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B Korner

Publications and source records attributed to B Korner.

At least 19 recordsLinked to original sources

In vitro antimicrobial susceptibility of Aerococcus urinae to 14 antibiotics, and time-kill curves for penicillin, gentamicin and vancomycin.

Aerococcus urinae is a newcomer in clinical and microbiological practice, causing urinary tract infections, bacteraemia/septicaemia and/or endocarditis. This study presents for the first time an evaluation of the activity of a representative panel of antibiotics against a large number of A. urinae isolates. The in vitro susceptibilities (MICs) of 56 isolates of A. urinae to 14 antibiotics were determined by agar dilution. In general, A. urinae isolates showed little inter-isolate variability, and had low MICs of penicillin, amoxicillin, piperacillin, cefepime, vancomycin and rifampicin. High-level aminoglycoside resistance was not found for any of the isolates. Moderate to good activity was seen with quinolones, erythromycin and tetracycline. Isolates from two patients with endocarditis were studied with time-kill curves for penicillin, gentamicin and vancomycin. Penicillin and vancomycin alone exhibited slow or no bactericidal activity against the two strains. When combining either penicillin or vancomycin with gentamicin, rapid bactericidal activity was obtained for both strains with both combinations. The treatment options for A. urinae seem to include penicillins for less severe cases. In severe cases, i.e. endocarditis, the time-kill investigations suggest a beneficial effect of combination with gentamicin. In the penicillin-allergic patient vancomycin in combination with gentamicin represents the most obvious alternative.

Anti-Bacterial Agents↗

[Aerococcus urinae. A newcomer among pathogenic bacteria in clinical and microbiological practice].

A decade ago we discovered a hitherto unrecognized Aerococcus-like organism (ALO) in urine specimens from patients with urinary tract infection. Further microbiological and clinical investigations enabled us to classify it as a human pathogen also causing urogenic septicaemia and endocarditis, the latter often with lethal outcome. The organism is now designated Aerococcus urinae.

Anti-Bacterial Agents↗

Aerococcus urinae: intraspecies genetic and phenotypic relatedness.

A number of Aerococcus-like organisms were recently recognized as human pathogens. Five Aerococcus-like strains were proposed as members of the new species Aerococcus urinae (with type strain E2 [= NCTC 12142]) on the basis of the results of a 16S rRNA sequence analysis. The intraspecies phenotypic and genetic relatedness of 22 selected A. urinae strains was investigated, and a hitherto unrecognized esculin hydrolysis-positive biotype was identified. A total of 14 of the 15 more common esculin-negative strains exhibited very high DNA relatedness as determined by the hydroxyapatite method (the levels of relatedness were greater than 90% in 55 and 70 degrees C reactions, with 1.5% or less divergence in related sequences). The DNA relatedness among the six esculin-positive strains was more heterogeneous, and two DNA hybridization subgroups were formed. Our results are compatible with the hypothesis that both biotypes are members of the single species A. urinae, which contains two or more genetic subspecies. The putative subspecies have not been formally proposed since they cannot be definitively differentiated. The inclusion of A. urinae in the genus Aerococcus is supported by the results of 16S rRNA sequencing. The rRNA sequence data also is compatible with placing both biotypes in a single species.

Bacteriological Techniques↗

Aerococcus-like organisms: use of antibiograms for diagnostic and taxonomic purposes.

Recently, some Aerococcus-like organisms (ALOs), isolated from urine and blood of elderly patients with urinary tract infection, have been described. In this study ALOs and related taxons were tested for susceptibility by agar diffusion and agar dilution methods to 15 selected antimicrobial agents for diagnostic and taxonomic considerations. ALOs were susceptible to a wide range of antimicrobials including beta-lactams, but resistant to aminoglycosides, sulphonamides, trimethoprim and nalidixic acid. By using tablets containing vancomycin, furazolidone and bacitracin, it was possible to separate ALOs from related taxons. Clustering based on antibiotic susceptibilities showed that there is little similarity between Aerococcus viridans and ALOs.

Anti-Bacterial Agents↗

Bacteremia/septicemia due to Aerococcus-like organisms: report of seventeen cases. Danish ALO Study Group.

Some Aerococcus-like organisms (ALOs) have recently been described in Denmark. The bacteria were originally isolated from the urine of elderly patients with urinary tract infections. Since 1987, we have identified 17 cases of bacteremia/septicemia in which ALOs have been isolated in pure culture of blood; we report the data from these cases. Six of the patients presented with endocarditis, eight presented with urosepticemia, and three presented with septicemia. In all but one of the reports, the urinary tract was suspected as the focus of infection, and ALOs were isolated from the urine of nine patients. All but one patient had predisposing illnesses; these were predominantly of urinary or cardiac origin. Five patients died of their infection, two survived the infection but eventually died during hospitalization, and 10 recovered. All of the patients received adequate antimicrobial therapy.

Aged↗

Aerococcus-like organism, a newly recognized potential urinary tract pathogen.

