Use of Aerosolized Antibiotics in Patients With Cystic Fibrosis: Microbiological indications
4. At present, there are no microbiological indications to discontinue treatment with aerosolized antibiotics. The emergence of resistant P aeruginosa or acquisition of intrinsically antibiotic-resistant organisms such as B cepacia and S maltophilia does not preclude the continued use of nebulized agents intermittently (consensus grade II-2).
Comment: Several previously published studies have shown transient emergence of resistant P aeruginosa during therapy with aerosolized antibiotics that reverted to a susceptible phenotype with discontinuation of treatment with the nebulized agent. This supports the practice of alternate on and off months of therapy and may suggest that more prolonged suspension of aerosol treatment could be useful. Reading here
5. Processing of CF respiratory tract specimens should be performed according to the recommendations of the previously published CF consensus document, Microbiology and Infectious Disease in CF (CF Foundation Clinical Practice Guidelines, Appendix VIII) and CF Center Directors should meet with their laboratory directors to discuss their concerns (consensus grade III).
Comment: Baseline susceptibility testing should be considered prior to initiation of treatment with aerosolized antibiotics. When clinically indicated, determining the susceptibility of strains at the end of the “off cycle” might aid in the detection of reemergence of susceptible strains. It is strongly recommended that susceptibility testing be performed if there is a significant deterioration in pulmonary function or clinical status.
6. Many institutions have software systems in place to detect trends in antibiotic resistance patterns for specific pathogens and specific patient populations. Consideration to perform such monitoring for CF patients and for P aeruginosa should be given at individual centers (consensus grade III).
7. Reference laboratories are currently available to identify putative B cepacia strains, to assess patient-to-patient spread, to perform synergy studies, and to examine strains with high level MICs. Clinicians are encouraged to use these resources. Quantitative assessment of sputum flora is routinely available only in research settings (consensus grade III).
8. Each center should develop a formal policy for aerosolized antibiotic use in the home, clinic, and inpatient facility. Such a policy should address barrier techniques, filters, exhaust, environmental contamination, disposal of unused product, and cleaning of nebulizers (consensus grade III).