481. Long-Term Outcome of Patients with Nosocomially Acquired Methicillin-Resistant Staphylococcus aureus (MRSA) Colonization
Session: Poster Session: Hospital-acquired and Transplant Infections
Friday, October 30, 2009: 12:00 AM
Room: Poster Hall A
Background: Serious infections caused by MRSA are often preceded by colonization. This study further characterizes and establishes risk factors for the development of MRSA infections following acquisition of MRSA in the hospital, thus giving support to the idea that interrupting transmissions will ultimately decrease infections.
Methods: We enrolled all patients with negative MRSA nasal screen by PCR on admission and no evidence of MRSA colonization or infection in the previous year that were subsequently found to be colonized or infected with MRSA during their stay or on a discharge MRSA nasal screen by PCR. Patients were followed at our institution for at least one year since their qualifying admission. Patient’s electronic medical records were reviewed retrospectively. Infections were defined according to CDC case definitions.
Results: Eighty-seven patients with nosocomially-acquired MRSA were identified. Of these, 22 (25.27%) patients developed 25 infections during the 12 months following their admission. The infections involved: bloodstream infection (11), wound infections (9), pneumonia (5), and osteomyelitis (1). The time from admission to infection is shown in the figure. Eight patients (32%) developed infections after discharge from the hospital. Infections were more likely in patients with HIV (P<0.003) and those who received fluoroquinolones (OR 4.13 95%CI 1.43-13.0). Diabetes (OR 2.57), care by surgery service (OR 3.53), and admission to the surgical ICU (OR 4.97) also showed a trend towards increased likelihood of infection.
Conclusion: A large proportion of patients who acquire MRSA in the hospital develop an infection. Some of these infections occur months after transmission. Preventing acquisition of MRSA in the hospital will significantly reduce morbidity and associated cost to institutions.
Gio Baracco, MD, Miami Veteran Affairs Medical Center, Nathaniel Duke, MD, Miami VA Healthcare System, Miami, FL and  N. Duke, None..
G. J. Baracco, None.