Clinical Segmental Myelitis Associated with an Unidentified Toxoplasma-Like Parasite in a Cat

Abstract

A single species of the protozoan parasite Toxoplasma changes were felt to be diagnostic. Cerebrospinal fluid colgondii is known to parasitize virtually all warm-blooded anlected at the time of myelogram contained 117 WBC/μl, 4210 imals, including humans. 3 Recently, another unidentified red blood cells/μl, and 186 mg/dl of protein. The WBC were parasite, antigenically similar to Toxbplasma but slightly difmostly small lymphocytes. Based on the elevated protein and ferent structurally was found in a cat with a myeloproliferthe cytologic changes, a diagnosis of nonsuppurative meninative disease. Primary disease in a cat associated with this gomyelitis was made. unidentified parasite is reported here. A 3-year-old intact female domestic long haired cat was Based on the evidence of inflammatory disease, a feline leukemia virus test was performed, which was negative. Sepresented to The Veterinary Teaching Hospital, The Ohio State University-Columbus, for evaluation of a left thoracic rum electrophoresis was performed, looking for a based gammopathy, such as seen with feline infectious broadperitolimb gai prior to t disturbance. presentation The and abnormal described gait was noticed 3 weeks as a “lameness.” Over nitis. The electrophoresis results were normal. Antibodies to T. gondii were found in 1:4,096 dilution of the serum tested the course of 3 weeks, the cat aspect of the carpus. At times, began the leg to walk on the dorsal would be carried. The owner brought the cat for cortisone by the referring evaluation because treatment with veterinarian had not alleviated the clinical signs. Additionally, the left pelvic limb was now abnormal. Neurologic and ophthalmologic abnormalities were found on physical examination. The cat had anisocoria, with the left pupil smaller than the right. The pupillary light reflexes were preserved. There was slight protrusion of the nictitans on the left and ptosis of the left palpebrum. The triceps and biceps muscles in the left thoracic limb were atrophied. The left pelvic limb was weak and had deficits in the postural reactions. The apparent lower motor neuron weakness of the left thoracic limb, the Homer’s syndrome, and the weakness of the left pelvic limb indicated a lesion in the spinal cord at the level of the cervical intumescence (C6-T2). The ophthalmologic examination revealed a focal area of hyperreflectivity surrounded by edema in the right eye. These changes in eu the indirect hemagglutination test. thanasia rather than treat the cat. The The owner elected cat was euthanized with an overdose was performed. of barbiturate anesthesia, and a necropsy