title: Multiple myeloma in a dog with multiple concurrent infectious diseases and persistent polyclonal gammopathy.
abstract: A 12-year-old, spayed female, mixed-breed dog was presented for acute hematuria, stranguria, polyuria, and polydipsia, as well as lameness for 8 days. Previous medical history included treatment for infection with Ehrlichia canis, Anaplasma phagocytophilum, Leishmania infantum, and Dirofilaria immitis 6.5 years prior to presentation. Besides persistently increased antibody titers to E canis and A phagocytophilum, polyclonal gammopathy with a monoclonal spike and moderate hypercalcemia were observed. There was marked hematuria, and Staphylococcus aureus was cultured from urine. Two weeks after successful treatment of the urinary tract infection, radiographs showed an extensive destructive monostotic lesion of the right humerus. Cytologic examination of fine-needle aspirates of this lesion revealed a neoplastic round cell population suggestive of multiple myeloma. The dog was treated with melphalan and prednisolone for suspected multiple myeloma and doxycycline for suspected ehrlichiosis and anaplasmosis. Treatments lead to resolution of the clinical signs, hypercalcemia, and monoclonal gammopathy, and there was radiographic improvement of bone lesions; polyclonal gammopathy persisted. About one year after presentation the dog was still in clinical remission. This is a rare report of a dog with suspected multiple myeloma and a history of multiple chronic infectious diseases, suggesting that chronic infection and uncontrolled long-term stimulation of the immune system could contribute to the pathogenesis of multiple myeloma.
authors.affiliation: Division of Radiation Oncology, University of Zurich, Zurich, Switzerland. cgeigy@vetclinics.uzh.ch
authors.forename: Caroline
authors.initials: C
authors.lastname: Geigy
authors.forename: Barbara
authors.initials: B
authors.lastname: Riond
authors.forename: Carla Rohrer
authors.initials: CR
authors.lastname: Bley
authors.forename: Paula
authors.initials: P
authors.lastname: Grest
authors.forename: Patrick
authors.initials: P
authors.lastname: Kircher
authors.forename: Hans
authors.initials: H
authors.lastname: Lutz
mesh_terms: D041081:Anaplasma phagocytophilum; D000818:Animals; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D000970:Antineoplastic Agents / Q000627:therapeutic use; D003937:Diagnosis, Differential; D004283:Dog Diseases / Q000175:diagnosis / Q000188:drug therapy / Q000473:pathology*; D004285:Dogs; D041061:Ehrlichia canis; D016873:Ehrlichiosis / Q000150:complications / Q000188:drug therapy / Q000662:veterinary; D005260:Female; D018314:Leishmania infantum; D007898:Leishmaniasis, Visceral / Q000150:complications / Q000662:veterinary; D009101:Multiple Myeloma / Q000150:complications / Q000188:drug therapy / Q000473:pathology / Q000662:veterinary*; D013203:Staphylococcal Infections / Q000150:complications / Q000382:microbiology / Q000662:veterinary; D014552:Urinary Tract Infections / Q000150:complications / Q000382:microbiology / Q000662:veterinary
chemical_list: D000900:Anti-Bacterial Agents; D000970:Antineoplastic Agents