PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Acinetobacter Infections”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 289 records · Page 16Linked to original sources
PubMed2006

Emergence of PER and VEB extended-spectrum beta-lactamases in Acinetobacter baumannii in Belgium.

OBJECTIVES: Strains of Acinetobacter baumannii producing the extended-spectrum beta-lactamase (ESBL) PER-1 are widespread in Turkey and have also been reported from Korea and France. In contrast, A. baumannii producing the ESBL VEB-1 have only been reported from France, where one strain was responsible for a nationwide outbreak in 2003-2004. Here we describe the emergence of strains of A. baumannii producing VEB-1 and PER- 1 in Belgium. METHODS: Belgian hospitals were alerted in December 2003 to the emergence in France of VEB-1-producing A. baumannii susceptible only to meropenem and colistin. Isolates with a compatible susceptibility profile were sent to a single central laboratory for VEB-1 confirmation, molecular characterization and typing. RESULTS: From December 2003 to March 2005, three hospitals located close to the French border and one in the Brussels area reported isolation of eight A. baumannii isolates compatible with the French epidemic clone. Using PCR, six were identified as VEB-1-positive and two as PER-1-positive. All the VEB-1-positive isolates were clonally related by PFGE and by integron analysis to the French epidemic strain. The PER-1-positive strains were indistinguishable by PFGE but not related to the known French isolate or to several Turkish isolates. Both genes were chromosomally encoded. CONCLUSIONS: This work illustrates the inter-country spread of VEB-1-producing A. baumannii isolates as well as the emergence of PER-1-producing A. baumannii strains in Belgium.

Acinetobacter Infections↗
PubMed2004

Acinetobacter baumanii meningitis: a rare complication of incidental durotomy.

Despite the frequency of dural tears in spinal surgery, meningitis is a rare complication reported to occur with a frequency of 0.18%. To the best of our knowledge, no case of Acinetobacter baumanii meningitis has been reported in the literature after a dural tear secondary to lumbar spine discectomy. This case highlights the importance of repairing all dural tears and commencing antibiotics that cover uncommon bacteria in those who develop symptoms of meningitis in this setting.

Acinetobacter Infections↗
PubMedDate not supplied

An unusual cause of septicemia and death in a burn patient: discussion and review.

Sepsis remains a common source of morbidity and mortality for seriously burned patients. Sources of sepsis are varied, although some are dramatically more common than others. Rarely, the burn surgeon may be confronted with an infectious source that remains unelucidated until postmortem examination. This case report describes the hospital course and subsequent death of a severely burned patient with sepsis, the source of which was only discovered on postmortem examination by our county medical examiner.

Acinetobacter Infections↗
PubMed2003

Clinical impact of pneumonia caused by Acinetobacter baumannii in intubated patients: a matched cohort study.

OBJECTIVE: To determine whether ventilator-associated pneumonia caused by Acinetobacter baumannii (VAPAB) is associated with increased mortality rate. DESIGN: A retrospective matched case-control study in which all intensive care unit adult patients with microbiologically documented VAPAB were defined as cases. SETTING: Four intensive care units from teaching hospitals. PATIENTS: Sixty patients were matched to sixty controls. MEASUREMENTS AND MAIN RESULTS: Controls were matched based on stay before pneumonia onset, disease severity (Acute Physiology and Chronic Health Evaluation II) at admission, and diagnostic category. Population characteristics and intensive care unit mortality rates of patients with VAPAB and their controls were compared. Attributable mortality was determined by subtracting the crude mortality rate of the controls from the crude mortality rate of the case patients. Twenty-four of the 60 case patients died, representing a crude mortality rate of 40%, whereas 17 of the 60 controls died, a crude mortality rate of 28.3% (p =.17). Crude intensive care unit mortality was the same (12 of 35, 34.2%) in patients with VAPAB caused by strains sensitive to imipenem and in their matched controls. It was 44% for the 25 patients with imipenem-resistant strains with an estimated attributable mortality rate of 20.0% (95% confidence interval, -5.6% to 45.7%). Mean intensive care unit stay of patients and controls was 35.3 and 36.6 days, respectively (p = nonsignificant). CONCLUSION: In intubated patients, pneumonia by A. baumannii is not significantly associated with attributable mortality rate or an increased length of intensive care unit stay.

Acinetobacter Infections↗
PubMed1999

Genotypic and phenotypic similarity of multiresistant Acinetobacter baumannii isolates in the Czech Republic.

