An Emergence of Multidrug Resistant Nosocomial Pathogen- Acinetobacter Baumannii

Abstract

Acinetobacter baumannii is gram negative, coccobacillus which is ubiquitous in hospital environments. In 1911, Martinis Willem Bergerinck, a Dutch Microbiologist discovered a gram negative, oxidase negative, non-fermentative organism named Micrococcus calcoaceticus from soil on a calcium acetate mineral medium, later on known to be in genus Acinetobacter [1,2]. In 1968 Baumann et al. [3] published comprehensive study on different organisms comprising a single genus, and then the genus Acinetobacter was widely accepted [3]. In late 1970s, Acinetobacter began to be recognized as a nosocomial pathogen [4]. In 1986, Bouvet and Grimont used DNA-DNA hybridization methods to propose 4 new species of Acinetobacter, including Acinetobacter baumannii. According to Wong Acinetobacter baumannii has the ability to persist longer on dry surfaces under nutrient limiting conditions. They have observed that under such conditions the cell wall becomes thicker making it more persistence. This results into rapid transmission in hospitals and other natural environmental [5]. Certain outbreaks studies have revealed that few colonies of strains of Acinetobacter baumannii can remain viable for certain months to years on solid surfaces especially nosocomial surfaces [6]. Acinetobacter baumannii are known as "Iraqibacter" as it was found present in wound infections in soldiers returned from Iraq and Afghanistan. A. baumannii has gained attention in last few years because of its multidrug resistance properties which make its potential nosocomial pathogen [1]. Here a comprehensive review is prepared to summaries recent information and development related to A. baumannii. It has given special emphasized on infections, risk factors, pathogenesis, genetic aspects for virulence and mechanism of antibiotic resistance. Prevalence of A. Baumannii in various diseasesAs described earlier, A. baumannii infections has more prevalence in the patients who are hospitalized due to critical illness, who has serious underlying diseases, who were subjected to invasive and surgical procedures and who were treated with broad spectrum antibiotics for longer duration [7]. It is seen that most of A. baumannii infections involve fluid rich organ systems such as urinary tract, respiratory tract and peritoneal cavity. The most common infections are pneumonia, urinary tract infection, meningitis and trauma. A. baumannii can cause Crimson PublishersWings to the Research