Acinetobacter

Epidemiology

  • Outbreaks of Acinetobacter in ICU’s are usually due to multi-drug resistant organisms
  • Resistance can rapidly develop to tetracyclines, fluoroquinolones, aminoglycosides, and beta-lactams
  • Risk Factor for Development of Acinetobacter VAP: prior antibiotic use

Organisms

  • Acinetobacter baumanii
  • Acinetobacter calcoaceticus: isolation from the lung of mechanically ventilated patient with VAP portends a worse prognosis

Diagnosis

  • xxx

Clinical

Treatment

  • Colistin (see Polymyxins): approximately 98% of Acinetobacter strains are susceptible to Colistin
  • Rifampin (see Rifampin): monotherapy is not recommended, as resistance develops quickly
    • Rifampin is only effective when given in combination with Colistin
  • Prolonged Carriage of Organism: a substantial proportion of patients infected with Acinetobacter remain carriers of the organism for a prolonged period
    • Long-term contact isolation is recommended

References

  • Naas T et al. VEB-1 extended-spectrum beta-lactamase-producing Acinetobacter baumannii, France. Emerg Infect Dis 2006;12:1214
  • Marchaim D et al. Surveillance cultures and duration of carriage of multidrug- resistant Acinetobacter baumannii. J Clin Microbiol 2007;45:1551
  • Bassetti M et al. Colistin and rifampicin in the treatment of multidrug-resistant Acinetobacter baumannii infections. J Antimicrob Chemother 2008;61:417.
  • Munoz-Price LS, Weinstein RA. Acinetobacter infection. New Engl J Med 2008;358(12):1271-1281
  • Enoch DA, et al. Investigation and management of an outbreak of multidrug-carbapenem-resistant Acinetobacter baumannii in Cambridge, UK. J Hosp Infect 2008;70(2):109-18.
  • Monterrubio-Villar J, et al. Outbreak of multi-resistant Acinetobacter baumannii in a polyvalent intensive care unit: clinical, epidemiological analysis and PFGE-printing evolution. Eur J Clin Microbiol Infect Dis 2009;28(10):1281-4