The diversity of 103 clinical isolates of the Acinetobacter calcoaceticus-Acinetobacter baumannii complex obtained between 1991 and 1997 from 17 Czech hospitals was studied by ribotyping, biotyping, plasmid profiling and antibiotic susceptibility testing. According to the EcoRI ribotypes, all but one of these isolates were identified to the DNA group level: 77 isolates were allocated to DNA group 2 (A. baumannii), 14 to DNA group 3, 10 to DNA group 13 sensu Tjernberg and Ursing and one to DNA group 1 (A. calcoaceticus). In total, 50 different EcoRI ribotypes and 10 biotypes were observed. Plasmids were found in 92% of the isolates and a high variability in plasmid profiles was found in isolates of the same DNA group. The combination of typing profiles allowed two predominant groups (termed A and B) to be distinguished among the A. baumannii isolates (37 and eight isolates, respectively) that shared a specific ribotype and were highly similar in other properties. These two groups comprised both sporadic and outbreak isolates and were found in most localities. Group A and B isolates were markedly more resistant to antibiotics than most of the remaining isolates, thus representing 85% of all multiresistant isolates. The features of groups A and B corresponded to those of two epidemic clones identified recently among hospital strains in north-western Europe.

Acinetobacter Infections↗
PubMed2005

Repetitive-DNA-element PCR fingerprinting and antibiotic resistance of pan-European multi-resistant Acinetobacter baumannii clone III strains.

In the present study, it was shown that repetitive-DNA-element PCR fingerprinting using the (GTG)5 primer [(GTG)5-PCR] is a rapid and reliable tool to genotypically differentiate members of the recently described pan-European multi-resistant Acinetobacter baumannii (MAB) clone III from the known MAB clones I and II. The identification of four new representatives of the MAB clone III dating from 1991 to 1993 by (GTG)5-PCR indicates that this clone has persisted in European hospitals since the beginning of the 1990s. Tetracycline (TET) resistance was found to be common among clone III strains, including one strain that also displayed resistance to minocycline. The TET-resistance phenotype in this MAB clone appeared to be strongly associated with the presence of the efflux-type gene tet(A), but the fact that some members lack this gene or have acquired an additional tet gene [i.e. tet(M)] suggests that the tet gene carriage in the pan-European clone III population may have diversified in time and space. In contrast, all clone III strains shared the previously described aminoglycoside resistotype encoded by the aminoglycoside-modifying genes aphA6 and the class 1 integron-associated aadB, which may point to the fact that these genes probably are more stably inherited in MAB clone III compared to tet genes.

Acinetobacter Infections↗
PubMed2004

Colistin efficacy in an experimental model of Acinetobacter baumannii endocarditis.

The in-vivo activity of colistin was evaluated in an experimental rabbit model of Acinetobacter baumannii endocarditis with a strain susceptible to colistin and intermediate to imipenem. Compared to a control group, colistin was effective (p < 0.05) in bacterial clearance from blood and in the sterilisation of blood cultures, but was not effective in clearing A. baumannii from vegetations. Thus, although colistin may be effective in treating bacteraemia caused by susceptible strains of A. baumannii, it may not be a suitable treatment for endocarditis, perhaps because of poor penetration into vegetations and a low C(max)/MIC ratio in tissue.

Acinetobacter Infections↗
PubMed2005

Characterisation of OXA-51, a novel class D carbapenemase found in genetically unrelated clinical strains of Acinetobacter baumannii from Argentina.

Acinetobacter baumannii is now one of the most frequently encountered nosocomial pathogens in intensive therapy units, and is renowned for being difficult to treat because of resistance to most antibiotics. Carbapenems are the remaining drugs of choice in many centres, but carbapenem resistance is now emerging in strains worldwide. Two subgroups of carbapenem-hydrolysing beta-lactamases, which differ in their amino-acid homology, have been found in some resistant strains. This report describes the emergence and characterisation of a novel carbapenemase (OXA-51) in genetically distinct carbapenem-resistant A. baumannii strains from Argentina. Enzyme kinetics and inhibitor studies were performed spectrophotometrically with purified beta-lactamase. Amplification of the gene was achieved with a two-step PCR method employing arbitrary partially degenerate and gene-specific primers. Transfer of imipenem resistance was attempted with the use of broth and membrane filter methods. Attempts to produce plasmid-cured variants were made in ethidium bromide curing experiments. OXA-51 was identified in two clones of A. baumannii, and was found to have < 63% amino-acid identity with subgroups 1 and 2. Enzyme kinetic studies confirmed that OXA-51 was a molecular class D enzyme with carbapenemase activity, and that it displayed the highest affinity for imipenem (Km value 11 microM). Sequence analysis of the gene identified distinct differences within conserved class D motifs when compared with subgroups 1 and 2. Attempts to transfer imipenem resistance and to determine a plasmid location for the gene failed. OXA-51 is the first of a new subgroup of carbapenemases to emerge in multiresistant clinical isolates of A. baumannii.

Acinetobacter Infections↗
PubMed2005

Prevalence of Acinetobacter baumannii and other Acinetobacter spp. in faecal samples from non-hospitalised individuals.

In total, 226 individuals from the community were investigated for faecal carriage of Acinetobacter spp. by broth enrichment culture, followed by growth on blood agar and/or Leeds Acinetobacter Medium (LAM). Acinetobacter baumannii was isolated on both LAM and blood agar from one of 100 specimens in the UK and one of 126 specimens in The Netherlands. The predominant species were Acinetobactor johnsonii and genomic sp. 11, which were cultured from 22 and five specimens, respectively. A. baumannii did not seem to be widespread in the faecal flora of individuals in the community.

