Variability of ß-lactamase resistance Pseudomonas aeruginosa genes infecting patients with cystic fibrosis

Variability of&nbsp;β-lactamase resistance <i>Pseudomonas aeruginosa</i> genes infecting patients with cystic fibrosis <b>Background:</b> The emergence of multidrug-resistant&nbsp;<i>Pseudomonas aeruginosa</i> (MDR-PA) is a therapeutic challenge in patients with CF.&nbsp;β-lactamases are the most important mechanism of resistance to&nbsp;β-lactam antibiotics. <b>Aims:</b> To identify the variability of&nbsp;β-lactamase resistance genes of&nbsp;MDR-PA in sputa of CF patients <b>Methods:</b> Two hundred forty -six&nbsp;MDR-PA isolates were collected from lower respiratory samples of patients with pulmonary diseases over the 3-year period. Eighteen(7.32%) sputa samples were from 5 CF patients. The identification and antimicrobial susceptibility of the&nbsp;MDR-PA isolates were performed using BD PhoenixTM and E-test in compliance with CLSI guidelines. Whole-genome sequencing was used for gene identifications. <b>Results:</b> Nine sputum samples were collected from CF patient 1;4 samples from patient 2;2 samples each of patients 3 and 4 and 1 sample from patient 5. The&nbsp;β-lactamase resistant&nbsp;<i>P aeruginosa</i>&nbsp;showed the highest resistance toward cefepime (100%), 55.56% toward each piperacillin-tazobactam and meropenem, and 50% to ceftazidime. β-lactamase genes in&nbsp;MDR-PA were variable within the same CF individual and from patient to patient. All classes of&nbsp;β-lactamase&nbsp;genes were identified (Class A; SHV-11, VEB-9, TEM-87, TEM-116, TEM-126. Class B;VIM-2. Class C;PDC-1, PDC-3, PDC-7, PDC-8. Class D;OXA-10, OXA-50, OXA-114a) with the highest percentage for OXA-50 harbored in 61.11% of isolates <b>Conclusions:</b> Variability of&nbsp;β-lactamase&nbsp;genes in&nbsp;P aeruginosa isolates from CF patients may affect the progression of CF&nbsp;and personal specific antibiotics response to such infection