Objective:

The aim of this study was to determine the susceptibility of the most common bacterial pathogens in respiratory tract infections.

Material and Methods:

Between January 2002 and December 2002 a total of 658 strains were collected from 361 adults and 297 children with community acquired respiratory tract infections from different Austrian regions. A total of 282 Staphylococcus aureus, 150 Streptococcus pyogenes, 120 Haemophilus influenzae and 106 S. pneumoniae were identified according to standard laboratory techniques. Antimicrobial susceptibility testing was performed by broth microdilution method according to NCCLS guidelines. The following antibiotics were tested: erythromycin (ERY), clarithromycin (CLA), azithromycin (AZI), telithromycin (TEL), penicillin (PEN), amoxicillin–clavulanic acid (AUG), ampicillin (AMP), cefotaxime (CTX), cefpodoxime (CPD), ciprofloxacin (CIP), levofloxacin (LEV), moxifloxacin (MXF), gatifloxacin (GAT), tetracyclin (TET), quinupristin–dalfopristin (SYN), linezolid (LNZ), vancomycin (VAN), gentamicin (GEN) and fusidic acid (FUS).

Results:

A 72% (n = 475) of the strains were isolated from upper respiratory tract and 28% (n = 183) from lower respiratory tract. Against S. aureus the most active agents were LNZ (100%), VAN (100%), LEV (99%), MXF (99%), and FUS (99%). PEN, LNZ, MXF, GAT, LEV, CTX and CPD showed the best activity against S. pyogenes (from 100 to 99%). The most active agents against S. pneumoniae were AUG, LNZ, MXF, TEL, CTX (100% susceptible). Among H. influenzae 100% were susceptible among CIP, LEV, MXF, GAT, TEL, CTX and CPD.

Conclusions:

The results demonstrate that the resistance rates of the respiratory tract pathogens among most antibiotics were less than 10%.