[CF Lung Disease - a German S3 Guideline: Module 2: Diagnostics and Treatment in Chronic Infection with Pseudomonas aeruginosa]. / S3-Leitlinie: Lungenerkrankung bei Mukoviszidose ­ Modul 2: Diagnostik und Therapie bei der chronischen Infektion mit Pseudomonas aeruginosa.

Cystic Fibrosis (CF) is the most common autosomal-recessive genetic disease affecting approximately 8000 people in Germany. The disease is caused by mutations in the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) gene leading to dysfunction of CFTR, a transmembrane chloride channel. This defect causes insufficient hydration of the epithelial lining fluid which leads to chronic inflammation of the airways. Recurrent infections of the airways as well as pulmonary exacerbations aggravate chronic inflammation, lead to pulmonary fibrosis and tissue destruction up to global respiratory insufficiency, which is responsible for the mortality in over 90 % of patients. The main aim of pulmonary treatment in CF is to reduce pulmonary inflammation and chronic infection. Pseudomonas aeruginosa (Pa) is the most relevant pathogen in the course of CF lung disease. Colonization and chronic infection are leading to additional loss of pulmonary function. There are many possibilities to treat Pa-infection. This is a S3-clinical guideline which implements a definition for chronic Pa-infection and demonstrates evidence-based diagnostic methods and medical treatment for Pa-infection in order to give guidance for individual treatment options.

Stenotrophomonas maltophilia in cystic fibrosis: improved detection by the use of selective agar and evaluation of antimicrobial resistance.

BACKGROUND: We implemented a selective medium for improved detection of Stenotrophomonas maltophilia in sputum samples from CF patients. We also performed antimicrobial susceptibility testing with eight antibiotics. METHODS: A total of 623 consecutive sputum samples from 165 CF patients in a German CF center were cultured onto conventional media and onto Steno medium agar (SMA). All isolates confirmed as S. maltophilia by biochemical and molecular methods were subjected to antimicrobial susceptibility testing. The following agents were tested by Etest: ceftazidime, levofloxacin, moxifloxacin, tigecycline, trimethoprim-sulfamethoxazole, fosfomycin, colistin, and ticarcillin-clavulanate acid. RESULTS: Conventional media supported the growth of S. maltophilia in 7.1% of samples, whereas SMA supported its growth in 11.6%, increasing the detection rate to 64%. Trimethoprim-sulfamethoxazole and tigecycline exhibited the highest in vitro activity, whereas ceftazidime, colistin, and ticarcillin-clavulanate acid exhibited higher resistance rates. CONCLUSIONS: SMA is a promising medium allowing improved isolation of S. maltophilia from sputum samples from CF patients. Trimethoprim-sulfamethoxazole and tigecycline demonstrated excellent inhibitory effects against S. maltophilia, which may suggest a potential clinical effect.