Introduction: Acute sinusitis is a significant proportion of otolaryngological (ENT) children diseases of all ages. A significant proportion of sinusitis (40%) are bacterial and requires antibiotic therapy. The choice of antibiotic may be influenced by the presence of pathogenic microflora of adjacent organs and its sensitivity.

Aim: To determine the species composition and sensitivity to antibiotics of the nasopharyngeal microflora of children with acute sinusitis. 

Materials and methods: Altogether 208 children with acute sinusitis from the ENT department of Sumy Regional Children’s Hospital at period 2020-2021 were enrolled in the study. X-ray examination was used for the definitive diagnosis. The clinical material (swabs from the nasopharynx) of sick children was amenable to microbiological research. The antibiotic sensitivity of the isolated microorganisms to the 6 most common antibiotics in ENT practice was established using the disco-diffusion method. Antibiotic sensitivity was studied using the disco-diffusion method. Clinical and statistical research methods were also used in the work. 

Results: Оf the total number of children with acute sinusitis in 40 children, no pathogenic microflora was found in nasopharyngeal swabs. Pathogenic microflora was detected in 168 other patients (80.8%): S. aureus in 86 children (41.3%),  S. haemolyticus – 80 (38.5%), E. сoli – 2 (1.0%). The susceptibility of bacteria of the genus Staphylococcus decreased in the following sequence: benzylpenicillin (20.1%) → oxacillin (30.2%) → vancomycin (44.6%) → gentamicin and lincomycin (78.1%) → tobramycin (95.4%).

Conclusions: Pathogenic microflora was detected in nasopharyngeal swabs in 80.8% of children with acute sinusitis. The dominant representative of the pathogenic microflora are bacteria of the genus Staphylococcus. A significant proportion of these bacteria was resistant to a number of antibiotics: benzylpenicillin (20.1%), oxacillin (30.2%), vancomycin (44.6%). In the treatment of patients with acute sinusitis, it is necessary to take into account the degree of contamination of the nasopharynx with pathogenic microflora and the degree of its sensitivity to appropriate antibiotics.