Skip directly to site content Skip directly to page options Skip directly to A-Z link Skip directly to A-Z link Skip directly to A-Z link
Volume 17, Number 6—June 2011
Dispatch

High Vancomycin MIC and Complicated Methicillin-Susceptible Staphylococcus aureus Bacteremia

Jose Maria AguadoComments to Author , Rafael San-Juan, Antonio Lalueza, Francisca Sanz, Joaquin Rodríguez-Otero, Carmen Gómez-Gonzalez, and Fernando Chaves
Author affiliations: Author affiliations: University Hospital 12 de Octubre, Madrid, Spain

Main Article

Table 1

Differential characteristics of patients with bacteremia caused by MSSA strains with a MIC to vancomycin >1.5 µg/mL compared with <1.5 µg/mL by Etest, Hospital 12 de Octubre, Madrid, Spain, January 2002–December 2004*

Characteristic MIC <1.5, n = 76 MIC >1.5, n = 23 p value
Mean age, y (SD) 63.55 (16.7) 62.9 (18.8) 0.87
M/F, % 69.7/30.3 56.5/43.5 0.36
Co-morbidity Charlson Index, mean (SD)
 2.76 (2.7)
 3.4 (3.7)
 0.4
Previous valvular prosthesis 1 (1.3) 2 (8.7) 0.23
Other previous endovascular prosthesis 4 (5.3) 1 (4.3) 0.7
Previous osteoarticular prosthesis 3 (3.9) 0 0.79
Previous renal failure requiring hemodialysis
 7 (9.2)
 4 (17.4)
 0.47
Type of IV catheter as the source of bacteremia
Peripheral line 34 (44.7) 9 (39.1) 0.71
Transitory central catheter 34 (44.7) 10 (43.5) 0.82
Permanent central catheter
 8 (10.6)
 4 (17.4)
 0.76
Vancomycin MIC of the first MSSA isolate, median (range)
 1.2 (0.5–1.4)
 1.5 (1.5–1.7)
 <0.0001
Initial treatment with glycopeptides 46 (60.5) 18 (78.3) 0.19
Initial treatment with antistaphylococcal β-lactams† 20 (26.3) 5 (21.7) 0.87
Initial treatment with non–β-lactam anti-staphylococcal agents‡ 7 (9.2) 0 0.29
Delay in initiation of active antibiotic treatment, d,§ mean (SD) 0.85 (1.06) 1.3 (1.6) 0.14
Duration of antibiotic treatment, d, mean (SD)
 13.4 (8.24)
 18.6 (12)
 0.07
Prompt IV catheter removal¶ 62 (81.6) 17 (73.9) 0.45
Conservative IV catheter management#
 4 (5.3)
 2 (8.7)
 0.32
Development of severe sepsis/septic shock
 11 (14.5)
 5 (21.7)
 0.69
Complicated bacteremia 10 (13.2) 18 (78.3) <0.0001
Septic thrombophlebitis 5 (6.6) 8 (34.9) 0.002
Endocarditis 3 (3.9) 4 (17.3) 0.08
Osteoarticular 2 (2.6) 2 (8.7) 0.48
Pulmonary emboli 0 2 (8.7) 0.08
Other
 0
 2 (8.7)
 0.08
Crude 30-day death rate 8 (10.5) 6 (26.1) 0.13
Attributable death rate 3 (3.9) 4 (17.4) 0.083

*Values are no. (%) except as indicated. MSSA, methicillin-susceptible Staphylococcus aureus; IV, intravenous.
†Antistaphylococcal β-lactams refers to parenteral cloxacillin, cefazolin, amoxicillin-clavulanate, piperacillin-tazobactam, or imipenem/meropenem.
‡Including non–β-lactam antibiotics with in vitro activity against MSSA (mostly levofloxacin, moxifloxacin or, clindamycin).
§Delay since isolation of MSSA in blood cultures.
¶Removal of catheter in the first 48 hours since isolation of MSSA in blood cultures.
#Catheter kept at least 7 days since isolation of MSSA in blood cultures.

