Detection of Airway Microbiome in Iranian Cystic Fibrosis Patients and the assessment of their bacterial resistance

In people with Cystic Fibrosis (CF), lung infections are the leading cause of mortality. As a result of CF, the human body is predisposed to microbial colonization of its airways due to an inherited systemic metabolic condition. Microorganisms that are harmful to Iranian CF patients are rarely studied. This study was conducted to identify airway microbiota in oropharyngeal swabs of Iranian CF patients and determine their antibiotic resistance. A total of 64 Oropharyngeal swab samples were investigated using PCR and culture methods. Testing for antibiotic susceptibility was then conducted on the confirmed isolates. Finally, the samples were prepared to be sequenced. Among the 80 bacterial isolates in oropharyngeal swabs, 39 (48.75%) were Staphylococcus aureus. This was followed by Pseudomonas aeruginosa 20 (25%), Streptococcus pyogenes 5 (6.25%), Streptococcus group C or G 5 (6.25%), Enterococcus faecalis (45%), and Citrobacter freundii 2 (2.5%). In the study, bacteria resistant to oxacillin (17.78%), trimethoprim-sulfamethoxazole (26.67%), vancomycin (8.89%), and novobiocin (6.67%) were found. In addition to aztreonam, ceftazidime, meropenem, and ciprofloxacin, Gram-negative bacteria were resistant to tobramycin (7%) and ciprofloxacin (18%). The most common isolates in the oropharyngeal CF population are S. aureus and P. aeruginosa. However, the life expectancy of CF patients may be improved by avoiding the colonization of these bacteria.