title: Diagnosis and treatment of chronic lymphocytic leukemia in a bat-eared fox (Otocyon megalotis).
abstract: METHODS
  Severe lymphocytosis and leukocytosis were detected during examination of a 10-year-old sexually intact male bat-eared fox (Otocyon megalotis) with regionally extensive alopecia.
  
  
  RESULTS
  A CBC revealed severe leukocytosis (39,100 leukocytes/μL) and marked lymphocytosis (90%). A blood smear consisted predominantly of intermediate-sized lymphocytes and few large lymphocytes, with mild to moderate nuclear atypia. These findings were highly suggestive of chronic lymphocytic leukemia (CLL). Cytologic evaluation of bone marrow aspirates revealed no evidence of overt malignancy, with 10% of all cells identified as small to intermediate-sized mature lymphocytes.
  
  
  RESULTS
  Treatment with chlorambucil and prednisone administered orally over a 1.8-year period decreased the leukocyte and lymphocyte counts to within reference intervals with no adverse effects. Although repeated flow cytometry revealed evidence of residual disease, the fox remained free of clinical disease, and WBC counts were within reference intervals for this species. At 22 months after initial evaluation, the fox was euthanized because of debilitating arthritis. No evidence of CLL was detected grossly or histologically during necropsy.
  
  
  CONCLUSIONS
  To the authors' knowledge, this was the first report of CLL in a bat-eared fox and first successful treatment in a nondomestic carnivore. Treatment in accordance with a chemotherapeutic protocol successfully resolved the leukocytosis and lymphocytosis with no serious adverse effects. Description of this fox and the treatment protocol should provide a valuable reference for future cases in this and other nondomestic canine species.
authors.affiliation: Illinois Zoological and Aquatic Animal Residency Program, College of Veterinary Medicine, University of Illinois, Urbana, IL 61802.
authors.forename: Benjamin N
authors.initials: BN
authors.lastname: Nevitt
authors.forename: Jennifer N
authors.initials: JN
authors.lastname: Langan
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Adkesson
authors.forename: Jennifer A
authors.initials: JA
authors.lastname: Landolfi
authors.forename: Rand
authors.initials: R
authors.lastname: Wilson
mesh_terms: D000818:Animals; D000836:Animals, Zoo; D018906:Antineoplastic Agents, Alkylating / Q000008:administration & dosage / Q000627:therapeutic use; D018931:Antineoplastic Agents, Hormonal / Q000008:administration & dosage / Q000627:therapeutic use; D002699:Chlorambucil / Q000008:administration & dosage / Q000627:therapeutic use*; D005589:Foxes; D007945:Leukemia, Lymphoid / Q000175:diagnosis / Q000188:drug therapy / Q000662:veterinary*; D008297:Male; D011241:Prednisone / Q000008:administration & dosage / Q000627:therapeutic use*
chemical_list: D018906:Antineoplastic Agents, Alkylating; D018931:Antineoplastic Agents, Hormonal; D002699:Chlorambucil; D011241:Prednisone