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A Bauernfeind

Publications and source records attributed to A Bauernfeind.

At least 19 recordsLinked to original sources
PubMed1998

[Imipenem resistance in Pseudomonas aeruginosa].

In 1997 in western Austria, 9.9% of Pseudomonas aeruginosa strains from patients of general practitioners were resistant to imipenem as well as 18.2% of the isolates from hospitals and 20.2% of the strains at a university teaching hospital. Within the hospital the imipenem resistance varied from 9.9% among out-patients to 28.7% in isolates from intensive care units. In medical/surgical words, up to 15.1% of P. aeruginosa strains were resistant to imipenem. The incidence of imipenem-resistant P. aeruginosa strains correlates to the use of carbapenems. In June 1997, 10 consecutive isolates from 8 patients were obtained and typed using restriction fragment length polymorphism analysis (RFLP) and Pyocin typing. All 10 isolates were resistant to meropenem as well as to imipenem. The finding (by RFLP and Pyocin typing) of individual bacterial types in each isolate strongly contradicts the spread of infection by cross infection. However, all patients were proven to have been treated with imipenem during the 3 months prior to testing. In 1997, 13,880 g of imipenem were used at the university hospital in Innsbruck. The use of carbapenems appears to be the main cause for the increased incidence of imipenem-resistant P. aeruginosa strains.

Austria↗
PubMed1998

Placebo-controlled, double-blind, randomized study of aerosolized tobramycin for early treatment of Pseudomonas aeruginosa colonization in cystic fibrosis.

In chronic Pseudomonas aeruginosa pulmonary infection of patients with cystic fibrosis (CF), antibiotic therapy generally fails to eradicate the bacterial pathogen. The mucoid bacterial phenotype, high sputum production by the host, and low airway levels of antibiotics seem to be responsible for the observed decrease in antibiotic efficacy. We hypothesized that early antibiotic treatment by inhalation in CF patients may be able to prevent or at least delay airway infection. In a prospective placebo-controlled, double-blind, randomized multicenter study, 22 CF patients received either 80 mg b.i.d. of aerosolized tobramycin or placebo for a period of 12 months shortly after the onset of P. aeruginosa pulmonary colonization. Two patients in the tobramycin and six patients in the placebo group stopped inhalation before the 12 month treatment period. Using life table analysis, the time to conversion from a P. aeruginosa-positive to a P. aeruginosa-negative respiratory culture was significantly shorter in the tobramycin-treated group than in the placebo group (P < 0.05, log rank test). Lung function parameters and markers of inflammation did not change in either group during treatment. The results of this study suggest that early tobramycin inhalation may prevent and/or delay P. aeruginosa pulmonary infection in CF patients.

Administration, Inhalation↗
PubMed1998

Ceftazidime-resistant Enterobacteriaceae isolates from three Polish hospitals: identification of three novel TEM- and SHV-5-type extended-spectrum beta-lactamases.

Twelve ceftazidime-resistant isolates of the family Enterobacteriaceae (11 Klebsiella pneumoniae isolates and 1 Escherichia coli isolate) were collected in 1995 from three Polish hospitals located in different cities. All were identified as producers of extended-spectrum beta-lactamases (ESBLs). Detailed analysis of their beta-lactamase contents revealed that six of them expressed SHV-5-like ESBLs. The remaining six were found to produce three different TEM enzymes, each characterized by a pI value of 6.0 and specified by new combinations of amino acid substitutions. The amino acid substitutions compared to the TEM-1 beta-lactamase sequence were Gly238Ser, Glu240Lys, and Thr265Met for TEM-47; Leu21Phe, Gly238Ser, Glu240Lys, and Thr265Met for TEM-48; and Leu21Phe, Gly238Ser, Glu240Lys, Thr265Met, and Ser268Gly for TEM-49. The new TEM beta-lactamases, TEM-47, TEM-48, and TEM-49, belong to a subfamily of TEM-2-related enzymes. Genes coding for TEM-47 and TEM-49 could have originated from the TEM-48-encoding sequence by various single genetic events. The new TEM derivatives probably document the already advanced microevolution of ESBLs ongoing in Polish hospitals, in a majority of which no monitoring of ESBL producers was performed before 1996.

Bacterial Proteins↗
PubMed1998

Cefotaxime-resistant Enterobacteriaceae isolates from a hospital in Warsaw, Poland: identification of a new CTX-M-3 cefotaxime-hydrolyzing beta-lactamase that is closely related to the CTX-M-1/MEN-1 enzyme.

