Infective endocarditis in patients after percutaneous pulmonary valve implantation with the stent-mounted bovine jugular vein valve: Clinical experience and evaluation of the modified Duke criteria.

AIMS: Percutaneous pulmonary valve implantation (PPVI) has proven good hemodynamic results. As infective endocarditis (IE) remains a potential complication with limited available clinical data, we reviewed our patient records to improve future strategies of IE prevention, diagnosis and treatment. METHODS: Medical records of all patients diagnosed with Melody® valve IE according to the modified Duke criteria were retrospectively analyzed in three Belgian tertiary centers. RESULTS: 23 IE episodes in 22 out of 240 patients were identified (incidence 2.4% / patient year) with a clear male predominance (86%). Median age at IE was 17.9 years (range 8.2-45.9 years) and median time from PPVI to IE was 2.4 years (range 0.7-8 years). Streptococcal species caused 10 infections (43%), followed by Staphylococcus aureus (n = 5, 22%). In 13/23 IE episodes a possible entry-point was identified (57%). IE was classified as definite in 15 (65%) and as possible in 8 (35%) cases due to limitations of imaging. Echocardiography visualized vegetations in only 10 patients. PET-CT showed positive FDG signals in 5/7 patients (71%) and intracardiac echocardiography a vegetation in 1/1 patient (100%). Eleven cases (48%) had a hemodynamically relevant pulmonary stenosis at IE presentation. Nine early and 6 late percutaneous or surgical re-interventions were performed. No IE related deaths occurred. CONCLUSIONS: IE after Melody® valve PPVI is associated with a relevant need of re-interventions. Communication to patients and physicians about risk factors is essential in prevention. The modified Duke criteria underperformed in diagnosing definite IE, but inclusion of new imaging modalities might improve diagnostic performance.

Use of the polymerase chain reaction (PCR) for the detection of aacA genes encoding aminoglycoside-6'-N-acetyltransferases in reference strains and gram-negative clinical isolates from two Belgium hospitals.

Genes encoding aminoglycoside 6'-N-acetyltransferases, were identified using the polymerase chain reaction (PCR). Four sets of primers delineating DNA fragments of 209 bp, 250 bp, 260 bp and 347 bp, specific for the four known aacA genes, and probes within these fragments, were constructed based on the nucleotide sequences of the aacA genes. The specificity of the primers was evaluated using reference strains encoding various aminoglycoside-modifying enzymes. The primers reacted with their corresponding aacA genes and did not cross-react with genes coding for other aminoglycoside-modifying enzymes. One hundred and sixty-one aminoglycoside resistant clinical isolates showing AAC(6')I activity were tested using the PCR assays. The gene described by Tran Van Nhieu & Collatz (1987) was the most frequently identified aacA gene. One strain of Citrobacter freundii contained two distinct aacA genes. However, in 46% of the strains, the majority being Serratia spp. and Acinetobacter spp. none of the specific amplified DNA fragments for any of the known aacA genes could be detected.

Serotypes and extended spectrum beta-lactam resistance in aminoglycoside resistant Pseudomonas aeruginosa isolates from two Belgian general hospitals: a seven year study.

A total of 1896 isolates of Pseudomonas aeruginosa resistant to aminoglycosides and isolated during the period 1983-1989 in two Belgian general hospitals were included in this study. The most frequently encountered O serotypes were O4, O11, O12 and non-typable isolates. The majority of the isolates showed resistance to extended spectrum beta-lactam antibiotics (cefotaxime, ceftriaxone and cefepime). However, a low degree of resistance was found for ceftazidime. By contrast, amikacin and isepamicin, remained active on a significant number of aminoglycoside resistant isolates. In both hospitals, impermeability and AAC(3)II enzyme production were the most prevalent aminoglycoside resistance mechanisms. There were marked differences between the two hospitals with regard to the distribution of the O-serotypes and resistance profiles.

Activity of cefotiam in combination with beta-lactam antibiotics on enterobacterial hospital strains.

By using checkerboard titrations the effect of cefotiam combined with different beta-lactam antibiotics on fifty strains of Enterobacteriaceae moderately susceptible (minimal inhibiting concentration greater than or equal to 8 mg/l) or resistant (minimal inhibiting concentration greater than or equal to 64 mg/l) to cefotiam was evaluated. The following compounds were tested: cefamandole, cefazolin, cefmenoxime, cefotaxime, cefotiam, ceftazidime, cefuroxime, mecillinam and piperacillin. The synergistic effect varied markedly. The combination cefotiam-mecillinam showed the highest rate of synergistic activity. Antagonism was found in 1% of the combinations.

[Antibacterial activity of carumonam and cefpirome on hospital strains resistant to gentamicin and cephalothin: comparison with other beta-lactam antibiotics, new fluoroquinolones, aminoglycosides and other antibiotics]. / Activité antibactérienne du carumonam et du cefpirome sur des souches hospitalières résistantes à la gentamicine et la céfalotine:comparaison avec d'autres bêta-lactamines, de nouvelles fluoroquinolones, aminoglycosides et d'antibiotiques divers.

