Acinetobacter spp, opportunistic strains of bacteria, are widely distributed in nature. Generally considered nonpathogenic to healthy individuals, several species persist in hospital environments and cause severe, life-threatening infections in immune-compromised patients.
The spectrum of antibiotic resistances of these organisms, together with their survival capabilities, make them a threat to hospitals, as documented by recurring outbreaks both in highly developed countries and elsewhere.
Acinetobacter spp are frequently isolated in intensive care units, where both sporadic cases as well as epidemic and endemic occurrences are common.A. baumannii is a frequent cause of nosocomial pneumonia, especially of late-onset ventilator associated pneumonia, and can cause various other infections, including skin and wound infections, bacteremia, and meningitis.
Because A. baumannii can survive on dry surfaces for up to 20 days, they pose a high risk of spread and contamination in hospitals, potentially putting immune-compromised and other patients at risk for drug-resistant infections that are often fatal and generally expensive to treat.
In November 2004, the CDC reported an increasing number of A. baumannii bloodstream infections in patients at military medical facilities in which service members injured in the Iraq/Kuwait region during Operation Iraqi Freedom (OIF) and in Afghanistan during Operation Enduring Freedom (OEF) were treated. Most of these were multidrug-resistant.
Acinetobacter species are innately resistant to many classes of antibiotics, including penicillin, chloramphenicol, and often aminoglycosides. A dramatic increase in antibiotic resistance in Acinetobacter strains has been reported by the Centers for Disease Control, and the carbapenems are recognised as the gold-standard and/or treatment of last resort.