Cerebral cysticercosis by Taenia crassiceps in a domestic cat.

Cerebral cysticercosis by Taenia crassiceps was diagnosed in an adult female domestic shorthair cat. The animal was euthanized 6 weeks after the initial presentation with signs of vomiting, lethargy, and ataxia. The disease took an intermittent relapsing course with the neurological signs progressing eventually to recumbancy and coma. At necropsy, numerous cysticerci were found in the dilated left lateral ventricle and the adjacent brain parenchyma. The cysticerci were identified as metacestodes of T. crassiceps larvae based on size and morphology of the cysts; shape, number, and size of the rostellar hooks; and mode of proliferation, including endogenous and exogenous budding. Cerebral cysticercosis by T. crassiceps is rare in atypical intermediate hosts and has not been described in cats.     

Cerebral coenurosis in a cat

Coenurus serialis, the intermediate stage of Taenia serialis, was the cause of progressive, fatal, intracranial disease in a 5-year-old cat. X-Ray computed tomographic findings were identical to those associated with intracranial parasitic cysts in people, in whom x-ray computed tomographic features are considered pathognomonic and superior to those of other diagnostic methods. The presumed source of the coenurus was the owner's dog.     

Cerebral blastomycosis in a cat

A nine year old domestic shorthair cat was presented to the Small Animal Clinic, Ontario Veterinary College, with anorexia, depression and blindness. The animal died despite treatment. At necropsy, a space occupying mass was located in the left cerebral hemisphere. Histopathologically, the mass consisted of large numbers of fungal yeast-phase cells with an associated pyogranulomatous inflammatory response. The organisms were identified as Blastomyces dermatitidis on the basis of morphology and staining characteristics.

The purpose of this article is to describe the lesions of blastomycosis in the brain of a cat.

     

Cerebral Blastomyces dermatitidis infection in a cat

CASE DESCRIPTION: An 8-year-old domestic shorthair cat was evaluated because of signs of depression, circling, and visual deficits. CLINICAL FINDINGS: The cat had no cutaneous lesions, and results of an ophthalmologic examination and thoracic radiography were within reference limits. Computed tomography of the brain revealed a mass lesion involving the right parietal, temporal, and occipital lobes; the mass was in broad-based contact with the skull and smoothly marginated and had strong homogenous enhancement after contrast agent administration. During craniectomy, samples of the mass were collected for cytologic and histopathologic evaluations and microbial culture. A diagnosis of Blastomyces dermatitidis-associated meningoencephalitis with secondary pyogranulomatous inflammation was made. TREATMENT AND OUTCOME: Amphotericin B (0.25 mg/kg [0.11 mg/lb], IV) was administered on alternate days (cumulative dose, 1.75 mg/kg [0.8 mg/lb]). To minimize the risk of nephrotoxicosis, assessments of serum biochemical variables (urea nitrogen and creatinine concentrations) and urinalyses were performed at intervals. The third dose of amphotericin B was postponed 48 hours because the cat became azotemic. The cat subsequently received fluconazole (10 mg/kg [4.5 mg/lb], PO, q 12 h) for 5.5 months. Six months after discontinuation of that treatment, the cat appeared healthy and had no signs of relapse. CLINICAL RELEVANCE: Brain infection with B dermatitidis is typically associated with widespread disseminated disease. The cat of this report had no evidence of systemic disease. Blastomycosis of the CNS should be considered as a differential diagnosis for brain lesions in cats from areas in which B dermatitidis is endemic.     

Cerebral vascular hamartoma in a geriatric cat

An 11-year-old castrated male domestic medium hair cat was presented with neurological signs consistent with a right thalamocortical lesion. Computed tomography (CT) images revealed a heterogeneously, hyperattenuating, poorly contrast enhancing intra-axial mass within the right lateral ventricle. The histological diagnosis at post-mortem examination was vascular hamartoma with hemorrhage and necrosis. This is the first report of a vascular hamartoma affecting the thalamocortex in a geriatric cat. Also, this is the first time that CT images of a feline cerebral vascular hamartoma have been reported.     

Cerebral high-grade astrocytoma (glioblastoma) in a cat

A cerebral tumour was found in the right frontal lobe of a 7-year-old female mongrel cat. The mass showed infiltrative growth and caused deformation of the corpus callosum. Histopathologically, the tumour cells showed anaplasia, pleomorphism and mitotic figures. Necrosis and vascular proliferation were prominent. The neoplastic cells surrounded areas of necrosis, but as an indistinct pseudopalisade formation. Immunohistochemically, low numbers of tumour cells labelled positively for anti-glial fibrillary acidic protein and anti-S100 protein. Electron microscopically, the majority of tumour cells had no filaments and cytoplasmic processes, but the differentiated cells presented cytoplasmic filaments and glycogen granules. Based on these findings, the tumour was diagnosed as cerebral high-grade astrocytoma, glioblastoma.     

Cerebral cysticercosis in pigs studied by computed tomography and necropsy

An original technique for computed tomography (CT) of the pig's brain is described. Brains of 11 cysticercotic pigs were studied by CT and by macroscopic and microscopic examination after necropsy, in order to compare the tomographic images with the anatomic findings. By CT, cysticerci could be seen in all the brains except one which had only one parasite. Good correlation was found when the CT sections were compared with the anatomic slices, nevertheless not all cysticerci seen during necropsy examination could be identified in the CT images. Only two parasites were found in the ventricles. There were difficulties in differentiating submeningeal and parenchymal localization of the cysticerci. Most cysticerci had similar morphologic appearance; inflammatory reactions of different degrees and characteristics were observed around some of them.     

Megaesophagus in a cat

Megaesophagus in an eight month old Siamese cat is described. Initially, a cause for the vomiting was not discovered and the cat was treated for pyloric spasm. Several months later the same cat, in poor physical condition, was presented with a palpable bulge along its ventral neck. At this time a very dilated and flaccid esophagus was found. An exploratory thoracotomy was done but a cause for the megaesophagus was not discovered.