Zanikanie roznic w lekoopornosci szczepow Staphylococcus aureus izolowanych od pacjentow hospitalizowanych i leczonych ambulatoryjnie

W latach 50-tych dowiedziono, że występujące w szpitalach szczepy Staphylococcus aureus różnią się od szczepów ze środowisk pozaszpi- talnych opornością na co najmniej kilka antybiotyków i przynależnością do I lub III grupy fagowej. W pracy porównano lekooporność i wzory fagowe 771 szczepów gronkowców złocistych wyizolowanych od pacjentów hospitalizowanych lub leczonych ambulatoryjnie. Dyskutowane jest zacieranie się różnic między szczepami S. aureus pochodzącymi z obu środowisk.

There is general opinion that Staphylococcus aureus strains isolated in hospitals are more frequently resistant to antibiotics than community strains, however, the increasing resemblance between hospital and community strains has been recently reported. The aim of the study was to compare the antibiotic resistance and phage-type pattern of S. aureus strains isolated from patients treated either in hospitals or in general practice in northern part of Poland. The study was conducted on 771 S. aureus strains isolated from different specimens. Phage typing was performed according to the method of Blair and Williams. The drug susceptibility was determined by the disc-diffusion method. There were no significant differences in antibiotic resistance or phage-type pattern when hospital and community methicillin-sensitive S. aureus (MSSA) strains were compared. The most MSSA were resistant to penicillin (84,6% and 82,1% respectively) and doxycycline (49,3% and 50,4% respectively) whereas they were rarely resistant to other antibiotics. The predominance of phage group II was found in both hospitals (28,0%) and general practice (29,9%). Phage group III, usually associated with hospitals, occurred in small percentage (12,9% and 9,4% respectively) while to this group predominantly (76,6%) multiresistant methicillin resistant S. aureus (MRSA) isolated in hospitals belonged. These results suggest, that there is only slight difference in antibiotic resistance between hospital and community S. aureus strains. Antibiotic resistance pattern mainly results from frequency of appearance of MRSA, mostly occurring in hospitals.