Use of pradofloxacin to treat experimentally induced Mycoplasma hemofelis infection in cats

Objective-To evaluate the efficacy of the fluoroquinolone pradofloxacin in the treatment of cats experimentally infected with Mycoplasma hemofelis. Animals-23 young adult specific-pathogen-free cats. Procedures-Cats were inoculated with M hemofelis from a chronically infected donor and assigned to 1 of 4 treatment groups: a doxycycline group, a low-dose-pradofloxacin group, a high-dose-pradofloxacin group, and an untreated control group. Treatment was initiated for 14 days when M hemofelis infection was detected via PCR assay and clinical signs of hemoplasmosis were present. Cats that had negative PCR assay results after treatment were administered a glucocorticoid and monitored via PCR assay for an additional 4 weeks. Results-All cats yielded positive results for M hemofelis via conventional PCR and quantitative PCR assays and developed anemia. The low-dose-pradofloxacin group had significantly lower M hemofelis copy numbers than the doxycycline group. Six cats treated with pradofloxacin yielded negative results during treatment. Of those cats, 4 yielded negative conventional PCB assay results and all yielded negative quantitative PCR assay results for M hemofelis 1 month after administration of high-dose glucocorticoids. Conclusions and Clinical Relevance-Pradofloxacin had anti-M hemofelis effects similar to those of doxycycline. In addition, pradofloxacin may be more effective at long-term M hemofelis organism clearance than doxycycline. (Am J Vet Res 2009;70:105-111)