[Sensitivity to antibiotics in coagulase-negative staphylococci isolated from patients with central venous catheters]

We examined 25 coagulase-negative staphylococci isolated from children, of whom 17 with leukaemia and 8 with terminal renal failure. Strain identification performed by api Staph system revealed the presence of S. epidermidis in 21 children, S. hominis in 3 patients and S. haemolyticus in 1 patient. By diffusion method we examined the activity of penicillin, methicillin, cephalexin, cephtriaxon, lincomycin, erythromycin, vancomycin, co-trimoxasol, gentamicin, amikacin, chloramphenicol, rifampicin and fusidic acid. MICs of seven antibiotics were obtained by agar dilution method. MIC50 and MIC90 were as follows: /ml Methicillin 3.13 mg/ml and 50 mg/ml, lincomycin 100 mg/ml and 100 mg/ml, gentamicin 25 mg/ml and 100 mg/ml, chloramphenicol 6.25 mg/ml and 50 mg/ml, amikacin 1.56 mg/ml and 100 mg/ml, rifampicin 0.09 mg/ml and 12.5 mg/ml, fusidic acid 6.25 mg/ml and 12.5 mg/ml, vancomycin 1.56 mg/ml and 3.13 mg/ml. These data show that the examined strains are highly resistant to numerous antibiotics. Thirty six percent of all strains were resistant to methicillin, 88% to lincomycin, 60% to gentamicin, 52% to chloramphenicol, 24% to amikacin, 52% to rifampicin and 56% to fuscidic acid. All the examined strains were sensitive to vancomycin.