[Flouroquinolones of the third and fourth generations]

Levofloxacin, levorotatory isomer of ofloxacine, is the only FQ3G on the belgian market since the middle of 2000 and is a little more efficient than the FQ2G against S. pneumoniae. The FQ4G are in vitro active against the common and atypic respiratory pathogenes and significantly more efficient against the Gram positive cocci, principally against S. pneumoniae. Their long duration of action allows one oral administration a day sufficient to obtain bactericidal levels in the serum. Their secondary effects are located principally at the level of digestive tract, neurologic system or cutaneous area. In the U.S.A., several FQ4G (clina-, grepa-, spar-, trova-floxacin) were withdrawn from use after observance of severe toxicity, while there were being administrated on a large scale. Furthermore, two of these "respiratory" FQ4G (gemi- and moxifloxacin) should reinforced our therapeutic armoury, moxifloxacin as of 2002 and gemifloxacin as of 2004. The position of FQ3G and 4G are in discussion. In the case of pneumonia acquired in the community and confirmed by X-Ray, our recommendation is to administer a new FQ at the first choice if the patient is allergic to penicillin, debilitated or if a penicillin resistant S. pneumoniae is suspected (epidemiology, recent antibiotherapy) and at the second choice if it is resistance to penicilline or to macrolide, in case of atypic pneumonia. Today, the majority of the pneumonia acquired outside the hospital is empirically treated with a betalactam (oral or intravenous), with or without macrolide. The new FQ are important drugs. One must avoid overprescription which leads to bacterial resistance (especially S. pneumoniae).