhanesh Rathod, MD6, Jharna Shah, MD6 and  J. N. Shah, None..
R. Y. Hachem, None..
D. B. Rathod, None..
J. A. Adachi, None..
V. E. Mulanovich, None. 
I. I. Raad,
Cook, Inc. Role(s): Consultant, Research Relationship, Other, Royalties related to technology on which Dr. Raad is an inventor/co-inventor, Consultant, Research Relationship, Other, Royalties related to technology on which Dr. Raad is an inventor/co-inventor, Consultant, Research Relationship, Other, Royalties related to technology on which Dr. Raad is an inventor/co-inventor, Received: Educational Grant, Licensing Agreement or Royalty, Consulting Fee.
R. F. Chemaly,
Cubist Pharmaceuticals Role(s): Speaker's Bureau, Received: Research Grant., (1)Dept. of Infectious Diseases, Infection Control and Employee Health, The University of Texas M. D. Anderson Cancer Center, Houston, TX, (2)Infectious Diseases, Infection Control and Employee Health, University of Texas - MD Anderson Cancer Center, Houston, TX, (3)Infectious Diseases, Infection Control & Employee Health, University of Texas MD Anderson Cancer Center, Houston, TX, (4)University of Texas M.D. Anderson Cancer Center, Houston, TX, (5)The University of Texas M. D. Anderson Cancer Center, Houston, TX

Disclosures:

J. Adachi, None

R. Chemaly, None

R. Hachem, None

V. Mulanovich, None

I. Raad, None

D. Rathod, None

J. Shah, None