Conclusions

Abstract

The microbiology group concluded that Streptococcus pneumoniae and Haemophilus influenzae are the most important pathogens which have to be eradicated in respiratory tract infections. There are quite large differences in activity between the current antimicrobial agents used for treatment and they showed that the new fluoroquinolones have good activity against respiratory tract pathogens, including intracellular pathogens, and S. pneumoniae. Thus, the spectrum of activity of the new fluoroquinolones is adapted to respiratory infections. The resistance group showed that trends in increasing resistance among respiratory pathogens are opening the way for a broader use of fluoroquinolones. For example, a Haemophilus strain which does not respond to macrolides, or β-lactams, will need a fluoroquinnolone. Primary mutants are the key issue for the development of resistance to fluoroquinolones, because the detection of the such mutants and the proper use of fluoroquinolones able to eliminate early resistant variants may reduce the development of resistance in the future. At present, despite the use of ofloxacin and ciprofloxacin, there is little resistance to the fluoroquinolones in respiratory pathogens, indicating that the selection pressure has not been strong enough. The pharmacokinetics and pharmacodynamics group showed how the differences in pharmacokinetics and pharmacodynamics between the various fluoroquinolones, such as metabolism and elimination by the kidney or by the liver, should be used as a tool to understand variations in clinical results with different fluoroquinolones. An important aspect is the dose schedule in order to prevent the selection of resistant strains. In clinical studies, dosing and particularly the MIC should be taken into account. The lower respiratory tract infection group reached a consensus that the new fluoroquinolones are more active against S. pneumoniae and can be considered as a suitable treatment for lower respiratory tract infections, including possible first-line treatment. The importance of the step-down therapy from intravenous to oral was emphasized, along with the need for future clinical studies to be performed to optimize the duration of treatment in lower respiratory tract infections. The upper respiratory tract infection group concluded that there is no role for fluoroquinolones in pharyngitis. In addition, as they are not currently licensed for pediatrics, their use in acute otitis media is limited. However, in the future, they may be useful in this indication because of the high numbers of strains resistant to currently used antibiotics. Fluoroquinolones can be used in acute sinusitis in adults but more studies are needed. To summarize, the meeting has contributed to our knowledge and understanding of the new fluoroquinolones and their clinical indications in the treatment of respiratory tract infections. It is clear that these agents do form a new class of ‘respiratory fluoroquinolones’ with their improved activity against the major respiratory pathogens. Further clinical studies are required to clarify issues such as dosing and duration of treatment and to confirm their indications in lower and upper respiratory tract infections and their possible future use in children.