In recent years, an increase in the number of patients with chronic infection with nonfermenting gram-negative bacteria (NFGNB) in adult patients with cystic fibrosis (CF) has increased. The genotype and phenotype characteristics, NFGNB structure, changes in sensitivity and the development of antibiotic resistance in adult patients have not been adequately studied.Aim. To determine the impact of genotype severity and Achromobacter xylosoxidans sensitivity to carbapenems on the functional and nutritional status of adult cystic fibrosis patients over a period 2016 – 2021.Materials. Retrospective analysis of genotypic and microbiological data from 54 adult CF patients and their effects on FEV1 and BMI over a period 2016 – 2021. Sputum cultures were confirmed by MALDI-TOF mass spectrometer. Depending on the severity of the mutation, the patients were divided into 2 groups: group 1 (“severe” genotype) – patients who had 2 mutations of class I – III; group 2 (“soft” genotype) – at least 1 class IV – VI mutation.Results. The group of patients with “mild” mutations had a higher BMI (kg / m2) than the group with severe mutations for a longer period of follow-up from 2018 – 2021 than in the group with severe mutations: BMI (2016) – 21.14 ± 3.55 / 19.28 ± 3.13 (p = 0.163); BMI (2017) – 21.27 ± 3.43 / 18.31 ± 2.05 (p = 0.123); BMI (2018) – 21.17 ± 4.00 / 18.80 ± 2.12 (p = 0.025); BMI (2019) – 21.01 ± 4.20 / 18.55 ± 2.53 (p = 0.049); BMI (2020) – 20.94 ± 4.12 / 18.41 ± 2.15 (p = 0.050). Age at diagnosis was 20.36 ± 2.18 years for “mild” genotypes and was higher (p = 0.042) than for “severe” genotypes (6.27 ± 1.53 years). All 7 patients who died (100%) were in the “severe” genotype group (23.3%). Functional status assessment showed no differences in FEV1 over 6 years between the “severe” and “mild” genotype groups: FEV1 (2016) – p = 0.51; FEV1 (2017) – p = 0.39; FEV1 (2018) – p = 0.51; FEV1 (2019) – p = 0.35; FEV1 (2020) – p = 0.48. Nonfermenting Gram-negative bacteria accounted for 49.9% of the isolated microorganisms. The group of carbapenem-resistant Achromobacter xylosoxidans lost the FEV1 level faster every year for 6 years (p < 0.05) compared to the group of the sensitive variant.Conclusion. In general, patients with the “mild” genotype have higher nutritional status and do not differ from patients with the “severe” genotype in terms of FEV1. The survival rate of patients with the “mild” genotype patients survival rate is higher, despite the later diagnosis and start of treatment. Development of carbаpenem resistance in Achromobacter xylosoxidans is associated with an unfavorable prognosis of the functional status decline.

The problem of timely diagnosis and proper management of patients with cystic fibrosis is crucial not only in our country, but throughout the world. Experts of the Union of Pediatricians of Russia have considered various issues of etiology, pathogenesis, epidemiology, diagnosis, and treatment of this genetic disease in a modern light. Particular attention was paid to screening methods for early diagnosis of cystic fibrosis. The principles of complex therapy were justified, including rational use of antibacterial and mucolytic drugs and enzyme replacement therapy that significantly determine the disease prognosis.

An analysis of the current treatment protocol for lower respiratory tract infection using inhaled antibiotics is presented. Information about the pathophysiology and features of pathogens of bronchopulmonary infection in patients suffering from cystic fibrosis, nosocomial pneumonia, chronic obstructive pulmonary disease, and bronchiectasis of various etiologies is considered. The advantages and applications of inhaled antibiotics in the treatment of this category of patients are discussed. It has been established that acute and chronic infectious diseases of the lower respiratory tract are often the cause of severe human diseases and one of the leading causes of infectious mortality worldwide. Early initiation of adequate antibiotic therapy, especially in patients with a tendency to develop chronic inflammation, improves disease prognosis. However, mortality and the resistance of pathogens in this category of patients remain high. Traditional oral or parenteral antibiotic therapy does not achieve bactericidal concentrations in the lungs. Increasing dosages and combining antibiotics increases the likelihood of toxicity, superinfection, and resistance and causes undesirable side effects. Inhalation of antibiotics allows the delivery of higher concentrations directly to the lesion, thereby affecting the causative agents of the infectious process effectively while minimizing potential systemic toxicity. The large surface area of the alveoli and the thin epithelial layer provide a favorable environment for the deposition of inhaled drugs. Acute and chronic gram-negative bronchial infection caused by certain types of opportunistic microorganisms causes chronic inflammation, which leads to airway remodeling, damage to local defense mechanisms, further persistence of respiratory pathogens, and the formation of antibiotic resistance. In these cases, the use of inhaled forms of antibiotics has significant advantages in terms of effectiveness, stabilizing lung function and reducing the frequency of hospitalization, which improves quality of life and the need for systemic antibiotic therapy, reduces the risk of side effects, and reduces the cost of treatment. The results of the work can be useful for both therapists and pulmonologists.

Accepted, basic therapy of cystic fibrosis (CF), until recently, was symptomatic and aimed at slowing down pathological processes, mainly from the respiratory system and gastrointestinal tract, caused by a defect in the CFTR gene. New strategic opportunities have emerged since 2012 and are aimed at correcting a defect in a gene or its product. A mutation in the cystic fibrosis gene disrupts the function of the cystic fibrosis transmembrane conductance regulator protein (CFTR or CFTR in English transcription), which is located on the surface of the apical membrane of epithelial cells and functions as a chloride channel. The basic achievement for the new CF therapy was the discovery of small molecules that restore the processes of synthesis, transport to the membrane, or the  functioning of  the defective CFTR protein. The effectiveness of  drugs that restore CFTR function is related to the ability of the molecules to deliver an adequate amount of the CFTR protein to the surface of the epithelial cell and/or improve its functional activity. Among them, correctors and potentiators for pharmacological modulation of ion transport are distinguished in clinical practice. Correctors are medicinal substances that allow the mutant CFTR protein to pass through the system of intracellular quality control and take the correct location on the apical membrane (with class II mutations). The action of potentiators is aimed at restoring (activating) the function of the ion channel formed by the mutant CFTR protein (class III–IV mutations). The purpose of this article is to analyze the literature sources, the results of clinical trials on the use of CFTR modulators, including combinations of a potentiator and a corrector. Their effectiveness and safety were evaluated. Literature sources (20) are used and own clinical observation is given. A positive assessment of the action of the modulator, the combination of a potentiator and a corrector, its safety and good tolerability is given. In conclusion, the place and indications for prescribing drugs of this class, the number of patients in the Russian Federation in need of such treatment are determined.