Designing a successful antimicrobial treatment against Devriesea agamarum infections in lizards.

Dermatitis caused by Devriesea agamarum poses a major health problem for the captive maintenance of several desert lizard species. This study was conducted to determine the optimal antimicrobial treatment to eliminate D. agamarum infections from lizards. First, the in vitro susceptibility of 42 D. agamarum isolates was determined for 10 different antimicrobial agents using an agar dilution method. In none of the isolates acquired antimicrobial resistance was demonstrated. Then, two intramuscular treatment protocols using either enrofloxacin or ceftiofur were tested in bearded dragons (Pogona vitticeps) experimentally infected with a D. agamarum strain showing a MIC of 2 microg/ml for enrofloxacin and 0.12 microg/ml for ceftiofur. While D. agamarum could no longer be isolated after 17-18 days of ceftiofur administration, enrofloxacin administration and sham treatment failed in clearing the infection after 27 days of treatment. Based on these results, intramuscular injection of ceftiofur at 5 mg/kg BW q24h was used to treat naturally and clinically infected Uromastyx lizards. This resulted in marked clinical improvement and clearance of infection after 12 days on average. In conclusion, intramuscular administration of ceftiofur at 5 mg/kg BW q24h eliminates D. agamarum in lizards, resulting in clinical cure.