No abstract available.
Acinetobacter calcoaceticus* ; Acinetobacter* ; Pneumonia*

Members of the genus Acinetobacter are recognized as newer pathogens of the nosocomial infection with an increasing frequency in recent years. Strains that belonged to A. calcoaceticus-A. baumannii complex (genomic species 1, 2, 3, and 13TU) were major groups associated with nosocomial infection. Phenotypic identification was unreliable and laborious method to classify Acinetobacter strains into 19 genomic species. Rapid and reliable identification of clinical isolates is essential to diagnosis and epidemiology of Acinetobacter. We investigated the suitability of amplified ribosomal DNA restriction analysis (ARDRA) to identify genomic species of 131 Acinetobacter isolates. The 16S rRNA genes (ribosomal DNA) were enzymatically amplified and the amplified PCR products were restricted independently with the enzymes, AluI, CfoI, and MboI. Genomic species of Acinetobacter was classified by the combinations of restriction patterns. The analysis was showed that restriction profiles were characteristic for each genomic species. One hundred fourteen isolates were identified as A. baumannii, twelve were identified as genomic species 13TU, and one was identified as genomic species 3. Four isolates were found to be unknown organisms. All of the isolates which were identified to A. baumannii by phenotypic tests were completely discriminated into A. baumannii and genomic species 13TU by ARDRA. This study demonstrates that ARDRA is a rapid and simple techniques for the identification of Acinetobacter species according to the genomic species.
Acinetobacter baumannii* ; Acinetobacter calcoaceticus* ; Acinetobacter* ; Cross Infection ; Diagnosis ; DNA, Ribosomal* ; Epidemiology ; Genes, rRNA ; Polymerase Chain Reaction

Acinetobacter species encounters frequently with clinical specimens and now accounts for a substantial proportion of endemic nosocomial infections in Korea. Recent trends indicate that the antimicrobial resistant strains of Acinetobacter species are increasing. Sixty-one strains were isolated from specimens of patients suspected of nosocomial infections during 1991 to 1996. At present, phenotypic identification of Acinetobacter using biochemical test may not be reliable and resulted in the difficulty to clarify the source of infections and epidemiological study of hospital-acquired infections. Aware of the importance of rational taxonomic proposal for these isolates, correct species identification of these organisms by molecular typing method was carried out. A total of fifty-four strains of A. calcoaceticus-A. baumannii complex species which were identified to genospecies 2 and 13 by biochemical characteristics was subjected to identify by ribotyping using restriction endonuclease EcoRI, ClaI, and SalI. Of fifty-four strains, twenty-five strains were identified as A. baumannii (genospecies 2) and twenty-one strains as genospecies 13, and six strains changed to genospecies 3, and the rest two strains were confirmed as A. haemolyticus (genospecies 4). This result suggests that the ribotyping may be of value for identification of genospecies and epidemiological information of Acinetobacter strains.
Acinetobacter baumannii* ; Acinetobacter calcoaceticus* ; Acinetobacter* ; Cross Infection ; DNA Restriction Enzymes ; Humans ; Korea ; Molecular Typing ; Ribotyping*

No abstract available.
Acinetobacter baumannii* ; Acinetobacter* ; Pneumonia*

We collected 76 clinical isolates of Acinetobacter baumannii (amikacin MIC by Vitek 2 AST-N055 card: < or =2microgram/mL, 11 isolates; 4microgram/mL, 19 isolates; 8microgram/ mL, 17 isolates; 16microgram/mL, 27 isolates; and > or =64microgram/ mL, 2 isolates) from a university hospital and evaluated the Vitek 2 AST-N055 card vs the broth microdilution as a reference method for testing susceptibility to amikacin. Vitek 2 AST-N055 card yielded very major errors in 15 isolates (19.7%) and minor errors in 26 isolates (34.2%). Of the 15 isolates shown very major errors, 14 had Vitek 2 MICs ranging from 8 to 16microgram/mL. The results of our study suggest strongly that it is unreliable to test the amikacin susceptibility by Vitek 2 AST-N055 card of A. baumannii with the Vitek 2 MICs ranging from 8 to 16microgram/mL. In those cases, another susceptibility test, such as broth microdilution (BMD), should be performed to confirm the results.
Acinetobacter ; Acinetobacter baumannii ; Amikacin