Main Article

References
  1. Lodise  TP, Graves  J, Evans  A, Graffunder  E, Helmecke  M, Lomaestro  BM, Relationship between vancomycin MIC and failure among patients with methicillin-resistant Staphylococcus aureus bacteremia treated with vancomycin. Antimicrob Agents Chemother. 2008;52:3315–20. DOIPubMedGoogle Scholar
  2. Moise  PA, Sakoulas  G, Forrest  A, Schentag  JJ. Vancomycin in vitro bactericidal activity and its relationship to efficacy in clearance of methicillin-resistant Staphylococcus aureus bacteremia. Antimicrob Agents Chemother. 2007;51:2582–6. DOIPubMedGoogle Scholar
  3. Sakoulas  G, Moise-Broder  PA, Schentag  J, Forrest  A, Moellering  RC Jr, Eliopoulos  GM. Relationship of MIC and bactericidal activity to efficacy of vancomycin for treatment of methicillin-resistant Staphylococcus aureus bacteremia. J Clin Microbiol. 2004;42:2398–402. DOIPubMedGoogle Scholar
  4. Schwaber  MJ, Wright  SB, Carmeli  Y, Venkataraman  L, DeGirolami  PC, Gramatikova  A, Clinical implications of varying degrees of vancomycin susceptibility in methicillin-resistant Staphylococcus aureus bacteremia. Emerg Infect Dis. 2003;9:657–64.PubMedGoogle Scholar
  5. Soriano  A, Marco  F, Martinez  JA, Pisos  E, Almela  M, Dimova  VP, Influence of vancomycin minimum inhibitory concentration on the treatment of methicillin-resistant Staphylococcus aureus bacteremia. Clin Infect Dis. 2008;46:193–200. DOIPubMedGoogle Scholar
  6. Pillai  SK, Wennersten  C, Venkataraman  L, Eliopoulos  G, Moellering  R, Karchmer  A. Development of reduced vancomycin susceptibility in methicillin-susceptible Staphylococcus aureus. Clin Infect Dis. 2009;49:1169–74. DOIPubMedGoogle Scholar
  7. Walsh  TR, Bolmstrom  A, Qwarnstrom  A, Ho  P, Wootton  M, Howe  RA, Evaluation of current methods for detection of staphylococci with reduced susceptibility to glycopeptides. J Clin Microbiol. 2001;39:2439–44. DOIPubMedGoogle Scholar
  8. Tenover  FC, Moellering  RC Jr. The rationale for revising the Clinical and Laboratory Standards Institute vancomycin minimal inhibitory concentration interpretive criteria for Staphylococcus aureus. Clin Infect Dis. 2007;44:1208–15. DOIPubMedGoogle Scholar
  9. Lalueza  A, Chaves  F, San Juan  R, Daskalaki  M, Otero  JR, Aguado  JM. Is high vancomycin minimum inhibitory concentration a good marker to predict the outcome of methicillin-resistant Staphylococcus aureus bacteremia? J Infect Dis. 2010;201:311–2. DOIPubMedGoogle Scholar
  10. Lalueza  A, Chaves  F, San Juan  R, Daskalaki  M, López-Medrano  M, Lizasoain  M, Less severity but higher risk of late complications in methicillin-resistant Staphylococcus aureus bacteremia with a vancomycin MIC ≥1.5 µg/mL. In: Microbiology ASF, editor. 49th Interscience Conference on Antimicrobials Agents and Chemotherapy. San Francisco: American Society for Microbiology; 2009.
  11. Stryjewski  ME, Szczech  LA, Benjamin  DK Jr, Inrig  JK, Kanafani  ZA, Engemann  JJ, Use of vancomycin or first-generation cephalosporins for the treatment of hemodialysis-dependent patients with methicillin-susceptible Staphylococcus aureus bacteremia. Clin Infect Dis. 2007;44:190–6. DOIPubMedGoogle Scholar
  12. Cui  L, Ma  X, Sato  K, Okuma  K, Tenover  FC, Mamizuka  EM, Cell wall thickening is a common feature of vancomycin resistance in Staphylococcus aureus. J Clin Microbiol. 2003;41:5–14. DOIPubMedGoogle Scholar
  13. Peleg  AY, Monga  D, Pillai  S, Mylonakis  E, Moellering  RC Jr, Eliopoulos  GM. Reduced susceptibility to vancomycin influences pathogenicity in Staphylococcus aureus infection. J Infect Dis. 2009;199:532–6. DOIPubMedGoogle Scholar
  14. Chaves  F, Garcia-Martinez  J, de Miguel  S, Sanz  F, Otero  JR. Epidemiology and clonality of methicillin-resistant and methicillin-susceptible Staphylococcus aureus causing bacteremia in a tertiary-care hospital in Spain. Infect Control Hosp Epidemiol. 2005;26:150–6. DOIPubMedGoogle Scholar

Main Article

Page created: August 03, 2011
Page updated: August 03, 2011
Page reviewed: August 03, 2011
The conclusions, findings, and opinions expressed by authors contributing to this journal do not necessarily reflect the official position of the U.S. Department of Health and Human Services, the Public Health Service, the Centers for Disease Control and Prevention, or the authors' affiliated institutions. Use of trade names is for identification only and does not imply endorsement by any of the groups named above.
file_external