Resistance spectrum of staphylococci at the Vienna general hospital (July to December 1991)

: This study describes the antibiotic resistance of 1961 staphylococcal strains that were isolated at the University Hospital of Vienna from July to December 1991. Staphylococcus aureus (SA) represented 43.2%; coagulase-negative (CNS) staphylococci 56.8%, three quarters of which were Staphylococcus epidermidis. Excepting netilmicin, the proportion of resistant strains to all antibiotics was higher with CNS than SA. Methicillin resistance (M(r)) was found in 11.8% of SA and 30.3% of CNS. Borderline oxacillin resistance (BOR) was noted in 7.4% of SA and 32.5% of CNS. It is important to note that severe or generalized infections due to M(r) staphylococci should be treated with glycopeptide antibiotics such as vancomycin or teicoplanin from the very beginning, whereas chemotherapy of those with BOR strains may also be carried out with beta lactamase-stable beta lactam antibiotics. Comparing the results of this study with those of the first half of 1991, the respective proportion of M(r) staphylococci was significantly lower than 23.6% for SA and 47.6% for CNS recorded then. As compared with the foregoing period, however, these strains demonstrated increased resistance frequencies to gentamicin (from 81.3 to 90%), amikacin (from 35.4 to 69%), netilmicin (35.4 to 55%), and ciprofloxacin (56.2 to 64%). This is taken as an indication for the epidemic spread of a clone of resistant strains.