Increased Prevalence and Resistance of Important Pathogens Recovered from Respiratory Specimens of Cystic Fibrosis Patients During a Decade

Pediatr Infect Dis J. 2015 Jul;34(7):700-5. doi: 10.1097/INF.0000000000000714.


Background: The study objective was to identify changes of prevalence and resistance of important pathogens in specimens of cystic fibrosis (CF) patients within a decade.

Methods: Samples of 94 patients, who attended 2 CF centers from 2001 to 2011 were retrospectively analyzed.

Results: Staphylococcus aureus was the most prevalent organism (74.5% in 2011) with an increase of methicillin-resistant S. aureus in patients (0% vs. 9.6%, n = 9). Resistance of S. aureus to gentamicin decreased (41.8% vs. 21%; P < 0.001), whereas resistance to rifampicin and trimethoprim/sulfamethoxazole (P < 0.05) increased significantly with a trend to increased resistance to clindamycin and erythromycin (P = 0.063). Methicillin-resistant S. aureus isolates belonged to 6 spa types (t003, t008, t011, t034, t045, t548). There was a significant increase of Pseudomonas aeruginosa prevalence (63.8% in 2011 vs. 46.8% in 2001, P = 0.019). Resistance of P. aeruginosa increased significantly to imipenem, gentamicin, amikacin, tobramycin, ciprofloxacin and fosfomycin, whereas resistance to piperacillin-tazobactam, meropenem and aztreonam decreased. Significantly fewer Stenotrophomonas maltophilia isolates were susceptible to all the analyzed antibiotics (trimethoprim/sulfamethoxazole, ciprofloxacin and colistin) in 2011 compared with 2001 (13.5% vs. 42.1%; P = 0.023), whereas the resistance to colistin increased significantly (11.1% vs. 62.2%; P < 0.001). Burkholderia cepacia complex and nontuberculous mycobacteria were not detected in 2001 but in 2011 in 7.4% (n = 9) and 7.4% (n = 9) of patients, respectively. B. cepacia complex isolates belonged to 8 multilocus sequence types.

Conclusions: Our retrospective analysis revealed an increase of important CF-related pathogens, the emergence of new pathogens and a substantial increase of multidrug-resistant CF-specific isolates. Our findings are of importance to clinicians for the alertness of local epidemiology, which may be useful for prevention and treatment strategies.

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Bacteria / classification
  • Bacteria / drug effects*
  • Bacteria / isolation & purification
  • Bacterial Infections / epidemiology*
  • Bacterial Infections / microbiology*
  • Child
  • Child, Preschool
  • Cystic Fibrosis / complications*
  • Drug Resistance, Bacterial*
  • Female
  • Humans
  • Infant
  • Male
  • Middle Aged
  • Prevalence
  • Respiratory Tract Infections / epidemiology*
  • Respiratory Tract Infections / microbiology*
  • Retrospective Studies
  • Young Adult