During the last 10 to 15 years, Aerococcus-like organisms have been isolated from urinary tract specimens from hospitalized patients at Bispebjerg Hospital, Copenhagen, Denmark, with signs of urinary tract infection, and a single strain has been deposited at the National Collection of Type Cultures (NCTC 12142). An additional 63 isolates from the urine specimens of as many patients with suspected urinary tract infection have been identified from seven departments of clinical microbiology in Denmark. Clinical information indicates that this organism may be involved in urinary tract infection. These strains and ten previously collected strains, two of which were from blood cultures, were characterized phenotypically. By comparing the results with data on other gram-positive, catalase-negative cocci or coccobacillary organisms, the identified organisms seem to represent a separate taxon.

Adolescent↗

Urosepticemia and fatal endocarditis caused by aerococcus-like organisms.

Two cases of invasive infections with aerococcus-like organisms (ALO) are presented: an 81-year-old man with fatal endocarditis and a 63-year-old man with urosepticemia. No antigenic relationship was found between ALO and Aerococcus viridans (NCTC 8251) in crossed immunoelectrophoretic assay.

Aged↗

Haemophilus isolated from unusual anatomical sites.

During a 15-year period Haemophilus species were isolated from unusual anatomical sites in 80 patients, mostly adults. The origin of specimens was pus and swabs from suppurative lesions, fluids from serosal cavities and gall bladder, gut content, and blood in cases with a supposed tissue focus. In 17 patients Haemophilus species were isolated in pure culture, in 63 patients in conjunction with other bacteria. 17 patients had gynaecological complaints: bartholinitis, salpingitis, and vaginal discharge. 22 patients had gastrointestinal complaints, comprising 17 with appendicitis, peritonitis following perforation of gastric ulcer, gall-duct infections, and an abscess in the stomach wall, and 5 patients with colonization of the gut. 41 patients had soft tissue and bone infections.

Adolescent↗

Susceptibility testing of Danish isolates of Capnocytophaga and CDC group DF-2 bacteria.

Twelve Capnocytophaga and seven DF-2 strains were tested for their susceptibility to 14 antimicrobial agents using an agar dilution and an agar diffusion method. Twenty-three other antibiotics were evaluated using the diffusion test only. All strains were fully susceptible to penicillin, ampicillin, cefuroxime, cefotaxime, erythromycin, clindamycin, chloramphenicol, doxycycline, rifamycin and ofloxacin using both methods. Clindamycin, rifamycin and cefotaxime were most active. Using agar dilution some strains were susceptible to gentamicin, but agar diffusion showed total resistance. One Capnocytophaga strain was susceptible and another moderately susceptible to metronidazole, other strains were resistant. The agar diffusion test showed that both Capnocytophaga and DF-2 were resistant to most other aminoglycosides, to fosfomycin, polymyxin and trimethoprim. All strains of both taxa were fully susceptible to piperacillin, cefoxitin, imipenem and fusidic acid and showed different susceptibilities to the other agents. Susceptibility testing by means of agar diffusion using an enriched chocolate agar and 5% CO2 atmosphere could be used to test Capnocytophaga and DF-2 strains and gives sufficient accuracy for routine use, when revised inhibition zone breakpoints are employed.

Animals↗

Aerococcus-like organism--an unnoticed urinary tract pathogen.

Aerococci are only occasionally isolated from urinary tract specimens. A 4-month' survey revealed 29 patients suspected of urinary tract infection (UTI), from whom an Aerococcus-like organism (ALO) was isolated in significant numbers from urinary tract specimens and singly in 11 cases. Approximately 0.8% of all urinary tract specimens examined during the period yielded growth of ALO. The median age of patients was 75 years. Half of the patients were found to have conditions predisposing to UTI. 9 of 11 patients without indwelling catheter, having ALO isolated in pure culture from the urine, showed one or more typical signs of UTI (fever, dysuria and/or pollakisuria and pyuria). A phenotypic comparison was made between 29 strains of ALO and 6 related organisms, including Aerococcus viridans, Streptococcus faecium, Streptococcus sanguis, Streptococcus bovis, Streptococcus Group Q and Streptococcus Group R. ALO and A. viridans showed many similarities, but, owing to characteristic differences with regard to colony morphology, biochemical reactions and antibiotic susceptibility pattern, the strains were easily separated.

Catheterization↗

Salmonella infections of the urinary tract.

Infection of the urinary tract is a relatively rare manifestation of salmonellosis, most often seen in elderly and debilitated patients. The literature is reviewed briefly with a focus on the mechanisms whereby the urinary tract may be involved in salmonellosis, i.e. ascending or haematogenous invasion of the urinary tract. Predisposing factors, clinical course, and recommendations for follow-up of patients are commented on. Ten cases of urinary tract infections caused by various Salmonellae illustrate the nosology.

Adult↗

Bacteremia in cirrhosis of the liver.

In a retrospective study the average yearly incidence of bacteremia in cirrhosis patients was found to be 4.5%. This is about 5-7 times higher than in two general materials of all bacteremic patients from the same hospital. There was no difference between the distribution of bacterial strains in the 43 bacteremic cirrhosis patients and the two general materials of all bacteremic patients.

Adult↗