P148 Mixed bacterial-viral lung infections in patients with cystic fibrosis (CF) during an exacerbation

Chronic lung infection in patients with cystic fibrosis in more than 70% of cases is mixed. About 40% of CF patients during exacerbations of a chronic lung infection require hospital treatment. CF, like other congenital pathologies of the respiratory system, is a risk factor for a more unfavourable course of viral infections of the respiratory tract. Analysis the prevalence of mixed bacterial-viral infections in children and adults with cystic fibrosis during an exacerbation of a chronic lung infection. Samples of biological material from 109 children and 60 adults with CF were studied from 2018 to 2022. Identification of microorganisms and viruses was carried out using bacteriological, molecular-genetic methods, MALDI-TOF-MS. Associations of microorganisms - causative agents of chronic lung infection were detected in CF patients during an exacerbation: S.aureus, P. aeruginosa, Candida spp., S. maltophilia, Achromobacter spp., Burkholderia cepacia complex, K.pneumoniae, A.baumanii. In 67.5% of cases in children, associations of microorganisms included S.aureus, in 37.8% - P.aeruginosa, and the association of these two microorganisms was the most common among children with CF (24.3%). The dominant association in adults with CF is also the combination of S.aureus and P.aeruginosa (36%). However, in adults the detection frequency of both microorganisms in all identified associations is the same - 76%. Real-time PCR showed the presence of rhinovirus RNA in 10% of samples obtained from children during an exacerbation, and in 12.9% from adults with CF. Studies have shown that the cause of an exacerbation can be both a mixed bacterial and a viral-bacterial infection. Identification of markers of viral lung infections during exacerbations in patients with cystic fibrosis gives grounds to expand the laboratory diagnostic algorithm to determine the etiology of exacerbations and, as a result, improve the system of preventive measures.