Aims: The aim of this research is to explore the presence of multidrug-resistance (MDR) Acinetobacter baumannii strains isolated from hospitalized patients in a tertiary-care center, Subang Jaya, Selangor, Malaysia and to compare their genotypic and phenotypic characteristics. Methodology and results: Clonal relationships were determined by multilocus sequence typing (MLST) and biofilm forming ability was evaluated by using 2, 3 - bis (2 - methoxy - 4 - nitro - 5-sulfophenyl) - 5 - [(phenylamino) carbonyl] - 2H-tetrazolium hydroxide (XTT) reduction assay in microplates and Congo red agar method (CRA). Four virulence genes coding for A. baumannii pilus usher-chaperone assembly protein, csuE gene; outer membrane protein, ompA gene; biofilm poly-β-1, 6-Nacetylglucosamine (PNAG) synthesis protein, pgaA gene; and acinetobactin-mediated iron acquisition protein, bauA gene were searched for in a collection of strains. Antimicrobial resistance against 11 antibiotics were studied by broth microdilution method. Seventeen A. baumannii clinical strains were isolated and MLST showed that the strains belonged to 5 distinct sequence types (STs), namely, ST-6, ST-265, ST-324, ST-325 and ST-432. Fiftythree percent of the strains were resistant to 4 or more antibiotics. Twelve strains produced biofilm and out of them, 4 were strong biofilm producer, besides, these strong biofilm producers were MDR strains and belongs to ST-6. In addition, all strains were ompA positive, biofilm producing strains were csuE and pgaA positive and only strong biofilm producing strains were bauA positive. Conclusion, significance and impact study: Our study demonstrates that the ST-6 strains in Malaysia could represent MDR, capable of forming strong biofilm and possess csuE, ompA, pgaA and bauA genes, virulence characteristics that probably help the bacteria to persist and cause infection.
Acinetobacter baumannii

OBJECTIVEGas chromatography (GC) was used to investigate the cellular fatty acid (CFA) composition of 141 Acinetobacter baumannii and 32 A. calcoaceticus isolates from different locations in China and to find chemical markers to differentiate these two closely related bacteria.

METHODSWhole cell fatty acid methyl esters (FAMEs) were obtained by saponification, methylation, and extraction for GC analysis, followed by a standardized Microbial Identification System (MIS) analysis.

RESULTSAll A. baumannii and A. calcoaceticus strains contained some major fatty acids, namely, 18:1 ω9c, 16:0, Sum In Feature 3, 12:0, 17:1ω8c, 3-OH-12:0, 17:0, Sum In Feature 2, 2-OH-12:0, and 18:0 compounds. Although most of the total CFAs are similar between A. baumannii and A. calcoaceticus strains, the ratios of two pairs of CFAs, i.e., Sum In Feature 3/18:1 ω9c versus 16:0/18:1 ω9c and Sum In Feature 3/18:1 ω9c versus unknown 12.484/18:1 ω9c fatty acids, could differentiate these two closely related bacteria. A. baumannii could be easily classified into two subgroups by plotting some ratios such as Sum In Feature 3/16:0 versus 17:0 and Sum In Feature 3/2-OH-12:0 versus 17:0 fatty acids.

CONCLUSIONThe ratios of some CFAs could be used as chemical markers to distinguish A. baumannii from A. calcoaceticus.

Acinetobacter baumannii ; classification ; cytology ; metabolism ; Acinetobacter calcoaceticus ; classification ; cytology ; metabolism ; Biomarkers ; metabolism ; Fatty Acids ; metabolism ; Species Specificity

No abstract available.
Acinetobacter baumannii* ; Acinetobacter* ; Hospitals, General* ; Imipenem* ; Korea*

No abstract available.
Acinetobacter baumannii ; Acinetobacter ; Colistin ; Solanum tuberosum

No abstract available.
Acinetobacter baumannii* ; Intensive Care Units*