[Fluoroquinolones: pharmacology, antibacterial spectrum and indications in pneumology]

Fluoroquinolones are antibiotics that act principally on DNA gyrase. At the moment, resistance to these antibiotics is purely chromosome-mediated. As regards pharmacokinetics, these compounds have a high bioavailability and penetrate extremely well into tissues and cells. Therapeutic concentrations are obtained in bronchial mucosa and lung tissue. In severe lower respiratory tract infections fluoroquinolones must be given in combination with other antibiotics to prevent the emergence of resistant mutants. The indications of fluoroquinolones in lower respiratory tract infections depend on their antibacterial spectrum. They are particularly useful in the treatment of infections caused by methicillin-sensitive or resistant staphylococci, Pseudomonas spp. (notably in cystic fibrosis) and intracellular organisms. They are not indicated for streptococcal infections, notably those due to Streptococcus pneumoniae, and for anaerobic infections. Fluoroquinolones are currently used mainly in hospital-acquired lower respiratory tract infections, in infected cystic fibrosis and in some acute episodes of chronic bronchitis since they are active against Haemophilus influenzae and Branhamella catarrhalis.