Increasing Resistance of Acinetobacter Species to Imipenem in United States Hospitals, 1999-2006

A dangerous pathogen, Acinetobacter, is growing more resistant to antibiotics and increasingly common in U.S. hospitals. This article explores both national and regional trends in rates of Acinetobacter resistance to imipenem, an antibiotic often reserved as a last-line treatment for infections.
Using data from 300 hospitals around the country, this analysis looked at 47,415 Acinetobacter species isolates and their susceptibility against imipenem over the period 1999 to 2006.

Key Findings:

  • There was a more than 300 percent increase in the proportion of Acinetobacter cases resistant to the antibiotic imipenem during 1999 to 2006.
  • Imipenem-susceptible isolates decreased from 94.1 percent of all tested isolates in 1999 to 72.4 in 2006.
  • Eight out of nine U.S. regions showed decreased imipenem susceptibility.
  • Eight regions had imipenem susceptibility of less than 85 percent by 2006.
  • Overall, the East South Central region was the only region not showing a significant decrease in imipenem susceptibility.

The authors conclude that discussions of disease control ought to consider resistant Acinetobacter a high priority and point to the need for a comprehensive solution to the problem of antibiotic resistance to address this growing public health threat, such as more rigorous infection control on a regional basis. In addition, drug companies must be given incentives to develop novel antibiotics that can destroy these resistant strains.