Acinetobacter

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{{Taxobox | color = lightgrey | name = Acinetobacter | regnum = Bacteria | phylum = Proteobacteria | classis = Gamma Proteobacteria | ordo = Pseudomonadales | familia = Moraxellaceae | genus = Acinetobacter | genus_authority = Brisou & Prévot 1954 }} Acinetobacter is a genus of Proteobacteria. It is Gram-negative, non-motile, oxidase-negative, and occurs in pairs under magnification.

1 Identification
2 Description
3 Treatment
4 References

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Identification

Using FLN, or Fluorescence-Lactose-Denitrification medium, to find the amount of acid produced by metabolism of glucose, different species of bacteria under this genus can be identified.

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Description

Species of the genus Acinetobacter, except some of the A. lwoffii strain, grow very well on MacConkey agar. Most Acinetobacters are infectious, and the strain A.baumannii is the most common nosocomial infection in health care centers and military medical facilities. A. baumannii can cause infections including skin and wound infections and pneumonia. It also causes meningitis, but A. lwoffi is mostly responsible for that. A. baumannii can live on human skin or dry surfaces for weeks

Since the start of the Iraq War, over 300 cases of A. baumannii had infected U.S. soldiers in the Middle East. At least five have died.

Ethanol has been found to stimulate the virulence of A. baumannii. Tests on infected nematode worms that were dosed with ethanol found that the worms laid fewer eggs and their life spans were only 80% of worms infected with a version of A. baumannii that didn't respond to ethanol. This study suggests that the common misconception that drinking alcohol kills infections is false and drinking alcohol may actually help the infection to grow. (Smith & Snyder, 2005)

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Treatment

Since bacteria have evolved, most are immune to their first enemy, penicillin, and Acinetobacters are one of these bacteria. Also, they are immune to chloramphenicol, another common antibiotic. Therefore, the most potent treatment against this genus of bacteria is a combination of aminoglycoside and ticarcillin. A dramatic increase in antibiotic resistance in Acinetobacter strains has been reported by the Centers for Disease Control and Prevention (CDC).

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. Among one set of isolates from Walter Reed Army Medical Center, 13 (35%) were susceptible to imipenem only, and two (4%) were resistant to all drugs tested. One antimicrobial agent, colistin (polymyxin E), has been used to treat infections with multidrug-resistant A. baumannii; however, antimicrobial susceptibility testing for colistin was not performed on isolates described in this report. Because A. baumannii can survive on 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.