Janet C. Martin1, DVM; Antony S. Moore2, MVSc, DACVJM; Dave Ruslander3, DVM, DACVR; Jorg Mayer1, Dr med vet, MSc; James Raymond4, DVM, DACVP; Michael Garner4, DVM, DACVP; Joyce Knoll1, VMD, PhD, DACVP; Stephanie James5, DVM; Amy Bengtson1, BS, AHT
1Roger Williams Park Zoo, Providence, RI, USA; 2School of Veterinary Medicine, Tufts University, North Grafton, MA, USA; 3North Carolina State College of Veterinary Medicine, Raleigh, NC, USA; 4Northwest ZooPath, Snohomish, WA, USA; 5Wildlife Conservation Society, Bronx, NY, USA
An adult female sungazer lizard (Cordylus giganteus) was presented for routine postshipment quarantine. On physical examination, it appeared in good body condition except for unusually pale mucus membranes and evidence of a previous femoral pore abscess on the left hind leg. A CBC revealed anemia with a hematocrit of 7%, and a WBC of 3.1x103/µl with a differential of 73% heterophils, 20% lymphocytes, 3% monocytes, and 4% basophils. A few reactive lymphocytes were noted. Strongyle ova were identified on fecal parasitology examination. A deworming treatment was initiated with ivermectin. A subsequent CBC at 3 wk revealed a continued anemia, and large, immature lymphocytes comprising 75% of the leukocytes. This was followed the next week by an increase in the total WBC to 80.1x103/µl, with 87% lymphoblasts. This was considered to be consistent with a diagnosis of acute lymphoblastic leukemia. Treatment with prednisone was initiated at 0.2 mg every 72 hr p.o. scaled from the canine dose of 2 mg/kg every 24 hr. During the following 3 mo of treatment, the WBC remained elevated, ranging between 49–138x103/µl with lymphocytes and lymphoblasts comprising over 90% of the total leukocytes. The hematocrit remained between 10–15%. Approximately 6 mo after the initial presentation, the prednisolone treatment was discontinued and a single, low dose, whole body radiation treatment of 1 Gray was administered. One-month postradiation, the WBC remained elevated at 34.3x103/µl with a predominance of lymphoblasts. At 2 mo postradiation, the WBC had decreased to 9.1x103/µl. At 3 mo the WBC was further decreased to 2.9x103/µl with a normal differential, and the hematocrit was 22%. At 6, 8, and 11 mo post-treatment, the WBC, differential, and hematocrit all remained within normal limits. Approximately 11 mo after radiation treatment, the lizard died of complications arising from reabscessation at the site of the previous femoral pore abscess. The CBC at this time, and subsequent histopathology revealed no evidence of leukemia. There were some areas of squamous metaplasia in the pulmonary parenchyma and the mucosal lining of other organs, as well as some intestinal fibrosis, which were suggestive of postradiation changes in these organs. It is unknown if this animal would have been reproductively viable postradiation, however the treatment maintained her value to the collection as an exhibit animal.