[Staphylococci as uropathogens-frequency of isolation in hospitalized patients and sensitivity to antimicrobial agents]. / Les staphylocoques comme uropathogènes-fréquence d'isolement chez des malades hospitalisés et sensibilité envers les substances antibactériennes.

For a period of 24 months (1997-1999) were isolated 266 clinically significant staphylococcal strains, S. aureus, 36 (13.5%) and 230 (86.5%) coagulase negative staphylococci (CNS) from urines of hospitalised patients (over 14 years) with UTI. The most frequently isolated strains from CNS was S. haemolyicus, 110 (47.8) strains, followed by S. saprophyticus 47 (20.4%) strains and S. epidermidis 18 (7.8%). The susceptibility of the isolates to 13 antimicrobial agents was determined by agar dilution method (NCCLS). From the isolated 36 strains S. aureus, 24 were sensitive and 12 were resistant to methicillin. From 230 CNS, 105 strains showed sensitivity and 125 strains resistance to methicillin. All staphylococci were sensitive to vancomycin and most of them (over 95%) to amikacin and rifampin. It was established a considerable difference between the sensitivity of methicillin-sensitive and methicillin-resistant staphylococci. The established resistance accompanied with high rate percentage methicillin resistance requires careful consideration to antimicrobial therapy of staphylococcal urinary tract infections (UTI).

In vitro investigation of the susceptibility of Acinetobacter baumannii strains isolated from clinical specimens to ampicillin/sulbactam alone and in combination with amikacin.

The sensitivity of 52 strains of Acinetobacter baumannii was determined to 13 antimicrobial drugs. All strains tested were multiresistant. Compared with MICs of amikacin and ampicillin/sulbactam alone, there was a significant decrease in MICs for both drugs when the combination was used. The results of the in vitro study of this combination showed a synergistic or partial synergistic effect in 98% of the strains.

[Enterococci as uropathogens. Frequency of isolation and sensitivity to antibacterial agents]. / Les entérocoques comme uropathogènes. Fréquence d'isolement et sensibilité envers les substances antibactériennes.

221 clinically significant enterococcal strains (191: E. faecalis, 27: E. faecium, 3 others) were isolated from the urine of patients hospitalised with UTI over an 18-month period (1995-1996). The susceptibility of the isolates to 8 antimicrobial agents was determined by agar dilution method (NCCLS). All enterococci were sensitive to vancomycin and most of them (over 92%) to penicillin and ampicillin. Only 3.14% of E. faecalis and 3.70% of E. faecium were resistant to ciprofloxacin. A relatively high incidence of resistance of enterococci to aminoglycosides was observed: 46.07% and 51.85% to streptomycin, 42.41% and 44.44% to gentamicin, 70.68% and 77.78% to amikacin for E. faecalis and E. faecium, respectively. Among the resistant to penicillin and amino glycosides enterococci of the two species was found a great percent "high level" resistance. There were no beta-lactamase producers among our strains. The established multiresistance accompanied by "high level" resistance requires careful consideration of antimicrobial therapy of enterococcal UTI.

Typing of Staphylococcus aureus isolated from nasal carriers.

Eighteen Staphylococcus aureus strains (9 pairs) were isolated from 9 apparently healthy persons (including 5 persons from medical staff) regarded as persistent nasal carriers in a 5-7-day or 3-5-month period, respectively. The 18 S. aureus strains were characterized phenotypically and by genotypic methods. Biochemical properties determined with a commercial identification system, production of haemolysins as well as most of the antibiotic resistance date revealed an identity between both strains of each pair. This putative identity was confirmed for most of the paired strains by phage typing and plasmid profiling for all 9 pairs by determination of the number of repeats in the X region of the spa gene and by macrorestriction analysis of the chromosomal DNA of the isolates. The present results indicate that a single clone of S. aureus might colonize continuously persistent nasal carriers over a 5-7 day period, even for a period of 3-5 months.