Fluoroquinolones (ciprofloxacin, moxifloxacin and norfloxacin) (FQ) are essential agents for directed treatment of certain types of resistant aerobic Gram negative bacterial species where FQ susceptibility  has been proven.  They are best avoided as empirical  therapy or where there is an alternative due to these potential serious side effects:

1. Bacterial resistance ecology and C. difficile infections :  FQ overuse in community and hospital settings has lead to widespread resistance in Gram negatives and Gram positive bacteria such as Streptococcus pneumoniae with evidence of increased transmission and morbidity from MRSA, multi-resistant Gram negatives and C. difficile.  
2. Side effects involving tendons, muscles, joints, nerves, and central nervous system. In May 2016, the U.S. F.D.A. advised that these FQ side effects generally outweigh the benefits for patients with acute sinusitis, acute bronchitis, and uncomplicated urinary tract infections who have other treatment options.
3.  Sudden death due to prolonged QT syndrome/torsades:   significant incidence with some FQ and macrolide antibiotics.

Reductions in usage in hospital and community settings have been associated with subsequent increased FQ susceptibility in E. coli as shown from an excellent recent study discussed previously. That study indicated a threshold effect – quinolone resistance fell significantly only after use reduced below 20 defined daily doses per 1000 patient-days.

HNE LHD monitors hospital usage of FQ and third generation cephalosporins across all facilities.  The current target for FQ is to maintain usage below 30 DDD/1000 patient-days, though this target will probably be reconsidered.  For recent data on local rates of FQ resistance, see HNELHD antibiogram reports for 2015.

Stay tuned for several future postings about when and when not to turn to FQ and a look at our local recent quinolone usage figures.