A group of cefotaxime-resistant Citrobacter freundii and Escherichia coli isolates were collected by a clinical laboratory in a hospital in Warsaw, Poland, in July 1996. Detailed analysis has shown that all of these produced a beta-lactamase (pI, 8.4) belonging to the CTX-M family, one of the minor extended-spectrum beta-lactamase families with a strong cefotaxime-hydrolyzing activity. Sequencing has revealed that C. freundii isolates produced a new CTX-M-3 enzyme which is very closely related to the CTX-M-1/MEN-1 beta-lactamase, sporadically identified in Europe over a period of 6 years. Amino acid sequences of these two beta-lactamases differ at four positions: Val77Ala, Asp114Asn, Ser140Ala, and Asn288Asp (the first amino acid of each pair refers to CTX-M-1/MEN-1 and second refers to CTX-M-3). The partial sequence of the E. coli CTX-M gene was identical to the corresponding region of bla(CTX-M-3), but a transconjugant of the E. coli isolate expressed higher levels of resistance to beta-lactams than did C. freundii transconjugants. These resistance differences correlated with differences in plasmid DNA restriction patterns. Our results suggest that CTX-M genes have been spread among different species of the family Enterobacteriaceae in the hospital and that the CTX-M-3-expressing C. freundii strain causing routine urinary tract infections has been maintained for a relatively long time in the hospital environment.

Amino Acid Sequence↗
PubMed1998

Molecular procedure for rapid detection of Burkholderia mallei and Burkholderia pseudomallei.

A PCR procedure for the discrimination of Burkholderia mallei and Burkholderia pseudomallei was developed. It is based on the nucleotide difference T 2143 C (T versus C at position 2143) between B. mallei and B. pseudomallei detected in the 23S rDNA sequences. In comparison with conventional methods the procedure allows more rapid identification at reduced risk for infection of laboratory personnel.

Base Sequence↗
PubMed1998

Discrimination of Burkholderia gladioli from other Burkholderia species detectable in cystic fibrosis patients by PCR.

A procedure for molecular identification of Burkholderia gladioli is described. Specific 16S and 23S rRNA gene signature sequences were defined as primers for PCR. The method allows rapid and specific discrimination of B. gladioli from related species (B. cepacia, B. multivorans, B. vietnamiensis, B. mallei, B. pseudomallei, Ralstonia pickettii, and R. eutropha) and should contribute to the clarification of its role as a human pathogen, e.g., in cystic fibrosis.

Base Sequence↗
PubMed1998

[Frequency and antibiotic susceptibility of oxacillin resistant Staphylococcus aureus in a teaching hospital].

From October 1993 till October 1994, 115 oxacillin resistant Staphylococus aureus strains were isolated in the laboratory of a teaching hospital. This was 2.4% of all of the Staphylococcus aureus strains. The bacteria were isolated from 30 patients, 7 medical personnel and in the environment of the infected patients. Most of the isolates were cultured from blood cultures, wound swabs and drains. If the referring hospitals has been informed about the MRSA status of the patients, several transmissions could have been prevented. In 10 infected patients, the MRSA strains were isolated from the nose, throat and hands. The isolates were also found on the hands of several personnel and in the patients environment, suggesting that the strains had been widely spread. The MRSA strains predominated in the medical and surgical intensive care units and in 2 general surgical wards. They were only found sporadically in other departments (Ophthalmology, Gynaecology, Paediatrics and Urology). MRSA-strains were more resistant to imipenem, ofloxacin, gentamicin, trimethoprim-sulfamethoxazole, tetracycline, erythromycin and clindamycin as oxacillin-sensitive Straphylococcus aureus strains. Genotyping (Restriction-Fragment-Length-Polymorphism) revealed six different strain patterns. The same RFLP types were mainly found on different wards. We conclude that various clones of MRSA may have emerged independently within one hospital and that their spread between wards was remarkably limited. Subsequent intensive hygiene measures have been successful in reducing the number of new isolates.

Anti-Bacterial Agents↗
PubMed1997

Decrease in nosocomial pneumonia in ventilated patients by selective oropharyngeal decontamination (SOD).

OBJECTIVE: To determine the influence of selective oropharyngeal decontamination (SOD) on the rate of colonization and infection of the respiratory tract in intensive care patients requiring mechanical ventilation for more than 4 days. A financial assessment was also performed. DESIGN: Randomized, prospective, controlled study using amphotericin B, colistin sulfate (polymyxin E), and tobramycin applied to the oropharynx and systemic cefotaxime prophylaxis. SETTING: Anesthesiology intensive care unit (ICU) of a 1500-bed hospital. PATIENTS: A total of 88 patients admitted as emergencies and intubated within less than 24 h were enrolled. Fifty-eight patients received SOD and 30 patients served as controls. Randomization was in the proportion of 2 : 1 study patients to controls. INTERVENTIONS: Microbiological samples from the oropharynx and other infected sites were taken at the time of admission, then twice a week and after extubation. MEASUREMENTS AND RESULTS: With the use of SOD, colonization was significantly reduced. Furthermore, the infection rate decreased from 77% in the controls to 22% in the study patients. Staphylococcus aureus was the main potential pathogen causing colonization and pneumonia. Number of days in the ICU, duration of ventilation, and mortality were not significantly decreased. The total cost of antibiotics was reduced. Development of resistance was not observed. CONCLUSIONS: The use of SOD significantly reduced the colonization and pneumonia and the total charge for antibiotics. The length of stay in the ICU, duration of ventilation, and mortality were similar. No resistance was observed. Staphylococcus aureus was selected by SOD in some patients and the clinical relevance needs further observation.

