European Journal of Internal Medicine 13 (2002) 31–36 www.elsevier.com / locate / ejim Original article The impact of resistance to methicillin in Staphylococcus aureus bacteremia on mortality a, b b a b c c * D. Talon , M.C. Woronoff-Lemsi , S. Limat , X. Bertrand , M. Chatillon , H. Gil , J.L. Dupond a ` ` Service d’ Hygiene Hospitaliere, CHU Jean Minjoz, Bd Fleming, 25030 Besanc ¸on, France b Pharmacie Centrale, CHU Jean Minjoz, Besanc ¸on, France c ´ Service de Medecine Interne, CHU Jean Minjoz, Besanc ¸on, France Received 1 May 2000; received in revised form 13 August 2001; accepted 20 August 2001 Abstract Background: It is unclear whether methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-sensitive S. aureus (MSSA) differ in virulence. We therefore carried out a prospective study of cases of S. aureus bacteremia over a period of 2 years at our university hospital. We report herein the results of a comparative analysis of the clinical characteristics and mortality rates associated with cases of bacteremia caused by MRSA and MSSA. Methods: Over a 2-year period, we reviewed the medical records of hospitalized patients with blood cultures positive for S. aureus. Demographic characteristics, underlying diseases, diagnosis, clinical features, severity, laboratory findings, antimicrobial treatment, and resistance to methicillin were analyzed as possible risk factors for death attributed to bacteremia. Results: The rate of mortality attributed to bacteremia was 27.3% (27 patients): 13 (43.3%) deaths were recorded for patients infected with MRSA and 14 (20.3%) for patients infected with MSSA ( P50.0339, OR53.00 (1.08–8.46)). Two variables were significantly associated with death within 14 days of the onset of bacteremia in univariate and multivariate analyses after adjusting for antimicrobial treatment: malignant hematologic disease (protective factor; OR50.184 (0.038–0.882)) and resistance to methicillin (risk factor; OR52.97 (1.12–7.88)). Conclusion: This study shows that S. aureus bacteremia has a high mortality rate, especially if the strain involved is methicillin-resistant, regardless of patient age and the efficacy of antimicrobial treatment.  2002 Elsevier Science B.V. All rights reserved. Keywords: Methicillin-resistant Staphylococcus aureus; Bacteremia attributed mortality 1. Introduction Control of the spread of MRSA in hospitals should reduce the risk of hospital-acquired MRSA infection. Since methicillin-resistant Staphylococcus aureus However, some hospital physicians with considerable (MRSA) was first described in 1961 [1], it has emerged as experience of MRSA feel that efforts directed at control- a common cause of nosocomial infection worldwide [2]. ling the latter are misguided. They advance the following MRSA is acquired within hospitals and is chiefly spread arguments: the practical impossibility of applying adequate from one patient to another through contact with the hands control measures, the demonstrable failure of attempts to of hospital personnel [3]. The development of nosocomial control MRSA, the theoretical basis for believing control is infection involves a sequence of events including acquisi- impossible, the detrimental effects of attempting to control tion, establishment of colonization, and progression from MRSA, and the unclear benefits of controlling MRSA in colonization to symptomatic infection [4]. the first place [5]. Nosocomial infections are of importance in terms of patient morbidity, mortality, and incremental hospital costs. In deciding whether or not to control *Corresponding author. Tel.: 133-3-8166-8286; fax: 133-3-8166- MRSA, an important question is whether infections with 8914. E-mail address: daniel.talon@ufc-chu.univ-fcomte.fr (D. Talon). MRSA are more likely to be associated with prolonged 0953-6205 / 02 / $ – see front matter  2002 Elsevier Science B.V. All rights reserved. PII: S0953-6205(01)00189-3