Bacterial lung infections in cystic fibrosis patients: an update

Cystic fibrosis (CF), the most common lethal genetic disorder in Caucasians, affects over 60,000 patients worldwide. Its incidence is 1:2500 of live births.1–3 Advances in CF care have been associated with impressive increases in survival during the last 30 years. The mean life expectancy for patients now diagnosed by newborn screening approaches 40 years.1,2 This striking result is mainly because of better treatment of bacterial lung infections, the main cause of pulmonary deterioration. A relatively limited number of bacteria are involved in lung infections and the prevalence of different pathogens varies according to the patient’s age,1 being usually represented by Staphylococcus aureus in young children and by Pseudomonas aeruginosa (Pa) thereafter. Several emerging pathogens have been described as responsible for severe lung infections, including Achromobacter xylosoxidans, Stenotrophomonas maltophilia, Ralstonia and Pandoraea species, methicillin-resistant S. aureus (MRSA) and nontuberculous mycobacteria (NTM). With aging, recurrent episodes of pulmonary exacerbation cause lung function decline. Because of intensive antibiotic pressure, increasing rates of multidrug-resistant (MDR) bacteria are isolated over time and now represent a major concern. In the absence of adequate isolation measures, bacterial outbreaks have been reported. Burkholderia cepacia complex outbreaks are associated with poor outcomes and sustained mortality rates