title: Disseminated protothecosis diagnosed by evaluation of CSF in a dog.
abstract: A 5-year-old female spayed Shetland Sheepdog Mix dog was evaluated for a history of recent seizure activity, progressive hind limb ataxia, polyuria, and polydipsia and no history of gastrointestinal signs. Physical examination findings included conscious proprioceptive deficits, ataxia, and anterior uveitis along with a hypermature cataract in the right eye. Results of a CBC, serum biochemical profile, urinalysis, and computed tomography scan of the brain were unremarkable. Cerebrospinal fluid (CSF) analysis revealed marked eosinophilic pleocytosis and rare organisms consistent with Prototheca spp within neutrophils and macrophages. On postmortem histologic examination, mononuclear inflammation and numerous intralesional algal organisms, similar to those seen on the cytologic preparation of CSF, were found in the brain, eyes, kidneys, and heart. Abnormalities were not detected on gross and histologic examination of the gastrointestinal tract. Cultures of CSF and subdural/olfactory bulb, but not intestinal tract, yielded growth of Prototheca spp, and PCR analysis and DNA sequencing confirmed the organism as Prototheca zopfii genotype 2. We have reported a rare case of disseminated protothecosis that was diagnosed by evaluation of CSF in a dog presented with neurologic signs and no overt enteric disease. Protothecosis should be considered as a rare cause of seizures, even in the absence of obvious enteric signs, and should be included in the differential diagnosis of eosinophilic pleocytosis.
authors.affiliation: Department of Veterinary Pathobiology, Center for Veterinary Health Sciences, Oklahoma State University, 250 McElroy Hall, Stillwater, OK 74078, USA. devai@okstate.edu
authors.forename: Laura V
authors.initials: LV
authors.lastname: Lane
authors.forename: James H
authors.initials: JH
authors.lastname: Meinkoth
authors.forename: Jill
authors.initials: J
authors.lastname: Brunker
authors.forename: Stephen K
authors.initials: SK
authors.lastname: Smith
authors.forename: Timothy A
authors.initials: TA
authors.lastname: Snider
authors.forename: John
authors.initials: J
authors.lastname: Thomas
authors.forename: Dan
authors.initials: D
authors.lastname: Bradway
authors.forename: Brenda C
authors.initials: BC
authors.lastname: Love
mesh_terms: D000818:Animals; D001483:Base Sequence; D001921:Brain / Q000473:pathology; D002494:Central Nervous System Infections / Q000134:cerebrospinal fluid / Q000175:diagnosis / Q000662:veterinary*; D018744:DNA, Plant / Q000134:cerebrospinal fluid / Q000737:chemistry / Q000302:isolation & purification; D003937:Diagnosis, Differential; D004283:Dog Diseases / Q000134:cerebrospinal fluid* / Q000175:diagnosis; D004285:Dogs; D005260:Female; D005838:Genotype; D011525:Prototheca / Q000235:genetics / Q000302:isolation & purification*
chemical_list: D018744:DNA, Plant