A case of chronic lymphocytic leukemia (CLL) in a Maltese dog

An 11-year-old, 3.3 kg, male Maltese dog was referred to Veterinary Teaching Hospital of Konkuk University because of diarrhea and severe anemia. Abnormal physical examination findings included left submandibular lymph node enlargement, pale mucous membrane, cataract, and bloody diarrhea. Results of hematologic examination revealed a marked lymphocytosis resulting in leukocytosis and the markedly increased numbers of small, well-differentiated lymphocytes in the peripheral blood. Serum biochemical abnormalities consisted of elevated AST and ALP, hyperphosphatemia, hypoglycemia, and hypoalbuminemia. Radiographic examination showed cardiomegaly and hepatosplenomegaly. Results of urinalysis included bilirubinuria and proteinuria. Based on results of examination described above, chronic lymphocytic leukemia was diagnosed. Chemotherapy was initiated with cyclophosphamide ($300mg/m^2$, IV once every 2 weeks), vincristine ($0.75mg/m^2$, IV once every 2 weeks, alternating weeks with the cyclophosphamide), and plus prednisolone ($50mg/m^2$, PO, SID for a week, then $20mg/m^2$, PO every other day). The response to chemotherapy was partially present. This study first demonstrates clinicopathological findings and chemotherapeutic response of chronic lymphocytic leukemia in Korea.