The characteristics of the minimum inhibitory concentration of antibiotics on pulmonary infections in patients with cystic fibrosis S. Sciuca 1,2, L. Balanetchi 1 1 State Medical and Pharmaceutical University NicolaeTestemitanu, 2 Mother and Child Institute, Cystic Fibrosis Center Chisinau, Republic of Moldova, ACTUALITY Optimising antibiotic selection for treatment of exacerbations is currently a difficult task for clinicians. We know that susceptibility testing may be helpful, and that around 75% of pulmonary exacerbations result in a return to baseline lung function and/or rapid relapse. There is a large unmet need in terms of laboratory tests that will reliably predict clinical response in exacerbation therapy. To test which antibiotics were most effective at inhibiting the growth of Ps. aeruginosa in CF patients. To this we carried out a MIC (minimum inhibitory concentration) assays against Pseudomonas aeruginosa strains, Staphylococcus aureus, Stenotrophomonas maltophilia and Burkholderia cepacia. METHODS This study presents an analysis of microbiological examination of sputum in CF patients. Microbiological research was performed with classical methods and apparatus „Walk-Away-96" ("Siemens", Germany), which determines the minimum inhibitory concentration (MIC) of antibiotics. The number of CF patient oversight at the Cystic Fibrosis Centre in the Republic of Moldova is increased from 43 in 2009 to 62 patients in 2014 RESULTS The frequency of lung infections with Ps. aeruginosa in CF patients from Republic of Moldova during the last 6 years is 45-62%, in 50-57% are detected S. aureus and in 3 cases – pulmonary infection with Stenotrophomonas maltophilia, MRSA - 3 cases and Burkholderia cepacia – in 1 adult patients with CF. Microbiological research found that 80% of Ps.aeruginosa strains are sensitive to Tobramycin (MIC≤4), 61% to Amikacin (MIC≤16), 50% to Ofloxacin, 70% to Piperacillin/ Tazobactam, in 76% to Ceftazidime (MIC≤8), 84% to Imipenemes group, 87,5% to Sodium Colistimate, 68% to Ciprofloxacine, and in 1/4 cases Ps.aeruginosa was resistant to this antibiotic (MIC> 4). S. aureus lung infection present standard antibiotic susceptibility and only in 3 patients was confirmed multidrug-resistant MRSA. Stenotrophomonas maltophilia strains identified in CF patients were multidrug-resistant, at one CF child - sensitive to ceftazidime and amikacin, and the last one sensitive to levofloxacine. B.cepacia have a good sensitivity to these antibiotics. The range of microorganisms causing lung infections in CF patients is quite distinct, where prevails Pseudomonas aeruginosa, Staphylococcus aureus, and after this bacteria are Haemophylus influenzae, Stenotrophomonas maltophilia, MRSA, Burkholderia cepacia and others. This study showed that the sodium colistimate, imipenems and tobramycine was the most effective antibiotics at inhibiting the growth of Ps. aeruginosa strains; for S. aureus most effective was beta-lactam antibiotics (penicillin and cephalosporin) and 3 cases was with multidrug-resistant MRSA. AIM CONCLUSIONS REFERENCES 1.UK Cystic Fibrosis Registry. Annual data report Aaron SD, Vandemheen KL, Ferris W, et al. Combination antibiotic susceptibility testing to treat exacerbations of cystic fibrosis associated with multiresistent bacteria: a randomized, double-blind, controlled clinical trial. Lancet Weaver T, Green MR, Nicholson K, et al. Prognosis in Cystic fibrosis treated with continuous flucloxacillin from the neonatal period. Arch Dis Child Smyth AR, Walters S. Prophylactic anti-staphylococcal antibiotics for cystic fibrosis. Cochrane Database Syst Rev Hansen CR, Pressler T, Hoiby N. Early aggressive eradication therapy for intermittent Pseudomonas aeruginosa airway colonization in cystic fibrosis patients: 15 years experience. J Cyst Fibros Cystic Fibrosis Foundation. Patient registry 2011 annual report. Bethesda, CFF Doring G, Flume P, Heijerman H, et al. Treatment of lung infection in patients with cystic fibrosis: current and future strategies. J Cyst Fibros Ratjen F, Munch A, Kho P, et al. Treatment of early Pseudomonas aeruginosa infections in patients with cystic fibrosis: the ELITE trial. Thorax 2010.