RESUMO
CASE DESCRIPTION: A 5.5-year-old neutered male mixed-breed dog was presented for evaluation of a 5-month history of deviation of the right globe upon opening the mouth and a 1-month history of conjunctivitis in the same eye. Clinical findings, diagnostic imaging results, treatment and follow-up are described. CLINICAL FINDINGS: When the mouth was opened, the right globe deviated rostrally and laterally. There was no pain or resistance to opening the mouth, or resistance to retropulsion of the globe. No other abnormalities were observed. Computed tomography was performed, revealing a contrast-enhancing region associated with the right masseter muscle impinging into the right orbit; this was more pronounced with the mouth open. Cytology revealed a small number of mildly to moderately atypical mesenchymal cells. Histopathology was consistent with polyphasic myositis, with a predominance of lymphocytes and plasma cells. No infectious agents were identified. Serum antibody titers for Toxoplasma gondii and Neospora caninum were negative. Serum titers for 2 M antibody were positive at 1:500, consistent with a diagnosis of masticatory muscle myositis. TREATMENT AND OUTCOME: Therapy with prednisone was initiated. During a follow-up period of 5 months, there was no recurrence of clinical signs, and the dose of prednisone was reduced by 25%. CLINICAL SIGNIFICANCE: To the authors' knowledge, this is the first reported case of masticatory muscle myositis causing dynamic exophthalmos and strabismus in a dog.
Assuntos
Doenças do Cão/diagnóstico , Exoftalmia/veterinária , Músculos da Mastigação , Miosite/veterinária , Estrabismo/veterinária , Animais , Anti-Inflamatórios/uso terapêutico , Doenças do Cão/etiologia , Doenças do Cão/patologia , Cães , Exoftalmia/diagnóstico , Exoftalmia/etiologia , Exoftalmia/patologia , Masculino , Miosite/complicações , Miosite/diagnóstico , Miosite/tratamento farmacológico , Prednisona/uso terapêutico , Estrabismo/diagnóstico , Estrabismo/etiologia , Estrabismo/patologiaRESUMO
Treatment of chronic monocytic leukemia (CMoL) in dogs has traditionally consisted of hydroxyurea. The use of tyrosine kinase inhibitors has been proposed as a treatment option for dogs with CMoL but has never been reported. We report a case of CMoL in a young dog that achieved clinical remission with treatment with the tyrosine kinase inhibitor toceranib and prednisone.