P397\u2005Microbiology of gram-positive bloodstream infections in children in minsk

Abstract

The aim of this study was to investigate the role of gram-positive bacteria in the structure of pathogens isolated from blood cultures, to update later approaches to empirical therapy and to compare our data with current trends worldwide. Material and methods In a retrospective study from 2009 to 2017, the etiological structure of identified blood flow infections was studied. The study was conducted in the viral and bacteriological laboratory of the City children’s infectious clinical hospital in Minsk. Only for the period allocated 654 pathogen cultured from blood cultures 515 patients aged from 3 weeks to 18 years old. In patients with clinical signs of systemic infection (chills, tachycardia, hypotension, oliguria, impaired consciousness, behavior, rash, etc.) on the background of fever 38°C and above, blood was taken for microbiological examination. For the analysis of the etiological structure recorded of any pathogen isolated from blood cultures. A blood culture was considered positive when a single isolation of the pathogen. With the simultaneous or sequential release of several microorganisms belonging to different species, all strains were included in the analysis. The repeated selection of identical the causative agent in the statistical analysis of the pathogen fell only once. Hemocultures were isolated using a BacT/alerT 3D hemoculture analyzer using commercial culture media (BacT/alerT SA, BacT/alerT SN, biomérieux, France). Identification of microorganisms was carried out on the automatic microbiological analyzer Vitek 2 Compact (bioMérieux, France). Results According to the results of the study, the proportion of gram-negative bacteria in the structure was 31.7% (n=208), gram-positive bacteria – 61.9% (n=404), fungi – 6.4% (n=42). During the analyzed period, the predominance of gram-positive microorganisms in the structure of bacteremia remains. The structure of gram-positive bacteria (n=404) was dominated by staphylococci (62.1%), with the most frequently isolated coagulase-negative types (n=212; 84.5%). Among all staphylococci (n=25.1), the most frequently isolated cases were S. epidermidis – 63.3%, and S. aureus –15.1%. The spectrum of streptococci (n=66) was as follows: Str. viridans groups (42.4%), Str. pneumonia (27.3%), Str. agalacia (19.7%) and Str. pyogenes (10.6%). Enterococci were isolated in 31 patients (7.7% of cases), with almost the same frequency met Enterococcus faecalis and Enterococcus faecium (41.9% and 38.7%, respectively). During the study period, 7 (1.7%) strains of Corynebacterium spp. were isolated. The data obtained by us fully correspond to modern studies from other countries, according to which the most common pathogens of blood flow infections are coagulase-negative staphylococci (especially epidermal).