Acinetobacter Infections↗
PubMed2005

Pharmacokinetic/pharmacodynamic assessment of the in-vivo efficacy of imipenem alone or in combination with amikacin for the treatment of experimental multiresistant Acinetobacter baumannii pneumonia.

A guinea-pig pneumonia model involving imipenem-susceptible and imipenem-resistant strains of Acinetobacter baumannii was developed to assess the in-vitro and in-vivo activities of imipenem, alone or in combination with amikacin, and the pharmacokinetic and pharmacodynamic parameters. Serum levels were measured by bioassay (imipenem) or immunoassay (amikacin), followed by calculation of pharmacokinetic and pharmacodynamic parameters (Cmax, AUC, t1/2, Cmax/MIC, AUC/MIC, and Deltat/MIC). In-vivo efficacy was evaluated by comparing bacterial counts in the lungs of treatment groups with end-of-therapy controls by anova and post-hoc tests. Decreases in the Cmax (13.4%), AUC (13%), t1/2 (25%) and Deltat/MIC (11.8-32.2%) of imipenem were observed when it was administered with amikacin, compared with administration of imipenem alone. Similarly, decreases in the Cmax (34.5%), AUC (11.6%), Cmax/MIC (34.5%) and AUC/MIC (11.7%) of amikacin were observed when it was administered with imipenem. Bacterial counts in lungs were reduced by imipenem (p 0.004) with the imipenem-susceptible strain, and by amikacin (p 0.001) with the imipenem-resistant strain. The combination of imipenem plus amikacin was inferior to imipenem alone with the imipenem-susceptible strain (p 0.01), despite their in-vitro synergy, and was inferior to amikacin alone with the imipenem-resistant strain (p < 0.0001). In summary, combined use of imipenem with amikacin was less efficacious than monotherapy, probably because of a drug-drug interaction that resulted in decreased pharmacokinetic and pharmacodynamic parameters for both antimicrobial agents.

Acinetobacter Infections↗
PubMed2006

Carbapenem resistance in Acinetobacter baumannii: mechanisms and epidemiology.

The increasing trend of carbapenem resistance in Acinetobacter baumannii worldwide is a concern since it limits drastically the range of therapeutic alternatives. Metallo-beta-lactamases (VIM, IMP, SIM) have been reported worldwide, especially in Asia and western Europe, and confer resistance to all beta-lactams except aztreonam. The most widespread beta-lactamases with carbapenemase activity in A. baumannii are carbapenem-hydrolysing class D beta-lactamases (CHDLs) that are mostly specific for this species. These enzymes belong to three unrelated groups of clavulanic acid-resistant beta-lactamases, represented by OXA-23, OXA-24 and OXA-58, that can be either plasmid- or chromosomally-encoded. A. baumannii also possesses an intrinsic carbapenem-hydrolysing oxacillinase, the expression of which may vary, that may play a role in carbapenem resistance. In addition to beta-lactamases, carbapenem resistance in A. baumannii may also result from porin or penicillin-binding protein modifications. Several porins, including the 33-kDa CarO protein, that constitute a pore channel for influx of carbapenems, might be involved in carbapenem resistance.

Acinetobacter Infections↗
PubMed2006

Genotypic diversity and antibiotic susceptibility of Acinetobacter baumannii isolates in a Bulgarian hospital.

A set of 18 Acinetobacter baumannii isolates, collected prospectively in a Bulgarian hospital during episodes of increased A. baumannii occurrence during 2000-2002, was investigated for genotypic diversity and antibiotic susceptibility. Four genotypes were identified by amplified fragment length polymorphism genomic fingerprinting, one of which (type 1) accounted for 13 isolates, indicating that a specific strain was predominant. The single isolate allocated to type 2 was identified to European clone I. All isolates were resistant to multiple antibiotics, but most retained susceptibility to tobramycin and colistin, and all except one were susceptible to imipenem.

Acinetobacter Infections↗
PubMed2006

Pyrosequencing for rapid identification of carbapenem-hydrolysing OXA-type beta-lactamases in Acinetobacter baumannii.

Carbapenem-resistant Acinetobacter baumannii isolates producing carbapenem-hydrolysing oxacillinases are emerging worldwide. These enzymes are divided into four phylogenetic subgroups: OXA-23-like, OXA-51-like, OXA-24-like and OXA-58-like. A PCR-based approach linked to pyrosequencing analysis was developed to identify the genes for these beta-lactamases. Carbapenem-hydrolysing oxacillinases were rapidly and unambiguously identified in a collection of carbapenem-resistant clinical isolates of A. baumannii and Acinetobacter junii. Pyrosequencing may provide a rapid tool for identification of OXA variants, thus avoiding delays inherent in classical sequencing methods.

Acinetobacter↗