Changes in antimicrobial resistance in clinical pediatric isolates of Haemophilus influenzae, Streptococcus pneumoniae, and Moraxella catarrhalis in Middle Ural area

Abstract

Objective. To reveal the prevalence of antimicrobial resistance of H. influenzae, S. pneumoniae, and M. catarrhalis clinical pediatric isolates in Yekaterinburg and Sverdlovsk region during 2013-2015. Materials and Methods. In total 231 H. influenzae, 289 S. pneumoniae, and 266 M. catarrhalis isolates were included in the study. Antimicrobial susceptibility testing was performed partially by disc-diffusion method and partially by automated method, depending on the local practice; β-lacamase production was detected by the nitrocefin disc test. Results. Among H. influenzae isolates 211 (91.4%) were β-lactamase-negative and susceptible to ampicillin, 13 (5.6%) β-lactamase-positive and resistant to ampicillin; 7 (3%) – β-lactamase-negative and resistant to ampicillin. Among S. pneumoniae strains 33.2% were non-susceptible to penicillin; susceptibility to cefotaxime and ceftriaxone was 89.2% and 93.5% respectively; 27.3% of strains were resistant to erythromycin, 20.8% – to clindamycin. β-Lactamase production was detected in 91.7% of M. catarrhalis isolates. Conclusions. H. influenzae remain very high susceptibility level to β-lactams. Increase of the prevalence of S. pneumoniae non-susceptibility to penicillin and other β-lactams require further monitoring. High rate of β-lactamase production by M. catarrhalis isolates was noted.

Keywords

• h. influenzae
• s. pneumoniae
• m. catarrhalis
• antimicrobial resistance
• respiratory infections
• children