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 PCR 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.

Use of enrofloxacin for treatment of large-form Haemobartonella felis in experimentally infected cats.

OBJECTIVE: To compare treatment with enrofloxacin and doxycycline with no treatment in cats experimentally infected with Haemobartonella felis. DESIGN: Prospective case-control study. ANIMALS: 16 cats. PROCEDURE: Cats were inoculated with large-form H. felis from a chronically infected donor. Cats were assigned to 1 of 4 treatment groups: doxycycline (5 mg/kg [2.3 mg/lb], p.o., q 12 h), low-dose enrofloxacin (5 mg/kg, p.o., q 24 h), high-dose enrofloxacin (10 mg/kg [4.5 mg/lb], p.o., q 24 h), and an untreated control group. Clinical signs, Hct, blood smears, and a polymerase chain reaction (PCR) assay were used to monitor progression of the infection. RESULTS: All cats were confirmed to be infected with H. felis via blood smear evaluations and PCR assay results. Treatment had no effect on Hct during the intratreatment period, but Hct values were significantly greater in the low-dose enrofloxacin group, compared with the control group, during the posttreatment period. During the intratreatment period, H. felis organism counts per 1,000 RBC in the doxycycline treatment and the high-dose enrofloxacin treatment groups decreased at a significantly faster rate than those in the control group. In the posttreatment period, organism counts in the doxycycline treatment group and the low- and high-dose enrofloxacin groups decreased at significantly faster rates than counts in the control group. There was no significant effect of treatment on the number of positive PCR assay results. Two cats treated with enrofloxacin and 1 cat treated with doxycycline completely cleared the H. fe is organism despite presumed immunosuppression caused by glucocorticoids. CONCLUSIONS AND CLINICAL RELEVANCE: Results support the hypothesis that enrofloxacin has anti-H. felis effects.