Adult↗
PubMed1997

Comparison of the antibacterial activities of the quinolones Bay 12-8039, gatifloxacin (AM 1155), trovafloxacin, clinafloxacin, levofloxacin and ciprofloxacin.

The in-vitro activities of the quinolones Bay 12-8039, gatifloxacin (AM 1155), trovafloxacin, clinafloxacin, levofloxacin and ciprofloxacin were compared. Gram-positive cocci were most susceptible to Bay 12-8039, clinafloxacin and trovafloxacin; Enterobacteriaceae and fastidious organisms were most susceptible to clinafloxacin [corrected]; Pseudomonas spp. were most susceptible to clinafloxacin and ciprofloxacin; anaerobes, Helicobacter pylori and Campylobacter jejuni were most susceptible to gatifloxacin, clinafloxacin and trovafloxacin. Against gram-positive cocci, the only agents that were more active than ciprofloxacin were those carrying an azabicyclo (trovafloxacin, Bay 12-8039), 3-amino-pyrrolidinyl (clinafloxacin) or 3-methyl-piperazinyl (gatifloxacin) moiety at position C7.

Anti-Infective Agents↗
PubMed1997

A novel class C beta-lactamase (FOX-2) in Escherichia coli conferring resistance to cephamycins.

An Escherichia coli strain resistant to a broad spectrum of beta-lactams, including cephamycins, was isolated from a patient suffering from urinary tract infection. A resistance plasmid (pMVP-7) was transferred from the clinical isolate to an Escherichia coli recipient. Both strains produce a cefoxitin-hydrolyzing beta-lactamase focusing at pI 6.7. The phenotype was similar to that of a Klebsiella pneumoniae strain producing cephamycinase FOX-1, so primers were selected from the FOX-1 sequence to amplify the bla gene of the transconjugant. The PCR product obtained was sequenced. The percentage of identity of the deduced amino acid sequence with sequences of other AmpC-type beta-lactamases was 96.9% with FOX-1, 74.9% with CMY-1, and 67.7% with MOX-1. This new plasmid-mediated enzyme is most closely related to FOX-1 (11 amino acid exchanges). We therefore propose the designation FOX-2.

Adult↗
PubMed1996

A multinational European survey on the in-vitro activity of rufloxacin and other comparative antibiotics on respiratory and urinary bacterial pathogens.

The antibacterial activity of rufloxacin was confirmed against a large number of respiratory and urinary tract pathogens collected in five European countries. In terms of both MIC90 values and percentages of susceptible isolates found, this new quinolone showed useful in-vitro activity against Mycoplasma catarrhalis, Haemophilus influenzae and Klebsiella pneumoniae, with a large proportion of Staphylococcus aureus also covered, while, as expected Streptococcus pneumoniae and Streptococcus pyogenes were not included in its antibacterial spectrum. Rufloxacin was comparable with the other antibiotics against these pathogens with the exception of streptococci. Against these microorganisms, beta-lactams were the most active agents. Against the urinary pathogens the in-vitro activity of rufloxacin is similar to that of norfloxacin although this latter drug is more active in terms of MIC90 values and in percentages of strains inhibited. In many cases more isolates were susceptible to the remaining comparator agents than to rufloxacin. However, there were no significant differences between the numbers of microorganisms inhibited by the various drugs and rufloxacin. The findings of this survey do not seem to modify the general picture which emerged in previous studies and further confirms its useful spectrum in different geographic settings.

Anti-Bacterial Agents↗
PubMed1996

Antibiotic susceptibility patterns of respiratory isolates of Klebsiella pneumoniae in Europe and the USA in 1992 and 1993. The Alexander Project Collaborative Group.

The overall antibiotic susceptibility of Klebsiella pneumoniae isolates collected in 1992 (n = 35) and 1993 (n = 85) was highly variable ranging from 0.8% for amoxycillin to 95.8% for ceftriaxone. On a weight for weight basis, the activity of the compounds decreased in the following sequence: ceftriaxone, cefixime, co-trimoxazole, ciprofloxacin, ofloxacin, cefaclor, amoxycillin/clavulanate, doxycycline, cefuroxime, chloramphenicol, amoxycillin. A small percentage of resistant strains was found for each of the compounds (between 0.8% for ceftriaxone and 12.5% for chloramphenicol) with the exception of amoxycillin which was almost uniformly resistant. There was a trend for the percentage of resistant strains to increase between the two study years for all compounds except for chloramphenicol. Resistance to beta-lactams in France and the USA is likely to have been due to strains producing extended spectrum beta-lactamases.

