Minimum inhibitory concentrations of antibacterial drugs for Staphylococcus epidermidis strains isolated from the contents of the tracheobronchial tree of newborn children

Introduction. Over the past decades, outstanding progress has been made in caring for extremely premature infants and newborns with severe pathologies. Management of this vulnerable category of patients is associated with the continued risk of developing infectious pathology. In the structure of nosological forms, neonatal sepsis caused by coagulase-negative staphylococci occupies one of the leading positions. There is an increase in the number of antibiotic-resistant strains, including among Staphylococcus epidermidis, a typical representative of the normal microbiocenosis of human skin, so colonization of a premature newborn child who is at the stationary stage of nursing with it is a typical process.

Objective. To study changes in the minimum inhibitory concentration of antibacterial drugs for Staphylococcus epidermidis strains isolated from the contents of the tracheobronchial tree of newborn children at the nursing stage in a hospital setting.

Material and methods. To assess the statistical significance of the results obtained, the Chisquare test with Yates correction and the Mann-Whitney U test were used. Research results. All strains tested were resistant to cefoxitin. This, in turn, determines resistance to protected penicillins, amoxicillin clavulanate, ampicillin, sulbactam, and cephalosporins of I-IV generations. 44.4% and 87.5% of Staphylococcus epidermidis strains resistant to gentamicin were registered in 2022 and 87.5% in 2024.When comparing the MIC to gentamicin of Staphylococcus epidermidis isolated from TBD, a significant increase in indicators was established in 2024 compared to 2022 (Mann-Whitney U test is 7.5; p<0.05). The proportion of clindamycin-resistant Staphylococcus epidermidis strains is 44.4% in 2022 and 12.5% in 2024 (p = 0.179). > < 0.05). The proportion of clindamycin-resistant Staphylococcus epidermidis strains is 44.4% in 2022 and 12.5% in 2024 (p = 0.179).

Conclusion. Thus, the analysis of antibiotic resistance of staphylococci isolated during bacteriological examination of the contents of the tracheobronchial tree demonstrates an increase in the MIC of Staphylococcus epidermidis to gentamicin.The high therapeutic potential of vancomycin, a deep reserve antibiotic for the treatment of congenital and hospital-acquired pneumonia in premature newborns, remains high.

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