381. Clinical Outcomes of Patients with HAP/VAP due to PVL(+) vs. PVL(-) MRSA: Results from the IMPACT-HAP Study
Session: Poster Session: Hospital-acquired and Transplant Infections
Friday, October 30, 2009: 12:00 AM
Room: Poster Hall A
Background: Controversy exists regarding the role of Panton-Valentine leukocidin (PVL) toxin in the virulence of MRSA. The objective of this study was to compare the clinical outcomes of patient with HAP/VAP infected with MRSA PVL(+) vs. PVL(-).
Methods: A secondary analysis of the IMPACT-HAP database was performed. CDC definition of HAP and VAP was followed. USA genotype, SCCmec type, and presence of PVL gene was performed in all MRSA isolates. CA-MRSA was defined as USA 300, SCCmec type IV, PVL (+). Severity of disease was evaluated by APACHE II score. Clinical outcome was mortality at 30 days.
Results: A total of 65 cases of MRSA HAP/VAP were identified. The incidence of PVL(+) MRSA was 35%. APACHE II score at diagnosis of HAP/VAP was 20 ±7 for PVL(+) MRSA and 19.5 ±7 for PVL(-) MRSA (p value 1.00). Mortality was 13% (3/23) for patients with PVL(+) MRSA versus 28.6% (12/42) for patients with PVL(-) MRSA (p value 0.16).
Conclusion: One third of HAP/VAP cases in our study were caused by MRSA PVL(+). The increased severity of disease and poor patient outcomes reported with MRSA PVL(+) causing CAP are not evident when cases of MRSA PVL(+) are compared to PVL(-) as the etiology of HAP/VAP. Lack of expression of the PVL gene in patients with HAP/VAP may explain the similar outcomes for MRSA PVL(+) and PVL(-).
Marty Allen, MD1, Patricio Cabral, MD2, Kimbal Ford, PharmD3, Martin Gnoni, MD1, Daniel Kett, MD4, Julie Mangino, MD5, Mehdi Mirsaeidi, MD1, Paula Peyrani, MD, Julio Ramirez, MD1, Ernesto Scerpella, MD7, the IMPACT-HAP Study Group, Marcus Zervos, MD8 and  M. Allen, None..
M. Mirsaeidi, None..
P. Cabral, None..
M. Gnoni, None. 
P. Peyrani,
Pfizer, Inc Role(s): Investigator, Received: Research Support.
J. Mangino,
Pfizer, Inc Role(s): Investigator, Received: Research Support.
M. Zervos,
Pfizer, Inc Role(s): Investigator, Received: Research Support.
D. Kett,
Pfizer, Inc Role(s): Investigator, Received: Research Support.
K. Ford,
Pfizer, Inc Role(s): Employee, Received: Salary.
E. Scerpella,
Pfizer, Inc Role(s): Employee, Received: Salary.
J. Ramirez,
Pfizer, Inc Role(s): Investigator, Received: Research Support., (1)University of Louisville, Louisville, KY, (2)Division of Infectious Diseases, University of Louisville, Louisville, KY, (3)Pfizer, Inc, Louisville, KY, (4)Jackson Memorial Hospital, Louisville, KY, (5)Ohios State University, Louisville, KY, (6)P, Louisville, KY, (7)Infectious Disease, Henry Ford Hospital, Detroit, MI