4-Quinolones↗
PubMed1996

Characterization of the plasmidic beta-lactamase CMY-2, which is responsible for cephamycin resistance.

The phenotype of Klebsiella pneumoniae HEL-1 indicates a plasmidic cephamycinase gene (blaCMY-2). Its sequence shows one open reading frame coding for a protein of 381 amino acids. CMY-2 is classified as class C beta-lactamase that is closely related to the plasmidic enzymes BIL-1 and LAT-1 and the chromosomal AmpC of Citrobacter freundii. The blaCMY-2 gene possibly was translocated onto a plasmid of C. freundii which spread to K. pneumoniae.

Amino Acid Sequence↗
PubMed1996

Sequences of beta-lactamase genes encoding CTX-M-1 (MEN-1) and CTX-M-2 and relationship of their amino acid sequences with those of other beta-lactamases.

Amino acid sequences determined either by protein sequencing or by DNA sequencing are identical for cefotaximases CTX-M-1 and MEN-1, whereas CTX-M-2 is 84% identical to CTX-M-1/MEN-1. Both beta-lactamases are distantly related to other plasmidic class A enzymes (homology to TEM-1 is 38.1% for CTX-M-1/MEN-1 and 36.5% for CTX-M-2); the closest relationship was with the chromosomal beta-lactamase of Klebsiella oxytoca E23004 (homologies of 74.5% for CTX-M-1/MEN-1 and 77.9% for CTX-M-2). The cefotaximases CTX-M-1/MEN-1 and CTX-M-2 represent two members of a new subgroup of plasmidic class A beta-lactamases.

Amino Acid Sequence↗
PubMed1996

Characterization of beta-lactamase gene blaPER-2, which encodes an extended-spectrum class A beta-lactamase.

Plasmidic extended-spectrum beta-lactamases of Ambler class A are mostly inactive against ceftibuten. Salmonella typhimurium JMC isolated in Argentina harbors a bla gene located on a plasmid (pMVP-5) which confers transferable resistance to oxyiminocephalosporins, aztreonam, and ceftibuten. The beta-lactamase PER-2 (formerly ceftibutenase-1; CTI-1) is highly susceptible to inhibition by clavulanate and is located at a pI of 5.4 after isoelectric focusing. The blaPER-2 gene was cloned and sequenced. The nucleotide sequence of a 2.2-kb insert in vector pBluescript includes an open reading frame of 927 bp. Comparison of the deduced amino acid sequence of PER-2 with those of other beta-lactamases indicates that PER-2 is not closely related to TEM or SHV enzymes (25 to 26% homology). PER-2 is most closely related to PER-1 (86.4% homology), an Ambler class A enzyme first detected in Pseudomonas aeruginosa. An enzyme with an amino acid sequence identical to that of PER-1, meanwhile, was found in various members of the family Enterobacteriaceae isolated from patients in Turkey. Our data indicate that PER-2 and PER-1 represent a new group of Ambler class A extended-spectrum beta-lactamases. PER-2 so far has been detected only in pathogens (S. typhimurium, Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis) isolated from patients in South America, while the incidence of PER-1-producing strains so far has been restricted to Turkey, where it occurs both in members of the family Enterobacteriaceae and in P. aeruginosa.

Amino Acid Sequence↗
PubMed1996

Comparative characterization of the cephamycinase blaCMY-1 gene and its relationship with other beta-lactamase genes.

A plasmidic beta-lactamase which hydrolyzed cephamycins was first detected and reported in 1989. At that time its description was restricted to phenotypic characteristics. We analyzed nucleotide sequence of its gene and explored it genetic relationship with other bla genes. The deduced amino acid sequence of the blaCMY-1 product was compared with those of other known plasmidic cephamycinases and of chromosomal AmpC beta-lactamases. The results indicate that the relationship of CMY-1 is closest to MOX-1 among the plasmidic cephamycinases and to AmpC of Pseudomonas aeruginosa among the chromosomal cephalosporinases. We conclude that the plasmidic cephamycinases described up to now may be classified into three families, as follows: CMY-1, MOX-1, and FOX-1 with AmpC of P. aeruginosa; CMY-2, BIL-1 and LAT-1 with AmpC of Citrobacter freundii; and MIR-1 with AmpC of Enterobacter cloacae. Plasmidic cephamycinases are now recognized as clinically relevant class C beta-lactamases.

Amino Acid Sequence↗