Impaired virulence and in vivo fitness of colistin-resistant Acinetobacter baumannii.
نویسندگان
چکیده
Acinetobacter baumannii (American Type Culture Collection strain 19606) acquires mutations in the pmrB gene during the in vitro development of resistance to colistin. The colistin-resistant strain has lower affinity for colistin, reduced in vivo fitness (competition index, .016), and decreased virulence, both in terms of mortality (0% lethal dose, 6.9 vs 4.9 log colony-forming units) and survival in a mouse model of peritoneal sepsis. These results may explain the low incidence and dissemination of colistin resistance in A. baumannii in clinical settings.
منابع مشابه
Impaired virulence and fitness of a colistin-resistant clinical isolate of Acinetobacter baumannii in a rat model of pneumonia.
We compared the fitness and lung pathogenicity of two isogenic clinical isolates of Acinetobacter baumannii, one resistant (ABCR) and the other susceptible (ABCS) to colistin. In vitro, ABCR exhibited slower growth kinetics than ABCS. In a rat model of pneumonia, ABCR was associated with less pronounced signs of infection (lung bacterial count, systemic dissemination, and lung damage) and a bet...
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To the Editor—In an article recently published in the Journal, Lopez-Rojas et al [1] demonstrated that an in vitro mutant of Acinetobacter baumannii resistant to colistin had reduced in vivo fitness and decreased virulence, in terms of both mortality and survival, in a mouse model of peritoneal sepsis. They suggest that the lower in vivo bacterial fitness and decreased virulence of this mutant ...
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عنوان ژورنال:
- The Journal of infectious diseases
دوره 203 4 شماره
صفحات -
تاریخ انتشار 2011