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Medline ® Abstracts for References 5,8-10

of 'Acinetobacter infection: Epidemiology, microbiology, pathogenesis, clinical features, and diagnosis'

5
TI
Epidemiology and infection control implications of Acinetobacter spp. in Hong Kong.
AU
Houang ET, Chu YW, Leung CM, Chu KY, Berlau J, Ng KC, Cheng AF
SO
J Clin Microbiol. 2001;39(1):228.
 
In a previous study, we showed that Acinetobacter genomic DNA group 3 was the most common species among blood culture isolates and was commonly found on superficial carriage sites of the healthy and the sick, which are different findings from those reported in Europe and North America. We used amplified ribosomal DNA restriction analysis and pulsed-field gel electrophoresis to study further the molecular epidemiology of acinetobacters in our region. Over a study period of 6 weeks with 136 consecutive routine clinical isolates (1.33% of all specimens), genomic DNA groups 2 (Acinetobacter baumannii), 3, and 13TU were obtained from 59 of 69 positive patients. There is a significant difference in the specimen sources of the three genomic DNA groups, with group 13TU being significantly associated with the respiratory tract (chi-square exact test, P = 0.0064). Settle plates showed a significantly heavier environmental load from the intensive care unit (ICU) than from the four surgical wards examined (22 of 70 versus 76 of 120 plates with<5 colonies; chi-square test, P<0. 0001). Genomic group 3 accounted for 6 of 12 clusters of possibly related strains among patients, between patients and the ICU environment, and in the ICU environment. Genomic groups 2 and 3 accounted for 21% of the 132 genomically identified isolates recovered from 21 of 41 local vegetables, 53 of 74 fish and meat samples, and 22 of 60 soil samples. Group 13TU was present only in patients' immediate surroundings. The role played by the environment and by human carriage should be evaluated in order to devise a cost-effective infection control program pertinent to our situation of acinetobacter endemicity.
AD
Department of Microbiology, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin NT, Hong Kong SAR, People's Republic of China. ehouang@cuhk.edu.hk
PMID
8
TI
Antibiotic resistance of gram-negative bacteria in rivers, United States.
AU
Ash RJ, Mauck B, Morgan M
SO
Emerg Infect Dis. 2002;8(7):713.
 
Bacteria with intrinsic resistance to antibiotics are found in nature. Such organisms may acquire additional resistance genes from bacteria introduced into soil or water, and the resident bacteria may be the reservoir or source of widespread resistant organisms found in many environments. We isolated antibiotic-resistant bacteria in freshwater samples from 16 U.S. rivers at 22 sites and measured the prevalence of organisms resistant to beta-lactam and non-beta-lactam antibiotics. Over 40% of the bacteria resistant to more than one antibiotic had at least one plasmid. Ampicillin resistance genes, as well as other resistance traits, were identified in 70% of the plasmids. The most common resistant organisms belonged to the following genera: Acinetobacter, Alcaligenes, Citrobacter, Enterobacter, Pseudomonas, and Serratia.
AD
Department of Biology, Washburn University, Topeka, KS 66621, USA. zzash@washburn.edu
PMID
9
TI
Validation of partial rpoB gene sequence analysis for the identification of clinically important and emerging Acinetobacter species.
AU
Gundi VA, Dijkshoorn L, Burignat S, Raoult D, La Scola B
SO
Microbiology. 2009 Jul;155(Pt 7):2333-41. Epub 2009 Apr 23.
 
Bacteria belonging to the genus Acinetobacter are ubiquitous in soil and water. Only a few species, including Acinetobacter baumannii, and the unnamed Acinetobacter genomic species (gen. sp.) 3 and 13TU, which together with the soil organism Acinetobacter calcoaceticus are combined in the A. calcoaceticus-A. baumannii (Acb) complex, have been recognized as important nosocomial infectious agents. The ecology, epidemiology and pathology of most species are not yet well established. Lack of practical and accurate methods limits routine identification of clinical isolates and thus hampers precise identification of those of the Acb complex and other Acinetobacter species of possible clinical significance. We previously identified a 350 bp highly variable zone on the rpoB gene which appeared to be a promising target for rapid molecular identification. In the present study, we validated this method for accuracy on a collection of reference strains belonging to A. calcoaceticus (5 strains), Acinetobacter gen. sp. 3 (29 strains), A. gen. sp. 13TU (18 strains), A. baumannii (30 strains) and one strain each of A. radioresistens, A. gen. sp. 15TU, A. gen. sp. 10, A. gen. sp. 11, A. gen. sp. 'between 1 and 3' and A. gen. sp. 14TU=13BJ. This represents the largest analysis to date that compares a large number of well-identified strains of the Acb complex to assess the intra- and interspecies variation within this complex. All were correctly identified with 98.9-100 % intraspecies relatedness based on partial rpoB sequence analysis. We then applied this tool to identify 99 Acinetobacter clinical isolates from four public hospitals in Marseille, France. All isolates could easily be identified to species as they were separated into 13 species sequence types with a sequence variance of 0-2.6% from their respective type strains. Of these 99 isolates, 10 were A. haemolyticus, 52 were A. baumannii, 27 were A. gen. sp. 3, 5 were A. schindleri, 1 was A. lwoffii, and 1 was A. gen. sp. 13TU. Three were provisionally identified as A. gen. sp. 9. This is the first work to identify all specimens of a set of clinical Acinetobacter isolates at species level using rpoB sequence analysis. Our data emphasize the recognition of A. schindleri as an emerging cause of Acinetobacter-related infection and confirm that A. gen. sp. 3 is the second most commonly isolated Acinetobacter species after A. baumannii in patients.
AD
Unitédes Rickettsies, CNRS UMR 6236, Facultéde Médecine de Marseille, 13385 Marseille Cedex 05, France.
PMID
10
TI
Reservoirs of Acinetobacter baumannii outside the hospital and potential involvement in emerging human community-acquired infections.
AU
Eveillard M, Kempf M, Belmonte O, Pailhoriès H, Joly-Guillou ML
SO
Int J Infect Dis. 2013 Oct;17(10):e802-5. Epub 2013 May 11.
 
The objective of the present report was to review briefly the potentially community-acquired Acinetobacter baumannii infections, to update information on the reservoirs of A. baumannii outside the hospital, and to consider their potential interactions with human infections. Most reports on potentially community-acquired A. baumannii have been published during the last 15 years. They concern community-acquired pneumonia, infections in survivors from natural disasters, and infected war wounds in troops from Iraq and Afghanistan. Although the existence of extra-hospital reservoirs of A. baumannii has long been disputed, the recent implementation of molecular methods has allowed the demonstration of the actual presence of this organism in various environmental locations, in human carriage, in pets, slaughter animals, and human lice. Although the origin of the A. baumannii infections in soldiers injured in Southwestern Asia is difficult to determine, there are some arguments to support the involvement of extra-hospital reservoirs in the occurrence of community-acquired infections. Overall, the emergence of community-acquired A. baumannii infections could be associated with interactions between animals, environment, and humans that are considered to be potentially involved in the emergence or re-emergence of some infectious diseases.
AD
Laboratoire de Bactériologie - Hygiene, Centre Hospitalier Universitaire, 4 rue Larrey, 49000 Angers, France; Groupe d'Etude des Interactions Hôtes Pathogènes (GEIHP), Universitéd'Angers, France. Electronic address: MaEveillard@chu-angers.fr.
PMID