Investigation of respiratory pathogens in patients with cystic fibrosis

Cystic fibrosis (CF) is a genetic disorder most commonly seen in Caucasians, inherited in an autosomal recessive manner. The leading cause of mortality in CF patients are frequently lung infections. This genetic disorder leads to the colonization of the mucosa with various microorganisms, initially in the upper respiratory tract and later in the lower respiratory tract. This study was conducted with 100 patient samples, 19 of which showed no bacterial growth or only flora bacteria. Among these CF patients, 54 were female (54%) and 46 were male (46%), with a male-to-female ratio of 1.17. This study focused on bacterial respiratory pathogens and their antibiotic susceptibility testing. Of the samples, 68 were sputum samples, and 32 were transtracheal aspiration samples. Bacterial cultures yielded 49.38% Staphylococcus aureus, 32.09% Pseudomonas aeruginosa, 16.04% Moraxella, 6.17% Streptococcus pneumoniae, 1.23% Burkholderia cepacia, 1.23% Escherichia coli, 7.40% Haemophilus influenzae, 4.93% Corynebacterium, and 1.23% Klebsiella pneumoniae. S. aureus and P. aeruginosa were the most frequently isolated pathogens. Among the S. aureus isolates, 13 were found to be MRSA. The highest resistance was observed against erythromycin (50%). For P. aeruginosa isolates, meropenem was found to be the most effective antibiotic. Of the P. aeruginosa isolates, 10 were found to have a mucoid phenotype. The association between antibiotics and two age groups of S. aureus and P. aeruginosa was evaluated using the Pearson Chi-square test. In this test, a p-value below 0.05 indicates statistical significance. For P. aeruginosa, p-values were above 0.05 in all data groups, indicating no significant relationship. However, for S. aureus, significant results were obtained with erythromycin and ciprofloxacin. These patients are typically infected with multidrug-resistant or pan-resistant P. aeruginosa strains. Due to these issues, there has been an increasing trend toward alternative treatment methods, such as phage therapy. In this study, two P. aeruginosa isolates from CF patients were subjected to phage isolation. Genomic analysis of the isolated phages was performed, and phylogenetic trees and genomic maps of the phages were generated.