title: Tick-Borne Relapsing Fever in Dogs.
abstract: BACKGROUND
  In the United States, Tick-Borne Relapsing Fever (TBRF) in dogs is caused by the spirochete bacteria Borrelia turicatae and Borrelia hermsii, transmitted by Ornithodoros spp. ticks. The hallmark diagnostic feature of this infection is the visualization of numerous spirochetes during standard blood smear examination. Although the course of spirochetemia has not been fully characterized in dogs, in humans infected with TBRF the episodes of spirochetemia and fever are intermittent.
  
  
  OBJECTIVE
  To describe TBRF in dogs by providing additional case reports and reviewing the disease in veterinary and human medicine.
  
  
  METHODS
  Five cases of privately-owned dogs naturally infected with TBRF in Texas are reviewed.
  
  
  METHODS
  Case series and literature review.
  
  
  RESULTS
  All dogs were examined because of lethargy, inappetence, and pyrexia. Two dogs also had signs of neurologic disease. All dogs had thrombocytopenia and spirochetemia. All cases were administered tetracyclines orally. Platelet numbers improved and spirochetemia and pyrexia resolved in 4 out of 5 dogs, where follow-up information was available.
  
  
  CONCLUSIONS
  TBRF is likely underdiagnosed in veterinary medicine. In areas endemic to Ornithodoros spp. ticks, TBRF should be considered in dogs with thrombocytopenia. Examination of standard blood smears can provide a rapid and specific diagnosis of TBRF when spirochetes are observed.
authors.affiliation: Texas A&M Veterinary Medical Diagnostic Laboratory, Texas A&M University, College Station, TX.
authors.forename: J
authors.initials: J
authors.lastname: Piccione
authors.affiliation: Department of Veterinary Pathobiology, College of Veterinary Medicine & Biomedical Sciences, Texas A&M University, College Station, TX.
authors.forename: G J
authors.initials: GJ
authors.lastname: Levine
authors.affiliation: Department of Small Animal Clinical Sciences , College of Veterinary Medicine & Biomedical Sciences, Texas A&M University, College Station, TX.
authors.forename: C A
authors.initials: CA
authors.lastname: Duff
authors.affiliation: Department of Small Animal Clinical Sciences , College of Veterinary Medicine & Biomedical Sciences, Texas A&M University, College Station, TX.
authors.forename: G M
authors.initials: GM
authors.lastname: Kuhlman
authors.affiliation: Department of Small Animal Clinical Sciences , College of Veterinary Medicine & Biomedical Sciences, Texas A&M University, College Station, TX.
authors.forename: K D
authors.initials: KD
authors.lastname: Scott
authors.affiliation: Department of Veterinary Pathobiology, College of Veterinary Medicine & Biomedical Sciences, Texas A&M University, College Station, TX.
authors.forename: M D
authors.initials: MD
authors.lastname: Esteve-Gassent
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D001899:Borrelia Infections / Q000175:diagnosis / Q000188:drug therapy / Q000662:veterinary*; D003937:Diagnosis, Differential; D004283:Dog Diseases / Q000175:diagnosis* / Q000188:drug therapy; D004285:Dogs; D005260:Female; D008297:Male; D012061:Relapsing Fever / Q000175:diagnosis / Q000188:drug therapy / Q000662:veterinary*; D013987:Ticks / Q000382:microbiology
chemical_list: D000900:Anti-Bacterial Agents
keywords: Bacteremia; Borrelia; Spirochete; Spirochetemia; Thrombocytopenia