Streptococcus pneumoniae is the most important respiratory tract pathogen in otitis, sinusitis, bronchitis, and community-acquired pneumonia.
Material and methods: A total of 155 patient isolates of S. pneumoniae were collected between February 2003 and December 2009 from the Iaşi "Sf. Parascheva" Infectious Diseases Hospital. Susceptibility to antibiotics was assessed by disk diffusion method (CLSI 2003-2008); minimum inhibitory concentrations (MIC) to penicillin and cefotaxime were determined by broth dilution method or E-test method.
Results: Of these isolates, 32.6% were penicillin non-susceptible (MIC > or = 0.12 microg/mL for nonmeningeal isolates before 2008 and all meningeal isolates and MIC > or =2 microg/mL for nonmeningeal isolates after 2008). The percentage of penicillin resistance increased from 0% to a maximum of 50% in 2008. Resistance rates (intermediate and resistant strains) among non-beta-lactam agents were as follows: macrolides, 30.9%; clindamycin, 9%; tetracycline, 34.3%; chloramphenicol, 2.1%; and trimethoprim-sulfamethoxazole, 57.5%. No resistance to vancomycin, linezolid and quinupristin-dalfopristin was observed. Resistance to non-beta-lactam antibiotics was higher among penicillin-resistant strains than penicillin-susceptible strains. Overall, antimicrobial resistance was higher among isolates from respiratory tract comparing with isolates from cerebrospinal fluid and blood.
Conclusions: Resistance rates with S. pneumoniae have markedly increased in Romania during the last years. Pneumococcal isolates from laşi, Romania are often resistant to beta-lactams and available non-beta-lactam agents, especially if penicillin non-susceptible.