Résistance aux fluoroquinolones en 2010 : quel impact pour la prescription en réanimation ?

Resistance to fluoroquinolones (FQ) is the direct consequence of the rise in FQ consumption worldwide. Resistance rates have reached high numbers in hospital-settings for Gram positive and Gram negative organisms, forbidding the empirical use of FQ in the context of severely-ill patients. Rates of resistance remain low for Streptococcus pneumoniae in France; nevertheless, strains carrying first-level resistance to FQ are emerging. For severely-ill patients, pharmacokinetic and pharmacodynamic (PK/PD) parameters must be taken into account when prescribing a FQ. Indeed, for strains having acquired first-levels of resistance but which remain susceptible according to the official criteria, it may be impossible to reach the necessary doses to be clinically efficient without being toxic. An association or the switch to another class of antibiotics may therefore be necessary. Another problem is that any treatment by a FQ has an ecological impact in particular through the selection of resistance strains in the commensal flora, which is impossible to avoid. Optimisation of PK/PD parameters and combinations with other classes of antibiotics may limit at least the emergence of resistant strains in the infectious focus.