Elina Jokinen1, Janne Laine1, Reetta Huttunen1, Pekka Rahikka2, Heini Huhtala3, Risto Vuento4, Jaana Vuopio5,6, Jaana Syrjänen1,7. 1. a Department of Internal Medicine , Infectious Disease Unit, Tampere University Hospital , Tampere , Finland. 2. b The Health Centre of Heinola , Doctagon OY , Heinola , Finland. 3. c Faculty of Social Sciences , University of Tampere , Tampere , Finland. 4. d Department of Clinical Microbiology , Fimlab Laboratories , Tampere , Finland. 5. e Department of Infectious Diseases , National Institute for Health and Welfare , Helsinki , Finland. 6. f Department of Medical Microbiology and Immunology , University of Turku , Turku , Finland. 7. g School of Medicine , University of Tampere , Tampere , Finland.
Abstract
BACKGROUND: The aim of this study was to assess the association of methicillin resistance and penicillinase production with clinical characteristics and outcome of Staphylococcus aureus bacteremia. METHODS: For 126 patients with methicillin-resistant Staphylococcus aureus (MRSA) bacteremia, 378 age- and gender-matched controls with methicillin-susceptible Staphylococcus aureus (MSSA) bacteremia were selected. Of controls, 126 had bacteremia caused by penicillin-susceptible strains (PSSA) and 252 by penicillinase-producing strains (PRSA). Underlying diseases, clinical course and mortality were retrospectively assessed. RESULTS: Patients with MRSA bacteremia were more often smokers than patients with MSSA bacteremia (OR 2.34, 95% CI 1.27-4.32). MRSA bacteremia was more often healthcare-associated (OR 4.23, 95% CI 2.47-7.24), associated with central venous catheters (OR 2.09, 95% CI 1.27-3.47), glucocorticoid therapy (OR 1.82, 95% CI 1.12-2.93) and prior surgery (OR 2.32, 95% CI 1.43-3.76). Patients with MRSA bacteremia received appropriate empiric antibiotic (31%) less often than controls (98%). Mortality within 28 days was higher in MRSA bacteremia (26.8%) than in MSSA bacteremia (15.5%) (OR 2.00, 95% CI 1.20-3.34), PRSA bacteremia (17.0%) (OR 1.79 95% CI 1.04-3.09) or PSSA bacteremia (12.5%) (OR 2.56 95% CI 1.27-5.15). The difference remained after adjusting for underlying diseases and foci. There was no significant difference in clinical course between PRSA and PSSA bacteremias. CONCLUSIONS: MRSA bacteremia was associated with poorer outcome than either PRSA or PSSA bacteremia. We corroborated several risk factors found in previous studies.
BACKGROUND: The aim of this study was to assess the association of methicillin resistance and penicillinase production with clinical characteristics and outcome of Staphylococcus aureus bacteremia. METHODS: For 126 patients with methicillin-resistant Staphylococcus aureus (MRSA) bacteremia, 378 age- and gender-matched controls with methicillin-susceptible Staphylococcus aureus (MSSA) bacteremia were selected. Of controls, 126 had bacteremia caused by penicillin-susceptible strains (PSSA) and 252 by penicillinase-producing strains (PRSA). Underlying diseases, clinical course and mortality were retrospectively assessed. RESULTS:Patients with MRSA bacteremia were more often smokers than patients with MSSA bacteremia (OR 2.34, 95% CI 1.27-4.32). MRSA bacteremia was more often healthcare-associated (OR 4.23, 95% CI 2.47-7.24), associated with central venous catheters (OR 2.09, 95% CI 1.27-3.47), glucocorticoid therapy (OR 1.82, 95% CI 1.12-2.93) and prior surgery (OR 2.32, 95% CI 1.43-3.76). Patients with MRSA bacteremia received appropriate empiric antibiotic (31%) less often than controls (98%). Mortality within 28 days was higher in MRSA bacteremia (26.8%) than in MSSA bacteremia (15.5%) (OR 2.00, 95% CI 1.20-3.34), PRSA bacteremia (17.0%) (OR 1.79 95% CI 1.04-3.09) or PSSA bacteremia (12.5%) (OR 2.56 95% CI 1.27-5.15). The difference remained after adjusting for underlying diseases and foci. There was no significant difference in clinical course between PRSA and PSSA bacteremias. CONCLUSIONS: MRSA bacteremia was associated with poorer outcome than either PRSA or PSSA bacteremia. We corroborated several risk factors found in previous studies.