Prediction of methicillin-resistant Staphylococcus aureus in patients with non-nosocomial pneumonia.
BACKGROUND
Methicillin-resistant Staphylococcus aureus (MRSA) is recognized as an important cause of not only hospital acquired pneumonia, but also non-nosocomial pneumonia. However, the risk factors for non-nosocomial MRSA pneumonia are not clearly defined. Our objective was to identify risk factors at admission that were associated with non-nosocomial MRSA pneumonia.


METHODS
We evaluated 943 patients admitted to a university-affiliated hospital with culture-positive bacterial pneumonia developed outside the hospital from January 2008 to December 2011. We compared the clinical characteristics between MRSA and non-MRSA pneumonia, and identified risk factors associated with MRSA pneumonia.


RESULTS
Of 943 patients, MRSA was identified in 78 (8.2%). Higher mortality was observed in MRSA than in non-MRSA patients (33.3% vs. 21.5%; P = 0.017). In a logistic regression analysis, MRSA pneumonia was observed more frequently in patients with a previous history of MRSA infection (OR = 6.05; P < 0.001), a PSI score ≥120 (OR = 2.40; P = 0.015), intravenous antibiotic treatment within 30 days of pneumonia (OR = 2.23; P = 0.018). By contrast, non-MRSA pneumonia was observed more often in patients with a single infiltrate on chest radiography (OR = 0.55; P = 0.029).


CONCLUSIONS
Anti-MRSA antibiotics could be considered in hospitalized non-nosocomial patients with several risk factors identified herein. The presence or absence of these factors would provide useful guidance in selecting initial empirical antibiotics.
Division of Pulmonology, Department of Internal Medicine, Severance Hospital, Yonsei University College of Medicine, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-752, Republic of Korea.
Won Jai
WJ
Jung
Young Ae
YA
Kang
Moo Suk
MS
Park
Seon Cheol
SC
Park
Ah Young
AY
Leem
Eun Young
EY
Kim
Kyung Soo
KS
Chung
Young Sam
YS
Kim
Se Kyu
SK
Kim
Joon
J
Chang
Ji Ye
JY
Jung
D000368:Aged; D000369:Aged, 80 and over; D016009:Chi-Square Distribution; D017714:Community-Acquired Infections / Q000175:diagnosis / Q000453:epidemiology* / Q000382:microbiology* / Q000401:mortality; D003428:Cross Infection / Q000175:diagnosis / Q000453:epidemiology / Q000382:microbiology / Q000401:mortality; D005260:Female; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D008297:Male; D055624:Methicillin-Resistant Staphylococcus aureus / Q000302:isolation & purification*; D008875:Middle Aged; D018410:Pneumonia, Bacterial / Q000175:diagnosis / Q000453:epidemiology / Q000382:microbiology* / Q000401:mortality; D011023:Pneumonia, Staphylococcal / Q000175:diagnosis / Q000453:epidemiology* / Q000382:microbiology* / Q000401:mortality; D013902:Radiography, Thoracic; D056910:Republic of Korea; D012189:Retrospective Studies; D012307:Risk Factors; D018709:Statistics, Nonparametric; D016896:Treatment Outcome