The antibacterial in vitro activity of carumonam, a new monobactam, and cefpirome, a new cephalosporin, was studied on 483 hospital strains resistant to gentamicin and cephalothin, in comparison with amikacin, azlocillin, aztreonam, cefmenoxim, cefoperazone, cefotaxim, cefsulodin (for Pseudomonas), ceftazidime, ceftriaxone, cefuroxim, chloramphenicol, ciprofloxacin, doxycycline, enoxacin, netilmicin, norfloxacin, pefloxacin, piperacillin, rifampicin, tobramycin and trimethoprim. In general the two compounds have a very good in vito activity on Enterobacteriaceae but are less active on non-fermenting microorganisms. For the Enterobacteriaceae the minimal inhibitory concentrations 90% for carumonam was less than or equal to 1.1 mg/l excepted for Enterobacter spp. (43,6 mg/l) and M. morganii (56.8 mg/l) . All the Enterobacteriaceae are susceptible to cefpirome (minimal inhibitory concentrations 90% less than or equal to 5.3 mg/l). The activity of carumonam and cefpirome on Enterobacteriaceae is comparable with that of the third generation cephalosporins. Carumonam is more active than cefpirome and other beta-lactams, ceftazidime excepted, on Pseudomonas aeruginosa and Pseudomonas spp. On the other hand, both compounds reveal to have only a low activity on the other non-fermenters which minimal inhibitory concentrations 90% values of 115.4 mg/l for carumonam and 32.0 mg/l for cefpirome.

Three-year survey of amikacin use and aminoglycoside resistance in a general hospital in Belgium.

The aim of the study was to evaluate the effect of intensive use of amikacin on the resistance levels to amikacin, gentamicin, tobramycin, netilmicin and dibekacin. The base-line resistance in the preamikacin phase (three months of amikacin use less than 1%; 676 isolates) was 1.0% for amikacin, 11.4% for gentamicin, 8.0% tobramycin, 6.2% for netilmicin and 8.3% for dibekacin. During the amikacin phase (36 months of average amikacin use of 89%; 6048 isolates) there was no significant change in aminoglycoside resistance except for dibekacin (from 8.3% to 10.9%, 0.05 greater than p greater than 0.02). Isolated amikacin resistance was not observed.

[In vitro bacteriostatic and bactericidal effect of ciprofloxacin and others quinolone derivatives on Campylobacter jejuni]. / L'activité bactériostatique et bactéricide in vitro de la ciprofloxacine ainsi que d'autres dérivés quinoloniques contre les Campylobacters jejuni.

The in vitro bacteriostatic (MIC) and bactericidal (MBC) activities of ciprofloxacin and seven other quinolone derivatives on Campylobacter jejuni from human origin were determined. Ciprofloxacin, pefloxacin and rosoxacin exhibited the best bacteriostatic and bactericidal activities. For the three compounds the MIC90 was less than or equal to 0.33 microgram/ml while the MBC90 was resp. 0.36, 0.56 and 0.56 microgram/ml. The MBC values were always significantly higher than the MIC values (P less than 0.001). An attempt was made to select strains with an induced resistance against the quinolone derivatives.

The comparative activity of pefloxacin, enoxacin, ciprofloxacin and 13 other antimicrobial agents against enteropathogenic microorganisms.

In this study, we compared the activity of pefloxacin, enoxacin and ciprofloxacin against 269 enteropathogenic strains (Campylobacter jejuni, enteropathogenic Escherichia coli, Salmonella typhi, Shigella spp., Vibrio cholerae and Yersinia enterocolitica) with that of rosoxacin, flumequin, nifuroxazide, erythromycin, chloramphenicol, ampicillin, cefotaxime, tetracycline, amikacin, netilmicin, sulfamethoxazole, trimethoprim and co-trimoxazole. Pefloxacin, enoxacin and ciprofloxacin were always among the most active compounds. Furthermore, resistant strains or strains with elevated MIC values were not found. The MIC90 value for these three compounds was less than or equal to 0.25 mg/l, except for C. jejuni where it was 0.3 mg/l and 1.4 mg/l for pefloxacin and enoxacin, respectively.

Antibacterial activity of enoxacin: comparison with aminoglycosides, beta-lactams and other antimicrobial agents.

The activity of enoxacin, a new quinolone carboxylic acid, was evaluated against 3014 clinical isolates of Enterobacteriaceae, Pseudomonas and other non-fermenters and Staphylococcus aureus. Comparison was made with gentamicin, tobramycin, amikacin, netilmicin, ampicillin, piperacillin, carbenicillin, ticarcillin, ticarcillin plus clavulanic acid, trimethoprim, cotrimoxazole and erythromycin. In general enoxacin was the most active compound and resistance was only rarely encountered.

Susceptibility of Gardnerella vaginalis to thiamphenicol: clinical experience with nonspecific vaginitis.

We compared the in-vitro activity of thiamphenicol against 100 strains of Gardnerella vaginalis with the activity of 11 other antimicrobial agents. The MICs for thiamphenicol ranged from 0.39 micrograms/ml to 6.25 micrograms/ml. The concentration at which 50% of strains were inhibited (MIC50) was 1.96 micrograms/ml, and the concentration at which 90% of strains were inhibited (MIC90) was 3.93 micrograms/ml. All strains were very susceptible to erythromycin, chloramphenicol, beta-lactam antibiotics, and clindamycin. Tetracycline and metronidazole were only moderately active. In an attempt to cure G. vaginalis-associated vaginitis with a single-dose treatment, we administered 2.25 g of thiamphenicol to 20 volunteers; 17 were clinically and bacteriologically cured. In two cases we observed that G. vaginalis was not eliminated immediately (i.e., at the first follow-up visit), but we saw a progressive disappearance of the strain without further treatment. In one case the treatment seemed to have failed but reinfection could not be ruled out. The results show that a single dose of thiamphenicol can cure G. vaginalis-associated vaginitis.

[Cat-scratch disease]. / Maladie des griffes de chat.

A case of cat-scratch syndrome is described. The dermatological features and skin reactions reported in this illness (erythema nodosum, erythema multiforma) as well as the diagnostical criteria are reviewed. The hypothetical nature of the etiologic agent of this syndrome is discussed.