Log in | Register

Effects of systemic antibiotic therapy on bacterial persistence in the respiratory tract of mechanically ventilated patients

Stefan Visscher| Carolina A. M. Schurink| Wilhelmina G. Melsen| Peter J. F. Lucas| Marc J. M. Bonten
Original
Volume 34, Issue 4 / April , 2008

Pages 692 - 699

Abstract

Objective

Bacterial respiratory tract colonization predisposes critically ill patients to intensive care unit (ICU)-acquired infections. It is unclear to what extent systemic antibiotics affect colonization persistence. Persistence of respiratory tract colonization, and the effects of systemic antibiotics hereon, were determined in a cohort of ICU patients.

Design

Clinical and microbiological data were collected from 715 admitted mechanically ventilated ICU patients with bacterial growth documented in respiratory tract samples. First day of colonization, persistence of colonization and antibiotic effects hereon were analyzed for six groups of pathogens: Pseudomonas aeruginosa, Acinetobacter species, Enterobacteriaceae, Staphylococcus aureus, Streptococcus pneumoniae and Haemophilus influenzae. Systemic antibiotics were grouped into ‘effective’ and ‘ineffective’ antibiotics, based on in-vitro susceptibility data for the relevant bacteria. The effects of antibiotics were quantified as relative risk (RR) of bacterial persistence in the absence of effective antibiotics.

Measurements and results

Persistence of colonization differed significantly between pathogens, ranging from 4 days (median) for H. influenzae and Strep. pneumoniae to 8 days for P. aeruginosa. Systemic antibiotics were administered on 7,102 (61%) of patient days. Antibiotic use was associated with non-persistence for all pathogens, except Acinetobacter species and P. aeruginosa. RR for non-persistence (as compared to ineffective or no antibiotics) ranged from 3.1 (95% CI 1.4–6.6) for H. influenzae to 0.5 (0.3–1.0) for Acinetobacter species.

Conclusions

In mechanically ventilated patients, persistence dynamics of bacterial respiratory tract colonization, and the effects of (in-vitro) effective antibiotics hereon, are pathogen-specific.

Keywords

References

  1. Bonten MJM, Bergmans CJJ (1996) Risk factors for pneumonia, and colonization of respiratory tract and stomach in mechanically ventilated ICU patients. Am J Respir Crit Care Med 154:1339–1346
    • View reference on PubMed
  2. Bergmans CJJ, Bonten MJM (1997) Indications for antibiotic use in ICU patients: a one-year prospective surveillance. J Antimicrob Chemother 39:527–535
    • View reference on PubMed
    • View reference on publisher's website
  3. Bigger JW (1944) Treatment of staphylococcal infections with penicillin. Lancet 2:497–500
    • View reference on publisher's website
  4. Kussel E, Kishony R, Balaban NQ, Leibler S (2005) Bacterial persistence: a model of survival in changing environments. Genetics 169:1807–1814
    • View reference on publisher's website
  5. Keren I, Kaldalu N, Spoering A, Wang Y, Lewis K (2004) Persister cells and tolerance to antimicrobials. FEMS Microbiol Lett 230:13–18
    • View reference on PubMed
    • View reference on publisher's website
  6. Schurink CAM, Visscher S, Lucas PJF, Leeuwen HJ van, Buskens E, Hoff RG, Hoepelman IM, Bonten MJM (2007) A Bayesian decision-support system for diagnosing ventilator-associated pneumonia. Intensive Care Med 33:1379–1386
  7. Murray TS, Egan M, Kazmierczak BI (2007) Pseudomonas aeruginosa chronic colonization in cystic fibrosis patients. Curr Opin Pediatr 19:83–88
    • View reference on PubMed
    • View reference on publisher's website
  8. Bergmans DC, Bonten MJ, De Leeuw PW, Stobberingh EE (1997) Reproducibility of quantitative cultures of endotracheal aspirates from mechanically ventilated patients. J Clin Microbiol 35:796–798
    • View reference on PubMed
  9. SPSS Inc., Chicago USA. http://www.spss.com
  10. Gnuplot, interactive data and function plotting utility. http://www.gnuplot.info
  11. Trouillet JL, Chastre J, Vuagnat A, Joly-Guillou ML, Combaux D, Dombret MC, Gibert C (1998) Ventilator-associated pneumonia caused by potentially drug-resistant bacteria. Am J Respir Crit Care Med 157:531–539
    • View reference on PubMed
  12. Verhamme KM, De Coster W, De Roo L, De Beenhouwer H, Nollet G, Verbeke J, Demeyer I, Jordens P (2007) Pathogens in early-onset and late-onset intensive care unit-acquired pneumonia. Infect Control Hosp Epidemiol 28:389–397
    • View reference on PubMed
    • View reference on publisher's website
  13. Sirvent JM, Torres A, El-Ebiary M, Castro P, de Batlle J, Bonet A (1997) Protective effect of intravenously administered cefuroxime against nosocomial pneumonia in patients with structural coma. Am J Respir Crit Care Med 155:1729–1734
    • View reference on PubMed
  14. Ewig S, Torres A, El-Ebiary M, Fàbregas N, Hernández C, González J, Nicolás JM, Soto L (1999) Bacterial colonization patterns in mechanically ventilated patients with traumatic and medical head injury. Am J Respir Crit Care Med 159:188–198
    • View reference on PubMed

Sign In

Connect with ICM

Top 5 Articles Editors Picks Supplement